42 results on '"Wojtkiewicz G"'
Search Results
2. RNAi targeting multiple cell adhesion molecules reduces immune cell recruitment and vascular inflammation after myocardial infarction
- Author
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Massachusetts Institute of Technology. Institute for Medical Engineering & Science, Harvard University--MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology. Department of Chemical Engineering, Koch Institute for Integrative Cancer Research at MIT, Dahlman, James, Xing, Yiping, Shaw, Taylor E., Langer, Robert S, Anderson, Daniel Griffith, Khan, Omar Fizal, Kauffman, Kevin John, Sager, H. B., Dutta, P., Hulsmans, M., Courties, G., Sun, Y., Heidt, T., Vinegoni, C., Borodovsky, A., Fitzgerald, K., Wojtkiewicz, G. R., Iwamoto, Y., Tricot, B., Libby, P., Weissleder, R., Swirski, F. K., Nahrendorf, M., Dahlman, James E., Massachusetts Institute of Technology. Institute for Medical Engineering & Science, Harvard University--MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology. Department of Chemical Engineering, Koch Institute for Integrative Cancer Research at MIT, Dahlman, James, Xing, Yiping, Shaw, Taylor E., Langer, Robert S, Anderson, Daniel Griffith, Khan, Omar Fizal, Kauffman, Kevin John, Sager, H. B., Dutta, P., Hulsmans, M., Courties, G., Sun, Y., Heidt, T., Vinegoni, C., Borodovsky, A., Fitzgerald, K., Wojtkiewicz, G. R., Iwamoto, Y., Tricot, B., Libby, P., Weissleder, R., Swirski, F. K., Nahrendorf, M., and Dahlman, James E.
- Abstract
Myocardial infarction (MI) leads to a systemic surge of vascular inflammation in mice and humans, resulting in secondary ischemic complications and high mortality. We show that, in ApoE−/− mice with coronary ligation, increased sympathetic tone up-regulates not only hematopoietic leukocyte production but also plaque endothelial expression of adhesion molecules. To counteract the resulting arterial leukocyte recruitment, we developed nanoparticle-based RNA interference (RNAi) that effectively silences five key adhesion molecules. Simultaneously encapsulating small interfering RNA (siRNA)–targeting intercellular cell adhesion molecules 1 and 2 (Icam1 and Icam2), vascular cell adhesion molecule 1 (Vcam1), and E- and P-selectins (Sele and Selp) into polymeric endothelial-avid nanoparticles reduced post-MI neutrophil and monocyte recruitment into atherosclerotic lesions and decreased matrix-degrading plaque protease activity. Five-gene combination RNAi also curtailed leukocyte recruitment to ischemic myocardium. Therefore, targeted multigene silencing may prevent complications after acute MI., National Institutes of Health (U.S.) (Grants HL114477, HL117829, HL096576, and K99- HL121076), Massachusetts General Hospital (Research Scholar Award), Harvard Catalyst, Harvard Clinical and Translational Science Center
- Published
- 2017
3. Endotracheal tubes cleaned with a novel mechanism for secretion removal: A randomized controlled clinical study
- Author
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Pinciroli, R, Mietto, C, Piriyapatsom, A, Chenelle, C, Thomas, J, Pirrone, M, Bry, L, Wojtkiewicz, G, Nahrendorf, M, Kacmarek, R, Berra, L, PINCIROLI, RICCARDO, BERRA, LORENZO, Pinciroli, R, Mietto, C, Piriyapatsom, A, Chenelle, C, Thomas, J, Pirrone, M, Bry, L, Wojtkiewicz, G, Nahrendorf, M, Kacmarek, R, Berra, L, PINCIROLI, RICCARDO, and BERRA, LORENZO
- Abstract
INTRODUCTION: Intubation compromises mucus clearance, allowing secretions to accumulate inside the endotracheal tube (ETT). The purpose of this trial was to evaluate a novel device for ETT cleaning. We hypothesized that its routine use would reduce tube occlusion due to mucus accumulation, while decreasing airway bacterial colonization. METHODS: Subjects were randomized to either the use of the device every 8 h, or the institutional standard of care (blind tracheal suction) only. ETTs were collected at extubation and analyzed with high-resolution computed tomography (HRCT) for quantification of mucus volume. Microbiological testing was performed on biofilm samples. Vital signs and ventilatory settings were collected at the bedside. In-hospital follow-up was conducted, and a final evaluation survey was completed by respiratory therapists. RESULTS: Seventy-four subjects expected to remain intubated for longer than 48 h were enrolled (77 ETTs, 37 treatment vs 40 controls). Treated tubes showed reduced mucus accumulation (0.56 ± 0.12 vs 0.71 ± 0.28 mL; P = .004) and reduced occlusion (6.3 ± 1.7 vs 8.9 ± 7.6%; P = .039). The HRCT slice showing the narrowest lumen within each ETT exhibited less occlusion in cleaned tubes (10.6 ± 8.0 vs 17.7 ± 13.4%, 95% CI: 2–12.1; P = .007). Data on microbial colonization showed a trend in the treatment group toward a reduced ETT-based biomass of bacteria known to cause ventilator-associated pneumonia. No adverse events were reported. The staff was satisfied by the overall safety and feasibility of the device. CONCLUSION: The endOclear is a safe and effective device. It prevents luminal occlusion, thereby better preserving ETT nominal function.
- Published
- 2016
4. Endotracheal Tubes Cleaned With a Novel Mechanism for Secretion Removal: A Randomized Controlled Clinical Study
- Author
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Pinciroli, R., primary, Mietto, C., additional, Piriyapatsom, A., additional, Chenelle, C. T., additional, Thomas, J. G., additional, Pirrone, M., additional, Bry, L., additional, Wojtkiewicz, G. R., additional, Nahrendorf, M. P., additional, Kacmarek, R. M., additional, and Berra, L., additional
- Published
- 2016
- Full Text
- View/download PDF
5. Multimodal targeted high relaxivity thermosensitive liposome for in vivo imaging
- Author
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Kuijten, M.M.P., Hannah Degeling, M., Chen, J.W., Wojtkiewicz, G., Waterman, P., Weissleder, R., Azzi, J., Nicolay, K., Tannous, B.A., Kuijten, M.M.P., Hannah Degeling, M., Chen, J.W., Wojtkiewicz, G., Waterman, P., Weissleder, R., Azzi, J., Nicolay, K., and Tannous, B.A.
- Abstract
Liposomes are spherical, self-closed structures formed by lipid bilayers that can encapsulate drugs and/or imaging agents in their hydrophilic core or within their membrane moiety, making them suitable delivery vehicles. We have synthesized a new liposome containing gadolinium-DOTA lipid bilayer, as a targeting multimodal molecular imaging agent for magnetic resonance and optical imaging. We showed that this liposome has a much higher molar relaxivities r1 and r2 compared to a more conventional liposome containing gadolinium-DTPA-BSA lipid. By incorporating both gadolinium and rhodamine in the lipid bilayer as well as biotin on its surface, we used this agent for multimodal imaging and targeting of tumors through the strong biotin-streptavidin interaction. Since this new liposome is thermosensitive, it can be used for ultrasound-mediated drug delivery at specific sites, such as tumors, and can be guided by magnetic resonance imaging.
- Published
- 2015
6. Tracheal tube obstruction in mechanically ventilated patients assessed by high-resolution computed tomography
- Author
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Mietto, C, Pinciroli, R, Piriyapatsom, A, Thomas, J, Bry, L, Delaney, M, Du Bois, A, Truelove, J, Ackman, J, Wojtkiewicz, G, Nahrendorf, M, Kacmarek, R, Berra, L, Thomas, JG, Delaney, ML, Ackman, JB, Wojtkiewicz, GR, Nahrendorf M, Kacmarek, RM, PINCIROLI, RICCARDO, BERRA, LORENZO, Mietto, C, Pinciroli, R, Piriyapatsom, A, Thomas, J, Bry, L, Delaney, M, Du Bois, A, Truelove, J, Ackman, J, Wojtkiewicz, G, Nahrendorf, M, Kacmarek, R, Berra, L, Thomas, JG, Delaney, ML, Ackman, JB, Wojtkiewicz, GR, Nahrendorf M, Kacmarek, RM, PINCIROLI, RICCARDO, and BERRA, LORENZO
- Abstract
Background:: Tracheal intubation compromises mucus clearance and secretions accumulate inside the tracheal tube (TT). The aim of this study was to evaluate with a novel methodology TT luminal obstruction in critically ill patients. Methods:: This was a three-phase study: (1) the authors collected 20 TTs at extubation. High-resolution computed tomography (CT) was performed to determine cross-sectional area (CSA) and mucus distribution within the TT; (2) five TTs partially filled with silicone were used to correlate high-resolution CT results and increased airflow resistance; and (3) 20 chest CT scans of intubated patients were reviewed for detection of secretions in ventilated patients’ TT. Results:: Postextubation TTs showed a maximum CSA reduction of (mean ± SD) 24.9 ± 3.9% (range 3.3 to 71.2%) after a median intubation of 4.5 (interquartile range 2.5 to 6.5) days. CSA progressively decreased from oral to lung end of used TTs. The luminal volume of air was different between used and new TTs for all internal diameters (P < 0.01 for new vs. used TTs for all studied internal diameters). The relationship between pressure drop and increasing airflow rates was nonlinear and depended on minimum CSA available to ventilation. Weak correlation was found between TT occlusion and days of intubation (R2 = 0.352, P = 0.006). With standard clinical chest CT scans, 6 of 20 TTs showed measurable secretions with a CSA reduction of 24.0 ± 3.9%. Conclusions:: TT luminal narrowing is a common finding and correlates with increased airflow resistance. The authors propose high-resolution CT as a novel technique to visualize and quantify secretions collected within the TT lumen.
- Published
- 2014
7. Ligation of the jugular veins does not result in neural inflammation, demyelination, or neurological deficits in mice
- Author
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Oklu, R., primary, Forghani, R., additional, Atkinson, W., additional, Wojtkiewicz, G., additional, Pulli, B., additional, Iwamoto, Y., additional, Ueno, T., additional, Waterman, P., additional, Truelove, J., additional, and Chen, J.W., additional
- Published
- 2012
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- View/download PDF
8. Abstract No. 449: Ligation of the jugular veins does not result in neural inflammation, demyelination or neurological deficits in mice
- Author
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Oklu, R., primary, Forghani, R., additional, Atkinson, W., additional, Wojtkiewicz, G., additional, Pulli, B., additional, Iwamoto, Y., additional, Ueno, T., additional, Waterman, P., additional, Truelove, J., additional, and Chen, J.W., additional
- Published
- 2012
- Full Text
- View/download PDF
9. Evaluation of renal quantitative T2* changes on MRI following administration of ferumoxytol as a T2* contrast agent
- Author
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Hedgire SS, McDermott S, Wojtkiewicz GR, Abtahi SM, Harisinghani M, and Gaglia JL
- Subjects
Medicine (General) ,R5-920 - Abstract
Sandeep S Hedgire,1 Shaunagh McDermott,1 Gregory R Wojtkiewicz,1 Seyed Mahdi Abtahi,1 Mukesh Harisinghani,1 Jason L Gaglia21Center for Systems Biology, Massachusetts General Hospital, Richard B Simches Research Center, 2Joslin Diabetes Center, Boston, MA, USAPurpose: To evaluate the time-dependent changes in regional quantitative T2* maps of the kidney following intravenous administration of ferumoxytol.Materials and methods: Twenty-four individuals with normal kidney function underwent T2*-weighted MRI of the kidney before, immediately after, and 48 hours after intravenous administration of ferumoxytol at a dose of 4 mg/kg (group A, n=12) or 6 mg/kg (group B, n=12). T2* values were statistically analyzed using two-tailed paired t-tests.Results: In group A, the percentage changes from baseline to immediate post and baseline to 48 hours were 85.3% and 64.2% for the cortex and 90.8% and 64.6% for the medulla, respectively. In group B, the percentage changes from baseline to immediate post and baseline to 48 hours were 85.2% and 73.4% for the cortex and 94.5% and 74% for the medulla, respectively. This difference was significant for both groups (P
- Published
- 2014
10. Endotracheal Tubes Cleaned With a Novel Mechanism for Secretion Removal: A Randomized Controlled Clinical Study
- Author
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Gregory R. Wojtkiewicz, Christopher T Chenelle, Robert M. Kacmarek, Matthias Nahrendorf, John G. Thomas, Riccardo Pinciroli, Cristina Mietto, Lynn Bry, Massimiliano Pirrone, Lorenzo Berra, Annop Piriyapatsom, Pinciroli, R, Mietto, C, Piriyapatsom, A, Chenelle, C, Thomas, J, Pirrone, M, Bry, L, Wojtkiewicz, G, Nahrendorf, M, Kacmarek, R, and Berra, L
- Subjects
Pulmonary and Respiratory Medicine ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Lumen (anatomy) ,Suction ,Critical Care and Intensive Care Medicine ,VAP (Ventilator-associated pneumonia) ,03 medical and health sciences ,0302 clinical medicine ,Occlusion ,Intubation, Intratracheal ,Medicine ,Intubation ,Humans ,Respiratory system ,Aged ,Equipment Safety ,business.industry ,Biofilm ,Pneumonia, Ventilator-Associated ,030208 emergency & critical care medicine ,General Medicine ,Airway obstruction ,Middle Aged ,medicine.disease ,Mucus ,Ventilation ,Surgery ,030228 respiratory system ,Biofilms ,Breathing ,Equipment Contamination ,Female ,Airway ,business ,Follow-Up Studies - Abstract
INTRODUCTION: Intubation compromises mucus clearance, allowing secretions to accumulate inside the endotracheal tube (ETT). The purpose of this trial was to evaluate a novel device for ETT cleaning. We hypothesized that its routine use would reduce tube occlusion due to mucus accumulation, while decreasing airway bacterial colonization. METHODS: Subjects were randomized to either the use of the device every 8 h, or the institutional standard of care (blind tracheal suction) only. ETTs were collected at extubation and analyzed with high-resolution computed tomography (HRCT) for quantification of mucus volume. Microbiological testing was performed on biofilm samples. Vital signs and ventilatory settings were collected at the bedside. In-hospital follow-up was conducted, and a final evaluation survey was completed by respiratory therapists. RESULTS: Seventy-four subjects expected to remain intubated for longer than 48 h were enrolled (77 ETTs, 37 treatment vs 40 controls). Treated tubes showed reduced mucus accumulation (0.56 ± 0.12 vs 0.71 ± 0.28 mL; P = .004) and reduced occlusion (6.3 ± 1.7 vs 8.9 ± 7.6%; P = .039). The HRCT slice showing the narrowest lumen within each ETT exhibited less occlusion in cleaned tubes (10.6 ± 8.0 vs 17.7 ± 13.4%, 95% CI: 2–12.1; P = .007). Data on microbial colonization showed a trend in the treatment group toward a reduced ETT-based biomass of bacteria known to cause ventilator-associated pneumonia. No adverse events were reported. The staff was satisfied by the overall safety and feasibility of the device. CONCLUSION: The endOclear is a safe and effective device. It prevents luminal occlusion, thereby better preserving ETT nominal function.
- Published
- 2016
11. Tracheal tube obstruction in mechanically ventilated patients assessed by high-resolution computed tomography
- Author
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Matthias Nahrendorf, John G. Thomas, Mary L. Delaney, Robert M. Kacmarek, Cristina Mietto, Jessica Truelove, Jeanne B. Ackman, Lynn Bry, Gregory R. Wojtkiewicz, Andrea Du Bois, Lorenzo Berra, Annop Piriyapatsom, Riccardo Pinciroli, Mietto, C, Pinciroli, R, Piriyapatsom, A, Thomas, J, Bry, L, Delaney, M, Du Bois, A, Truelove, J, Ackman, J, Wojtkiewicz, G, Nahrendorf, M, Kacmarek, R, and Berra, L
- Subjects
Models, Anatomic ,High-resolution computed tomography ,medicine.medical_specialty ,medicine.medical_treatment ,Critical Illness ,Lumen (anatomy) ,Tracheal tube ,intubation ,biofilm ,Airway resistance ,medicine ,Intubation, Intratracheal ,Intubation ,Humans ,VAP (ventialtor-associated pneumonia) ,airway obstruction ,Mechanical ventilation ,Air Pressure ,medicine.diagnostic_test ,Anatomy, Cross-Sectional ,business.industry ,ventilation ,Airway Resistance ,Tracheal intubation ,Airway obstruction ,medicine.disease ,Respiration, Artificial ,Trachea ,Anesthesiology and Pain Medicine ,Airway Extubation ,Equipment Contamination ,Equipment Failure ,Radiology ,Nuclear medicine ,business ,Tomography, X-Ray Computed - Abstract
Background: Tracheal intubation compromises mucus clearance and secretions accumulate inside the tracheal tube (TT). The aim of this study was to evaluate with a novel methodology TT luminal obstruction in critically ill patients. Methods: This was a three-phase study: (1) the authors collected 20 TTs at extubation. High-resolution computed tomography (CT) was performed to determine cross-sectional area (CSA) and mucus distribution within the TT; (2) five TTs partially filled with silicone were used to correlate high-resolution CT results and increased airflow resistance; and (3) 20 chest CT scans of intubated patients were reviewed for detection of secretions in ventilated patients’ TT. Results: Postextubation TTs showed a maximum CSA reduction of (mean ± SD) 24.9 ± 3.9% (range 3.3 to 71.2%) after a median intubation of 4.5 (interquartile range 2.5 to 6.5) days. CSA progressively decreased from oral to lung end of used TTs. The luminal volume of air was different between used and new TTs for all internal diameters (P < 0.01 for new vs. used TTs for all studied internal diameters). The relationship between pressure drop and increasing airflow rates was nonlinear and depended on minimum CSA available to ventilation. Weak correlation was found between TT occlusion and days of intubation (R2 = 0.352, P = 0.006). With standard clinical chest CT scans, 6 of 20 TTs showed measurable secretions with a CSA reduction of 24.0 ± 3.9%. Conclusions: TT luminal narrowing is a common finding and correlates with increased airflow resistance. The authors propose high-resolution CT as a novel technique to visualize and quantify secretions collected within the TT lumen.
- Published
- 2014
12. Ex Vivo Machine Perfusion as a Platform for Lentiviral Gene Delivery in Rat Livers.
- Author
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Uygun K, von Reiterdank IF, Mojoudi M, Bento R, Taggart M, Dinicu A, Wojtkiewicz G, Coert J, van der Molen AM, Weissleder R, and Parekkadan B
- Abstract
Developing new strategies for local monitoring and delivery of immunosuppression is critical to making allografts safer and more accessible. Ex vivo genetic modification of grafts using machine perfusion presents a promising approach to improve graft function and modulate immune responses while minimizing risks of off-target effects and systemic immunogenicity in vivo. This proof-of-concept study demonstrates the feasibility of using normothermic machine perfusion (NMP) to mimic in vitro conditions for effective gene delivery. In this study, lentiviral vectors carrying biosensor constructs with Gaussia Luciferase (GLuc) were introduced to rodent livers during a 72-hour perfusion period, with a targeted delivery of 3 × 10
7 infection units (IU). Following the initial 24-hour exposure required for viral transduction, an additional 48 hours was necessary to observe gene expression, analogous to in vitro benchmarks. The perfused livers displayed significantly increased luminescence compared to controls, illustrating successful genetic modification. These findings validate the ex vivo use of lentiviral particles in a rodent liver model and lay the groundwork for a broad range of applications through genetic manipulation of organ systems. Future studies will focus on refining this technology to enhance precision in gene expression and explore its implications for clinical transplantation., Competing Interests: Declarations Competing interest statement I.F.R., R.B., B.P., and K.U. have patent applications relevant to this field. Competing interests for Massachusetts General Hospital investigators are managed by the MGH and MGB in accordance with their conflict-of-interest policies. M.M., M.T., A.D., G.W., A.M.M., J.C. and R.W. have no competing interests.- Published
- 2024
- Full Text
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13. Therapeutic Spp1 silencing in TREM2 + cardiac macrophages suppresses atrial fibrillation.
- Author
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Momin N, Pabel S, Rudra A, Kumowski N, Lee IH, Mentkowski K, Yamazoe M, Stengel L, Muse CG, Seung H, Paccalet A, Gonzalez-Correa C, Jacobs EB, Grune J, Schloss MJ, Sossalla S, Wojtkiewicz G, Iwamoto Y, McMullen P, Mitchell RN, Ellinor PT, Anderson DG, Naxerova K, Nahrendorf M, and Hulsmans M
- Abstract
Atrial fibrillation (AFib) and the risk of its lethal complications are propelled by fibrosis, which induces electrical heterogeneity and gives rise to reentry circuits. Atrial TREM2
+ macrophages secrete osteopontin (encoded by Spp1 ), a matricellular signaling protein that engenders fibrosis and AFib. Here we show that silencing Spp1 in TREM2+ cardiac macrophages with an antibody-siRNA conjugate reduces atrial fibrosis and suppresses AFib in mice, thus offering a new immunotherapy for the most common arrhythmia., Competing Interests: Competing interests: S.S. received speaker fees or honoraria from Astra Zeneca, Novartis, Berlin-Chemie, Daiichi Sankyo, Bristol Myers Squibb, Pfizer, Boehringer Ingelheim, and Lilly. P.T.E. receives sponsored research support from Bayer AG, IBM Research, Bristol Myers Squibb, Pfizer, and Novo Nordisk; he has also served on advisory boards or consulted for Bayer AG. D.G.A is a founder of oRNA Tx, Verseau Tx, Combined Tx, and Souffle Tx. M.N. has received funds or material research support from Alnylam, Biotronik, CSL Behring, GlycoMimetics, GSK, Medtronic, Novartis, and Pfizer, as well as consulting fees from Biogen, Gimv, IFM Therapeutics, Molecular Imaging, Sigilon, Verseau Therapeutics, and Bitterroot. N.M., A.R., I.L., M.J.S., D.G.A., K.N, M.N., and M.H. are inventors on U.S. Provisional Patent applications no. 63/501,286 and 63/525,135 regarding the role of and modulating stromal and immune cells in atrial disease. The other authors declare no competing interests.- Published
- 2024
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14. Optimizing animal models of autoimmune encephalitis using active immunization.
- Author
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Linnoila J, Jalali Motlagh N, Jachimiec G, Lin CJ, Küllenberg E, Wojtkiewicz G, Tanzi R, and Chen JW
- Subjects
- Mice, Female, Animals, Emulsions, Mice, Inbred C57BL, Antibodies, Receptors, N-Methyl-D-Aspartate, Vaccination, Disease Models, Animal, Encephalitis, Autoimmune Diseases of the Nervous System
- Abstract
Background and Objectives: Encephalitis is a devastating neurologic disorder with high morbidity and mortality. Autoimmune causes are roughly as common as infectious ones. N-methyl-D-aspartic acid receptor (NMDAR) encephalitis (NMDARE), characterized by serum and/or spinal fluid NMDAR antibodies, is the most common form of autoimmune encephalitis (AE). A translational rodent NMDARE model would allow for pathophysiologic studies of AE, leading to advances in the diagnosis and treatment of this debilitating neuropsychiatric disorder. The main objective of this work was to identify optimal active immunization conditions for NMDARE in mice., Methods: Female C57BL/6J mice aged 8 weeks old were injected subcutaneously with an emulsion of complete Freund's adjuvant, killed and dessicated Mycobacterium tuberculosis , and a 30 amino acid peptide flanking the NMDAR GluN1 subunit N368/G369 residue targeted by NMDARE patients' antibodies. Three different induction methods were examined using subcutaneous injection of the peptide emulsion mixture into mice in 1) the ventral surface, 2) the dorsal surface, or 3) the dorsal surface with reimmunization at 4 and 8 weeks (boosted). Mice were bled biweekly and sacrificed at 2, 4, 6, 8, and 14 weeks. Serum and CSF NMDAR antibody titer, mouse behavior, hippocampal cell surface and postsynaptic NMDAR cluster density, and brain immune cell entry and cytokine content were examined., Results: All immunized mice produced serum and CSF NMDAR antibodies, which peaked at 6 weeks in the serum and at 6 (ventral and dorsal boosted) or 8 weeks (dorsal unboosted) post-immunization in the CSF, and demonstrated decreased hippocampal NMDAR cluster density by 6 weeks post-immunization. In contrast to dorsally-immunized mice, ventrally-induced mice displayed a translationally-relevant phenotype including memory deficits and depressive behavior, changes in cerebral cytokines, and entry of T-cells into the brain at the 4-week timepoint. A similar phenotype of memory dysfunction and anxiety was seen in dorsally-immunized mice only when they were serially boosted, which also resulted in higher antibody titers., Discussion: Our study revealed induction method-dependent differences in active immunization mouse models of NMDARE disease. A novel ventrally-induced NMDARE model demonstrated characteristics of AE earlier compared to dorsally-induced animals and is likely suitable for most short-term studies. However, boosting and improving the durability of the immune response might be preferred in prolonged longitudinal studies., Competing Interests: Author JL is an expert respondent for the National Vaccine Injury Compensation Program and received research support from NIH/NINDS, the McCance and Rappaport families, and Harvard Medical School/Massachusetts General Hospital. Author C-CL received research support from NIH/NIA. Author RT received research support from the Cure Alzheimer’s Fund. Author JC receives publishing royalties from Elsevier and research support from NIH and NMSS. Author JC is a co-founder of Silverier and Einsenca. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Linnoila, Jalali Motlagh, Jachimiec, Lin, Küllenberg, Wojtkiewicz, Tanzi and Chen.)
- Published
- 2023
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15. Cerebrospinal fluid can exit into the skull bone marrow and instruct cranial hematopoiesis in mice with bacterial meningitis.
- Author
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Pulous FE, Cruz-Hernández JC, Yang C, Kaya Ζ, Paccalet A, Wojtkiewicz G, Capen D, Brown D, Wu JW, Schloss MJ, Vinegoni C, Richter D, Yamazoe M, Hulsmans M, Momin N, Grune J, Rohde D, McAlpine CS, Panizzi P, Weissleder R, Kim DE, Swirski FK, Lin CP, Moskowitz MA, and Nahrendorf M
- Subjects
- Animals, Bone Marrow, Brain blood supply, Cerebrospinal Fluid, Hematopoiesis, Mice, Skull, Glymphatic System physiology, Meningitis, Bacterial
- Abstract
Interactions between the immune and central nervous systems strongly influence brain health. Although the blood-brain barrier restricts this crosstalk, we now know that meningeal gateways through brain border tissues facilitate intersystem communication. Cerebrospinal fluid (CSF), which interfaces with the glymphatic system and thereby drains the brain's interstitial and perivascular spaces, facilitates outward signaling beyond the blood-brain barrier. In the present study, we report that CSF can exit into the skull bone marrow. Fluorescent tracers injected into the cisterna magna of mice migrate along perivascular spaces of dural blood vessels and then travel through hundreds of sub-millimeter skull channels into the calvarial marrow. During meningitis, bacteria hijack this route to invade the skull's hematopoietic niches and initiate cranial hematopoiesis ahead of remote tibial sites. As skull channels also directly provide leukocytes to meninges, the privileged sampling of brain-derived danger signals in CSF by regional marrow may have broad implications for inflammatory neurological disorders., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)
- Published
- 2022
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16. Bone marrow endothelial dysfunction promotes myeloid cell expansion in cardiovascular disease.
- Author
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Rohde D, Vandoorne K, Lee IH, Grune J, Zhang S, McAlpine CS, Schloss MJ, Nayar R, Courties G, Frodermann V, Wojtkiewicz G, Honold L, Chen Q, Schmidt S, Iwamoto Y, Sun Y, Cremer S, Hoyer FF, Iborra-Egea O, Muñoz-Guijosa C, Ji F, Zhou B, Adams RH, Wythe JD, Hidalgo J, Watanabe H, Jung Y, van der Laan AM, Piek JJ, Kfoury Y, Désogère PA, Vinegoni C, Dutta P, Sadreyev RI, Caravan P, Bayes-Genis A, Libby P, Scadden DT, Lin CP, Naxerova K, Swirski FK, and Nahrendorf M
- Subjects
- Animals, Female, Male, Mice, Atherosclerosis pathology, Atherosclerosis metabolism, Cell Proliferation, Disease Models, Animal, Endothelial Cells metabolism, Endothelial Cells pathology, Hypertension pathology, Hypertension metabolism, Hypertension physiopathology, Interleukin-6 metabolism, Interleukin-6 genetics, Leukocytosis pathology, Mice, Inbred C57BL, Mice, Knockout, Myocardial Infarction pathology, Myocardial Infarction metabolism, Myocardial Infarction genetics, Myocardial Infarction physiopathology, Vascular Remodeling physiology, Versicans genetics, Versicans metabolism, Humans, Hematopoiesis, Myeloid Cells metabolism, Myeloid Cells pathology, Vascular Endothelial Growth Factor Receptor-2 metabolism, Vascular Endothelial Growth Factor Receptor-2 genetics
- Abstract
Abnormal hematopoiesis advances cardiovascular disease by generating excess inflammatory leukocytes that attack the arteries and the heart. The bone marrow niche regulates hematopoietic stem cell proliferation and hence the systemic leukocyte pool, but whether cardiovascular disease affects the hematopoietic organ's microvasculature is unknown. Here we show that hypertension, atherosclerosis and myocardial infarction (MI) instigate endothelial dysfunction, leakage, vascular fibrosis and angiogenesis in the bone marrow, altogether leading to overproduction of inflammatory myeloid cells and systemic leukocytosis. Limiting angiogenesis with endothelial deletion of Vegfr2 (encoding vascular endothelial growth factor (VEGF) receptor 2) curbed emergency hematopoiesis after MI. We noted that bone marrow endothelial cells assumed inflammatory transcriptional phenotypes in all examined stages of cardiovascular disease. Endothelial deletion of Il6 or Vcan (encoding versican), genes shown to be highly expressed in mice with atherosclerosis or MI, reduced hematopoiesis and systemic myeloid cell numbers in these conditions. Our findings establish that cardiovascular disease remodels the vascular bone marrow niche, stimulating hematopoiesis and production of inflammatory leukocytes.
- Published
- 2022
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17. Prosaposin mediates inflammation in atherosclerosis.
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van Leent MMT, Beldman TJ, Toner YC, Lameijer MA, Rother N, Bekkering S, Teunissen AJP, Zhou X, van der Meel R, Malkus J, Nauta SA, Klein ED, Fay F, Sanchez-Gaytan BL, Pérez-Medina C, Kluza E, Ye YX, Wojtkiewicz G, Fisher EA, Swirski FK, Nahrendorf M, Zhang B, Li Y, Zhang B, Joosten LAB, Pasterkamp G, Boltjes A, Fayad ZA, Lutgens E, Netea MG, Riksen NP, Mulder WJM, and Duivenvoorden R
- Subjects
- Animals, Disease Models, Animal, Inflammation, Mice, Mice, Inbred C57BL, Mice, Knockout, ApoE, Atherosclerosis, Plaque, Atherosclerotic, Saposins therapeutic use
- Abstract
Macrophages play a central role in the pathogenesis of atherosclerosis. The inflammatory properties of these cells are dictated by their metabolism, of which the mechanistic target of rapamycin (mTOR) signaling pathway is a key regulator. Using myeloid cell-specific nanobiologics in apolipoprotein E-deficient ( Apoe
-/- ) mice, we found that targeting the mTOR and ribosomal protein S6 kinase-1 (S6K1) signaling pathways rapidly diminished plaque macrophages' inflammatory activity. By investigating transcriptome modifications, we identified Psap , a gene encoding the lysosomal protein prosaposin, as closely related with mTOR signaling. Subsequent in vitro experiments revealed that Psap inhibition suppressed both glycolysis and oxidative phosphorylation. Transplantation of Psap-/- bone marrow to low-density lipoprotein receptor knockout ( Ldlr-/- ) mice led to a reduction in atherosclerosis development and plaque inflammation. Last, we confirmed the relationship between PSAP expression and inflammation in human carotid atherosclerotic plaques. Our findings provide mechanistic insights into the development of atherosclerosis and identify prosaposin as a potential therapeutic target., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)- Published
- 2021
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18. Ibrutinib-Mediated Atrial Fibrillation Attributable to Inhibition of C-Terminal Src Kinase.
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Xiao L, Salem JE, Clauss S, Hanley A, Bapat A, Hulsmans M, Iwamoto Y, Wojtkiewicz G, Cetinbas M, Schloss MJ, Tedeschi J, Lebrun-Vignes B, Lundby A, Sadreyev RI, Moslehi J, Nahrendorf M, Ellinor PT, and Milan DJ
- Subjects
- Action Potentials drug effects, Adenine toxicity, Agammaglobulinaemia Tyrosine Kinase deficiency, Agammaglobulinaemia Tyrosine Kinase genetics, Animals, Atrial Fibrillation enzymology, Atrial Fibrillation physiopathology, CSK Tyrosine-Protein Kinase genetics, CSK Tyrosine-Protein Kinase metabolism, Databases, Genetic, Heart Atria enzymology, Heart Atria physiopathology, Humans, Mice, 129 Strain, Mice, Inbred C57BL, Mice, Inbred CBA, Mice, Knockout, Risk Assessment, Risk Factors, Adenine analogs & derivatives, Antineoplastic Agents toxicity, Atrial Fibrillation chemically induced, Atrial Function, Left drug effects, CSK Tyrosine-Protein Kinase antagonists & inhibitors, Heart Atria drug effects, Heart Rate drug effects, Piperidines toxicity, Protein Kinase Inhibitors toxicity
- Abstract
Background: Ibrutinib is a Bruton tyrosine kinase inhibitor with remarkable efficacy against B-cell cancers. Ibrutinib also increases the risk of atrial fibrillation (AF), which remains poorly understood., Methods: We performed electrophysiology studies on mice treated with ibrutinib to assess inducibility of AF. Chemoproteomic analysis of cardiac lysates identified candidate ibrutinib targets, which were further evaluated in genetic mouse models and additional pharmacological experiments. The pharmacovigilance database, VigiBase, was queried to determine whether drug inhibition of an identified candidate kinase was associated with increased reporting of AF., Results: We demonstrate that treatment of mice with ibrutinib for 4 weeks results in inducible AF, left atrial enlargement, myocardial fibrosis, and inflammation. This effect was reproduced in mice lacking Bruton tyrosine kinase, but not in mice treated with 4 weeks of acalabrutinib, a more specific Bruton tyrosine kinase inhibitor, demonstrating that AF is an off-target side effect. Chemoproteomic profiling identified a short list of candidate kinases that was narrowed by additional experimentation leaving CSK (C-terminal Src kinase) as the strongest candidate for ibrutinib-induced AF. Cardiac-specific Csk knockout in mice led to increased AF, left atrial enlargement, fibrosis, and inflammation, phenocopying ibrutinib treatment. Disproportionality analyses in VigiBase confirmed increased reporting of AF associated with kinase inhibitors blocking Csk versus non-Csk inhibitors, with a reporting odds ratio of 8.0 (95% CI, 7.3-8.7; P <0.0001)., Conclusions: These data identify Csk inhibition as the mechanism through which ibrutinib leads to AF. Registration: URL: https://ww.clinicaltrials.gov; Unique identifier: NCT03530215.
- Published
- 2020
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19. Characterization of an elastase-induced emphysema model in immune-deficient rats.
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Becerra D, Jeffs S, Wojtkiewicz G, and Ott H
- Abstract
Objectives: Emphysema affects millions of patients worldwide. Cell transplantation and tissue engineering are promising approaches for the regeneration of gas exchange tissue in vivo. A reproducible and resource-efficient animal model with relevant pathological and physiological features is critical to assess efficacy of novel therapies. Here, we share a method for rapid development of emphysema in an adaptive immune-deficient rat with <5% mortality, which is ideal for high-throughput human cell-based experimentation., Methods: Porcine pancreatic elastase (PPE) was intratracheally administered to male RNU rats. Rats were monitored for 21 days after which subjects underwent lung computed tomography (CT) scans. Rats were then weighed, intubated and mechanically ventilated to measure dynamic compliance. After sacrifice, lungs were fixed, and histological sections were quantitatively assessed for emphysematous changes., Results: A single instillation of elastase was enough to produce anatomic and physiological evidence of emphysema. Weight change for doses of 16 and 32 units PPE/100 g were significantly lower than controls (P = 0.028 and P = 0.043, respectively). Compliance values for doses of 16 and 32 units PPE/100 g were significantly higher than controls (P = 0.037 and P = 0.006, respectively). Lung hyperlucency was confirmed by CT with mean Hounsfield units for a dose of 32 units PPE/100 g being significantly lower than controls (P < 0.001). The mean linear intersect for doses of 16 and 32 units PPE/100 g were significantly higher than controls (both P < 0.001). All reported P-values are one-sided., Conclusions: We present an efficient method for emphysema development in immune-deficient rats as a tool to evaluate human biological therapeutics. Changes in dynamic compliance, histology and cross-sectional imaging recapitulate human emphysema., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)
- Published
- 2020
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20. Imaging Cardiovascular and Lung Macrophages With the Positron Emission Tomography Sensor 64 Cu-Macrin in Mice, Rabbits, and Pigs.
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Nahrendorf M, Hoyer FF, Meerwaldt AE, van Leent MMT, Senders ML, Calcagno C, Robson PM, Soultanidis G, Pérez-Medina C, Teunissen AJP, Toner YC, Ishikawa K, Fish K, Sakurai K, van Leeuwen EM, Klein ED, Sofias AM, Reiner T, Rohde D, Aguirre AD, Wojtkiewicz G, Schmidt S, Iwamoto Y, Izquierdo-Garcia D, Caravan P, Swirski FK, Weissleder R, and Mulder WJM
- Subjects
- Animals, Atherosclerosis diagnostic imaging, Atherosclerosis pathology, Disease Models, Animal, Injections, Intravenous, Lung pathology, Macrophages, Alveolar pathology, Mice, Myocardial Infarction diagnostic imaging, Myocardial Infarction pathology, Nanoparticles, Pneumonia diagnostic imaging, Pneumonia pathology, Predictive Value of Tests, Rabbits, Swine, Swine, Miniature, Time Factors, Copper Radioisotopes administration & dosage, Copper Radioisotopes pharmacokinetics, Dextrans administration & dosage, Dextrans pharmacokinetics, Heart diagnostic imaging, Lung diagnostic imaging, Macrophages pathology, Molecular Imaging, Positron Emission Tomography Computed Tomography, Radiopharmaceuticals administration & dosage, Radiopharmaceuticals pharmacokinetics
- Abstract
Background: Macrophages, innate immune cells that reside in all organs, defend the host against infection and injury. In the heart and vasculature, inflammatory macrophages also enhance tissue damage and propel cardiovascular diseases., Methods: We here use in vivo positron emission tomography (PET) imaging, flow cytometry, and confocal microscopy to evaluate quantitative noninvasive assessment of cardiac, arterial, and pulmonary macrophages using the nanotracer
64 Cu-Macrin-a 20-nm spherical dextran nanoparticle assembled from nontoxic polyglucose., Results: PET imaging using64 Cu-Macrin faithfully reported accumulation of macrophages in the heart and lung of mice with myocardial infarction, sepsis, or pneumonia. Flow cytometry and confocal microscopy detected the near-infrared fluorescent version of the nanoparticle (VT680 Macrin) primarily in tissue macrophages. In 5-day-old mice,64 Cu-Macrin PET imaging quantified physiologically more numerous cardiac macrophages. Upon intravenous administration of64 Cu-Macrin in rabbits and pigs, we detected heightened macrophage numbers in the infarcted myocardium, inflamed lung regions, and atherosclerotic plaques using a clinical PET/magnetic resonance imaging scanner. Toxicity studies in rats and human dosimetry estimates suggest that64 Cu-Macrin is safe for use in humans., Conclusions: Taken together, these results indicate64 Cu-Macrin could serve as a facile PET nanotracer to survey spatiotemporal macrophage dynamics during various physiological and pathological conditions.64 Cu-Macrin PET imaging could stage inflammatory cardiovascular disease activity, assist disease management, and serve as an imaging biomarker for emerging macrophage-targeted therapeutics.- Published
- 2020
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21. Diminished Reactive Hematopoiesis and Cardiac Inflammation in a Mouse Model of Recurrent Myocardial Infarction.
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Cremer S, Schloss MJ, Vinegoni C, Foy BH, Zhang S, Rohde D, Hulsmans M, Fumene Feruglio P, Schmidt S, Wojtkiewicz G, Higgins JM, Weissleder R, Swirski FK, and Nahrendorf M
- Subjects
- Aged, Aged, 80 and over, Animals, Anterior Wall Myocardial Infarction blood, Female, Humans, Leukocytosis, Macrophages physiology, Male, Mice, Middle Aged, Parabiosis, Recurrence, Retrospective Studies, Anterior Wall Myocardial Infarction immunology, Disease Models, Animal, Hematopoiesis
- Abstract
Background: Recurrent myocardial infarction (MI) is common in patients with coronary artery disease and is associated with high mortality. Long-term reprogramming of myeloid progenitors occurs in response to inflammatory stimuli and alters the organism's response to secondary inflammatory challenges., Objectives: This study examined the effect of recurrent MI on bone marrow response and cardiac inflammation., Methods: The investigators developed a surgical mouse model in which 2 subsequent MIs affected different left ventricular regions in the same mouse. Recurrent MI was induced by ligating the left circumflex artery followed by the left anterior descending coronary artery branch. The study characterized the resulting ischemia by whole-heart fluorescent coronary angiography after optical organ clearing and by cardiac magnetic resonance imaging., Results: A first MI-induced bone marrow "memory" via a circulating signal, reducing hematopoietic maintenance factor expression in bone marrow macrophages. This dampened the organism's reaction to subsequent events. Despite a similar extent of injury according to troponin levels, recurrent MI caused reduced emergency hematopoiesis and less leukocytosis than a first MI. Consequently, fewer leukocytes migrated to the ischemic myocardium. The hematopoietic response to lipopolysaccharide was also mitigated after a previous MI. The increase of white blood count in 28 patients was lower after recurrent MI compared with their first MI., Conclusions: The data suggested that hematopoietic and innate immune responses are shaped by a preceding MI., (Copyright © 2020 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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22. Tissue-Specific Macrophage Responses to Remote Injury Impact the Outcome of Subsequent Local Immune Challenge.
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Hoyer FF, Naxerova K, Schloss MJ, Hulsmans M, Nair AV, Dutta P, Calcagno DM, Herisson F, Anzai A, Sun Y, Wojtkiewicz G, Rohde D, Frodermann V, Vandoorne K, Courties G, Iwamoto Y, Garris CS, Williams DL, Breton S, Brown D, Whalen M, Libby P, Pittet MJ, King KR, Weissleder R, Swirski FK, and Nahrendorf M
- Subjects
- Animals, Biomarkers, Cell Count, ErbB Receptors metabolism, Gene Expression Profiling, Gene Expression Regulation, Gene Regulatory Networks, Ischemia etiology, Ischemia metabolism, Macrophages, Alveolar immunology, Macrophages, Alveolar metabolism, Mice, Muscle Cells immunology, Muscle Cells metabolism, Myocardial Infarction etiology, Myocardial Infarction metabolism, Organ Specificity genetics, Organ Specificity immunology, Pneumonia etiology, Pneumonia metabolism, Pneumonia pathology, Disease Susceptibility immunology, Macrophages immunology, Macrophages metabolism
- Abstract
Myocardial infarction, stroke, and sepsis trigger systemic inflammation and organism-wide complications that are difficult to manage. Here, we examined the contribution of macrophages residing in vital organs to the systemic response after these injuries. We generated a comprehensive catalog of changes in macrophage number, origin, and gene expression in the heart, brain, liver, kidney, and lung of mice with myocardial infarction, stroke, or sepsis. Predominantly fueled by heightened local proliferation, tissue macrophage numbers increased systemically. Macrophages in the same organ responded similarly to different injuries by altering expression of tissue-specific gene sets. Preceding myocardial infarction improved survival of subsequent pneumonia due to enhanced bacterial clearance, which was caused by IFNɣ priming of alveolar macrophages. Conversely, EGF receptor signaling in macrophages exacerbated inflammatory lung injury. Our data suggest that local injury activates macrophages in remote organs and that targeting macrophages could improve resilience against systemic complications following myocardial infarction, stroke, and sepsis., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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23. Stage-dependent differential effects of interleukin-1 isoforms on experimental atherosclerosis.
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Vromman A, Ruvkun V, Shvartz E, Wojtkiewicz G, Santos Masson G, Tesmenitsky Y, Folco E, Gram H, Nahrendorf M, Swirski FK, Sukhova GK, and Libby P
- Subjects
- Animals, Arteritis metabolism, Disease Models, Animal, Interleukin-1alpha antagonists & inhibitors, Interleukin-1alpha blood, Interleukin-1beta antagonists & inhibitors, Interleukin-1beta blood, Male, Mice, Mice, Knockout, Monocytes metabolism, Plaque, Atherosclerotic metabolism, Atherosclerosis metabolism, Interleukin-1alpha metabolism, Interleukin-1beta metabolism
- Abstract
Aims: Targeting interleukin-1 (IL-1) represents a novel therapeutic approach to atherosclerosis. CANTOS demonstrated the benefits of IL-1β neutralization in patients post-myocardial infarction with residual inflammatory risk. Yet, some mouse data have shown a prominent role of IL-1α rather than IL-1β in atherosclerosis, or even a deleterious effect of IL-1 on outward arterial remodelling in atherosclerosis-susceptible mice. To shed light on these disparate results, this study investigated the effect of neutralizing IL-1α or/and IL-1β isoforms starting either early in atherogenesis or later in ApoE-/- mice with established atheroma., Methods and Results: The neutralization of IL-1α or of both IL-1 isoforms impaired outward remodelling during early atherogenesis as assessed by micro-computed tomographic and histologic assessment. In contrast, the neutralization of IL-1β did not impair outward remodelling either during early atherogenesis or in mice with established lesions. Interleukin-1β inhibition promoted a slant of blood monocytes towards a less inflammatory state during atherogenesis, reduced the size of established atheromata, and increased plasma levels of IL-10 without limiting outward remodelling of brachiocephalic arteries., Conclusion: This study established a pivotal role for IL-1α in the remodelling of arteries during early experimental atherogenesis, whereas IL-1β drives inflammation during atherogenesis and the evolution of advanced atheroma in mice., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2019. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2019
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24. Imaging the Vascular Bone Marrow Niche During Inflammatory Stress.
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Vandoorne K, Rohde D, Kim HY, Courties G, Wojtkiewicz G, Honold L, Hoyer FF, Frodermann V, Nayar R, Herisson F, Jung Y, Désogère PA, Vinegoni C, Caravan P, Weissleder R, Sosnovik DE, Lin CP, Swirski FK, and Nahrendorf M
- Subjects
- Animals, Bone Marrow pathology, Endothelial Progenitor Cells cytology, Female, Inflammation diagnostic imaging, Integrin alphaVbeta3 metabolism, Lipopolysaccharides toxicity, Mice, Mice, Inbred C57BL, Multimodal Imaging methods, Bone Marrow diagnostic imaging, Magnetic Resonance Imaging methods, Positron-Emission Tomography methods, Stem Cell Niche, Stress, Physiological
- Abstract
Rationale: Inflammatory stress induced by exposure to bacterial lipopolysaccharide causes hematopoietic stem cell expansion in the bone marrow niche, generating a cellular immune response. As an integral component of the hematopoietic stem cell niche, the bone marrow vasculature regulates the production and release of blood leukocytes, which protect the host against infection but also fuel inflammatory diseases., Objective: We aimed to develop imaging tools to explore vascular changes in the bone marrow niche during acute inflammation., Methods and Results: Using the TLR (Toll-like receptor) ligand lipopolysaccharide as a prototypical danger signal, we applied multiparametric, multimodality and multiscale imaging to characterize how the bone marrow vasculature adapts when hematopoiesis boosts leukocyte supply. In response to lipopolysaccharide, ex vivo flow cytometry and histology showed vascular changes to the bone marrow niche. Specifically, proliferating endothelial cells gave rise to new vasculature in the bone marrow during hypoxic conditions. We studied these vascular changes with complementary intravital microscopy and positron emission tomography/magnetic resonance imaging. Fluorescence and positron emission tomography integrin αVβ3 imaging signal increased during lipopolysaccharide-induced vascular remodeling. Vascular leakiness, quantified by albumin-based in vivo microscopy and magnetic resonance imaging, rose when neutrophils departed and hematopoietic stem and progenitor cells proliferated more vigorously., Conclusions: Introducing a tool set to image bone marrow either with cellular resolution or noninvasively within the entire skeleton, this work sheds light on angiogenic responses that accompany emergency hematopoiesis. Understanding and monitoring bone marrow vasculature may provide a key to unlock therapeutic targets regulating systemic inflammation.
- Published
- 2018
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25. Author Correction: Efficacy and safety assessment of a TRAF6-targeted nanoimmunotherapy in atherosclerotic mice and non-human primates.
- Author
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Lameijer M, Binderup T, van Leent MMT, Senders ML, Fay F, Malkus J, Sanchez-Gaytan BL, Teunissen AJP, Karakatsanis N, Robson P, Zhou X, Ye Y, Wojtkiewicz G, Tang J, Seijkens TTP, Kroon J, Stroes ESG, Kjaer A, Ochando J, Reiner T, Pérez-Medina C, Calcagno C, Fisher EA, Zhang B, Temel RE, Swirski FK, Nahrendorf M, Fayad ZA, Lutgens E, Mulder WJM, and Duivenvoorden R
- Abstract
In the version of this Article originally published, the surname of the author Edward A. Fisher was spelt incorrectly as 'Fischer'. This has now been corrected.
- Published
- 2018
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26. Efficacy and safety assessment of a TRAF6-targeted nanoimmunotherapy in atherosclerotic mice and non-human primates.
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Lameijer M, Binderup T, van Leent MMT, Senders ML, Fay F, Malkus J, Sanchez-Gaytan BL, Teunissen AJP, Karakatsanis N, Robson P, Zhou X, Ye Y, Wojtkiewicz G, Tang J, Seijkens TTP, Kroon J, Stroes ESG, Kjaer A, Ochando J, Reiner T, Pérez-Medina C, Calcagno C, Fisher EA, Zhang B, Temel RE, Swirski FK, Nahrendorf M, Fayad ZA, Lutgens E, Mulder WJM, and Duivenvoorden R
- Subjects
- Animals, Atherosclerosis diagnostic imaging, Atherosclerosis pathology, CD40 Antigens metabolism, CD40 Ligand metabolism, Disease Models, Animal, Female, Macaca fascicularis, Macrophages immunology, Male, Mice, Mice, Transgenic, Monocytes immunology, TNF Receptor-Associated Factor 6 chemistry, Tissue Distribution, Atherosclerosis therapy, Immunotherapy methods, Nanomedicine methods, TNF Receptor-Associated Factor 6 metabolism
- Abstract
Macrophage accumulation in atherosclerosis is directly linked to the destabilization and rupture of plaque, causing acute atherothrombotic events. Circulating monocytes enter the plaque and differentiate into macrophages, where they are activated by CD4
+ T lymphocytes through CD40-CD40 ligand signalling. Here, we report the development and multiparametric evaluation of a nanoimmunotherapy that moderates CD40-CD40 ligand signalling in monocytes and macrophages by blocking the interaction between CD40 and tumour necrosis factor receptor-associated factor 6 (TRAF6). We evaluated the biodistribution characteristics of the nanoimmunotherapy in apolipoprotein E-deficient (Apoe-/- ) mice and in non-human primates by in vivo positron-emission tomography imaging. In Apoe-/- mice, a 1-week nanoimmunotherapy treatment regimen achieved significant anti-inflammatory effects, which was due to the impaired migration capacity of monocytes, as established by a transcriptome analysis. The rapid reduction of plaque inflammation by the TRAF6-targeted nanoimmunotherapy and its favourable toxicity profiles in both mice and non-human primates highlights the translational potential of this strategy for the treatment of atherosclerosis.- Published
- 2018
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27. Cardiac macrophages promote diastolic dysfunction.
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Hulsmans M, Sager HB, Roh JD, Valero-Muñoz M, Houstis NE, Iwamoto Y, Sun Y, Wilson RM, Wojtkiewicz G, Tricot B, Osborne MT, Hung J, Vinegoni C, Naxerova K, Sosnovik DE, Zile MR, Bradshaw AD, Liao R, Tawakol A, Weissleder R, Rosenzweig A, Swirski FK, Sam F, and Nahrendorf M
- Subjects
- Adult, Aged, Aging pathology, Aging physiology, Animals, Female, Fibroblasts pathology, Fibroblasts physiology, Heart Failure pathology, Heart Failure physiopathology, Hematopoiesis, Homeostasis, Humans, Hypertension pathology, Hypertension physiopathology, Interleukin-10 deficiency, Interleukin-10 genetics, Interleukin-10 physiology, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Middle Aged, Monocytes pathology, Monocytes physiology, Stroke Volume physiology, Diastole physiology, Heart physiopathology, Macrophages pathology, Macrophages physiology, Myocardium pathology
- Abstract
Macrophages populate the healthy myocardium and, depending on their phenotype, may contribute to tissue homeostasis or disease. Their origin and role in diastolic dysfunction, a hallmark of cardiac aging and heart failure with preserved ejection fraction, remain unclear. Here we show that cardiac macrophages expand in humans and mice with diastolic dysfunction, which in mice was induced by either hypertension or advanced age. A higher murine myocardial macrophage density results from monocyte recruitment and increased hematopoiesis in bone marrow and spleen. In humans, we observed a parallel constellation of hematopoietic activation: circulating myeloid cells are more frequent, and splenic
18 F-FDG PET/CT imaging signal correlates with echocardiographic indices of diastolic dysfunction. While diastolic dysfunction develops, cardiac macrophages produce IL-10, activate fibroblasts, and stimulate collagen deposition, leading to impaired myocardial relaxation and increased myocardial stiffness. Deletion of IL-10 in macrophages improves diastolic function. These data imply expansion and phenotypic changes of cardiac macrophages as therapeutic targets for cardiac fibrosis leading to diastolic dysfunction., (© 2018 Hulsmans et al.)- Published
- 2018
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28. Molecular MR Imaging of Myeloperoxidase Distinguishes Steatosis from Steatohepatitis in Nonalcoholic Fatty Liver Disease.
- Author
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Pulli B, Wojtkiewicz G, Iwamoto Y, Ali M, Zeller MW, Bure L, Wang C, Choi Y, Masia R, Guimaraes AR, Corey KE, and Chen JW
- Subjects
- Adult, Animals, Biopsy, Contrast Media administration & dosage, Diagnosis, Differential, Disease Models, Animal, Female, Gadolinium DTPA administration & dosage, Humans, Immunoenzyme Techniques, Mice, Middle Aged, Oxidative Stress, Fatty Liver diagnostic imaging, Fatty Liver enzymology, Magnetic Resonance Imaging methods, Molecular Imaging methods, Non-alcoholic Fatty Liver Disease diagnostic imaging, Non-alcoholic Fatty Liver Disease enzymology, Peroxidase administration & dosage
- Abstract
Purpose To test whether MPO-Gd, an activatable molecular magnetic resonance (MR) imaging agent specific for myeloperoxidase (MPO) activity, could detect MPO activity in nonalcoholic steatohepatitis (NASH) mouse models and human liver biopsy samples. Materials and Methods In this study, 20 leptin receptor-deficient and three MPO knockout mice were injected with endotoxin (lipopolysaccharide) or fed a methionine and choline-deficient (MCD) diet to induce experimental NASH and underwent MR imaging with MPO-Gd. Saline-injected and control diet-fed leptin receptor-deficient mice were used as respective controls. MPO protein and activity measurements and histologic analyses were performed. Eleven human liver biopsy samples underwent MPO-Gd-enhanced MR imaging ex vivo and subsequent histologic evaluation. Results were compared with Student t test or Mann-Whitney U test. Results With endotoxin, a significantly increased contrast-to-noise ratio (CNR) was found compared with sham (mean CNR, 1.81 [95% confidence interval {CI}: 1.53, 2.10] vs 1.02 [95% CI: 0.89, 1.14]; P = .03) at MPO-Gd MR imaging. In the diet-induced NASH model, an increased CNR was also found compared with sham mice (mean CNR, 1.33 [95% CI: 1.27, 1.40] vs 0.98 [95% CI: 0.83, 1.12]; P = .008). Conversely, CNR remained at baseline in NASH mice imaged with gadopentetate dimeglumine and in MPO knockout NASH mice with MPO-Gd, which proves specificity of MPO-Gd. Ex vivo molecular MR imaging of liver biopsy samples from NASH and control patients confirmed results from animal studies (mean CNR for NASH vs control patients, 2.61 [95% CI: 1.48, 3.74] vs 1.29 [95% CI: 1.06, 1.52]; P = .004). Conclusion MPO-Gd showed elevated MPO activity in NAFLD mouse models and human liver biopsy samples.
© RSNA, 2017 Online supplemental material is available for this article. An earlier incorrect version of this article appeared online. This article was corrected on April 6, 2017.- Published
- 2017
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29. Spinal Cord Inflammation: Molecular Imaging after Thoracic Aortic Ischemia Reperfusion Injury.
- Author
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Albadawi H, Chen JW, Oklu R, Wu Y, Wojtkiewicz G, Pulli B, Milner JD, Cambria RP, and Watkins MT
- Subjects
- Animals, Aorta, Thoracic injuries, Biomarkers blood, Cytokines blood, Enzyme-Linked Immunosorbent Assay, Flow Cytometry, Immunohistochemistry, Interleukin-6 blood, Interleukin-8 blood, Magnetic Resonance Imaging, Mice, Mice, Inbred C57BL, Myelitis physiopathology, Peroxidase blood, Positron Emission Tomography Computed Tomography, Reperfusion Injury physiopathology, Aorta, Thoracic diagnostic imaging, Molecular Imaging, Myelitis diagnostic imaging, Reperfusion Injury diagnostic imaging
- Abstract
Purpose To evaluate whether noninvasive molecular imaging technologies targeting myeloperoxidase (MPO) can reveal early inflammation associated with spinal cord injury after thoracic aortic ischemia-reperfusion (TAR) in mice. Materials and Methods The study was approved by the institutional animal care and use committee. C57BL6 mice that were 8-10 weeks old underwent TAR (n = 55) or sham (n = 26) surgery. Magnetic resonance (MR) imaging (n = 6) or single photon emission computed tomography (SPECT)/computed tomography (CT) (n = 15) studies targeting MPO activity were performed after intravenous injection of MPO sensors (bis-5-hydroxytryptamide-tetraazacyclododecane [HT]-diethyneletriaminepentaacetic acid [DTPA]-gadolinium or indium 111-bis-5-HT-DTPA, respectively). Immunohistochemistry and flow cytometry were used to identify myeloid cells and neuronal loss. Proinflammatory cytokines, keratinocyte chemoattractant (KC), and interleukin 6 (IL-6) were measured with enzyme-linked immunosorbent assay. Statistical analyses were performed by using nonparametric tests and the Pearson correlation coefficient. P < .05 was considered to indicate a significant difference. Results Myeloid cells infiltrated into the injured cord at 6 and 24 hours after TAR. MR imaging confirmed the presence of ischemic lesions associated with mild MPO-mediated enhancement in the thoracolumbar spine at 24 hours compared with the sham procedure. SPECT/CT imaging of MPO activity showed marked MPO-sensor retention at 6 hours (P = .003) that continued to increase at 24 hours after TAR (P = .0001). The number of motor neurons decreased substantially at 24 hours after TAR (P < .01), which correlated inversely with in vivo inflammatory changes detected at molecular imaging (r = 0.64, P = .0099). MPO was primarily secreted by neutrophils, followed by lymphocyte antigen 6 complex
high monocytes and/or macrophages. There were corresponding increased levels of proinflammatory cytokines KC (P = .0001) and IL-6 (P = .0001) that mirrored changes in MPO activity. Conclusion MPO is a suitable imaging biomarker for identifying and tracking inflammatory damage in the spinal cord after TAR in a mouse model.© RSNA, 2016 Online supplemental material is available for this article.- Published
- 2017
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30. Immunogenic Chemotherapy Sensitizes Tumors to Checkpoint Blockade Therapy.
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Pfirschke C, Engblom C, Rickelt S, Cortez-Retamozo V, Garris C, Pucci F, Yamazaki T, Poirier-Colame V, Newton A, Redouane Y, Lin YJ, Wojtkiewicz G, Iwamoto Y, Mino-Kenudson M, Huynh TG, Hynes RO, Freeman GJ, Kroemer G, Zitvogel L, Weissleder R, and Pittet MJ
- Subjects
- Adenocarcinoma immunology, Animals, Cell Line, Tumor, Central Nervous System Sensitization drug effects, Cyclophosphamide administration & dosage, Disease Models, Animal, Drug Therapy methods, Genes, cdc drug effects, Humans, Immunity, Innate, Lung Neoplasms immunology, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Mice, Knockout, Organoplatinum Compounds administration & dosage, Oxaliplatin, Toll-Like Receptor 4 metabolism, Adenocarcinoma therapy, CD8-Positive T-Lymphocytes drug effects, Immunotherapy methods, Lung Neoplasms therapy, Lymphocytes, Tumor-Infiltrating drug effects
- Abstract
Checkpoint blockade immunotherapies can be extraordinarily effective, but might benefit only the minority of patients whose tumors are pre-infiltrated by T cells. Here, using lung adenocarcinoma mouse models, including genetic models, we show that autochthonous tumors that lacked T cell infiltration and resisted current treatment options could be successfully sensitized to host antitumor T cell immunity when appropriately selected immunogenic drugs (e.g., oxaliplatin combined with cyclophosphamide for treatment against tumors expressing oncogenic Kras and lacking Trp53) were used. The antitumor response was triggered by direct drug actions on tumor cells, relied on innate immune sensing through toll-like receptor 4 signaling, and ultimately depended on CD8(+) T cell antitumor immunity. Furthermore, instigating tumor infiltration by T cells sensitized tumors to checkpoint inhibition and controlled cancer durably. These findings indicate that the proportion of cancers responding to checkpoint therapy can be feasibly and substantially expanded by combining checkpoint blockade with immunogenic drugs., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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31. Multimodal targeted high relaxivity thermosensitive liposome for in vivo imaging.
- Author
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Kuijten MM, Hannah Degeling M, Chen JW, Wojtkiewicz G, Waterman P, Weissleder R, Azzi J, Nicolay K, and Tannous BA
- Subjects
- Animals, Biotin chemistry, Biotin metabolism, Brain Neoplasms diagnosis, Brain Neoplasms metabolism, Cell Line, Tumor, Contrast Media chemistry, Contrast Media pharmacokinetics, ErbB Receptors genetics, ErbB Receptors metabolism, Gadolinium DTPA chemistry, Gadolinium DTPA pharmacokinetics, Gene Expression, Glioma diagnosis, Glioma metabolism, Green Fluorescent Proteins genetics, Green Fluorescent Proteins metabolism, Heterocyclic Compounds chemistry, Humans, Injections, Subcutaneous, Lipid Bilayers chemistry, Lipid Bilayers pharmacokinetics, Liposomes chemistry, Mice, Mice, Nude, Neoplasm Transplantation, Organometallic Compounds chemistry, Protein Binding, Rhodamines chemistry, Streptavidin chemistry, Streptavidin metabolism, Temperature, Brain Neoplasms pathology, Glioma pathology, Heterocyclic Compounds pharmacokinetics, Liposomes pharmacokinetics, Magnetic Resonance Imaging methods, Optical Imaging methods, Organometallic Compounds pharmacokinetics
- Abstract
Liposomes are spherical, self-closed structures formed by lipid bilayers that can encapsulate drugs and/or imaging agents in their hydrophilic core or within their membrane moiety, making them suitable delivery vehicles. We have synthesized a new liposome containing gadolinium-DOTA lipid bilayer, as a targeting multimodal molecular imaging agent for magnetic resonance and optical imaging. We showed that this liposome has a much higher molar relaxivities r1 and r2 compared to a more conventional liposome containing gadolinium-DTPA-BSA lipid. By incorporating both gadolinium and rhodamine in the lipid bilayer as well as biotin on its surface, we used this agent for multimodal imaging and targeting of tumors through the strong biotin-streptavidin interaction. Since this new liposome is thermosensitive, it can be used for ultrasound-mediated drug delivery at specific sites, such as tumors, and can be guided by magnetic resonance imaging.
- Published
- 2015
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32. Predicting therapeutic nanomedicine efficacy using a companion magnetic resonance imaging nanoparticle.
- Author
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Miller MA, Gadde S, Pfirschke C, Engblom C, Sprachman MM, Kohler RH, Yang KS, Laughney AM, Wojtkiewicz G, Kamaly N, Bhonagiri S, Pittet MJ, Farokhzad OC, and Weissleder R
- Subjects
- Animals, Antineoplastic Agents, Phytogenic chemistry, Antineoplastic Agents, Phytogenic metabolism, Cell Line, Tumor, Chemistry, Pharmaceutical, DNA Damage, Disease Progression, Female, Ferrosoferric Oxide chemistry, Fibrosarcoma genetics, Fibrosarcoma metabolism, Fibrosarcoma pathology, Humans, Macrophages metabolism, Mice, Inbred BALB C, Mice, Inbred C57BL, Mice, Nude, Mice, Transgenic, Ovarian Neoplasms genetics, Ovarian Neoplasms metabolism, Ovarian Neoplasms pathology, Paclitaxel chemistry, Paclitaxel metabolism, Particle Size, Polyethylene Glycols chemistry, Polyglactin 910 chemistry, Predictive Value of Tests, Time Factors, Tissue Distribution, Tumor Microenvironment, Xenograft Model Antitumor Assays, Antineoplastic Agents, Phytogenic administration & dosage, Ferrosoferric Oxide metabolism, Fibrosarcoma drug therapy, Magnetic Resonance Imaging methods, Magnetics methods, Nanomedicine methods, Nanoparticles, Ovarian Neoplasms drug therapy, Paclitaxel administration & dosage, Polyethylene Glycols metabolism, Polyglactin 910 metabolism
- Abstract
Therapeutic nanoparticles (TNPs) have shown heterogeneous responses in human clinical trials, raising questions of whether imaging should be used to identify patients with a higher likelihood of NP accumulation and thus therapeutic response. Despite extensive debate about the enhanced permeability and retention (EPR) effect in tumors, it is increasingly clear that EPR is extremely variable; yet, little experimental data exist to predict the clinical utility of EPR and its influence on TNP efficacy. We hypothesized that a 30-nm magnetic NP (MNP) in clinical use could predict colocalization of TNPs by magnetic resonance imaging (MRI). To this end, we performed single-cell resolution imaging of fluorescently labeled MNPs and TNPs and studied their intratumoral distribution in mice. MNPs circulated in the tumor microvasculature and demonstrated sustained uptake into cells of the tumor microenvironment within minutes. MNPs could predictably demonstrate areas of colocalization for a model TNP, poly(d,l-lactic-co-glycolic acid)-b-polyethylene glycol (PLGA-PEG), within the tumor microenvironment with >85% accuracy and circulating within the microvasculature with >95% accuracy, despite their markedly different sizes and compositions. Computational analysis of NP transport enabled predictive modeling of TNP distribution based on imaging data and identified key parameters governing intratumoral NP accumulation and macrophage uptake. Finally, MRI accurately predicted initial treatment response and drug accumulation in a preclinical efficacy study using a paclitaxel-encapsulated NP in tumor-bearing mice. These approaches yield valuable insight into the in vivo kinetics of NP distribution and suggest that clinically relevant imaging modalities and agents can be used to select patients with high EPR for treatment with TNPs., (Copyright © 2015, American Association for the Advancement of Science.)
- Published
- 2015
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33. Myocardial Infarction Activates CCR2(+) Hematopoietic Stem and Progenitor Cells.
- Author
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Dutta P, Sager HB, Stengel KR, Naxerova K, Courties G, Saez B, Silberstein L, Heidt T, Sebas M, Sun Y, Wojtkiewicz G, Feruglio PF, King K, Baker JN, van der Laan AM, Borodovsky A, Fitzgerald K, Hulsmans M, Hoyer F, Iwamoto Y, Vinegoni C, Brown D, Di Carli M, Libby P, Hiebert SW, Scadden DT, Swirski FK, Weissleder R, and Nahrendorf M
- Subjects
- Animals, Cell Movement genetics, Cells, Cultured, Mice, Inbred C57BL, Mice, Knockout, Mice, Mutant Strains, Models, Animal, Myelopoiesis genetics, Myocardial Infarction surgery, Nuclear Proteins genetics, RNA, Small Interfering genetics, Receptors, CCR2 genetics, Repressor Proteins, Transcription Factors genetics, Wound Healing genetics, Hematopoietic Stem Cells physiology, Macrophages physiology, Monocytes physiology, Myeloid Cells physiology, Myocardial Infarction immunology, Nuclear Proteins metabolism, Receptors, CCR2 metabolism, Transcription Factors metabolism
- Abstract
Following myocardial infarction (MI), myeloid cells derived from the hematopoietic system drive a sharp increase in systemic leukocyte levels that correlates closely with mortality. The origin of these myeloid cells, and the response of hematopoietic stem and progenitor cells (HSPCs) to MI, however, is unclear. Here, we identify a CCR2(+)CD150(+)CD48(-) LSK hematopoietic subset as the most upstream contributor to emergency myelopoiesis after ischemic organ injury. This subset has 4-fold higher proliferation rates than CCR2(-)CD150(+)CD48(-) LSK cells, displays a myeloid differentiation bias, and dominates the migratory HSPC population. We further demonstrate that the myeloid translocation gene 16 (Mtg16) regulates CCR2(+) HSPC emergence. Mtg16(-/-) mice have decreased levels of systemic monocytes and infarct-associated macrophages and display compromised tissue healing and post-MI heart failure. Together, these data provide insights into regulation of emergency hematopoiesis after ischemic injury and identify potential therapeutic targets to modulate leukocyte output after MI., (Copyright © 2015 Elsevier Inc. All rights reserved.)
- Published
- 2015
- Full Text
- View/download PDF
34. Macrophages retain hematopoietic stem cells in the spleen via VCAM-1.
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Dutta P, Hoyer FF, Grigoryeva LS, Sager HB, Leuschner F, Courties G, Borodovsky A, Novobrantseva T, Ruda VM, Fitzgerald K, Iwamoto Y, Wojtkiewicz G, Sun Y, Da Silva N, Libby P, Anderson DG, Swirski FK, Weissleder R, and Nahrendorf M
- Subjects
- Animals, Apolipoproteins E genetics, Apolipoproteins E immunology, Atherosclerosis genetics, Atherosclerosis immunology, Atherosclerosis pathology, Gene Expression Regulation genetics, Gene Expression Regulation immunology, Hematopoiesis, Extramedullary genetics, Hematopoietic Stem Cells pathology, Macrophages pathology, Mice, Mice, Knockout, Myelopoiesis genetics, Myocardial Infarction genetics, Myocardial Infarction immunology, Myocardial Infarction pathology, Nanoparticles, Plaque, Atherosclerotic genetics, Plaque, Atherosclerotic immunology, Plaque, Atherosclerotic pathology, RNA Interference, Receptor, Macrophage Colony-Stimulating Factor genetics, Receptor, Macrophage Colony-Stimulating Factor immunology, Sialic Acid Binding Ig-like Lectin 1 genetics, Sialic Acid Binding Ig-like Lectin 1 immunology, Spleen pathology, Vascular Cell Adhesion Molecule-1 genetics, Hematopoiesis, Extramedullary immunology, Hematopoietic Stem Cells immunology, Macrophages immunology, Myelopoiesis immunology, Spleen immunology, Vascular Cell Adhesion Molecule-1 immunology
- Abstract
Splenic myelopoiesis provides a steady flow of leukocytes to inflamed tissues, and leukocytosis correlates with cardiovascular mortality. Yet regulation of hematopoietic stem cell (HSC) activity in the spleen is incompletely understood. Here, we show that red pulp vascular cell adhesion molecule 1 (VCAM-1)(+) macrophages are essential to extramedullary myelopoiesis because these macrophages use the adhesion molecule VCAM-1 to retain HSCs in the spleen. Nanoparticle-enabled in vivo RNAi silencing of the receptor for macrophage colony stimulation factor (M-CSFR) blocked splenic macrophage maturation, reduced splenic VCAM-1 expression and compromised splenic HSC retention. Both, depleting macrophages in CD169 iDTR mice or silencing VCAM-1 in macrophages released HSCs from the spleen. When we silenced either VCAM-1 or M-CSFR in mice with myocardial infarction or in ApoE(-/-) mice with atherosclerosis, nanoparticle-enabled in vivo RNAi mitigated blood leukocytosis, limited inflammation in the ischemic heart, and reduced myeloid cell numbers in atherosclerotic plaques., (© 2015 Dutta et al.)
- Published
- 2015
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35. In vivo silencing of the transcription factor IRF5 reprograms the macrophage phenotype and improves infarct healing.
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Courties G, Heidt T, Sebas M, Iwamoto Y, Jeon D, Truelove J, Tricot B, Wojtkiewicz G, Dutta P, Sager HB, Borodovsky A, Novobrantseva T, Klebanov B, Fitzgerald K, Anderson DG, Libby P, Swirski FK, Weissleder R, and Nahrendorf M
- Subjects
- Animals, Disease Models, Animal, Interferon Regulatory Factors metabolism, Mice, Myocardial Infarction metabolism, Myocardial Infarction physiopathology, Myocardium pathology, Phenotype, Gene Expression Regulation, Interferon Regulatory Factors genetics, Macrophages metabolism, Myocardial Infarction genetics, Myocardium metabolism, RNA genetics, Ventricular Remodeling
- Abstract
Objectives: The aim of this study was to test whether silencing of the transcription factor interferon regulatory factor 5 (IRF5) in cardiac macrophages improves infarct healing and attenuates post-myocardial infarction (MI) remodeling., Background: In healing wounds, the M1 toward M2 macrophage phenotype transition supports resolution of inflammation and tissue repair. Persistence of inflammatory M1 macrophages may derail healing and compromise organ functions. The transcription factor IRF5 up-regulates genes associated with M1 macrophages., Methods: Here we used nanoparticle-delivered small interfering ribonucleic acid (siRNA) to silence IRF5 in macrophages residing in MIs and in surgically-induced skin wounds in mice., Results: Infarct macrophages expressed high levels of IRF5 during the early inflammatory wound-healing stages (day 4 after coronary ligation), whereas expression of the transcription factor decreased during the resolution of inflammation (day 8). Following in vitro screening, we identified an siRNA sequence that, when delivered by nanoparticles to wound macrophages, efficiently suppressed expression of IRF5 in vivo. Reduction of IRF5 expression, a factor that regulates macrophage polarization, reduced expression of inflammatory M1 macrophage markers, supported resolution of inflammation, accelerated cutaneous and infarct healing, and attenuated development of post-MI heart failure after coronary ligation as measured by protease targeted fluorescence molecular tomography-computed tomography imaging and cardiac magnetic resonance imaging (p < 0.05)., Conclusions: This work identified a new therapeutic avenue to augment resolution of inflammation in healing infarcts by macrophage phenotype manipulation. This therapeutic concept may be used to attenuate post-MI remodeling and heart failure., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
- Full Text
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36. Measuring myeloperoxidase activity in biological samples.
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Pulli B, Ali M, Forghani R, Schob S, Hsieh KL, Wojtkiewicz G, Linnoila JJ, and Chen JW
- Subjects
- Animals, Enzyme Activation, Enzyme Assays standards, Extracellular Space metabolism, Female, Intracellular Space metabolism, Leukocyte Count, Male, Mice, Mice, Knockout, Molecular Imaging, Neutrophils enzymology, Peroxidase genetics, Reproducibility of Results, Sensitivity and Specificity, Enzyme Assays methods, Peroxidase metabolism
- Abstract
Background: Enzymatic activity measurements of the highly oxidative enzyme myeloperoxidase (MPO), which is implicated in many diseases, are widely used in the literature, but often suffer from nonspecificity and lack of uniformity. Thus, validation and standardization are needed to establish a robust method that is highly specific, sensitive, and reproducible for assaying MPO activity in biological samples., Principal Findings: We found conflicting results between in vivo molecular MR imaging of MPO, which measures extracellular activity, and commonly used in vitro MPO activity assays. Thus, we established and validated a protocol to obtain extra- and intracellular MPO from murine organs. To validate the MPO activity assays, three different classes of MPO activity assays were used in spike and recovery experiments. However, these assay methods yielded inconsistent results, likely because of interfering substances and other peroxidases present in tissue extracts. To circumvent this, we first captured MPO with an antibody. The MPO activity of the resultant samples was assessed by ADHP and validated against samples from MPO-knockout mice in murine disease models of multiple sclerosis, steatohepatitis, and myocardial infarction. We found the measurements performed using this protocol to be highly specific and reproducible, and when performed using ADHP, to be highly sensitive over a broad range. In addition, we found that intracellular MPO activity correlated well with tissue neutrophil content, and can be used as a marker to assess neutrophil infiltration in the tissue., Conclusion: We validated a highly specific and sensitive assay protocol that should be used as the standard method for all MPO activity assays in biological samples. We also established a method to obtain extra- and intracellular MPO from murine organs. Extracellular MPO activity gives an estimate of the oxidative stress in inflammatory diseases, while intracellular MPO activity correlates well with tissue neutrophil content. A detailed step-by-step protocol is provided.
- Published
- 2013
- Full Text
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37. Monocyte-directed RNAi targeting CCR2 improves infarct healing in atherosclerosis-prone mice.
- Author
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Majmudar MD, Keliher EJ, Heidt T, Leuschner F, Truelove J, Sena BF, Gorbatov R, Iwamoto Y, Dutta P, Wojtkiewicz G, Courties G, Sebas M, Borodovsky A, Fitzgerald K, Nolte MW, Dickneite G, Chen JW, Anderson DG, Swirski FK, Weissleder R, and Nahrendorf M
- Subjects
- Amino Acid Sequence, Animals, Atherosclerosis genetics, Atherosclerosis pathology, Female, Genetic Predisposition to Disease, Genetic Therapy methods, Mice, Mice, Inbred C57BL, Mice, Knockout, Molecular Sequence Data, Monocytes pathology, Myocardial Infarction pathology, Random Allocation, Receptors, CCR2 antagonists & inhibitors, Receptors, CCR2 metabolism, Atherosclerosis therapy, Gene Targeting methods, Monocytes metabolism, Myocardial Infarction genetics, Myocardial Infarction therapy, RNA Interference physiology, Receptors, CCR2 genetics, Wound Healing genetics
- Abstract
Background: Exaggerated and prolonged inflammation after myocardial infarction (MI) accelerates left ventricular remodeling. Inflammatory pathways may present a therapeutic target to prevent post-MI heart failure. However, the appropriate magnitude and timing of interventions are largely unknown, in part because noninvasive monitoring tools are lacking. Here, we used nanoparticle-facilitated silencing of CCR2, the chemokine receptor that governs inflammatory Ly-6C(high) monocyte subset traffic, to reduce infarct inflammation in apolipoprotein E-deficient (apoE(-/-)) mice after MI. We used dual-target positron emission tomography/magnetic resonance imaging of transglutaminase factor XIII (FXIII) and myeloperoxidase (MPO) activity to monitor how monocyte subset-targeted RNAi altered infarct inflammation and healing., Methods and Results: Flow cytometry, gene expression analysis, and histology revealed reduced monocyte numbers and enhanced resolution of inflammation in infarcted hearts of apoE(-/-) mice that were treated with nanoparticle-encapsulated siRNA. To follow extracellular matrix cross-linking noninvasively, we developed a fluorine-18-labeled positron emission tomography agent ((18)F-FXIII). Recruitment of MPO-rich inflammatory leukocytes was imaged with a molecular magnetic resonance imaging sensor of MPO activity (MPO-Gd). Positron emission tomography/magnetic resonance imaging detected anti-inflammatory effects of intravenous nanoparticle-facilitated siRNA therapy (75% decrease of MPO-Gd signal; P<0.05), whereas (18)F-FXIII positron emission tomography reflected unimpeded matrix cross-linking in the infarct. Silencing of CCR2 during the first week after MI improved ejection fraction on day 21 after MI from 29% to 35% (P<0.05)., Conclusion: CCR2-targeted RNAi reduced recruitment of Ly-6C(high) monocytes, attenuated infarct inflammation, and curbed post-MI left ventricular remodeling.
- Published
- 2013
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38. Angiotensin II drives the production of tumor-promoting macrophages.
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Cortez-Retamozo V, Etzrodt M, Newton A, Ryan R, Pucci F, Sio SW, Kuswanto W, Rauch PJ, Chudnovskiy A, Iwamoto Y, Kohler R, Marinelli B, Gorbatov R, Wojtkiewicz G, Panizzi P, Mino-Kenudson M, Forghani R, Figueiredo JL, Chen JW, Xavier R, Swirski FK, Nahrendorf M, Weissleder R, and Pittet MJ
- Subjects
- Adenocarcinoma genetics, Adenocarcinoma pathology, Adenocarcinoma of Lung, Angiotensin II metabolism, Animals, Carcinoma, Non-Small-Cell Lung genetics, Carcinoma, Non-Small-Cell Lung pathology, Cell Communication, Cell Movement, Cell Proliferation, Gene Expression, Hematopoietic Stem Cells metabolism, Hematopoietic Stem Cells pathology, Humans, Lung Neoplasms genetics, Lung Neoplasms pathology, Lysophospholipids metabolism, Macrophages pathology, Mice, Mice, Transgenic, Signal Transduction, Sphingosine analogs & derivatives, Sphingosine metabolism, Spleen pathology, Tumor Burden, Adenocarcinoma metabolism, Angiotensin II genetics, Carcinoma, Non-Small-Cell Lung metabolism, Lung Neoplasms metabolism, Macrophages metabolism, Spleen metabolism
- Abstract
Macrophages frequently infiltrate tumors and can enhance cancer growth, yet the origins of the macrophage response are not well understood. Here we address molecular mechanisms of macrophage production in a conditional mouse model of lung adenocarcinoma. We report that overproduction of the peptide hormone Angiotensin II (AngII) in tumor-bearing mice amplifies self-renewing hematopoietic stem cells (HSCs) and macrophage progenitors. The process occurred in the spleen but not the bone marrow, and was independent of hemodynamic changes. The effects of AngII required direct hormone ligation on HSCs, depended on S1P(1) signaling, and allowed the extramedullary tissue to supply new tumor-associated macrophages throughout cancer progression. Conversely, blocking AngII production prevented cancer-induced HSC and macrophage progenitor amplification and thus restrained the macrophage response at its source. These findings indicate that AngII acts upstream of a potent macrophage amplification program and that tumors can remotely exploit the hormone's pathway to stimulate cancer-promoting immunity., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
- Full Text
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39. Single reporter for targeted multimodal in vivo imaging.
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Niers JM, Chen JW, Lewandrowski G, Kerami M, Garanger E, Wojtkiewicz G, Waterman P, Keliher E, Weissleder R, and Tannous BA
- Subjects
- Animals, Biotin chemistry, Biotin metabolism, Brain Neoplasms diagnosis, Brain Neoplasms metabolism, Humans, Luciferases chemistry, Luciferases metabolism, Luminescent Measurements, Mice, Mice, Nude, Tumor Cells, Cultured, Brain Neoplasms genetics, Genes, Reporter genetics, Single-Cell Analysis methods
- Abstract
We have developed a multifaceted, highly specific reporter for multimodal in vivo imaging and applied it for detection of brain tumors. A metabolically biotinylated, membrane-bound form of Gaussia luciferase was synthesized, termed mbGluc-biotin. We engineered glioma cells to express this reporter and showed that brain tumor formation can be temporally imaged by bioluminescence following systemic administration of coelenterazine. Brain tumors expressing this reporter had high sensitivity for detection by magnetic resonance and fluorescence tomographic imaging upon injection of streptavidin conjugated to magnetic nanoparticles or fluorophore, respectively. Moreover, single photon emission computed tomography showed enhanced imaging of these tumors upon injection with streptavidin complexed to (111)In-DTPA-biotin. This work shows for the first time a single small reporter (∼40 kDa) which can be monitored with most available molecular imaging modalities and can be extended for single cell imaging using intravital microscopy, allowing real-time tracking of any cell expressing it in vivo.
- Published
- 2012
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40. Early window of diabetes determinism in NOD mice, dependent on the complement receptor CRIg, identified by noninvasive imaging.
- Author
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Fu W, Wojtkiewicz G, Weissleder R, Benoist C, and Mathis D
- Subjects
- Animals, Cell Separation, Diabetes Mellitus, Type 1 genetics, Disease Progression, Female, Ferric Compounds, Flow Cytometry, Gene Expression Profiling, Islets of Langerhans pathology, Magnetic Resonance Imaging, Male, Metal Nanoparticles, Mice, Mice, Inbred NOD, Receptors, Complement immunology, Diabetes Mellitus, Type 1 diagnosis, Diabetes Mellitus, Type 1 immunology, Early Diagnosis, Macrophages immunology, Macrophages metabolism, Receptors, Complement metabolism
- Abstract
All juvenile mice of the nonobese diabetic (NOD) strain develop insulitis, but there is considerable variation in their progression to diabetes. Here we used a strategy based on magnetic resonance imaging (MRI) of magnetic nanoparticles to noninvasively visualize local effects of pancreatic-islet inflammation to predict the onset of diabetes in NOD mice. MRI signals acquired during a narrow early time window allowed us to sort mice into groups that would progress to clinical disease or not and to estimate the time to diabetes development. We exploited this approach to identify previously unknown molecular and cellular elements correlated with disease protection, including the complement receptor of the immunoglobulin superfamily (CRIg), which marked a subset of macrophages associated with diabetes resistance. Administration of a fusion of CRIg and the Fc portion of immunoglobulin resulted in lower MRI signals and diabetes incidence. In addition to identifying regulators of disease progression, we show here that diabetes is set at an early age in NOD mice.
- Published
- 2012
- Full Text
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41. In vivo imaging of T cell delivery to tumors after adoptive transfer therapy.
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Pittet MJ, Grimm J, Berger CR, Tamura T, Wojtkiewicz G, Nahrendorf M, Romero P, Swirski FK, and Weissleder R
- Subjects
- Animals, Antigens immunology, Cell Line, Tumor, Cell Movement, Lymphopenia immunology, Lymphopenia pathology, Mice, Mice, Inbred BALB C, Neoplasms therapy, Tomography Scanners, X-Ray Computed, Adoptive Transfer, Immunotherapy, Adoptive, Neoplasms immunology, Neoplasms pathology, T-Lymphocytes cytology, T-Lymphocytes immunology
- Abstract
Adoptive transfer therapy of in vitro-expanded tumor-specific cytolytic T lymphocytes (CTLs) can mediate objective cancer regression in patients. Yet, technical limitations hamper precise monitoring of posttherapy T cell responses. Here we show in a mouse model that fused single photon emission computed tomography and x-ray computed tomography allows quantitative whole-body imaging of (111)In-oxine-labeled CTLs at tumor sites. Assessment of CTL localization is rapid, noninvasive, three-dimensional, and can be repeated for longitudinal analyses. We compared the effects of lymphodepletion before adoptive transfer on CTL recruitment and report that combined treatment increased intratumoral delivery of CTLs and improved antitumor efficacy. Because (111)In-oxine is a Food and Drug Administration-approved clinical agent, and human SPECT-CT systems are available, this approach should be clinically translatable, insofar as it may assess the efficacy of immunization procedures in individual patients and lead to development of more effective therapies.
- Published
- 2007
- Full Text
- View/download PDF
42. An X-ray computed tomography imaging agent based on long-circulating bismuth sulphide nanoparticles.
- Author
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Rabin O, Manuel Perez J, Grimm J, Wojtkiewicz G, and Weissleder R
- Subjects
- Animals, Bismuth adverse effects, Blood Vessels, Contrast Media adverse effects, Dose-Response Relationship, Drug, Drug Stability, Liver, Lymph Nodes, Mice, Nanostructures adverse effects, Nanostructures analysis, Sulfides adverse effects, Bismuth analysis, Bismuth chemistry, Contrast Media analysis, Contrast Media chemistry, Nanostructures chemistry, Sulfides analysis, Sulfides chemistry, Tomography, X-Ray Computed methods
- Abstract
Nanomaterials have become increasingly important in the development of new molecular probes for in vivo imaging, both experimentally and clinically. Nanoparticulate imaging probes have included semiconductor quantum dots, magnetic and magnetofluorescent nanoparticles, gold nanoparticles and nanoshells, among others. However, the use of nanomaterials for one of the most common imaging techniques, computed tomography (CT), has remained unexplored. Current CT contrast agents are based on small iodinated molecules. They are effective in absorbing X-rays, but non-specific distribution and rapid pharmacokinetics have rather limited their microvascular and targeting performance. Here we propose the use of a polymer-coated Bi(2)S(3) nanoparticle preparation as an injectable CT imaging agent. This preparation demonstrates excellent stability at high concentrations (0.25 M Bi(3+)), high X-ray absorption (fivefold better than iodine), very long circulation times (>2 h) in vivo and an efficacy/safety profile comparable to or better than iodinated imaging agents. We show the utility of these polymer-coated Bi(2)S(3) nanoparticles for enhanced in vivo imaging of the vasculature, the liver and lymph nodes in mice. These nanoparticles and their bioconjugates are expected to become an important adjunct to in vivo imaging of molecular targets and pathological conditions.
- Published
- 2006
- Full Text
- View/download PDF
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