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Background: Anthracycline-induced cardiomyopathy (AIC) may be irreversible with a poor prognosis, disproportionately affecting women and young adults. Administration of allogeneic bone marrow-derived mesenchymal stromal cells (allo-MSCs) is a promising approach to heart failure (HF) treatment., Objectives: SENECA (Stem Cell Injection in Cancer Survivors) was a phase 1 study of allo-MSCs in AIC., Methods: Cancer survivors with chronic AIC (mean age 56.6 years; 68% women; NT-proBNP 1,426 pg/ml; 6 enrolled in an open-label, lead-in phase and 31 subjects randomized 1:1) received 1 × 10 8 allo-MSCs or vehicle transendocardially. Primary objectives were safety and feasibility. Secondary efficacy measures included cardiac function and structure measured by cardiac magnetic resonance imaging (CMR), functional capacity, quality of life (Minnesota Living with Heart Failure Questionnaire), and biomarkers., Results: A total of 97% of subjects underwent successful study product injections; all allo-MSC-assigned subjects received the target dose of cells. Follow-up visits were well-attended (92%) with successful collection of endpoints in 94% at the 1-year visit. Although 58% of subjects had non-CMR compatible devices, CMR endpoints were successfully collected in 84% of subjects imaged at 1 year. No new tumors were reported. There were no significant differences between allo-MSC and vehicle groups with regard to clinical outcomes. Secondary measures included 6-min walk test (p = 0.056) and Minnesota Living with Heart Failure Questionnaire score (p = 0.048), which tended to favor the allo-MSC group., Conclusions: In this first-in-human study of cell therapy in patients with AIC, transendocardial administration of allo-MSCs appears safe and feasible, and CMR was successfully performed in the majority of the HF patients with devices. This study lays the groundwork for phase 2 trials aimed at assessing efficacy of cell therapy in patients with AIC.

The University of Kansas School of Medicine (KUSOM) educates physicians to meet the needs of a rural and increasingly diverse state. In 2014, the school's curriculum was not aligned with student needs and faculty desires. Concurrently, the state teamed with philanthropic sources to fund the construction of a new health education building (HEB), resulting in a unique opportunity to simultaneously construct a building and a new curriculum. To support the needs of KUSOM students, the faculty developed the Active, Competency-based, Excellence-driven (ACE) curriculum. ACE focuses on multiple forms of active education including flipped classrooms, case-based collaborative and problem-based learning, and interprofessional and simulation-based activities. The HEB was designed to support ACE with large flat learning studios, small group rooms, and multiple simulation spaces. This unique opportunity to innovate the form and function of KUSOM medical education forever changed the future of medicine in Kansas and provided a paradigm for curricular change., Competing Interests: Potential Conflicts of Interest: None disclosed., (© 2020 The American Clinical and Climatological Association.)

An 8-year small grants program funded by an alumni association has awarded $814,356 to 50 principal investigators for educational research. The 63 projects principally concerned simulation, educational tools and techniques, interprofessional education, and pilot projects for curricular reform. Awardees identify career growth and institutional advancement of education as major outcomes. Four publications, 63 posters/presentations, nationally disseminated educational materials, and external grants have been generated. Other outcomes include a second small grants program and travel funding for educational scholarship. The alumni association has made additional investment of over $1.8 million in educational development and has been nationally recognized for its collaborative philanthropy., Competing Interests: Conflict of InterestThe authors declare that they have no conflict of interest., (© International Association of Medical Science Educators 2019.)

Purpose: Tissue engineered heart valves (TEHV) are being investigated to address the limitations of currently available valve prostheses. In order to advance a wide variety of TEHV approaches, the goal of this study was to develop a cardiac valve bioreactor system capable of conditioning living valves with a range of hydrodynamic conditions as well as capable of assessing hydrodynamic performance to ISO 5840 standards., Methods: A bioreactor system was designed based on the Windkessel approach. Novel features including a purpose-built valve chamber and pressure feedback control were incorporated to maintain asepsis while achieving a range of hydrodynamic conditions. The system was validated by testing hydrodynamic conditions with a bioprosthesis and by operating with cell culture medium for 4 weeks and living cells for 2 weeks., Results: The bioreactor system was able to produce a range of pressure and flow conditions from static to resting adult left ventricular outflow tract to pathological including hypertension. The system operated aseptically for 4 weeks and cell viability was maintained for 2 weeks. The system was also able to record the pressure and flow data needed to calculate effective orifice area and regurgitant fraction., Conclusions: We have developed a single bioreactor system that allows for step-wise conditioning protocols to be developed for each unique TEHV design as well as allows for hydrodynamic performance assessment.

Incomplete endothelialization of intracoronary stents has been associated with stent thrombosis and recurrent symptoms, whereas prolonged use of dual antiplatelet therapy increases bleeding-related adverse events. Facilitated endothelialization has the potential to improve clinical outcomes in patients who are unable to tolerate dual antiplatelet therapy. The objective of this study was to demonstrate the feasibility of magnetic cell capture to rapidly endothelialize intracoronary stents in a large animal model. A novel stent was developed from a magnetizable duplex stainless steel (2205 SS). Polylactic-co-glycolic acid and magnetite (Fe 3 O 4 ) were used to synthesize biodegradable superparamagnetic iron oxide nanoparticles, and these were used to label autologous blood outgrowth endothelial cells. Magnetic 2205 SS and nonmagnetic 316L SS control stents were implanted in the coronary arteries of pigs (n = 11), followed by intracoronary delivery of magnetically labeled cells to 2205 SS stents. In this study, we show extensive endothelialization of magnetic 2205 SS stents (median 98.4% cell coverage) within 3 days, whereas the control 316L SS stents exhibited significantly less coverage (median 48.9% cell coverage, p < 0.0001). This demonstrates the ability of intracoronary delivery of magnetic nanoparticle labeled autologous endothelial cells to improve endothelialization of magnetized coronary stents within 3 days of implantation.

Objectives: SENECA (StEm cell iNjECtion in cAncer survivors) is a phase I, randomized, double-blind, placebo-controlled study to evaluate the safety and feasibility of delivering allogeneic mesenchymal stromal cells (allo-MSCs) transendocardially in subjects with anthracycline-induced cardiomyopathy (AIC)., Background: AIC is an incurable and often fatal syndrome, with a prognosis worse than that of ischemic or nonischemic cardiomyopathy. Recently, cell therapy with MSCs has emerged as a promising new approach to repair damaged myocardium., Methods: The study population is 36 cancer survivors with a diagnosis of AIC, left ventricular (LV) ejection fraction ≤40%, and symptoms of heart failure (NYHA class II-III) on optimally-tolerated medical therapy. Subjects must be clinically free of cancer for at least two years with a ≤ 30% estimated five-year risk of recurrence. The first six subjects participated in an open-label, lead-in phase and received 100 million allo-MSCs; the remaining 30 will be randomized 1:1 to receive allo-MSCs or vehicle via 20 transendocardial injections. Efficacy measures (obtained at baseline, 6 months, and 12 months) include MRI evaluation of LV function, LV volumes, fibrosis, and scar burden; assessment of exercise tolerance (six-minute walk test) and quality of life (Minnesota Living with Heart Failure Questionnaire); clinical outcomes (MACE and cumulative days alive and out of hospital); and biomarkers of heart failure (NT-proBNP)., Conclusions: This is the first clinical trial using direct cardiac injection of cells for the treatment of AIC. If administration of allo-MSCs is found feasible and safe, SENECA will pave the way for larger phase II/III studies with therapeutic efficacy as the primary outcome., (Copyright © 2018. Published by Elsevier Inc.)

Rationale: Autologous bone marrow mesenchymal stem cells (MSCs) and c-kit + cardiac progenitor cells (CPCs) are 2 promising cell types being evaluated for patients with heart failure (HF) secondary to ischemic cardiomyopathy. No information is available in humans about the relative efficacy of MSCs and CPCs and whether their combination is more efficacious than either cell type alone., Objective: CONCERT-HF (Combination of Mesenchymal and c-kit + Cardiac Stem Cells As Regenerative Therapy for Heart Failure) is a phase II trial aimed at elucidating these issues by assessing the feasibility, safety, and efficacy of transendocardial administration of autologous MSCs and CPCs, alone and in combination, in patients with HF caused by chronic ischemic cardiomyopathy (coronary artery disease and old myocardial infarction)., Methods and Results: Using a randomized, double-blinded, placebo-controlled, multicenter, multitreatment, and adaptive design, CONCERT-HF examines whether administration of MSCs alone, CPCs alone, or MSCs+CPCs in this population alleviates left ventricular remodeling and dysfunction, reduces scar size, improves quality of life, or augments functional capacity. The 4-arm design enables comparisons of MSCs alone with CPCs alone and with their combination. CONCERT-HF consists of 162 patients, 18 in a safety lead-in phase (stage 1) and 144 in the main trial (stage 2). Stage 1 is complete, and stage 2 is currently randomizing patients from 7 centers across the United States., Conclusions: CONCERT-HF will provide important insights into the potential therapeutic utility of MSCs and CPCs, given alone and in combination, for patients with HF secondary to ischemic cardiomyopathy., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02501811., (© 2018 American Heart Association, Inc.)

Rationale: The TIME trial (Timing in Myocardial Infarction Evaluation) was the first cell therapy trial sufficiently powered to determine if timing of cell delivery after ST-segment-elevation myocardial infarction affects recovery of left ventricular (LV) function., Objective: To report the 2-year clinical and cardiac magnetic resonance imaging results and their modification by microvascular obstruction., Methods and Results: TIME was a randomized, double-blind, placebo-controlled trial comparing 150 million bone marrow mononuclear cells versus placebo in 120 patients with anterior ST-segment-elevation myocardial infarctions resulting in LV dysfunction. Primary end points included changes in global (LV ejection fraction) and regional (infarct and border zone) function. Secondary end points included changes in LV volumes, infarct size, and major adverse cardiac events. Here, we analyzed the continued trajectory of these measures out to 2 years and the influence of microvascular obstruction present at baseline on these long-term outcomes. At 2 years (n=85), LV ejection fraction was similar in the bone marrow mononuclear cells (48.7%) and placebo groups (51.6%) with no difference in regional LV function. Infarct size and LV mass decreased ≥30% in each group at 6 months and declined gradually to 2 years. LV volumes increased ≈10% at 6 months and remained stable to 2 years. Microvascular obstruction was present in 48 patients at baseline and was associated with significantly larger infarct size (56.5 versus 36.2 g), greater adverse LV remodeling, and marked reduction in LV ejection fraction recovery (0.2% versus 6.2%)., Conclusions: In one of the longest serial cardiac magnetic resonance imaging analyses of patients with large anterior ST-segment-elevation myocardial infarctions, bone marrow mononuclear cells administration did not improve recovery of LV function over 2 years. Microvascular obstruction was associated with reduced recovery of LV function, greater adverse LV remodeling, and more device implantations. The use of cardiac magnetic resonance imaging leads to greater dropout of patients over time because of device implantation in patients with more severe LV dysfunction resulting in overestimation of clinical stability of the cohort., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00684021., (© 2017 American Heart Association, Inc.)

Background: Atherosclerotic peripheral artery disease affects 8% to 12% of Americans >65 years of age and is associated with a major decline in functional status, increased myocardial infarction and stroke rates, and increased risk of ischemic amputation. Current treatment strategies for claudication have limitations. PACE (Patients With Intermittent Claudication Injected With ALDH Bright Cells) is a National Heart, Lung, and Blood Institute-sponsored, randomized, double-blind, placebo-controlled, phase 2 exploratory clinical trial designed to assess the safety and efficacy of autologous bone marrow-derived aldehyde dehydrogenase bright (ALDHbr) cells in patients with peripheral artery disease and to explore associated claudication physiological mechanisms., Methods: All participants, randomized 1:1 to receive ALDHbr cells or placebo, underwent bone marrow aspiration and isolation of ALDHbr cells, followed by 10 injections into the thigh and calf of the index leg. The coprimary end points were change from baseline to 6 months in peak walking time (PWT), collateral count, peak hyperemic popliteal flow, and capillary perfusion measured by magnetic resonance imaging, as well as safety., Results: A total of 82 patients with claudication and infrainguinal peripheral artery disease were randomized at 9 sites, of whom 78 had analyzable data (57 male, 21 female patients; mean age, 66±9 years). The mean±SEM differences in the change over 6 months between study groups for PWT (0.9±0.8 minutes; 95% confidence interval [CI] -0.6 to 2.5; P =0.238), collateral count (0.9±0.6 arteries; 95% CI, -0.2 to 2.1; P=0.116), peak hyperemic popliteal flow (0.0±0.4 mL/s; 95% CI, -0.8 to 0.8; P =0.978), and capillary perfusion (-0.2±0.6%; 95% CI, -1.3 to 0.9; P=0.752) were not significant. In addition, there were no significant differences for the secondary end points, including quality-of-life measures. There were no adverse safety outcomes. Correlative relationships between magnetic resonance imaging measures and PWT were not significant. A post hoc exploratory analysis suggested that ALDHbr cell administration might be associated with an increase in the number of collateral arteries (1.5±0.7; 95% CI, 0.1-2.9; P =0.047) in participants with completely occluded femoral arteries., Conclusions: ALDHbr cell administration did not improve PWT or magnetic resonance outcomes, and the changes in PWT were not associated with the anatomic or physiological magnetic resonance imaging end points. Future peripheral artery disease cell therapy investigational trial design may be informed by new anatomic and perfusion insights., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01774097., (© 2017 American Heart Association, Inc.)

Background: Although several preclinical studies have shown that bone marrow cell (BMC) transplantation promotes cardiac recovery after myocardial infarction, clinical trials with unfractionated bone marrow have shown variable improvements in cardiac function., Methods: To determine whether in a population of post-myocardial infarction patients, functional recovery after BM transplant is associated with specific BMC subpopulation, we examined the association between BMCs with left ventricular (LV) function in the LateTIME-CCTRN trial., Results: In this population, we found that older individuals had higher numbers of BM CD133(+) and CD3(+) cells. Bone marrow from individuals with high body mass index had lower CD45(dim)/CD11b(dim) levels, whereas those with hypertension and higher C-reactive protein levels had higher numbers of CD133(+) cells. Smoking was associated with higher levels of CD133(+)/CD34(+)/VEGFR2(+) cells and lower levels of CD3(+) cells. Adjusted multivariate analysis indicated that CD11b(dim) cells were negatively associated with changes in LV ejection fraction and wall motion in both the infarct and border zones. Change in LV ejection fraction was positively associated with CD133(+), CD34(+), and CD45(+)/CXCR4(dim) cells as well as faster BMC growth rates in endothelial colony forming assays., Conclusions: In the LateTIME population, BM composition varied with patient characteristics and treatment. Irrespective of cell therapy, recovery of LV function was greater in patients with greater BM abundance of CD133(+) and CD34(+) cells and worse in those with higher levels of CD11b(dim) cells. Bone marrow phenotype might predict clinical response before BMC therapy and administration of selected BM constituents could potentially improve outcomes of other future clinical trials., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Decellularized heart valves are emerging as a potential alternative to current bioprostheses for valve replacement. Whereas techniques of decellularization have been thoroughly examined, terminal sterilization techniques have not received the same scrutiny., Methods: This study evaluated low-dose gamma irradiation as a sterilization method for decellularized heart valves. Incubation of valves and transmission electron microscopy evaluation after different doses of gamma irradiation were used to determine the optimal dose of gamma irradiation. Quantitative evaluation of mechanical properties was done by tensile mechanical testing of isolated cusps. Sterilized decellularized heart valves were tested in a sheep model (n = 3 [1 at 1,500 Gy and 2 at 3,000 Gy]) of pulmonary valve replacement., Results: Valves sterilized with gamma radiation between 1,000 Gy and 3,000 Gy were found to be optimal with in vitro testing. However, in vivo testing showed deteriorating valve function within 2 months. On explant, the valve with 1,500 Gy gamma irradiation showed signs of endocarditis with neutrophils on hematoxylin and eosin staining, and positive gram stain resembling streptococcus infection. The 3,000 Gy valves had no evidence of infection, but the hematoxylin and eosin staining showed evidence of wound remodeling with macrophages and fibroblasts. Tensile strength testing showed decreased strength (0 Gy: 2.53 ± 0.98 MPa, 1,500 Gy: 2.03 ± 1.23 MPa, and 3,000 Gy: 1.26 ± 0.90 MPa) with increasing levels of irradiation., Conclusions: Low-dose gamma irradiation does not maintain the mechanical integrity of valves, and the balance between sterilization and damage may not be able to be achieved with gamma irradiation. Other methods of terminal sterilization must be pursued and evaluated., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The vasculature plays an indispensible role in organ development and maintenance of tissue homeostasis, such that disturbances to it impact greatly on developmental and postnatal health. Although cell turnover in healthy blood vessels is low, it increases considerably under pathological conditions. The principle sources for this phenomenon have long been considered to be the recruitment of cells from the peripheral circulation and the re-entry of mature cells in the vessel wall back into cell cycle. However, recent discoveries have also uncovered the presence of a range of multipotent and lineage-restricted progenitor cells in the mural layers of postnatal blood vessels, possessing high proliferative capacity and potential to generate endothelial, smooth muscle, hematopoietic or mesenchymal cell progeny. In particular, the tunica adventitia has emerged as a progenitor-rich compartment with niche-like characteristics that support and regulate vascular wall progenitor cells. Preliminary data indicate the involvement of some of these vascular wall progenitor cells in vascular disease states, adding weight to the notion that the adventitia is integral to vascular wall pathogenesis, and raising potential implications for clinical therapies. This review discusses the current body of evidence for the existence of vascular wall progenitor cell subpopulations from development to adulthood and addresses the gains made and significant challenges that lie ahead in trying to accurately delineate their identities, origins, regulatory pathways, and relevance to normal vascular structure and function, as well as disease., (© 2015 American Heart Association, Inc.)

Unlabelled: Chronic passive hepatic congestion (congestive hepatopathy) leads to hepatic fibrosis; however, the mechanisms involved in this process are not well understood. We developed a murine experimental model of congestive hepatopathy through partial ligation of the inferior vena cava (pIVCL). C57BL/6 and transgenic mice overexpressing tissue factor pathway inhibitor (SM22α-TFPI) were subjected to pIVCL or sham. Liver and blood samples were collected and analyzed in immunohistochemical, morphometric, real-time polymerase chain reaction, and western blot assays. Hepatic fibrosis and portal pressure were significantly increased after pIVCL concurrent with hepatic stellate cell (HSC) activation. Liver stiffness, as assessed by magnetic resonance elastography, correlated with portal pressure and preceded fibrosis in our model. Hepatic sinusoidal thrombosis as evidenced by fibrin deposition was demonstrated both in mice after pIVCL as well as in humans with congestive hepatopathy. Warfarin treatment and TFPI overexpression both had a protective effect on fibrosis development and HSC activation after pIVCL. In vitro studies show that congestion stimulates HSC fibronectin (FN) fibril assembly through direct effects of thrombi as well as by virtue of mechanical strain. Pretreatment with either Mab13 or Cytochalasin-D, to inhibit β-integrin or actin polymerization, respectively, significantly reduced fibrin and stretch-induced FN fibril assembly., Conclusion: Chronic hepatic congestion leads to sinusoidal thrombosis and strain, which in turn promote hepatic fibrosis. These studies mechanistically link congestive hepatopathy to hepatic fibrosis., (© 2014 by the American Association for the Study of Liver Diseases.)

Rationale: Despite significant interest in bone marrow mononuclear cell (BMC) therapy for ischemic heart disease, current techniques have resulted in only modest benefits. However, selected patients have shown improvements after autologous BMC therapy, but the contributing factors are unclear., Objective: The purpose of this study was to identify BMC characteristics associated with a reduction in infarct size after ST-segment-elevation-myocardial infarction., Methods and Results: This prospective study comprised patients consecutively enrolled in the CCTRN TIME (Cardiovascular Cell Therapy Research Network Timing in Myocardial Infarction Evaluation) trial who agreed to have their BMCs stored and analyzed at the CCTRN Biorepository. Change in infarct size between baseline (3 days after percutaneous coronary intervention) and 6-month follow-up was measured by cardiac MRI. Infarct-size measurements and BMC phenotype and function data were obtained for 101 patients (mean age, 56.5 years; mean screening ejection fraction, 37%; mean baseline cardiac MRI ejection fraction, 45%). At 6 months, 75 patients (74.3%) showed a reduction in infarct size (mean change, -21.0±17.6%). Multiple regression analysis indicated that infarct size reduction was greater in patients who had a larger percentage of CD31(+) BMCs (P=0.046) and in those with faster BMC growth rates in colony-forming unit Hill and endothelial-colony forming cell functional assays (P=0.033 and P=0.032, respectively)., Conclusions: This study identified BMC characteristics associated with a better clinical outcome in patients with segment-elevation-myocardial infarction and highlighted the importance of endothelial precursor activity in regenerating infarcted myocardium. Furthermore, it suggests that for these patients with segment-elevation-myocardial infarction, myocardial repair was more dependent on baseline BMC characteristics than on whether the patient underwent intracoronary BMC transplantation., Clinical Trial Registration Information Url: http://www.clinicaltrials.gov. Unique identifier: NCT00684021., (© 2014 American Heart Association, Inc.)

Over the last 50 years medicine and technology have progressed to the point where it has become commonplace to safely replace damaged or diseased heart valves with mechanical and biological prostheses. Despite the advancements in technology current valve substitutes continue to have significant limitations with regards to thrombogenicity, durability, and inability to grow or remodel. In an attempt to overcome the limitations of currently available valve prosthesis, heart valve tissue engineering has emerged as a promising technique to produce biological valve substitutes. Currently, the field of tissue engineering is focused on delivering complex matrices which include scaffolds and cells separately or together to the damaged site. Additional functional enhancement of the matrices by exposing encoded biological signals to their residing cells in a controlled manner has the potential to augment the tissue engineering approach. This review provides an overview of the delivery of biological reagents to guide and regulate heart valve tissue engineering., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Aims: The objective of the present analysis was to systematically examine the effect of intracoronary bone marrow cell (BMC) therapy on left ventricular (LV) function after ST-segment elevation myocardial infarction in various subgroups of patients by performing a collaborative meta-analysis of randomized controlled trials., Methods and Results: We identified all randomized controlled trials comparing intracoronary BMC infusion as treatment for ST-segment elevation myocardial infarction. We contacted the principal investigator for each participating trial to provide summary data with regard to different pre-specified subgroups [age, diabetes mellitus, time from symptoms to percutaneous coronary intervention, infarct-related artery, LV end-diastolic volume index (EDVI), LV ejection fraction (EF), infarct size, presence of microvascular obstruction, timing of cell infusion, and injected cell number] and three different endpoints [change in LVEF, LVEDVI, and LV end-systolic volume index (ESVI)]. Data from 16 studies were combined including 1641 patients (984 cell therapy, 657 controls). The absolute improvement in LVEF was greater among BMC-treated patients compared with controls: [2.55% increase, 95% confidence interval (CI) 1.83-3.26, P < 0.001]. Cell therapy significantly reduced LVEDVI and LVESVI (-3.17 mL/m², 95% CI: -4.86 to -1.47, P < 0.001; -2.60 mL/m², 95% CI -3.84 to -1.35, P < 0.001, respectively). Treatment benefit in terms of LVEF improvement was more pronounced in younger patients (age <55, 3.38%, 95% CI: 2.36-4.39) compared with older patients (age ≥ 55 years, 1.77%, 95% CI: 0.80-2.74, P = 0.03). This heterogeneity in treatment effect was also observed with respect to the reduction in LVEDVI and LVESVI. Moreover, patients with baseline LVEF <40% derived more benefit from intracoronary BMC therapy. LVEF improvement was 5.30%, 95% CI: 4.27-6.33 in patients with LVEF <40% compared with 1.45%, 95% CI: 0.60 to 2.31 in LVEF ≥ 40%, P < 0.001. No clear interaction was observed between other subgroups and outcomes., Conclusion: Intracoronary BMC infusion is associated with improvement of LV function and remodelling in patients after ST-segment elevation myocardial infarction. Younger patients and patients with a more severely depressed LVEF at baseline derived most benefit from this adjunctive therapy.

Context: While the delivery of cell therapy after ST-segment elevation myocardial infarction (STEMI) has been evaluated in previous clinical trials, the influence of the timing of cell delivery on the effect on left ventricular function has not been analyzed., Objectives: To determine the effect of intracoronary autologous bone marrow mononuclear cell (BMC) delivery after STEMI on recovery of global and regional left ventricular function and whether timing of BMC delivery (3 days vs 7 days after reperfusion) influences this effect., Design, Setting, and Patients: A randomized, 2 × 2 factorial, double-blind, placebo-controlled trial, Timing In Myocardial infarction Evaluation (TIME) enrolled 120 patients with left ventricular dysfunction (left ventricular ejection fraction [LVEF] ≤ 45%) after successful primary percutaneous coronary intervention (PCI) of anterior STEMI between July 17, 2008, and November 15, 2011, as part of the Cardiovascular Cell Therapy Research Network sponsored by the National Heart, Lung, and Blood Institute., Interventions: Intracoronary infusion of 150 × 106 BMCs or placebo (randomized 2:1) within 12 hours of aspiration and cell processing administered at day 3 or day 7 (randomized 1:1) after treatment with PCI., Main Outcome Measures: The primary end points were change in global (LVEF) and regional (wall motion) left ventricular function in infarct and border zones at 6 months measured by cardiac magnetic resonance imaging and change in left ventricular function as affected by timing of treatment on day 3 vs day 7. The secondary end points included major adverse cardiovascular events as well as changes in left ventricular volumes and infarct size., Results: The mean (SD) patient age was 56.9 (10.9) years and 87.5% of participants were male. At 6 months, there was no significant increase in LVEF for the BMC group (45.2% [95% CI, 42.8% to 47.6%] to 48.3% [95% CI, 45.3% to 51.3%) vs the placebo group (44.5% [95% CI, 41.0% to 48.0%] to 47.8% [95% CI, 43.4% to 52.2%]) (P = .96). There was no significant treatment effect on regional left ventricular function observed in either infarct or border zones. There were no significant differences in change in global left ventricular function for patients treated at day 3 (−0.9% [95% CI, −6.6% to 4.9%], P = .76) or day 7 (1.1% [95% CI, −4.7% to 6.9%], P = .70). The timing of treatment had no significant effect on regional left ventricular function recovery. Major adverse events were rare among all treatment groups., Conclusion: Among patients with STEMI treated with primary PCI, the administration of intracoronary BMCs at either 3 days or 7 days after the event had no significant effect on recovery of global or regional left ventricular function compared with placebo., Trial Registration: clinicaltrials.gov Identifier: NCT00684021.

Aims: For the characterization of endothelial progenitor cells (EPCs), commonly the markers CD34 and KDR have been used. CD133+/CD34-/KDR+ cells may represent more immature 'early' progenitors. In patients with coronary artery disease (CAD), a large fraction of EPCs carry the osteoblastic marker osteocalcin (OCN), which may mediate vascular calcification and abnormal repair. The aim of this study was to evaluate the expression of OCN+ 'early' EPCs in patients with risk factors (RFs) and a history of stable (history of stenting/coronary artery bypass grafting) or unstable CAD (myocardial infarction)., Methods and Results: Medical history and blood samples from 282 patients (age 58 ± 16 years) with CAD or at least one RF (mean 2.5 ± 1.5) were analysed. For the analysis of EPC markers (CD133, CD34, KDR) and OCN, the flow cytometry of peripheral blood mononuclear cells was performed. Circulating OCN+/CD133+/CD34-/KDR+ cells (median counts [interquartile range] per 100 000 events) were 15 [4-41] in patients with RF (n = 199), 26 [1-136] in those with a history of stable (n = 57), and 246 [105-308] in those with a history of unstable CAD (n = 26; P < 0.001). The association with unstable CAD remained highly significant even after multivariate adjusting for RFs and the different characteristics of the groups. Osteocalcin positive 'early' EPCs trend to predict further events [HR for each doubling of the cell number: 1.20 (95% CI: 1.00-1.46), P = 0.06]., Conclusion: Circulating OCN+ 'early' EPCs are strongly associated with unstable CAD. Therefore, this particular subset of EPCs could mediate abnormal vascular repair and may help identifying patients with a more unstable phenotype of atherosclerosis.

Context: Vascular calcification, an important feature of diabetic vasculopathy, is an active process potentially mediated by endothelial progenitor cells (EPCs) coexpressing the osteoblastic marker osteocalcin (OCN)., Objective: In this study we tested the hypothesis that cells expressing these markers are associated with the presence of elevated glycated hemoglobin (HbA1c)., Design, Setting, and Patients: This was a cross-sectional comparison. Patients (n = 133, aged 57.4 ± 15.7 yr) were divided into two groups according to the presence of an HbA1c in a (pre-)diabetic (>5.6) or normal range at the time of blood sampling., Methods: Using flow cytometry of peripheral blood mononuclear cells (MNCs), cells positive for OCN, the EPC markers (CD34/KDR and CD133(+)/CD34(-)/KDR(+)) and OCN(+) EPCs were counted., Results: Patients with elevated HbA1c compared with those with normal HbA1c had a significantly higher percentage of circulating OCN(+) MNCs [4.6 (interquartile range 2.68-7.81%) vs. 3.12 (0.99-7.81%), P = 0.035], higher numbers of OCN(+)/CD133(+)/CD34(-)/KDR(+) cells [20 (9-74) vs. 8 (0-19) counts per 100,000 gated events, P < 0.001] and a higher fraction of CD133(+)/CD34(-)/KDR(+) and CD34/KDR cells coexpressing OCN (23.7 ± 24.3 vs. 40.5 ± 34.6%, P = 0.002 and 37.1 ± 39.5 vs. 59.7 ± 37.7%, P = 0.002, respectively). The association between circulating OCN(+)/CD133(+)/CD34(-)/KDR(+) cells and an HbA1c in the (pre-) diabetic range remained strong, even after adjusting for differences in obesity and cardiovascular risk factors, disease, and medications in a multivariate model [odds ratio 1.72 (1.21-2.61), P =0.002]., Conclusion: This study demonstrated that patients with HbA1c in the (pre-)diabetic range have a significant increase in OCN(+) MNCs, and OCN(+)/CD133(+)/CD34(-)/KDR(+) cells, in particular. Whether these cells increase vascular calcification in (pre-)diabetes warrants further studies.

Context: Previous studies using autologous bone marrow mononuclear cells (BMCs) in patients with ischemic cardiomyopathy have demonstrated safety and suggested efficacy., Objective: To determine if administration of BMCs through transendocardial injections improves myocardial perfusion, reduces left ventricular end-systolic volume (LVESV), or enhances maximal oxygen consumption in patients with coronary artery disease or LV dysfunction, and limiting heart failure or angina., Design, Setting, and Patients: A phase 2 randomized double-blind, placebo-controlled trial of symptomatic patients (New York Heart Association classification II-III or Canadian Cardiovascular Society classification II-IV) with a left ventricular ejection fraction of 45% or less, a perfusion defect by single-photon emission tomography (SPECT), and coronary artery disease not amenable to revascularization who were receiving maximal medical therapy at 5 National Heart, Lung, and Blood Institute-sponsored Cardiovascular Cell Therapy Research Network (CCTRN) sites between April 29, 2009, and April 18, 2011., Intervention: Bone marrow aspiration (isolation of BMCs using a standardized automated system performed locally) and transendocardial injection of 100 million BMCs or placebo (ratio of 2 for BMC group to 1 for placebo group)., Main Outcome Measures: Co-primary end points assessed at 6 months: changes in LVESV assessed by echocardiography, maximal oxygen consumption, and reversibility on SPECT. Phenotypic and functional analyses of the cell product were performed by the CCTRN biorepository core laboratory., Results: Of 153 patients who provided consent, a total of 92 (82 men; average age: 63 years) were randomized (n = 61 in BMC group and n = 31 in placebo group). Changes in LVESV index (-0.9 mL/m(2) [95% CI, -6.1 to 4.3]; P = .73), maximal oxygen consumption (1.0 [95% CI, -0.42 to 2.34]; P = .17), and reversible defect (-1.2 [95% CI, -12.50 to 10.12]; P = .84) were not statistically significant. There were no differences found in any of the secondary outcomes, including percent myocardial defect, total defect size, fixed defect size, regional wall motion, and clinical improvement., Conclusion: Among patients with chronic ischemic heart failure, transendocardial injection of autologous BMCs compared with placebo did not improve LVESV, maximal oxygen consumption, or reversibility on SPECT., Trial Registration: clinicaltrials.gov Identifier: NCT00824005.

Tissue factor pathway inhibitor (TFPI) is a potent regulator of tissue factor - factor VII-dependent activation of the tissue factor pathway. TFPI is a serine protease inhibitor that contains three Kunitz domains and a basic carboxyl terminus. TFPI is primarily expressed on endothelial cells, and murine models have demonstrated that its expression regulates vascular thrombosis. The localization of TFPI expression and the requirement for TFPI in development suggest a potential role in regulating vascular structure. Data from animal studies suggest that vascular expression of TFPI inhibits pathologic vascular remodeling and inhibits angiogenesis. The mechanism for these effects is diverse and includes tissue factor and factor Xa-dependent and -independent mechanisms.

Despite preclinical promise, the progress of cell-based therapy to clinical cardiovascular practice has been slowed by several challenges and uncertainties that have been highlighted by the conflicting results of human trials. Most telling has been the revelation that current strategies fall short of achieving sufficient retention and engraftment of cells to meet the ambitious objective of myocardial regeneration. This has sparked novel research into the refinement of cell biology and delivery to overcome these shortcomings. Within this context, molecular imaging has emerged as a valuable tool for providing noninvasive surveillance of cell fate in vivo. Direct and indirect labelling of cells can be coupled with clinically relevant imaging modalities, such as radionuclide single photon emission computed tomography and positron emission tomography, and magnetic resonance imaging, to assess their short- and long-term distributions, along with their viability, proliferation and functional interaction with the host myocardium. This review details the strengths and limitations of the different cell labelling and imaging techniques and their potential application to the clinical realm. We also consider the broader, multifaceted utility of imaging throughout the cell therapy process, providing a discussion of its considerable value during cell delivery and its importance during the evaluation of cardiac outcomes in clinical studies.

Context: Clinical trial results suggest that intracoronary delivery of autologous bone marrow mononuclear cells (BMCs) may improve left ventricular (LV) function when administered within the first week following myocardial infarction (MI). However, because a substantial number of patients may not present for early cell delivery, the efficacy of autologous BMC delivery 2 to 3 weeks post-MI warrants investigation., Objective: To determine if intracoronary delivery of autologous BMCs improves global and regional LV function when delivered 2 to 3 weeks following first MI., Design, Setting, and Patients: A randomized, double-blind, placebo-controlled trial (LateTIME) of the National Heart, Lung, and Blood Institute-sponsored Cardiovascular Cell Therapy Research Network of 87 patients with significant LV dysfunction (LV ejection fraction [LVEF] ≤45%) following successful primary percutaneous coronary intervention (PCI) between July 8, 2008, and February 28, 2011., Interventions: Intracoronary infusion of 150 × 10(6) autologous BMCs (total nucleated cells) or placebo (BMC:placebo, 2:1) was performed within 12 hours of bone marrow aspiration after local automated cell processing., Main Outcome Measures: Changes in global (LVEF) and regional (wall motion) LV function in the infarct and border zone between baseline and 6 months, measured by cardiac magnetic resonance imaging. Secondary end points included changes in LV volumes and infarct size., Results: A total of 87 patients were randomized (mean [SD] age, 57 [11] years; 83% men). Harvesting, processing, and intracoronary delivery of BMCs in this setting was feasible. Change between baseline and 6 months in the BMC group vs placebo for mean LVEF (48.7% to 49.2% vs 45.3% to 48.8%; between-group mean difference, -3.00; 95% CI, -7.05 to 0.95), wall motion in the infarct zone (6.2 to 6.5 mm vs 4.9 to 5.9 mm; between-group mean difference, -0.70; 95% CI, -2.78 to 1.34), and wall motion in the border zone (16.0 to 16.6 mm vs 16.1 to 19.3 mm; between-group mean difference, -2.60; 95% CI, -6.03 to 0.77) were not statistically significant. No significant change in LV volumes and infarct volumes was observed; both groups decreased by a similar amount at 6 months vs baseline., Conclusion: Among patients with MI and LV dysfunction following reperfusion with PCI, intracoronary infusion of autologous BMCs vs intracoronary placebo infusion, 2 to 3 weeks after PCI, did not improve global or regional function at 6 months., Trial Registration: clinicaltrials.gov Identifier: NCT00684060.

Due to the changing population in patients with myocardial infarction, recruiting patients in clinical trials continues to challenge clinical investigators. The Cardiovascular Cell Therapy Research Network (CCTRN) chose to expand the reach and power of its recruitment effort by incorporating both referral and treatment satellite centers. Eight treatment satellites were successfully identified and they screened patients over a two year period. The result of this effort was an increase in recruitment, with these treatment satellites contributing 30% of the patients to two of the three Network studies. The hurdles that these satellite treatment centers faced and how they surmounted them provide instruction to clinical research groups eager to expand to satellite systems and to health care practitioners who are interested in taking part in multicenter clinical trials., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The fundamental contributions that blood vessels make toward organogenesis and tissue homeostasis are reflected by the considerable ramifications that loss of vascular wall integrity has on pre- and postnatal health. During both neovascularization and vessel wall remodeling after insult, the dynamic nature of vascular cell growth and replacement vitiates traditional impressions that blood vessels contain predominantly mature, terminally differentiated cell populations. Recent discoveries have verified the presence of diverse stem/progenitor cells for both vascular and non-vascular progeny within the mural layers of the vasculature. During embryogenesis, this encompasses the emergence of definitive hematopoietic stem cells and multipotent mesoangioblasts from the developing dorsal aorta. Ancestral cells have also been identified and isolated from mature, adult blood vessels, showing variable capacity for endothelial, smooth muscle, and mesenchymal differentiation. At present, the characterization of these different vascular wall progenitors remains somewhat rudimentary, but there is evidence for their constitutive residence within organized compartments in the vessel wall, most compellingly in the tunica adventitia. This review overviews the spectrum of resident stem/progenitor cells that have been documented in macro- and micro-vessels during developmental and adult life and considers the implications for a local, vascular wall stem cell niche(s) in the pathogenesis and treatment of cardiovascular and other diseases.

The emerging sciences of stem cell biology and cellular plasticity have led to the development of cell-based therapies for advanced human disease. Pre-clinical studies which defined the potential of bone marrow-derived mononuclear cells to repair damaged and dysfunctional myocardium led to the rapid advancement of these strategies to the clinic. Such rapid advancement has led to controversy regarding the appropriate conduct of such studies. In the United States, the National Heart, Lung, and Blood Institute established the Cardiovascular Cell Therapy Research Network (CCTRN) to facilitate the early translation of clinical trials of cell therapy for left ventricular dysfunction. The premise upon which the CCTRN was established was that multiple clinical trial sites would interact effectively with a Data Coordinating Center to perform early phase 1 and 2 clinical trials within a highly coordinated network structure. In order to develop this network, the unmet needs of the community needed to be defined, the clinical trials identified, and the structure to perform the studies needed to be established. This manuscript highlights the challenges in the development of the CCTRN and the approaches faced to define a network to perform clinical trials in human cell therapy of cardiovascular disease.

A realistic goal for cardiac cell therapy may be to attenuate left ventricular remodeling following acute myocardial infarction to prevent the development of congestive heart failure. Initial clinical trials of cell therapy have delivered cells 1 to 7 days after acute myocardial infarction. However, many patients at risk of developing congestive heart failure may not be ready for cell delivery at that time-point because of clinical instability or hospitalization at facilities without access to cell therapy. Experience with cell delivery 2 to 3 weeks after acute myocardial infarction has not to date been explored in a clinical trial. The objective of the LateTIME study is to evaluate by cardiac magnetic resonance the effect on global and regional left ventricular function, between baseline and 6 months, of a single intracoronary infusion of 150 × 106 autologous bone marrow mononuclear cells (compared with placebo) when that infusion is administered 2 to 3 weeks after moderate-to-large acute myocardial infarction. The 5 clinical sites of the Cardiovascular Cell Therapy Research Network (CCTRN) will enroll a total of 87 eligible patients in a 2:1 bone marrow mononuclear cells-to-placebo patient ratio; these 87 will have undergone successful percutaneous coronary intervention of a major coronary artery and have left ventricular ejection fractions ≤0.45 by echocardiography. When the results become available, this study should provide insight into the clinical feasibility and appropriate timing of autologous cell therapy in high-risk patients after acute myocardial infarction and percutaneous coronary intervention.

Several previous studies have demonstrated that administration of autologous bone marrow-derived mononuclear cells (BMMNCs) improves cardiac function in patients after acute myocardial infarction (AMI). However, optimum timing of administration has not been investigated in a clinical trial. The Cardiovascular Cell Therapy Research Network was developed and funded by the National Heart, Lung, and Blood Institute to address important questions such as timing of cell delivery and to accelerate research in the use of cell-based therapies. The TIME trial is a randomized, phase II, double-blind, placebo-controlled clinical trial. The 5 member clinical sites of the Cardiovascular Cell Therapy Research Network will enroll 120 eligible patients with moderate-to-large anterior AMIs who have undergone successful percutaneous coronary intervention of the left anterior descending coronary artery and have a left ventricular (LV) ejection fraction

Evidence suggesting that bone marrow and circulating blood may harbor myocardial and vascular progenitor cells was the basis for pre-clinical studies of cell therapy for acute myocardial infarction (MI). Rapid initiation of clinical trials has since followed, with regional myocardial delivery of autologous cells being tested as adjunctive therapies for both acute and chronic left ventricular dysfunction. While clinical cell transplantation trials originally began with the explicit goal of myocardial regeneration, more recently the emphasis has shifted to attempted modulation of myocardial remodeling through other processes, such as mechanical strengthening of scar tissue and promotion of myocardial tissue survival through cellular paracrine effects. This article discusses the scientific rationale for cell therapy strategies in acute MI and provides an overview of the clinical studies that have been undertaken to date.

IGF-I is an important determinant of the vascular response to injury in large part through its ability to stimulate migration and proliferation of smooth muscle cells (SMCs). In this study, we used mice with targeted disruption of the pregnancy-associated plasma protein-A gene (PAPP-A-/-) and wild-type (WT) littermates to test the hypotheses that PAPP-A, a metalloproteinase that cleaves inhibitory IGF binding protein (IGFBP)-4, regulates vascular SMC responses to IGF-I in vitro and is critical for the development of vascular neointima after injury in vivo. Vascular SMCs from PAPP-A-/- mice lacked IGFBP-4 protease activity and failed to respond to treatment with IGF-I in the presence of IGFBP-4, whereas SMCs from WT mice with robust IGFBP-4 protease activity showed significant migratory and proliferative responses to IGF-I/IGFBP-4. For in vivo testing, PAPP-A-/- and WT mice underwent unilateral carotid ligation, a model of injury-induced neointimal hyperplasia. In WT mice, PAPP-A mRNA expression was markedly elevated 7 and 14 d after carotid ligation, associated with a progressive increase in neointimal hyperplasia and, in many cases, with complete occlusion of the vessel at 28 d. In contrast, PAPP-A-/- mice showed little evidence of progression resulting in a 75% reduction in neointimal area when compared with WT at 28 d. Cells staining for proliferating cell nuclear antigen were plentiful in the SMC-rich medial and neointimal areas of the injured WT vessel in stark contrast to the relatively few proliferating cells in the same areas of the PAPP-A-/- vessel. Expression of IGF-I and IGFBP-4 was similarly elevated in injured carotids from WT and PAPP-A-/- mice with no change in IGF-I receptor expression. IGFBP-5, an IGF-responsive gene, was increased 2-fold in WT but not in PAPP-A-/- carotids, suggesting reduced IGF activity in the absence of PAPP-A. Thus, PAPP-A-deficient mice are resistant to neointimal formation after injury, which may be explained in part by the ability of PAPP-A to enhance local IGF-I stimulation of vascular SMCs through proteolysis of IGFBP-4.

Purpose: Gene therapy for chronic retinal diseases will require long-term expression of therapeutic transgenes. Lentiviral and adenoviral (Ad) vectors are gene delivery systems with markedly different properties. Lentiviral vectors require integration into the host genome, which facilitates long-term expression, while Ad vectors remain episomal. We compared time course, location, and extent of transgene expression from replication-deficient feline immunodeficiency virus (FIV) vectors and Ad vectors in neonatal rat retina., Methods: A dose-response study was conducted to determine the optimal subretinal dose for comparison of FIV and Ad vectors with an internal cassette expressing beta-galactosidase under transcriptional control of the CMV immediate-early gene promoter/enhancer. Forty-two five-day old Sprague-Dawley rats received subretinal injections of 2 microl containing 2x10(3) transducing units (TU, n=14), 2x10(4) TU (n=14) or 2x10(5) TU (n=14) of FIV vector (right eye) and Ad vector (left eye). Expression was evaluated 48 h after transduction. In the subsequent long-term expression study, 60 five-day old rats received a subretinal injection of 2x10(5) TU FIV vector (right eye) and Ad vector (left eye). Ten pairs of eyes were analyzed at 1 week, 1 month, 3 months, 6 months, 12 months, and the remainder at 16 months. Eye cups were evaluated in a masked manner for extent of beta-galactosidase expression (graded 0-5) by whole mount microscopy and by cross sectional histology., Results: In the dose-response study, 2x10(5) TU resulted in consistent, widespread retinal transduction with both vectors and was selected as the dose for the subsequent study. In the long-term expression study, FIV vector resulted in a higher grade of expression than Ad at multiple single time points and produced higher overall expression when data from all eyes across the entire 16 month study were analyzed (p=0.01). Retinal expression was present at 16 months with both vectors. beta-galactosidase expression was limited to the retinal pigment epithelium (RPE) until the first month, but later was also found to a lesser extent in neurosensory retina with each vector. In contrast to FIV, most Ad injected eyes showed signs of focal accumulation of macrophage-like cells with disrupted retinal architecture., Conclusions: Both FIV and Ad vectors result in long-term transgene expression in RPE after subretinal injection. FIV vectors show more promise than Ad as delivery systems for retinal diseases since they transduce greater areas of RPE, result in less cellular infiltrate, and cause less disruption of retinal architecture. The persistent expression at 16 months of follow-up suggests that these lentiviral vectors are useful for gene therapy of chronic retinal diseases.

Objective: Vascular gene transfer provides unique opportunities for novel therapies for cardiovascular disease. To define the limitations and expectations of translating preclinical strategies to clinical therapy, the kinetics and extent of vascular transgene expression must be determined., Data Sources: Published clinical and preclinical studies of vascular gene transfer., Data Extraction: Kinetics and extent of vascular transgene expression., Data Synthesis: In spite of ongoing clinical studies in vascular gene transfer, data regarding the kinetics and extent of transgene expression are very limited., Conclusions: For the efficient translation of preclinical to clinical vascular gene transfer studies, the kinetics and extent of transgene expression should be determined. Novel imaging technologies and unique clinical scenarios for obtaining tissue should be considered.

This unit provides a set of protocols for introducing recombinant genes into normal, injured, and atherosclerotic arteries. The protocols include animal preparation, surgical techniques, and delivery systems. Protocols describe gene delivery to normal, injured, and stented porcine iliofemoral arteries, employing a double balloon infusion catheter to deliver the vector. Another basic protocol describes gene delivery to atherosclerotic arteries using a hyperlipidemic double-injury rabbit model, and requires surgical exposure of the artery and instillation of the gene vector via a catheter. Additional protocols describe gene delivery to normal and injured murine carotid and femoral arteries. An Alternate Protocol describes a percutaneous method for arterial gene delivery. These protocols may be adapted to deliver genes to either injured or noninjured atherosclerotic arteries.