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The poor prognosis of pancreatic cancer requires novel treatment options. This review examines the evolution of radiopharmaceuticals in the treatment of pancreatic cancer. Established strategies such as peptide receptor radionuclide therapy (PRRT) offer targeted and effective treatment, compared to conventional treatments. However, there are currently no radiopharmaceuticals approved for the treatment of pancreatic cancer in Europe, which requires further research and novel approaches. New radiopharmaceuticals including radiolabeled antibodies, peptides, and nanotechnological approaches are promising in addressing the challenges of pancreatic cancer therapy. These new agents may offer more specific targeting and potentially improve efficacy compared to traditional therapies. Further research is needed to optimize efficacy, address limitations, and explore the overall potential of these new strategies in the treatment of this aggressive and harmful pathology. [ABSTRACT FROM AUTHOR]

Increased circulating histones correlate with sepsis severity and are a potential therapeutic target. Pre‐clinical studies showed benefit with a histone‐neutralizing polyanion molecule (STC3141). We aimed to investigate the safety, tolerability, and pharmacokinetics of STC3141 in critically ill patients with sepsis. We studied 26 patients with sepsis divided into four cohorts of one, five, ten, and ten subjects, respectively. We conducted a dose‐adjusted, open‐label study to determine the safety, tolerability, and pharmacokinetics of STC3141 administered as an IV infusion for up to 72 h, with rate adjusted to estimated creatinine clearance. Four steady‐state concentrations were targeted. Twenty of the 26 subjects (77%) in the study experienced at least one adverse event (AE). The most frequently reported study drug‐related AE was a mildly prolonged aPTT (four events). Only one AE (pulmonary hemorrhage) led to discontinuation of the drug. After excluding patients receiving renal replacement therapy (RRT) patients, clearance ranged from 3.3 to 4.2 L/h across cohorts and was essentially completely renal in nature. Half‐life values ranged from 5 to 7 h. The mean (±SD) terminal half‐life for non‐RRT subjects and for whom it was possible to calculate was approximately 9 (±4.77) h but increased to 19 (±7.94) h for subjects on RRT. Overall, 18 (69.2%) patients completed the study to day eight in the ICU, and 22 (84.6%) survived to 28 days. STC3141 administration appeared to have an acceptable degree of safety and tolerability and expected pharmacokinetics. Cautious, larger randomized efficacy trials in sepsis appear justified. [ABSTRACT FROM AUTHOR]

Neutrophil extracellular traps (NETs) have been implicated in the pathology of various inflammatory conditions. In cancer, NETs have been demonstrated to induce systemic inflammation, impair peripheral vessel and organ function and promote metastasis. Here we show that the plasma level of NETs is significantly higher in patients with metastatic breast cancer compared to those with local disease, or those that were considered cured at a 5‐year follow‐up, confirming NETs as interesting therapeutic targets in metastatic breast cancer. Administration of DNase I is one strategy to eliminate NETs but long‐term treatment requires repeated injections and species‐specific versions of the enzyme. To enhance administration and therapeutic efficacy, we have developed an adeno‐associated virus (AAV) vector system for delivery of murine DNase I and addressed its potential to counteract cancer‐associated pathology in the murine MMTV‐PyMT model for metastatic mammary carcinoma. The AAV vector is comprised of capsid KP1 and an expression cassette encoding hyperactive murine DNase I (AAV‐mDNase I) under the control of a liver‐specific promotor. This AAV‐mDNase I vector could support elevated expression and serum activity of murine DNase I over at least 8 months. Neutrophil Gelatinase‐Associated Lipocalin (NGAL), a biomarker for kidney hypoperfusion that is upregulated in urine from MMTV‐PyMT mice, was suppressed in mice receiving AAV‐mDNase I compared to an AAV‐null control group. Furthermore, the proportion of mice that developed lung metastasis was reduced in the AAV‐mDNase I group. Altogether, our data indicate that AAV‐mDNase I has the potential to reduce cancer‐associated impairment of renal function and development of metastasis. We conclude that AAV‐mDNase I could represent a promising therapeutic strategy in metastatic breast cancer. [ABSTRACT FROM AUTHOR]

Simple Summary: Avian influenza (AI) is an infectious disease and could lead to death, health problems, and economic losses. Therefore, this study aimed to gather information about the compliance with and perceived effectiveness of AI control measures (applicable during high-risk periods in Flanders, North of Belgium, in 2021) by professional laying hen farmers and private bird keepers. Overall, self-reported compliance was high among professional laying hen farmers but much less among private bird keepers. Among private bird keepers, compliance and perceived effectiveness were lowest for confining the birds indoors, whereas for farmers, it was lowest for placing nets over the free-range. This study highlights the need for information campaigns explaining to private bird keepers, particularly the need for the various AI control measures imposed. Should these campaigns prove unsuccessful, local authorities might need to implement stricter enforcement of existing control measures or explore alternative ways to increase compliance, such as information posters in relevant stores for private bird keepers or meeting private bird keeper interest groups to provide broader support. Competent authorities of many countries, including Belgium, impose control measures (preventing wild bird access to feeders and water facilities, indoor confinement of captive birds, or fencing off outdoor ranges with nets) on professional and non-professional keepers of birds to prevent the spread of avian influenza (AI). Flemish laying hen farmers (FAR, n = 33) and private keepers of captive birds (PRI, n = 263) were surveyed about their opinion on and compliance with AI measures legally imposed during the most recent high-risk period before this survey in 2021. Participants answered questions on a 5-point Likert scale (1 = the worst, 3 = neutral, and 5 = the best). FAR indicated better compliance with the AI measures than PRI, except for net confinement. FAR indicated that they and other poultry farmers complied better with AI measures than PRI. Additionally, PRI indicated that they better complied than other PRI keepers. FAR regarded the AI measures as more effective than PRI. To prevent the spread of AI more effectively, national authorities could focus on information campaigns explaining to private bird keepers the need for the various control measures that they impose. If these campaigns fail, local authorities may need stricter enforcement or alternative ways to increase compliance. [ABSTRACT FROM AUTHOR]

Background: Acute kidney injury (AKI) is common in critical cases of coronavirus disease 2019 (COVID-19) and associated with worse outcome. Dysregulated neutrophil extracellular trap (NET) formation is one of several suggested pathophysiological mechanisms involved in the development of COVID-19 associated AKI. The corticosteroid dexamethasone was implemented as a standard treatment for severe COVID-19 as of June 2020. A sub-analysis of a prospective observational single center study was performed to evaluate the effect of corticosteroid treatment on AKI development and NET markers in critical cases of COVID-19. Results: Two hundred and ten adult patients admitted to intensive care at a tertiary level hospital due to respiratory failure or shock secondary to SARS-CoV-2-infection between March 13th 2020 and January 14th 2021 were included in the study. Ninety-seven of those did not receive corticosteroids. One hundred and thirteen patients were treated with corticosteroids [dexamethasone (n = 98) or equivalent treatment (n = 15)], but the incidence of AKI was assessed only in patients that received corticosteroids before any registered renal dysfunction (n = 63). Corticosteroids were associated with a lower incidence of AKI (19% vs 55.8%, p < 0.001). Fewer patients demonstrated detectable concentrations of extracellular histones in plasma when treated with corticosteroids (8.7% vs 43.1%; p < 0.001). Extracellular histones and in particular non-proteolyzed histones were observed more frequently with increasing AKI severity (p < 0.001). MPO-DNA was found in lower concentrations in patients that received corticosteroids before established renal dysfunction (p = 0.03) and was found in higher concentrations in patients with AKI stage 3 (p = 0.03). Corticosteroids did not ameliorate established AKI during the first week of treatment. Conclusion: Corticosteroid treatment in severe COVID-19 is associated with a lower incidence of AKI and reduced concentrations of NET markers in plasma. [ABSTRACT FROM AUTHOR]

Introduction: Crohn's disease (CD) is characterized by chronic inflammation and intestinal fibrosis leading to lifelong complications. However, the disease pathogenesis remains elusive, and the therapeutic options are limited. Here, we investigated the interaction between neutrophils and intestinal fibroblasts in the development of CD immunofibrosis, a disease mechanism predisposing to inflammatory and fibrotic complications. Methods: Peripheral neutrophils, enriched neutrophil extracellular traps (eNETs), serum, primary intestinal fibroblasts (PIFs) and intestinal biopsies from CD, ulcerative colitis (UC) patients, and healthy individuals (HI), were studied. Transcriptome analysis of neutrophils, multi-cytokine profiling and cell-based functional assays at mRNA/protein level were performed. Results: Compared to UC, PIFs from CD patients, independently to the presence of strictures, displayed a distinct pro-fibrotic phenotype characterized by negative Krüppellike Factor-2 (KLF2) and increased cellular communication network factor-2 (CCN2) expression leading to collagen production. In both UC and CD, PIFs-derived IL-8 acted as a culprit chemoattractant for neutrophils in the intestine, where CD neutrophils were accumulated close to fibrotic lesions. Functionally, only CD neutrophils via eNETs induced a CD-like phenotype in HI PIFs, suggesting their fibrotic plasticity. High IFNa in serum and IFα-responsive signature in peripheral neutrophils were observed in CD, distinguishing it from UC. Moreover, CD serum stimulated the release of fibrogenic eNETs from neutrophils in an IFNa-dependent manner, suggesting the priming role of IFNa in circulating neutrophils. Inhibition of eNETs or JAK signaling in neutrophils or PIFs prevented the neutrophil-mediated fibrotic effect on PIFs. Furthermore, both serum IFNa levels and mRNA levels of key IFN signaling components in neutrophils were wellcorrelated with CD severity. Conclusions: This study reveals the important role of the IFNa/neutrophil/fibroblast axis in CD immunofibrosis, suggesting candidate biomarkers and putative therapeutic targets. [ABSTRACT FROM AUTHOR]

Background: There is accumulating evidence regarding the benefits of the 5-HT3 receptor antagonist ondansetron for the treatment of critical illness due to its potential anti-inflammatory effect. This study attempted to determine the potential targets and molecular mechanisms of ondansetron's action against critical illnesses. Methods: A bioinformatics analysis of network pharmacology was conducted to demonstrate screening targets and the signaling pathways of ondansetron action against the most common critical illnesses such as acute kidney injury (AKI), sepsis, and acute respiratory distress syndrome (ARDS). Experiments of LPS- stimulated rat neutrophilswith ondansetron treatmentwere conducted to further validate the relevant hypothesis. Results: A total of 198, 111, and 26 primary causal targets were identified fromthe data for the action of ondansetron against AKI, sepsis, and ARDS respectively. We found that the pathway of neutrophil extracellular traps (NETs) formation is statistically significantly involved in the action of ondansetron against these three critical illnesses. In the pathway of NETs formation, the common drug- disease intersection targets in these three critical illnesses were toll-like receptor 8(TLR8),mitogen-activated protein kinase-14 (MAPK14), nuclear factor kappa-B1 (NFKB1), neutrophil elastase (NE), andmyeloperoxidase (MPO). Considering these bioinformatics findings, we concluded that ondansetron anti-critical illness effects are mechanistically and pharmacologically implicated with suppression of neutrophils-associated inflammatory processes. It was also showed that after treatment of LPS-stimulated rat neutrophils with ondansetron, the key proteins NE, MPO, and Peptide Arginine Deaminase 4 (PAD4) in the NETs formation were significantly reduced, and the inflammatory factors IL-6, IL-1β, TNF-α, and chemokine receptor (CXCR4) were also significantly decreased. Conclusion: The excessive formation of NETsmay have important research value in the development and progression of critical illness. Ondansetron may reduce excessive inflammatory injury in critical diseases by reducing the formation of NETs via influencing the five targets: TLR8, NFKB1, MAPK14, NE, and MPO. Ondansetron and these primary predictive biotargets may potentially be used to treat critical illness in future clinical practice. [ABSTRACT FROM AUTHOR]

B-1a cells, a regulatory subset of B lymphocytes, produce natural IgM and interleukin-10. Neutrophil extracellular traps (NETs) play a crucial role in pathogen defense, but their excessive formation during sepsis can cause further inflammation and tissue damage. In sepsis, extracellular cold-inducible RNA-binding protein (eCIRP), a damage-associated molecular pattern, is released to induce NET formation. We hypothesize that B-1a cells clear NETs to prevent sepsis-induced injury. Sepsis in mice was induced by injecting 1 × 107 and 5 × 107 colony-forming units of Escherichia coli intraperitoneally. After 4 and 20 h, we assessed the number of B-1a cells in the peritoneal cavity using flow cytometry. Our results showed that the number of peritoneal B-1a cells was significantly decreased in E. coli sepsis mice. Importantly, replenishing B-1a cells via intraperitoneal injection in sepsis mice significantly decreased NETs in peritoneal neutrophils. We also observed a decrease in serum inflammation and injury markers and a significant increase in the overall survival rate in B-1a cell–treated septic mice. To understand the mechanism, we cocultured bone marrow–derived neutrophils with peritoneal B-1a cells in a contact or noncontact condition using an insert and stimulated them with eCIRP. After 4 h, we found that eCIRP significantly increased NET formation in bone marrow–derived neutrophils. Interestingly, we observed that B-1a cells inhibited NETs by 67% in a contact-dependent manner. Surprisingly, when B-1a cells were cultured in inserts, there was no significant decrease in NET formation, suggesting that direct cell-to-cell contact is crucial for this inhibitory effect. We further determined that B-1a cells promoted NET phagocytosis, and this was mediated through natural IgM, as blocking the IgM receptor attenuated the engulfment of NETs by B-1a cells. Finally, we identified that following their engulfment, NETs were localized into the lysosomal compartment for lysis. Thus, our study suggests that B-1a cells decrease NET content in eCIRP-treated neutrophils and E. coli sepsis mice. [ABSTRACT FROM AUTHOR]

Ileal (I) and pancreatic (Pan) neuroendocrine tumors (NETs) are among the most common digestive neuroendocrine neoplasms (NENs). Coexisting NETs at both sites are rare, and establishing the primary or metastatic nature of the two lesions may be crucial for the appropriate treatment. We reviewed all the clinical reports of patients with INETs or PanNETs, diagnosed and treated in our ENETS Center of Excellence between 2012 and 2022. We selected patients with a history of synchronous or metachronous neuroendocrine (NE) lesions at the ileum and pancreas. For those with available histological samples from both sites, an immunohistochemistry (IHC) analysis for CDX2, Islet1, and serotonin has been performed. We found seven patients with NET in both the ileum and pancreas. F to M ratio was 4:3, and the median age at first diagnosis was 54 years (42–79). Five cases had synchronous lesions; in 2 cases, PanNETs were diagnosed respectively 8 and 56 months, after INETs. In four patients, with available histological samples from both the sites, a pathologic review and the IHC analysis have been performed, identifying three different scenarios: (i) primary INET metastatic to the pancreas, (ii) primary PanNET metastatic to the ileum, and (iii) synchronous primary PanNET and INET. In our experience, coexisting ileal and pancreatic NENs are rare occurrences. A multidisciplinary evaluation case-by-case and, whenever feasible, a comprehensive histopathological examination are needed to distinguish between metastatic and primary disease, in order to properly treat the patient. [ABSTRACT FROM AUTHOR]

Abstract Neutrophil extracellular traps (NETs) have been implicated in the pathology of various inflammatory conditions. In cancer, NETs have been demonstrated to induce systemic inflammation, impair peripheral vessel and organ function and promote metastasis. Here we show that the plasma level of NETs is significantly higher in patients with metastatic breast cancer compared to those with local disease, or those that were considered cured at a 5‐year follow‐up, confirming NETs as interesting therapeutic targets in metastatic breast cancer. Administration of DNase I is one strategy to eliminate NETs but long‐term treatment requires repeated injections and species‐specific versions of the enzyme. To enhance administration and therapeutic efficacy, we have developed an adeno‐associated virus (AAV) vector system for delivery of murine DNase I and addressed its potential to counteract cancer‐associated pathology in the murine MMTV‐PyMT model for metastatic mammary carcinoma. The AAV vector is comprised of capsid KP1 and an expression cassette encoding hyperactive murine DNase I (AAV‐mDNase I) under the control of a liver‐specific promotor. This AAV‐mDNase I vector could support elevated expression and serum activity of murine DNase I over at least 8 months. Neutrophil Gelatinase‐Associated Lipocalin (NGAL), a biomarker for kidney hypoperfusion that is upregulated in urine from MMTV‐PyMT mice, was suppressed in mice receiving AAV‐mDNase I compared to an AAV‐null control group. Furthermore, the proportion of mice that developed lung metastasis was reduced in the AAV‐mDNase I group. Altogether, our data indicate that AAV‐mDNase I has the potential to reduce cancer‐associated impairment of renal function and development of metastasis. We conclude that AAV‐mDNase I could represent a promising therapeutic strategy in metastatic breast cancer.

The results of recent studies show that tumor biology, coagulation activation, and inflammatory reactions profoundly contribute to the thrombosis pathogenesis in cancer as well as tumor progression, metastasis, and developing chemoresistance. Cancer is an independent predictor of thrombosis. During carcinogenesis, tumor cells express proinflammatory cytokines, proangiogenic and procoagulant factors, and also stimulate other cells to express various components promoting emerging thromboinflammation. The discovery of neutrophil extracellular traps (NETs) provides an opportunity to take a new look at biology and a role neutrophils may play in thromboinflammation and tumorigenesis. The close interplay between tumor cells, tumor-associated neutrophils and NETs as well as other players in the tumor microenvironment underlies activation of thromboinflammation in cancer patients not only resulting in thrombus formation, but also promoting tumor growth and dissemination.

Abstract Background Acute kidney injury (AKI) is common in critical cases of coronavirus disease 2019 (COVID-19) and associated with worse outcome. Dysregulated neutrophil extracellular trap (NET) formation is one of several suggested pathophysiological mechanisms involved in the development of COVID-19 associated AKI. The corticosteroid dexamethasone was implemented as a standard treatment for severe COVID-19 as of June 2020. A sub-analysis of a prospective observational single center study was performed to evaluate the effect of corticosteroid treatment on AKI development and NET markers in critical cases of COVID-19. Results Two hundred and ten adult patients admitted to intensive care at a tertiary level hospital due to respiratory failure or shock secondary to SARS-CoV-2-infection between March 13th 2020 and January 14th 2021 were included in the study. Ninety-seven of those did not receive corticosteroids. One hundred and thirteen patients were treated with corticosteroids [dexamethasone (n = 98) or equivalent treatment (n = 15)], but the incidence of AKI was assessed only in patients that received corticosteroids before any registered renal dysfunction (n = 63). Corticosteroids were associated with a lower incidence of AKI (19% vs 55.8%, p

One of the important problems of medicine is the search for new reliable markers of inflammation that would allow us to determine the type of inflammatory process. The aim of the study was to identify specific markers of infectious and aseptic inflammation based on the analysis of morphological variants of neutrophil extracellular traps (NETs). The study included 26 patients with various nosological forms of inflammation in the abdominal cavity (12 with acute appendicitis, 8 with acute cholecystitis, 6 with a diagnosis of pancreatitis/ pancreonecrosis) after surgery. The study also included 20 patients with post-COVID and a group of 10 volunteers no clinical manifestations of the disease, but at the same time had contacts with flu patients. Neutrophils were isolated using gradient centrifugation. Fluorescence microscopies with the dye SYBR Green (JSC “Evrogen”, Russia) were used for NET visualization and counting. NETs in the morphological form of neutrophils web structure were found in the blood of surgical patients with acute appendicitis who had a favorable course of the postoperative period. In a group of volunteers who were exposed to influenza but did not have symptoms of an infectious disease, we also found neutrophils web structure. In all patients with abdominal inflammation complicated by abdominal abscess, in addition to neutrophil web structure, abnormal forms of NETs were recorded, in particular, NETs in the form of single filaments. In the post-COVID patients an absolute absence of neutrophilis web structure was revealed. In all post-COVID patients, NETs are found only in the form of single filaments. The results of subsequent experiments showed that collagen peptides are inducers of the formation of NETs in the form of single filaments. The detection of neutrophils web structure is a sign of an infectious inflammatory process. NETs in the morphological form of single filaments are markers of aseptic inflammation, as well as a sign of endothelial damage.

Aim. To evaluate the levels of MPO-DNA complex in patients with systemic lupus erythematosus (SLE) and its association with the presence of lupus nephritis (LN). Materials and methods. The study included 77 patients with SLE, of whom 30 had SLE without anti phospholipid syndrome (APS), 47 had SLE with APS, and 20 were healthy individuals serving as the control group. The MPO-DNA complex in the serum was investigated using ELISA. Results. The levels of MPO-DNA complex in serum were significantly higher in patients with SLE compared to healthy controls (p=0.001). Among the patients with SLE, 30 (39%) had elevated levels of MPO-DNA complex. The presence of elevated MPO-DNA complex was significantly associated with the presence of a history of LN (p=0.009). Moreover, among the patients included in the study, 20 had active LN, and patients with elevated MPO-DNA complex levels were more likely to have active LN than patients without elevated MPO-DNA complex concentrations [12 (40%) of 30 vs 8 (17%) of 47, χ2=5.029; p=0.034]. An association was found between elevated levels of MPO-DNA complex and the presence of proteinuria, hematuria, cellular hematic/granular casts and aseptic leukocyturia. A direct correlation of MPO-DNA complex with SLEDAI-R was found in patients with active LN (rs=0.497; p=0.026). Conclusion. Elevated levels of MPO-DNA complex were detected in 39% of patients with SLE. These patients had a higher prevalence of LN in their medical history and at the time of inclusion in the study. The correlation between MPO-DNA complex levels and the activity of LN according to SLEDAI-R indicates the potential role of MPO-DNA complex as a biomarker for assessing the activity of renal damage in SLE.

Besnoitia besnoiti is an obligate intracellular apicomplexan parasite and the causal agent of bovine besnoitiosis. Bovine besnoitiosis has a considerable economic impact in Africa and Asia due to reduced milk production, abortions, and bull infertility. In Europe, bovine besnoitiosis is classified as an emerging disease. Polymorphonuclear neutrophils (PMN) are one of the most abundant leukocytes in cattle blood and amongst the first immunological responders toward invading pathogens. In the case of B. besnoiti, bovine PMN produce reactive oxygen species (ROS), release neutrophil extracellular traps (NETs), and show increased autophagic activities upon exposure to tachyzoite stages. In that context, the general processes of NETosis and autophagy were previously reported as associated with AMP-activated protein kinase (AMPK) activation. Here, we study the role of AMPK in B. besnoiti tachyzoite-induced NET formation, thereby expanding the analysis to both upstream proteins, such as the calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK), and downstream signaling and effector molecules, such as the autophagy-related proteins ULK-1 and Beclin-1. Current data revealed early AMPK activation (<30 min) in both B. besnoiti-exposed and AMPK activator (AICAR)-treated bovine PMN. This finding correlated with upstream responses on the level of CAMKK activation. Moreover, these reactions were accompanied by an augmented autophagic activity, as represented by enhanced expression of ULK-1 but not of Beclin-1. Referring to neutrophil effector functions, AICAR treatments induced both AMPK phosphorylation and NET formation, without affecting cell viability. In B. besnoiti tachyzoite-exposed PMN, AICAR treatments failed to affect oxidative responses, but led to enhanced NET formation, thereby indicating that AMPK and autophagic activation synergize with B. besnoiti-driven NETosis. [ABSTRACT FROM AUTHOR]

This article discusses the involvement of neutrophils in the lungs during the recovery phase of COVID-19. The study used a mouse model to investigate changes in neutrophil phenotype and their association with lung injury. The findings showed persistent recruitment of neutrophils and the formation of neutrophil extracellular traps (NETs) in the lungs for up to 30 days after infection, which correlated with lung fibrosis and inflammation. The study suggests that neutrophil activation may contribute to pulmonary complications in COVID-19 survivors and highlights the need for further research to develop effective therapeutic strategies. [Extracted from the article]

The utilization of platelet-rich plasma (PRP) has exhibited potential as a therapeutic approach for the management of diabetic foot ulcers (DFUs). However, it is currently not well understood how the diabetic environment may influence PRP-derived exosomes (PRP-Exos) and their potential impact on neutrophil extracellular traps (NETs). This study aims to investigate the effects of the diabetic environment on PRP-Exos, their communication with neutrophils, and the subsequent influence on NETs and wound healing. Through bulk-seq and Western blotting, we confirmed the increased expression of MMP-8 in DFUs. Additionally, we discovered that miRNA-26b-5p plays a significant role in the communication between DFUs and PRP-Exos. In our experiments, we found that PRP-Exos miR-26b-5p effectively improved diabetic wound healing by inhibiting NETs. Further tests validated the inhibitory effect of miR-26b-5p on NETs by targeting MMP-8. Both in vitro and in vivo experiments showed that miRNA-26b-5p from PRP-Exos promoted wound healing by reducing neutrophil infiltration through its targeting of MMP-8. This study establishes the importance of miR-26b-5p in the communication between DFUs and PRP-Exos, disrupting NETs formation in diabetic wounds by targeting MMP-8. These findings provide valuable insights for developing novel therapeutic strategies to enhance wound healing in individuals suffering from DFUs. The PRP-Exos demonstrate an inhibitory effect on the formation of neutrophil extracellular traps (NETs) and facilitate the healing of diabetic wounds, potentially through the delivery of miR-26b-5p to neutrophils targeting MMP-8. [Display omitted] • PRP-Exos miR-26b-5p improves DFU healing by inhibiting NETs. • miR-26b-5p targets MMP-8, reducing neutrophil infiltration in wounds. • Study highlights miR-26b-5p's role in PRP-Exos and neutrophil communication. [ABSTRACT FROM AUTHOR]

Inflammation including immunothrombosis by neutrophil extracellular traps (NETs) has important implications in acute ischemic stroke and can affect reperfusion status, susceptibility to stroke associated infections (SAI) as well as functional clinical outcome. NETs were shown to be prevalent in stroke thrombi and NET associated markers were found in stroke patients' blood. However, little is known whether blood derived NET markers reflect the amount of NETs in thrombi. Conclusions from blood derived markers to thrombus composition might open avenues for novel strategies in diagnostic and therapeutic approaches. We prospectively recruited 166 patients with acute ischemic stroke undergoing mechanical thrombectomy between March 2018 and May 2021. Available thrombi (n = 106) were stained for NET markers DNA-histone-1 complexes and myeloperoxidase (MPO). Cell free DNA (cfDNA), deoxyribonuclease (DNase) activity, MPO-histone complexes and a cytokine-panel were measured before thrombectomy and after seven days. Clinical data, including stroke etiology, reperfusion status, SAI and functional outcome after rehabilitation, were collected of all patients. NET markers were present in all thrombi. At onset the median concentration of cfDNA in blood was 0.19 µg/ml increasing to 0.30 µg/ml at 7 days. Median DNase activity at onset was 4.33 pmol/min/ml increasing to 4.96 pmol/min/ml at 7 days. Within thrombi DNA-histone-1 complexes and MPO correlated with each other (ρ = 0.792; p < 0.001). Moreover, our study provides evidence for an association between the amount of NETs and endogenous DNase activity in blood with amounts of NETs in cerebral thrombi. However, these associations need to be confirmed in larger cohorts, to investigate the potential clinical implications for individualized therapeutic and diagnostic approaches in acute ischemic stroke. [ABSTRACT FROM AUTHOR]

With the recent discovery of their ability to produce neutrophil extracellular traps (NETs), neutrophils are increasingly appreciated as active participants in infection and inflammation. NETs are characterized as large, web‐like networks of DNA and proteins extruded from neutrophils, and there is considerable interest in how these structures drive disease in humans. Advancing research in this field is contingent on developing novel tools for quantifying NETosis. To this end, we have developed a 7‐marker flow cytometry panel for analyzing NETosis on human peripheral neutrophils following in vitro stimulation, and in fresh circulating neutrophils under inflammatory conditions. This panel was optimized on neutrophils isolated from whole blood and analyzed fresh or in vitro stimulated with phorbol 12‐myristate 13‐acetate (PMA) or ionomycin, two known NET‐inducing agonists. Neutrophils were identified as SSChighFSChighCD15+CD66b+. Neutrophils positive for amine residues and 7‐Aminoactinomycin D (7‐AAD), our DNA dye of choice, were deemed necrotic (Zombie‐NIR+7‐AAD+) and were removed from downstream analysis. Exclusion of Zombie‐NIR and positivity for 7‐AAD (Zombie‐NIRdim7‐AAD+) was used here as a marker of neutrophil‐appendant DNA, a key feature of NETs. The presence of two NET‐associated proteins – myeloperoxidase (MPO) and neutrophil elastase (NE) – were utilized to identify neutrophil‐appendant NET events (SSChighFSChighCD15+CD66b+Zombie NIRdim7‐AAD+MPO+NE+). We also demonstrate that NETotic neutrophils express citrullinated histone H3 (H3cit), are concentration‐dependently induced by in vitro PMA and ionomycin stimulation but are disassembled with DNase treatment, and are present in both chronic and acute inflammation. This 7‐color flow cytometry panel provides a novel tool for examining NETosis in humans. [ABSTRACT FROM AUTHOR]

In recent years, substantial advancements have been made in understanding the pathophysiology of ischemic stroke. Despite these developments, therapeutic options for cerebral ischemia remain limited due to stringent time windows and various contraindications. Consequently, there has been a concentrated effort to elucidate the underlying mechanisms of cerebral ischemic injury. Emerging research indicates that neutrophil extracellular traps (NETs) exacerbate inflammation and damage in ischemic brain tissue, contributing to neuronal cell death. The inhibition of NETs has shown potential in preventing thrombosis and the infiltration of immune cells. Central to the formation of NETs are P-selectin and its ligand, P-selectin glycoprotein ligand-1 (PSGL-1), which represent promising therapeutic targets. This review explores the detrimental impact of P-selectin, PSGL-1, and NETs on cerebral ischemia. Additionally, it delineates the processes by which P-selectin and PSGL-1 stimulate NETs production and provides evidence that blocking these molecules reduces NETs formation. This novel insight highlights a potential therapeutic avenue that warrants further investigation by researchers in the field. [ABSTRACT FROM AUTHOR]

Background: An autoimmune disease that impacts both articular and extra-articular organs (e.g., eye, skin, and nervous system), progressive systemic rheumatoid arthritis (RA) is a pathological condition. We aimed to measure the serum level of neutrophil extracellular traps (NETs) in RA patients and to detect the correlation between NET level and RA activity. Also to study the relation between NET level and cardiovascular affection in RA patients by measuring the carotid intima media thickness. Patients and methods: This study was conducted on 50 RA patients diagnosed according to the American College of Rheumatology and European League Against Rheumatism 2010 diagnostic criteria for RA, and 50 apparently healthy volunteers matched with patients in sex and age for evaluation of the NET level. All patients underwent the following: full clinical assessment, laboratory investigations, radiographic assessment and wrist and measurement of carotid intima media thickness by ultrasound. Results: There was elevation in total cholesterol, triglycerides, LDL levels and reduction in HDL level in patients. There was increased level of MPO level in RA patients' group with significant difference between the RA and control group (P<0.05). There was significant positive correlation between MPO level and clinical, laboratory and radiological findings of the patients (P<0.05). Conclusion: The serum level of NETs is increased in RA patients and correlated with rheumatoid disease activity detected by MSUS and DAS -28. Also, the serum level of NETs could be considered a useful biomarker for the early prediction of subclinical atherosclerosis and cardiovascular affection in RA patients. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is characterized by chronic, low‐grade inflammation. This state may be related to the heightened production of neutrophil extracellular traps (NETs) induced by high glucose (HG). Human cathelicidin antimicrobial peptide (LL37) is an endogenous ligand of G protein‐coupled chemoattractant receptor formyl peptide receptor 2 (FPR2), expressed on neutrophils and facilitating the formation and stabilization of the structure of NETs. In this study, we detected neutrophils cultured under different conditions, the retinal tissue of diabetic mice, and fibrovascular epiretinal membranes (FVM) samples of patients with proliferative diabetic retinopathy (PDR) to explore the regulating effect of LL37/FPR2 on neutrophil in the development of NETs during the process of DR. Specifically, HG or NG with LL37 upregulates the expression of FPR2 in neutrophils, induces the opening of mitochondrial permeability transition pore (mPTP), promotes the increase of reactive oxygen species and mitochondrial ROS, and then leads to the rise of NET production, which is mainly manifested by the release of DNA reticular structure and the increased expression of NETs‐related markers. The PI3K/AKT signaling pathway was activated in neutrophils, and the phosphorylation level was enhanced by FPR2 agonists in vitro. In vivo, increased expression of NETs markers was detected in the retina of diabetic mice and in FVM, vitreous fluid, and serum of PDR patients. Transgenic FPR2 deletion led to decreased NETs in the retina of diabetic mice. Furthermore, in vitro, inhibition of the LL37/FPR2/mPTP axis and PI3K/AKT signaling pathway decreased NET production induced by high glucose. These results suggested that FPR2 plays an essential role in regulating the production of NETs induced by HG, thus may be considered as one of the potential therapeutic targets. [ABSTRACT FROM AUTHOR]

Introduction: This study assesses the accuracy of neutrophil activation markers, including neutrophil extracellular traps (NETs) and calprotectin, as biomarkers of disease activity in patients with established rheumatoid arthritis (RA). We also analyse the relationship between NETs and various types of therapies as well as their association with autoimmunity. Methods: Observational cross-sectional study of patients with RA receiving treatment with biological disease-modifying antirheumatic drugs or Janus kinase inhibitors (JAK-inhibitors) for at least 3 months. Plasma calprotectin levels were measured using an enzyme-linked immunosorbent assay test kit and NETs by measuring their remnants in plasma (neutrophil elastase-DNA and histone-DNA complexes). We also assessed clinical disease activity, joint ultrasound findings and autoantibody status [reumatoid factor (RF), anti-citrullinated peptide/protein antibodies (ACPAs) and anti-carbamylated protein (anti-CarP)]. Associations between neutrophilic biomarkers and clinical or ultrasound scores were sought using correlation analysis. The discriminatory capacity of both neutrophilic biomarkers to detect ultrasound synovitis was analysed through receiver-operating characteristic (ROC) curves. Results: One hundred fourteen patients were included. Two control groups were included to compare NET levels. The active control group consisted of 15 patients. The second control group consisted of 30 healthy subjects. Plasma NET levels did not correlate with clinical disease status, regardless of the clinic index analysed or the biological therapy administered. No significant correlation was observed between NET remnants and ultrasound synovitis. There was no correlation between plasma NET and autoantibodies. In contrast, plasma calprotectin positively correlated with clinical parameters (swollen joint count [SJC] rho = 0.49; P < 0.001, Clinical Disease Activity Index [CDAI] rho = 0.30; P < 0.001) and ultrasound parameters (rho > 0.50; P < 0.001). Notably, this correlation was stronger than that observed with acute phase reactants. Conclusion: While NET formation induced by neutrophils may play a role in RA pathogenesis, our study raises questions about the utility of NET remnants in peripheral circulation as a biomarker for inflammatory activity. In contrast, this study strongly supports the usefulness of calprotectin as a biomarker of inflammatory activity in patients with RA. [ABSTRACT FROM AUTHOR]

Influenza A virus (IAV) infections in swine are usually subclinical, but they can reach high morbidity rates. The mortality rate is normally low. In this study, six vaccinated, spontaneously deceased sows revealed IAV infection and enhanced neutrophilic bronchopneumonia with unexpectedly large numbers of infiltrating eosinophils. The purpose of this study was to characterize these lung lesions with special emphasis on the phenotypes of inflammatory cells, the presence of eosinophilic peroxidase (EPO), and neutrophil extracellular traps (NETs). The number of Sirius red-stained eosinophils was significantly higher in the lungs of IAV-infected sows compared to healthy pigs, indicating a migration of eosinophils from blood vessels into the lung tissue stimulated by IAV infection. The detection of intra- and extracellular EPO in the lungs suggests its contribution to pulmonary damage. The presence of CD3+ T lymphocytes, CD20+ B lymphocytes, and Iba-1+ macrophages indicates the involvement of cell-mediated immune responses in disease progression. Furthermore, high numbers of myeloperoxidase-positive cells were detected. However, DNA-histone-1 complexes were reduced in IAV-infected sows, leading to the hypothesis that NETs are not formed in the IAV-infected sows. In conclusion, our findings in the lungs of IAV-infected vaccinated sows suggest the presence of so far unreported field cases of vaccine-associated enhanced respiratory disease. [ABSTRACT FROM AUTHOR]

Neuroendocrine tumors (NETs) represent a diverse group of neoplasms originating from neuroendocrine cells, presenting varied clinical behaviors and posing significant challenges in management. This review explores the emerging roles of receptor tyrosine kinases (RTKs) in the pathogenesis and progression of NETs, including vascular endothelial growth factor receptors (VEGFRs), insulin-like growth factor receptors (IGF-1R), RET, epidermal growth factor receptor (EGFR), and ALK. The dysregulation of RTK signaling pathways contributes to key cellular processes such as proliferation, survival, and invasion in NETs. We discuss the potential of targeting RTKs as therapeutic strategies in NETs, with a focus on recent developments in RET inhibitors and the therapeutic implications of RTK alterations. [ABSTRACT FROM AUTHOR]

Simple Summary: Among other limitations, the currently available vaccines against paratuberculosis do not offer complete protection against infection, and further vaccine development is limited by a lack of understanding of the mechanisms behind vaccine-induced protection. In this regard, the most recent studies have demonstrated that neutrophil function can be modulated through vaccination against several pathogens, including Mycobacterium avium subspecies paratuberculosis (Map). However, this modulation has not been described in ruminants, which are the natural hosts of Map. In the present work, the effect of vaccination on the neutrophil response against Map was assessed in goats using the only available vaccine against small ruminant paratuberculosis, Gudair®. No differences were found in the ex vivo response of neutrophils isolated from non-vaccinated and vaccinated animals, which suggests that the protection conferred by this heat-inactivated vaccine is based on mechanisms other than neutrophil modulation. It is possible that neutrophil modulation depends largely on the intensity of the immune response elicited by the vaccine employed or the antigen dose, as the previous reports which observed this modulation used live attenuated vaccines or were performed in laboratory animals using experimental vaccines. Neutrophils are believed to play a role in the initial stages of paratuberculosis, and it has recently been demonstrated that vaccination can modulate their function via priming or through epigenetic and metabolic reprogramming (training). Modulation of the neutrophil response against Mycobacterium avium subspecies paratuberculosis (Map) through vaccination has been demonstrated in a rabbit model but not in ruminants. Therefore, in the present work, the effect of vaccination on the response of caprine neutrophils against Map was studied. Neutrophils were isolated from non-vaccinated (n = 7) and Gudair®-vaccinated goat kids (n = 7), before vaccination and 30 days post-vaccination. Then, several neutrophil functions were quantified ex vivo: cell-free and anchored neutrophil extracellular trap (NET) release, phagocytosis, and the differential expression of several cytokines and TLR2. The induction of cell-free NETosis and TLR2 expression by Map is reported for the first time. However, vaccination showed no significant effect on any of the functions studied. This suggests that the protection conferred by Gudair® vaccination is based on mechanisms that are independent of the neutrophil function modulation. Further research into the impact of alternative vaccination strategies or the paratuberculosis infection stage on ruminant neutrophil function could provide valuable insights into its role in paratuberculosis. [ABSTRACT FROM AUTHOR]

Binge drinking in obese patients positively correlates with accelerated liver damage and liver-related death. However, the underlying mechanism and the effect of alcohol use on the progression of metabolic-dysfunction-associated steatotic liver disease (MASLD) remain unexplored. Here, we show that short-term feeding of a metabolic-dysfunction-associated steatohepatitis (MASH) diet plus daily acute alcohol binges for three days induce liver injury and activation of the NLRP3 inflammasome. We identify that a MASH diet plus acute alcohol binges promote liver inflammation via increased infiltration of monocyte-derived macrophages, neutrophil recruitment, and NET release in the liver. Our results suggest that both monocyte-derived macrophages and neutrophils are activated via NLRP3, while the administration of MCC950, an NLRP3 inhibitor, dampens these effects.In this study, we reveal important intercellular communication between hepatocytes and neutrophils. We discover that the MASH diet plus alcohol induces IL-1β via NLRP3 activation and that IL-1β acts on hepatocytes and promotes the production of CXCL1 and LCN2. In turn, the increase in these neutrophils recruits chemokines and causes further infiltration and activation of neutrophils in the liver. In vivo administration of the NLRP3 inhibitor, MCC950, improves the early phase of MetALD by preventing liver damage, steatosis, inflammation, and immune cells recruitment. [ABSTRACT FROM AUTHOR]

Introduction: The prevalence of diabetes mellitus and its sequelae has been on the rise, and diabetic foot ulcer (DFU) is the leading cause of non-traumatic lower limb amputation globally. The rising occurrence and financial burden associated with DFU necessitate improved clinical assessment and treatment. Diabetes has been found to enhance the formation of neutrophil extracellular traps (NETs) by neutrophils, and excessive NETs have been implicated in tissue damage and impaired wound healing. However, there is as yet insufficient evidence to clarify the value of NETs in assessing and predicting outcomes of DFU. Methods: We designed this prospective study with three cohorts formed from type 2 diabetes mellitus (T2DM) patients with DFU (n = 200), newly diagnosed T2DM patients (n = 42), and healthy donors (n = 38). Serum levels of NETs were detected for all groups, and the prognostic value for DFU-related amputation was analyzed. Results: The results showed that serum NET levels of the DFU group were significantly higher than in the T2DM group (P < 0.05), which also had significantly elevated serum NET levels compared to healthy donors (P < 0.05). Multivariate Cox regression showed that serum NET levels, diabetic foot surgical history, and Wagner grade were the risk factors for amputation (P < 0.05), and these three variables also exhibited the highest coefficient values in additional Lasso Cox regression. For patients with DFU, Kaplan-Meier curves showed that high serum NET levels associated with higher amputation probability (HR = 0.19, P < 0.01) and ROC curve based on NET value showed good validity for amputation (AUC: 0.727, CI 0.651–0.803). Conclusion: Elevated serum NET levels serve as an easily accessible serological prognostic marker for assessing the risk of DFU-related amputation, thereby offering evaluation metrics for healthcare providers. Further investigations are necessary to understand the mechanisms driving this relationship. [ABSTRACT FROM AUTHOR]

Abstract Increased circulating histones correlate with sepsis severity and are a potential therapeutic target. Pre‐clinical studies showed benefit with a histone‐neutralizing polyanion molecule (STC3141). We aimed to investigate the safety, tolerability, and pharmacokinetics of STC3141 in critically ill patients with sepsis. We studied 26 patients with sepsis divided into four cohorts of one, five, ten, and ten subjects, respectively. We conducted a dose‐adjusted, open‐label study to determine the safety, tolerability, and pharmacokinetics of STC3141 administered as an IV infusion for up to 72 h, with rate adjusted to estimated creatinine clearance. Four steady‐state concentrations were targeted. Twenty of the 26 subjects (77%) in the study experienced at least one adverse event (AE). The most frequently reported study drug‐related AE was a mildly prolonged aPTT (four events). Only one AE (pulmonary hemorrhage) led to discontinuation of the drug. After excluding patients receiving renal replacement therapy (RRT) patients, clearance ranged from 3.3 to 4.2 L/h across cohorts and was essentially completely renal in nature. Half‐life values ranged from 5 to 7 h. The mean (±SD) terminal half‐life for non‐RRT subjects and for whom it was possible to calculate was approximately 9 (±4.77) h but increased to 19 (±7.94) h for subjects on RRT. Overall, 18 (69.2%) patients completed the study to day eight in the ICU, and 22 (84.6%) survived to 28 days. STC3141 administration appeared to have an acceptable degree of safety and tolerability and expected pharmacokinetics. Cautious, larger randomized efficacy trials in sepsis appear justified.

IntroductionCrohn’s disease (CD) is characterized by chronic inflammation and intestinal fibrosis leading to lifelong complications. However, the disease pathogenesis remains elusive, and the therapeutic options are limited. Here, we investigated the interaction between neutrophils and intestinal fibroblasts in the development of CD immunofibrosis, a disease mechanism predisposing to inflammatory and fibrotic complications.MethodsPeripheral neutrophils, enriched neutrophil extracellular traps (eNETs), serum, primary intestinal fibroblasts (PIFs) and intestinal biopsies from CD, ulcerative colitis (UC) patients, and healthy individuals (HI), were studied. Transcriptome analysis of neutrophils, multi-cytokine profiling and cell-based functional assays at mRNA/protein level were performed.ResultsCompared to UC, PIFs from CD patients, independently to the presence of strictures, displayed a distinct pro-fibrotic phenotype characterized by negative Krüppellike Factor-2 (KLF2) and increased cellular communication network factor-2 (CCN2) expression leading to collagen production. In both UC and CD, PIFs-derived IL-8 acted as a culprit chemoattractant for neutrophils in the intestine, where CD neutrophils were accumulated close to fibrotic lesions. Functionally, only CD neutrophils via eNETs induced a CD-like phenotype in HI PIFs, suggesting their fibrotic plasticity. High IFNa in serum and IFΝ-responsive signature in peripheral neutrophils were observed in CD, distinguishing it from UC. Moreover, CD serum stimulated the release of fibrogenic eNETs from neutrophils in an IFNa-dependent manner, suggesting the priming role of IFNa in circulating neutrophils. Inhibition of eNETs or JAK signaling in neutrophils or PIFs prevented the neutrophil-mediated fibrotic effect on PIFs. Furthermore, both serum IFNa levels and mRNA levels of key IFN signaling components in neutrophils were wellcorrelated with CD severity.ConclusionsThis study reveals the important role of the IFNa/neutrophil/fibroblast axis in CD immunofibrosis, suggesting candidate biomarkers and putative therapeutic targets.

Osteosarcoma (OS) has strong invasiveness, early metastasis, high drug resistance, and poor prognosis. At present, OS still lacks reliable biomarkers, which makes early diagnosis of OS more difficult. AOC3 is highly expressed in OS and highly correlated with lung metastasis. qRT-PCR could identify mRNA levels of genes. Immunohistochemistry and Western blot assays could detect protein levels. Immunofluorescence and ELISA assays were applied to evaluate the activation of neutrophils. Additionally, transwell and wound healing assays evaluated cell migration and invasion abilities. Tube formation and sphere-forming assays were applied to detect the angiogenesis. C57BL/6 mice were injected with OS cells to establish a xenograft tumor model to observe the lung metastasis of OS. Flow cytometry is used to evaluate the ability of tumor cells to recruit neutrophils. AOC3 was significantly overexpressed in OS, and down-regulation of AOC3 could inhibit OS migration, invasion, and angiogenesis. AOC3 could increase tumor development and lung metastasis of OS in vivo experiments. The promoting effect of AOC3 on tumor lung metastasis was achieved by recruiting tumor neutrophils. Activated NETs could up-regulate the metastatic ability of OS cells. Tumor neovascularization also played a role in metastasis, and AOC3 supported tumor neovascularization. AOC3 accelerates lung metastasis of OS by recruiting tumor-related neutrophils and utilizing NETs and tumor vascularization formation.

Background: Interleukin-6-receptor inhibition with tocilizumab improves myocardial salvage in patients with ST-segment elevation myocardial infarction (STEMI). Reduced levels of neutrophil extracellular traps (NETs), which consist of nuclear material studded with proteins released upon neutrophil activation, might contribute to this effect. Objectives: The purpose of this study was to evaluate the effect of tocilizumab on NETs and investigate the association between NETs and myocardial injury in patients with STEMI. Methods: In the ASSAIL-MI study, 199 patients with STEMI were randomized to tocilizumab or placebo during percutaneous coronary intervention. In this substudy, we analyzed blood levels of the NET markers double-stranded deoxyribonucleic acid (dsDNA), myeloperoxidase-DNA, and citrullinated histone 3 (H3Cit) at admission and after 24 hours and 3 to 7 days. In a subgroup of patients, we assessed regulation of transcripts related to the formation of NETs. We also investigated associations between NET markers and the myocardial salvage index (MSI). Results: All NET markers were lower in the tocilizumab group than in the placebo group at 3 to 7 days (all P

Abstract Background Integrating radioactive and optical imaging techniques can facilitate the prognosis and surgical guidance for cancer patients. Using a single dual-labeled tracer ensures consistency in both imaging modalities. However, developing such molecule is challenging due to the need to preserve the biochemical properties of the tracer while introducing bulky labeling moieties. In our study, we designed a trifunctional chelate that facilitates the coupling of the targeting vector and fluorescent dye at opposite sites to avoid undesired steric hindrance effects. The synthesis of the trifunctional chelate N3-Py-DOTAGA-(tBu)3 (7) involved a five-step synthetic route, followed by conjugation to the linear peptidyl-resin 8 through solid-phase synthesis. After deprotection and cyclization, the near-infrared fluorescent dye sulfo-Cy.5 was introduced using copper free click chemistry, resulting in eTFC-01. Subsequently, eTFC-01 was labeled with [111In]InCl3. In vitro assessments of eTFC-01 binding, uptake, and internalization were conducted in SSTR2-transfected U2OS cells. Ex-vivo biodistribution and fluorescence imaging were performed in H69-tumor bearing mice. Results eTFC-01 demonstrated a two-fold higher IC50 value for SSTR2 compared to the gold standard DOTA-TATE. Labeling of eTFC-01 with [111In]InCl3 gave a high radiochemical yield and purity. The uptake of [111In]In-eTFC-01 in U2OS.SSTR2 cells was two-fold lower than the uptake of [111In]In-DOTA-TATE, consistent with the binding affinity. Tumor uptake in H69-xenografted mice was lower for [111In]In-eTFC-01 at all-time points compared to [111In]In-DOTA-TATE. Prolonged blood circulation led to increased accumulation of [111In]In-eTFC-01 in highly vascularized tissues, such as lungs, skin, and heart. Fluorescence measurements in different organs correlated with the radioactive signal distribution. Conclusion The successful synthesis and coupling of the trifunctional chelate to the peptide and fluorescent dye support the potential of this synthetic approach to generate dual labeled tracers. While promising in vitro, the in vivo results obtained with [111In]In-eTFC-01 suggest the need for adjustments to enhance tracer distribution.

Introduction. Initially discovered as a mechanism to protect host neutrophils from pathogens and prevent spread of infection outside inflammatory site, neutrophil extracellular traps (NETs) have been implicated in progression of other diseases associated with sterile inflammation such as autoimmune diseases, diabetes, and cancer. NETs components (myeloperoxidase, citrullinated histones, cell-free DNA) exhibit manifold effects on tumor cells, thereby emphasizing a need to be aware of the features of biological functions related to their constituents and their place in carcinogenesis to identify major molecular targets for targeted therapy of gynecologic cancers in the future.Aim: to determine an impact of NETs on tumor progression/metastasis and thrombosis risk in gynecologic cancer.Materials and Methods. A single-center interventional study was conducted: 70 women with uterine, ovarian and cervical cancer were examined; 60 age-matched apparently healthy women without thrombotic complications were selected as controls. All study participants were examined for myeloperoxidase (MРO), citrullinated histone (сitH3), proinflammatory cytokine interleukin-1β (IL-1β), and neutrophil/lymphocyte ratio (NLR).Results. Laboratory biomarkers such as MPO (p < 0.001), IL-1β (p < 0.001) and NLR (p = 0.003) were significantly more often elevated in patients with oncological pathology compared to group of healthy women. 32 (45.7 %) of the 70 women with cancer of the reproductive system had metastases. Metastases-related analysis in patients showed significant differences in MPO level (p = 0.002), but not in level of citH3, IL-1β and NLR (p = 0.441, p = 0.159, and p = 0.739, respectively). Elevated citH3 vs. MPO, IL-1β and NLR level was significantly more often associated with developing thrombosis in study patients (p < 0.001).Conclusion. The results of our study demonstrate that inflammation and NETs components such as MPO and citH3 may be potentially implicated in many aspects of carcinogenesis including tumor metastasis and the risk of developing thrombosis in cancer patients.

Abstract Introduction This study assesses the accuracy of neutrophil activation markers, including neutrophil extracellular traps (NETs) and calprotectin, as biomarkers of disease activity in patients with established rheumatoid arthritis (RA). We also analyse the relationship between NETs and various types of therapies as well as their association with autoimmunity. Methods Observational cross-sectional study of patients with RA receiving treatment with biological disease-modifying antirheumatic drugs or Janus kinase inhibitors (JAK-inhibitors) for at least 3 months. Plasma calprotectin levels were measured using an enzyme-linked immunosorbent assay test kit and NETs by measuring their remnants in plasma (neutrophil elastase-DNA and histone-DNA complexes). We also assessed clinical disease activity, joint ultrasound findings and autoantibody status [reumatoid factor (RF), anti-citrullinated peptide/protein antibodies (ACPAs) and anti-carbamylated protein (anti-CarP)]. Associations between neutrophilic biomarkers and clinical or ultrasound scores were sought using correlation analysis. The discriminatory capacity of both neutrophilic biomarkers to detect ultrasound synovitis was analysed through receiver-operating characteristic (ROC) curves. Results One hundred fourteen patients were included. Two control groups were included to compare NET levels. The active control group consisted of 15 patients. The second control group consisted of 30 healthy subjects. Plasma NET levels did not correlate with clinical disease status, regardless of the clinic index analysed or the biological therapy administered. No significant correlation was observed between NET remnants and ultrasound synovitis. There was no correlation between plasma NET and autoantibodies. In contrast, plasma calprotectin positively correlated with clinical parameters (swollen joint count [SJC] rho = 0.49; P 0.50; P

Abstract Hundreds of thousands of polymorphonuclear neutrophils (PMNs) are collected from the ocular surface upon waking, while few are harvested during daytime. This study aimed to investigate potential factors contributing to the circadian infiltration of tear PMNs, including changes in IL-8 and C5a in tears, and their phenotypes across different time points in a 24-h cycle. Tear PMNs were collected using a gentle eyewash after 2-h and 7-h of sleep (eye closure, EC) at night, after 2-h EC during the day, and towards the end of the afternoon. Significantly fewer cells were collected after 2-h EC during the day compared to 2-h EC at night. A positive correlation between IL-8 and PMN numbers existed, but not with C5a. Tear PMNs collected after 2-h EC at night were less degranulated and possessed a larger activation potential compared to 7-h EC. Tear PMNs from 7-h EC at night exhibited hyper-segmented nuclei and more NETosis compared to 2 h EC night, indicating an aged and activated phenotype. The diurnal-nocturnal recruitment pattern of tear PMNs may be driven by increased IL-8 in nighttime tears. Higher degranulation and NETs point to the significant activation of tear PMNs on the ocular surface during prolonged eye closure at night.

INTRODUCTION: Ischemia-reperfusion injury (IRI) involves a positive amplification feedback loop that stimulates innate immune-driven tissue damage associated with organ procurement from deceased donors and during transplantation surgery. As our appreciation of its basic immune mechanisms has improved in recent years, translating putative biomarkers into therapeutic interventions in clinical transplantation remains challenging. AREAS COVERED: This review presents advances in translational/clinical studies targeting immune responses to reactive oxygen species in IRI-stressed solid organ transplants, especially livers. Here we focus on novel concepts to rejuvenate suboptimal donor organs and improve transplant function using pharmacologic and machine perfusion (MP) strategies. Cellular damage induced by cold ischemia/warm reperfusion and the latest mechanistic insights into the microenvironments role that leads to reperfusion-induced sterile inflammation is critically discussed. EXPERT OPINION: Efforts to improve clinical outcomes and increase the donor organ pool will depend on improving donor management and our better appreciation of the complex mechanisms encompassing organ IRI that govern the innate-adaptive immune interface triggered in the peritransplant period and subsequent allo-Ag challenge. Computational techniques and deep machine learning incorporating the vast cellular and molecular mechanisms will predict which peri-transplant signals and immune interactions are essential for improving access to the long-term function of life-saving transplants.

Background: Integrating radioactive and optical imaging techniques can facilitate the prognosis and surgical guidance for cancer patients. Using a single dual-labeled tracer ensures consistency in both imaging modalities. However, developing such molecule is challenging due to the need to preserve the biochemical properties of the tracer while introducing bulky labeling moieties. In our study, we designed a trifunctional chelate that facilitates the coupling of the targeting vector and fluorescent dye at opposite sites to avoid undesired steric hindrance effects. The synthesis of the trifunctional chelate N3-Py-DOTAGA-(tBu)3 (7) involved a five-step synthetic route, followed by conjugation to the linear peptidyl-resin 8 through solid-phase synthesis. After deprotection and cyclization, the near-infrared fluorescent dye sulfo-Cy.5 was introduced using copper free click chemistry, resulting in eTFC-01. Subsequently, eTFC-01 was labeled with [111In]InCl3. In vitro assessments of eTFC-01 binding, uptake, and internalization were conducted in SSTR2-transfected U2OS cells. Ex-vivo biodistribution and fluorescence imaging were performed in H69-tumor bearing mice. Results: eTFC-01 demonstrated a two-fold higher IC50 value for SSTR2 compared to the gold standard DOTA-TATE. Labeling of eTFC-01 with [111In]InCl3 gave a high radiochemical yield and purity. The uptake of [111In]In-eTFC-01 in U2OS.SSTR2 cells was two-fold lower than the uptake of [111In]In-DOTA-TATE, consistent with the binding affinity. Tumor uptake in H69-xenografted mice was lower for [111In]In-eTFC-01 at all-time points compared to [111In]In-DOTA-TATE. Prolonged blood circulation led to increased accumulation of [111In]In-eTFC-01 in highly vascularized tissues, such as lungs, skin, and heart. Fluorescence measurements in different organs correlated with the radioactive signal distribution. Conclusion: The successful synthesis and coupling of the trifunctional chelate to the peptide and fluorescent dye support the potential of this synthetic approach to generate dual labeled tracers. While promising in vitro, the in vivo results obtained with [111In]In-eTFC-01 suggest the need for adjustments to enhance tracer distribution. [ABSTRACT FROM AUTHOR]

Despite neutrophil involvement in inflammation and tissue repair, little is understood about their inflammatory status in acute coronary syndrome (ACS) patients with poor outcomes. Hence, we investigated the potential correlation between neutrophil inflammatory markers and the prognosis of ACS patients with/without diabetes and explored whether neutrophils demonstrate a unique inflammatory phenotype in patients experiencing an adverse in-hospital outcome. The study enrolled 229 ACS patients with or without diabetes. Poor evolution was defined as either death, left ventricular ejection fraction (LVEF) <40%, Killip Class 3/4, ventricular arrhythmias, or mechanical complications. Univariate and multivariate analyses were employed to identify clinical and paraclinical factors associated with in-hospital outcomes. Neutrophils isolated from fresh blood were investigated using qPCR, Western blot, enzymatic assay, and immunofluorescence. Poor evolution post-myocardial infarction (MI) was associated with increased number, activity, and inflammatory status of neutrophils, as indicated by significant increase of Erythrocyte Sedimentation Rate (ESR), C-reactive protein (CRP), fibrinogen, interleukin-1β (IL-1β), and, interleukin-6 (IL-6). Among the patients with complicated evolution, neutrophil activity had an important prognosis value for diabetics. Neutrophils from patients with unfavorable evolution revealed a pro-inflammatory phenotype with increased expression of CCL3, IL-1β, interleukin-18 (IL-18), S100A9, intracellular cell adhesion molecule-1 (ICAM-1), matrix metalloprotease (MMP-9), of molecules essential in reactive oxygen species (ROS) production p22phox and Nox2, and increased capacity to form neutrophil extracellular traps. Inflammation is associated with adverse short-term prognosis in acute ACS, and inflammatory biomarkers exhibit greater specificity in predicting short-term outcomes in diabetics. Moreover, neutrophils from patients with unfavorable evolution exhibit distinct inflammatory patterns, suggesting that alterations in the innate immune response in this subgroup may exert detrimental effects on disease progression. [ABSTRACT FROM AUTHOR]

Neutrophils, which constitute the most abundant leukocytes in human blood, emerge as crucial players in the induction of endothelial cell death and the modulation of endothelial cell responses under both physiological and pathological conditions. The hallmark of preeclampsia is endothelial dysfunction induced by systemic inflammation, in which neutrophils, particularly through the formation of neutrophil extracellular traps (NETs), play a pivotal role in the development and perpetuation of endothelial dysfunction and the hypertensive state. Considering the potential of numerous pharmaceutical agents to attenuate NET formation (NETosis) in preeclampsia, a comprehensive assessment of the extensively studied candidates becomes imperative. This review aims to identify mechanisms associated with the induction and negative regulation of NETs in the context of preeclampsia. We discuss potential drugs to modulate NETosis, such as NF-κβ inhibitors, vitamin D, and aspirin, and their association with mutagenicity and genotoxicity. Strong evidence supports the notion that molecules involved in the activation of NETs could serve as promising targets for the treatment of preeclampsia. [ABSTRACT FROM AUTHOR]

Background: The formation of gallstones is often accompanied by chronic inflammation, and the mechanisms underlying inflammation and stone formation are not fully understood. Our aim is to utilize single‐cell transcriptomics, bulk transcriptomics, and microbiome data to explore key pathogenic bacteria that may contribute to chronic inflammation and gallstone formation, as well as their associated mechanisms. Methods: scRNA‐seq data from a gallstone mouse model were extracted from the Gene Expression Omnibus (GEO) database and analyzed using the FindCluster() package for cell clustering analysis. Bulk transcriptomics data from patients with gallstone were also extracted from the GEO database, and intergroup functional differences were assessed using GO and KEGG enrichment analysis. Additionally, 16S rRNA sequencing was performed on gallbladder mucosal samples from asymptomatic patients with gallstone (n = 6) and liver transplant donor gallbladder mucosal samples (n = 6) to identify key bacteria associated with stone formation and chronic inflammation. Animal models were constructed to investigate the mechanisms by which these key pathogenic bacterial genera promote gallstone formation. Results: Analysis of scRNA‐seq data from the gallstone mouse model (GSE179524) revealed seven distinct cell clusters, with a significant increase in neutrophil numbers in the gallstone group. Analysis of bulk transcriptomics data from patients with gallstone (GSE202479) identified chronic inflammation in the gallbladder, potentially associated with dysbiosis of the gallbladder microbiota. 16S rRNA sequencing identified Helicobacter pylori as a key bacterium associated with gallbladder chronic inflammation and stone formation. Conclusions: Dysbiosis of the gallbladder mucosal microbiota is implicated in gallstone disease and leads to chronic inflammation. This study identified H. pylori as a potential key mucosal resident bacterium contributing to gallstone formation and discovered its key pathogenic factor CagA, which causes damage to the gallbladder mucosal barrier. These findings provide important clues for the prevention and treatment of gallstones. [ABSTRACT FROM AUTHOR]

Neutrophil extracellular traps (NETs) are induced in the innate immune response against infectious agents and are also implicated in the pathogenesis of various cancers and autoimmune diseases. Peptidylarginine deiminase 4 (PAD4), an enzyme that converts arginine to citrulline, is also involved in NET formation. In this study, we investigated the pathogenic effect of PAD4 on NETs in inflammatory bowel disease using a trinitrobenzene sulfonic acid (TNBS)-induced murine colitis model. PAD4-deficient (PAD4KO) mice were generated by CRISPR-Cas9-mediated genomic editing. NETs were triggered in peritoneal neutrophils obtained from wild-type mice by A23187 (a calcium ionophore), but these responses were completely abolished in the PAD4KO mice. Experimental colitis was induced in wild-type and PAD4KO mice via an intrarectal injection of TNBS. TNBS injection resulted in body weight loss, extensive colonic erosion, and ulceration in wildtype mice. However, these responses were significantly attenuated following the administration of Cl-amidine (an inhibitor of pan-PADs) and DNase I (an inhibitor of NET formation), in combination with PAD4KO in mice. TNBS-induced increases in myeloperoxidase activity, inflammatory cytokine expression, and NET formation in the colon were significantly reduced following the administration of Cl-amidine, DNase I injection, and PAD4KO. These findings suggest that NET formation contributes to the pathogenesis of TNBS-induced colitis via PAD4. Thus, PAD4 is a promising target for the treatment of inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Background: Vitamin C is a potent scavenger of reactive oxygen species, which induce neutrophil extracellular trap (NET) formation. NETs are a major source of autoantigens and are involved in systemic lupus erythematosus (SLE) pathogenesis. We determined vitamin C status and evaluated NET formation and inflammatory cytokines in children with lupus nephritis. Methods: Serum vitamin C was measured in 46 patients (82.6% females, mean age 14.5 ± 0.3 years). Vitamin C levels < 0.3 mg/dL indicated vitamin C deficiency. Patients were divided into two groups according to serum vitamin C levels: normal and low (< 0.3 mg/dL). We compared NET formation and levels of SLE-related cytokines, including interleukin (IL)-8, IL-10, and tumor necrosis factor-α (TNF-α), between groups. NET formation was determined through measurement of serum citrullinated histone 3 levels and mRNA expression of peptidyl arginine deiminase-4 and assessment of the percentage of neutrophils with NETs by immunofluorescence. Results: Nine patients (19.6%) had vitamin C deficiency. Kidney pathology assessment at disease onset revealed that histological activity index and number of kidney biopsies containing crescentic glomeruli were higher in vitamin C-deficient patients, but chronicity index was not. NET formation and serum IL-8 were more prominent in vitamin C-deficient patients. Serum IL-8 levels were 12.9 ± 5.2 pg/mL in low vitamin C group and 5.2 ± 0.9 pg/mL in normal vitamin C group (p = 0.03). Serum IL-10 and TNF-α were similar between groups. Conclusions: Our study demonstrated correlation among vitamin C deficiency, increased NET formation, and IL-8 upregulation in children with lupus nephritis. A prospective study is required to evaluate cause‒effect relationships of vitamin C status, NET formation and IL-8 expression. [ABSTRACT FROM AUTHOR]

As a disease causing a global pandemic, the progression of symptoms to severe disease in patients with COVID-19 often has adverse outcomes, but research on the immunopathology of COVID-19 severe disease remains limited. In this study, we used mRNA-seq data from the peripheral blood of COVID-19 patients to identify six COVID-19 severe immune characteristic genes (FPR1, FCGR2A, TLR4, S100A12, CXCL1, and L TF), and found neutrophils to be the critical immune cells in COVID-19 severe disease. Subsequently, using scRNA-seq data from bronchoalveolar lavage fluid from COVID-19 patients, neutrophil subtypes highly expressing the S100A family were found to be located at the end of cellular differentiation and tended to release neutrophil extracellular traps. Finally, it was also found that alveolar macrophages, macrophages, and monocytes with a high expression of COVID-19 severe disease immune characteristic genes may influence neutrophils through intercellular ligand–receptor pairs to promote neutrophil extracellular trap release. This study provides immune characteristic genes, critical immune pathways, and immune cells in COVID-19 severe disease, explores intracellular immune transitions of critical immune cells and pit-induced intercellular communication of immune transitions, and provides new biomarkers and potential drug targets for the treatment of patients with COVID-19 severe disease. [ABSTRACT FROM AUTHOR]

Purpose of Review: In this review, we summarize the current evidence that suggests that neutrophils play a key role in facilitating damage to local bone structures. Recent Findings: Neutrophil infiltration is a hallmark of inflammatory bone diseases such as rheumatoid arthritis (RA) and periodontitis disease (PD). Both of these human diseases are marked by an imbalance in bone homeostasis, favoring the degradation of local bone which ultimately leads to erosions. Osteoclasts, a multinucleated resident bone cell, are responsible for facilitating the turnover of bone and the bone damage observed in these diseases. The involvement of neutrophils and neutrophil extracellular trap formation have recently been implicated in exacerbating osteoclast function through direct and indirect mechanisms. We highlight a recent finding that NET proteins such as histones and elastase can generate non-canonical, inflammatory osteoclasts, and this process is mediated by post-translational modifications such as citrullination and carbamylation, both of which act as autoantigens in RA. Summary: It appears that NETs, autoantibodies, modified proteins, cytokines, and osteoclasts all ultimately contribute to local and permanent bone damage in RA and PD. However, more studies are needed to fully understand the role of neutrophils in inflammatory bone diseases. [ABSTRACT FROM AUTHOR]

Neutrophil extracellular traps (NETs) have been identified as triggers for a self‐limited inflammatory reaction upon contact with nanoparticles within our bodies. This typically results in entrapping potentially harmful nano‐ or micro‐objects following an immune burst. The demand for potent adjuvants has led to research on particulate‐based adjuvants, particularly those that act via NET formation. Various particles, including hydrophobic nanoparticles, needle‐like microparticles, and other natural and artificial crystals, have been shown to induce NET formation, eliciting a robust humoral and cellular immune response toward co‐injected antigens. The NET formation was found to be the basis of the efficient use of alum as a vaccine adjuvant. Thus, nanoparticles with specific surface properties serve as NET‐stimulating adjuvants. In this mini‐review, we aim to summarize the current knowledge about the surface properties of particulate objects and the molecular pathways involved in inducing NET formation by neutrophils. Additionally, we discuss the potential use of nanoparticles for activating neutrophils in the tissues and the exploitation of such activation for enhancing vaccine adjuvants. [ABSTRACT FROM AUTHOR]

Introduction: NETosis, the mechanism by which neutrophils release extracellular traps (NETs), is closely related to inflammation. During the allogeneic hematopoietic stem cell transplantation (allo-HSCT), different stimuli can induce NETs formation. Inflammation and endothelial injury have been associated with acute graft-versus-host disease (aGVHD) and complications after allo-HSCT. We focus on the study of NETosis and its relation with cytokines, hematological and biochemical parameters and clinical outcomes before, during and after allo-HSCT. Methods: We evaluate the capacity of plasma samples from allo-HSCT patients to induce NETosis, in a cell culture model. Plasma samples from patients undergoing allo-HSCT had a stronger higher NETs induction capacity (NETsIC) than plasma from healthy donors throughout the transplantation process. An optimal cut-off value by ROC analysis was established to discriminate between patients whose plasma triggered NETosis (NETs+IC group) and those who did not (NETs-IC group). Results: Prior to conditioning treatment, the capacity of plasma samples to trigger NETosis was significantly correlated with the Endothelial Activation and Stress Index (EASIX) score. At day 5 after transplant, patients with a positive NETsIC had higher interleukin (IL)-6 and C-reactive protein (CRP) levels and also a higher Modified EASIX score (M-EASIX) than patients with a negative NETsIC. EASIX and M-EASIX scores seek to determine inflammation and endothelium damage, therefore it could indicate a heightened immune response and inflammation in the group of patients with a positive NETsIC. Cytokine levels, specifically IL-8 and IL-6, significantly increased after allo-HSCT with peak levels reached on day 10 after graft infusion. Only, IL-10 and IL-6 levels were significantly higher in patients with a positive NETsIC. In our small cohort, higher IL-6 and IL-8 levels were related to early severe complications (before day 15 after transplant). Discussion: Although early complications were not related to NETosis by itself, NETosis could predict overall non-specific but clinically significant complications during the full patient admission. In summary, NETosis can be directly induced by plasma from allo-HSCT patients and NETsIC was associated with clinical indicators of disease severity, cytokines levels and inflammatory markers. [ABSTRACT FROM AUTHOR]

Growing evidence supports the suggestion that the peripheral immune system plays a role in different pathologies associated with cognitive impairment, such as vascular dementia (VD) or Alzheimer's disease (AD). The aim of this review is to summarize, within the peripheral immune system, the implications of different types of myeloid cells in AD and VD, with a special focus on post‐stroke cognitive impairment and dementia (PSCID). We will review the contributions of the myeloid lineage, from peripheral cells (neutrophils, platelets, monocytes and monocyte‐derived macrophages) to central nervous system (CNS)‐associated cells (perivascular macrophages and microglia). Finally, we will evaluate different potential strategies for pharmacological modulation of pathological processes mediated by myeloid cell subsets, with an emphasis on neutrophils, their interaction with platelets and the process of immunothrombosis that triggers neutrophil‐dependent capillary stall and hypoperfusion, as possible effector mechanisms that may pave the way to novel therapeutic avenues to stop dementia, the epidemic of our time. LINKED ARTICLES: This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc [ABSTRACT FROM AUTHOR]