Search Results (772)

Myocardial ischemia–reperfusion injury (MIRI) represents a major contributor to morbidity and mortality in patients undergoing reperfusion therapy after acute myocardial infarction. Although timely restoration of coronary blood flow is essential for myocardial salvage, reperfusion paradoxically initiates a complex cascade of molecular and cellular events that may aggravate myocardial injury. Oxidative stress is considered one of the central mechanisms underlying MIRI, primarily through excessive production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), leading to mitochondrial dysfunction, calcium overload, endothelial injury, inflammatory activation, and cardiomyocyte death. This review summarizes the current understanding of the pathophysiological mechanisms involved in oxidative stress-mediated reperfusion injury, with emphasis on mitochondrial permeability transition pore opening, inflammasome activation, cytokine release, neutrophil extracellular trap formation, macrophage polarization, and interconnected cell death pathways including PANoptosis. Emerging evidence regarding immunometabolic regulation and epigenetic modulation in MIRI is also discussed. In addition, current pharmacological and non-pharmacological cardioprotective strategies targeting oxidative stress, mitochondrial dysfunction, and inflammatory signaling are reviewed, highlighting both promising experimental findings and the persistent challenges in clinical translation. A deeper understanding of the molecular interplay between oxidative stress and inflammatory pathways may facilitate the development of integrated therapeutic approaches aimed at improving myocardial recovery and long-term cardiovascular outcomes following reperfusion therapy. Full article

Colorectal cancer (CRC) is a leading cause of cancer death worldwide, mainly due to metastasis. Circulating tumor cells (CTCs) act as the biological “seeds” of dissemination, traveling through the bloodstream to colonize distant organs. However, the blood is a hostile environment where CTCs must constantly face immune pressure. This review explores the bidirectional interactions between CTCs and immune cells in CRC, asking whether CTCs are merely vulnerable targets of immunosurveillance or can exploit the immune system for survival and metastasis. We dissect intrinsic and extrinsic immune evasion mechanisms, including MHC-I modulation, immune checkpoint expression (PD-L1, CD47, FasL), platelet cloaking, and neutrophil extracellular traps (NETs). Furthermore, we examine how CTCs form heterotypic clusters with monocytes, neutrophils, and lymphocytes, creating pro-metastatic niches and promoting phenotypic plasticity. The impact of CTCs on systemic immunity, including reprogramming of NK cells, T lymphocytes, and myeloid-derived suppressor cells (MDSCs), is discussed. Importantly, we highlight the emerging role of CTCs as dynamic biomarkers for immunotherapy, focusing on the predictive value of PD-L1+ CTCs and the potential of CTC-derived neoantigens for personalized vaccination. Despite progress, challenges remain in standardization, detection sensitivity, and clinical validation. Understanding the equilibrium between immune elimination and evasion by CTCs is crucial to develop novel interventions that interrupt the metastatic dialog and improve outcomes for CRC patients. Full article

Neutrophil extracellular traps (NETs) are web-like structures composed of decondensed DNA, histones, and proteins released by activated neutrophils. Originally identified as an innate defense mechanism against pathogens, NETs have since been implicated in cancer progression and immune evasion. Within the tumor microenvironment (TME), NETs suppress anti-tumor immunity through multiple mechanisms, including the physical exclusion of CD8⁺ cytotoxic T lymphocytes from the tumor interior and upregulation of exhaustion markers via checkpoint ligands. This review synthesizes current preclinical and clinical evidence on the interplay between NETs and CD8⁺ T cells across multiple malignancies, including non-small cell lung cancer, pancreatic ductal adenocarcinoma, cholangiocarcinoma, colorectal cancer, bladder cancer, hepatocellular carcinoma, skin cancer, and penile cancer. Cancer-specific mechanisms of NET-mediated immune suppression are discussed, including IL-8, IL-17, CXCL6, and TGF-β-driven NETosis pathways. Clinical data consistently demonstrate that elevated NET levels correlate with reduced CD8⁺ T cell infiltration, T cell dysfunction, and worse patient outcomes. Emerging therapeutic strategies targeting this axis are reviewed, including DNase I-mediated NET degradation, Peptidyl arginine deiminase 4 (PAD4) inhibition, CXCR2 blockade, and combination approaches with immune checkpoint inhibitors. These interventions have shown promise in restoring CD8⁺ T cell cytotoxicity and overcoming immunotherapy resistance in preclinical models. Collectively, the evidence supports the NET-CD8⁺ T cell axis as a promising prognostic and therapeutic target warranting further clinical investigation. Full article

In hemodialysis patients, Body Mass Index is insufficient in assessing their nutritional status due to the ‘obesity paradox’ and the association between body composition and inflammation. This study assessed the relationship between body composition, traditional inflammatory markers, the new NETosis indicators (neutrophil extracellular traps), and their association with 12-month mortality. The study included 99 maintenance hemodialysis (HD) patients. Their body composition was assessed using bioelectrical impedance analysis. Blood serum was tested for inflammatory markers (hs-CRP-high sensitive c-reactive protein, IL-6 interleukin-6, TNF-α tumor necrosis factor alfa, IL-1β interleukin-1 beta), NETosis markers (citrullinated histone CH3, myeloperoxidase -MPO, elastase), and nutritional status parameters (albumin, transferrin). No correlation between BMI -body mas index and inflammation was demonstrated. Higher adipose tissue, particularly visceral, was significantly positively correlated with IL-6 and hs-CRP levels, while muscle mass was negatively correlated with inflammation. Dialysis catheter use was associated with higher CH3 levels (NETosis indicator) and lower albumin concentrations. Low albumin levels and high TNF-α levels were independent predictors of death. Body composition, rather than BMI, is associated with the severity of inflammation. Visceral obesity is positively correlated with increased inflammation, while muscle mass shows an inverse association. Dialysis catheters are linked to higher NETosis markers and lower albumin levels, which are associated with a poorer prognosis. Full article

Background/Objectives: Myocardial microcirculatory dysfunction is a critical pathological feature of cardiovascular diseases, closely associated with inflammation, oxidative stress, and excessive neutrophil activation. Neutrophil extracellular traps (NETs) serve as crucial mediators of myocardial microvascular inflammatory injury. Dalbergia odorifera volatile oil (DOVO) demonstrates anti-inflammatory and antioxidant properties; however, its protective role against myocardial microcirculatory damage and its regulatory effect on NET formation remain inadequately characterized. This study investigates the protective effects of DOVO on myocardial microcirculatory disturbances and elucidates the underlying mechanisms related to NETs. Methods: A rat model of myocardial microcirculatory dysfunction was established through polyethylene microsphere injection, and an in vitro neutrophil inflammation model was generated using differentiated HL-60 cells. DOVO was administered at various doses both in vivo and in vitro, and hemodynamics, inflammatory cytokines, oxidative stress, and NET-related markers, including MPO and CitH3, were analyzed. Results: DOVO dose-dependently ameliorated microcirculatory impairment, hemodynamic disorders, inflammation, and oxidative stress in rats, significantly suppressing NET formation. In differentiated HL-60 cells, DOVO similarly reduced inflammatory gene expression and inhibited LPS-induced NETs production by downregulating MPO and CitH3. Conclusions: DOVO suggests a protective effect against myocardial microcirculatory injury by inhibiting oxidative stress, inflammatory responses, and subsequent NET formation. These findings elucidate a novel mechanism by which DOVO alleviates microcirculation-related cardiac damage and provide a theoretical basis for its application in cardiovascular injury. Full article

Polymer coatings are integral to nearly every modern cardiovascular and endovascular device, including drug-eluting stents (DESs) and drug-coated balloons (DCBs), bioabsorbable vascular scaffolds (BVSs), occluders, grafts, and catheter and guidewire hydrophilic surfaces. Persistent complications, including late stent thrombosis, delayed endothelialization, hypersensitivity, and restenosis, show that coatings actively shape biological responses rather than acting as inert drug carriers. Their surface chemistry, drug release kinetics, and degradation behavior are upstream determinants of blood– and tissue–material responses that govern healing and failure. This review frames coating selection as a structure–property–biological response problem. It surveys the major classes of synthetic polymer coatings and the defining surface and bulk properties. This review also examines how composition and architecture control drug release, and traces the interfacial cascade of protein adsorption, coagulation and complement activation, platelet and leukocyte responses, and neutrophil extracellular trap (NET) formation. These mechanisms are linked to contemporary design strategies that improve hemocompatibility, limit thrombosis, promote endothelial recovery, and tune degradation, and to the standardization and translation gaps that remain. The central message is that polymer coatings are not biologically equivalent. Their surface chemistries and degradation profiles determine the thrombo-inflammatory outcomes. Therefore, coating design should be guided by intended biological response, not drug release alone. Full article

Gastrointestinal symptoms (GI) (abdominal pain, vomiting, and diarrhea) during the febrile phase of dengue (less than 5 days from fever onset) might indicate prominent innate immune responses. Serum and feces samples from cases with GI symptoms versus those without GI symptoms (n = 20 per group) were analyzed. From these, only the neutrophil extracellular traps (NETs), serum fibroblast growth factor (FGF) 21, and fecal microbiome analyses, but not the routine parameters, endotoxemia, or serum cytokines, were higher in the GI cases than in the non-GI cases. From the in vitro experiments, both lipopolysaccharide (LPS) and the dengue virus (DENV) upregulated the FGF receptor 1 (FGFR1) and cytokines in hepatocytes (HepG2) and THP-1-differentiated macrophages. Meanwhile, LPS and DENV induced NETs in isolated neutrophils from healthy volunteers. Only the starvation protocol, but not LPS or DENV, enhanced supernatant FGF-21 from hepatocytes. Incubation of recombinant FGF-21 in LPS + DENV-activated cells (hepatocytes, macrophages, and neutrophils) attenuated inflammation, as determined by supernatant cytokines and NETs. Hence, abdominal symptoms in dengue during the febrile phase indicate prominent innate immune responses, as detected by NETs and FGF-21 (an acute-phase protein), implying significant hepatic stress with a possible counteracting anti-inflammation. Full article

Dental calculus is a highly prevalent oral condition in dogs and is widely recognized as an important risk factor for gingival inflammation and periodontal disease. Effective strategies for its prevention and treatment remain limited, highlighting the significance of exploring novel mechanisms underlying its formation. Neutrophil extracellular traps (NETs), a key component of innate immunity, have been found in various diseases. To investigate the relationship between NETs and canine dental calculus formation, NET-associated markers were assessed in the oral cavities of dogs with dental calculus and healthy controls. Based on previously published full-length 16S rRNA amplicon sequencing data of canine dental calculus, Porphyromonas gulae was selected as a candidate NET-inducing bacterium for subsequent validation experiments. Subsequent neutrophil stimulation experiments were conducted to explore the effects of NETs and related factors on dental calculus formation. Collectively, our findings demonstrate the presence of NETs within canine dental calculus and reveal that P. gulae present in canine dental calculus is capable of inducing NET formation. The level of myeloperoxidase–DNA complex in gingival crevicular fluid was significantly elevated in dogs with dental calculus. NETs promoted aggregation and microcrystal formation from calcium and phosphate ions under both physiological and supersaturated concentrations. By adhering to the surface of dental calculus, NETs facilitated calculus accumulation. This effect showed positive correlation with neutrophil counts and administration frequency, but was independent of the concentration of administered calcium and phosphate solutions. IL-1β promoted the formation of aggregated NETs but did not enhance calculus accumulation. DNase I inhibited this process by degrading NET-DNA. In conclusion, dental calculus and the calculus-inhabiting P. gulae could stimulate oral neutrophils to release NETs, which participate in and facilitate the initial formation, aggregation, and subsequent accumulation of canine dental calculus. Full article

Cervical cancer is a common gynecological malignancy, with a 5-year survival rate of only 17% for recurrent or metastatic cases. Increased extracellular matrix stiffness, a key change in the tumor mechanical microenvironment, promotes tumor metastasis via mechanotransduction. Piezo1, a mechanosensitive cation channel, senses matrix stiffness and converts mechanical signals into intracellular chemical signals. Neutrophil extracellular traps (NETs) are overformed in tumors, but the mechanism by which matrix stiffness regulates NETs in cervical cancer remains unclear. We detected matrix stiffness and related protein expression in cervical cancer tissues using atomic force microscopy and histochemical staining. Polyacrylamide gel models were used to culture HeLa/SiHa cells, with transcriptome sequencing and ELISA to analyze IL-8 expression. NETs were induced from human peripheral blood neutrophils, and their effect on lymphatic endothelial cells was evaluated. A TC-1 mouse model was used to verify in vivo effects, and Western blot/ELISA explored the Piezo1/NF-κB pathway. Higher Young’s modulus, increased α-SMA/Collagen I expression and collagen content in metastatic cervical cancer tissues. High matrix stiffness activated Piezo1/NF-κB, upregulated IL-8, induced NETs, and enhanced lymphatic endothelial cell tube formation/migration. BAPN reduced tumor stiffness, inhibited metastasis, and decreased NETs in mice. Knocking down Piezo1 blocked NF-κB activation and IL-8 upregulation. High matrix stiffness activates Piezo1/NF-κB to promote IL-8 secretion and NETs formation, enhancing lymphangiogenesis and cervical cancer metastasis, providing a new target for advanced cervical cancer treatment. Full article

Cathepsin C (CTSC), also known as dipeptidyl peptidase I, is an upstream activator of serine protease networks that may promote metastatic progression through inflammatory amplification and microenvironmental remodeling. Increasing evidence suggests that CTSC contributes to cancer progression not simply as an overexpressed lysosomal protease, but as a context-dependent regulator of metastatic traits. This review summarizes the structure, maturation, and biological functions of CTSC, with emphasis on its protease-activating capacity and its links to tumor-associated inflammation. Current evidence connecting CTSC to epithelial–mesenchymal transition, extracellular matrix remodeling, neutrophil extracellular trap formation, and immune microenvironment reprogramming is then synthesized across hepatocellular carcinoma, renal cell carcinoma, breast cancer, colorectal cancer, non-small-cell lung cancer, and glioma. Available data most strongly support a pro-metastatic role for CTSC in breast cancer and colorectal cancer, whereas evidence in several other malignancies remains predominantly preclinical and mechanistically incomplete. Importantly, CTSC is better viewed as a targetable protease network hub than as a universal pan-cancer metastatic driver. The biomarker potential and therapeutic relevance of CTSC are also evaluated, with particular attention to the opportunities and limitations of current DPP-1/CTSC inhibitors and the need for tumor-specific translational strategies. Overall, CTSC represents a promising but still incompletely validated target in oncology, and future work should prioritize tissue-specific dependency, biomarker qualification, and rational combination approaches. Full article

Background: Neutrophils play a role in idiopathic inflammatory myopathies (IIMs), especially in vasculopathic manifestations. While neutrophil extracellular traps (NETs) and low-density granulocytes (LDGs) have been described, the functional relevance of other subsets—such as naïve neutrophils, reverse transendothelial migration neutrophils (rTEM), myeloid-derived suppressor cells (MDSCs), and regulatory neutrophils—and their association with vasculopathy remains unknown. Objective: We aimed to characterize the phenotypic and functional profile of neutrophil subsets and their association with vasculopathic manifestations in IIM, adjusting for disease activity. Methods: We conducted a cross-sectional, single-center study including 59 IIM patients diagnosed by muscle biopsy and fulfilling 2017 ACR/EULAR criteria. Flow cytometry was used to immunophenotype myeloid subsets, and functional assays assessed phagocytosis and respiratory burst. Patients were stratified by clinical activity and presence of vasculopathy. Results: Vasculopathic patients showed expansion of LDGs (p = 0.0092), granulocytic and monocytic MDSCs expressing Arginase-1 (p = 0.0078, p = 0.0003) and PD-L1 (p = 0.0258, p = 0.0087), and rTEM neutrophils (p = 0.0775). In contrast, they exhibited a reduction in naïve neutrophils (p = 0.0004), phagocytosis (p < 0.0001) and respiratory burst (p = 0.0006). Multivariate analysis identified naïve neutrophils and activated CD177⁺ neutrophils as independent predictors of vasculopathy. A positive correlation between activated and naïve neutrophils were observed in patients with vasculopathic features (r = 0.43; p < 0.05). Conclusions: IIM patients with vasculopathic features display a distinct immune profile characterized by an imbalance between proinflammatory and regulatory neutrophil subsets, alongside persistent functional impairment. Full article

Acute kidney injury (AKI) caused by ischemia–reperfusion injury (IRI) involves rapid activation of innate immune responses, in which myeloid-derived immune cells critically shape injury severity. Y-box binding protein 1 (YB-1) regulates pro-inflammatory gene expression intracellularly and can be secreted to function extracellularly, yet how these two compartments jointly influence early IRI pathology remains poorly understood. To dissect the roles of intracellular myeloid versus extracellular YB-1, we subjected myeloid-specific Ybx1 knockout, Ybx1^fl/fl × LysM^cre, mice and wild-type (WT) littermates to unilateral renal IRI following administration of either a neutralizing anti-YB-1 antibody or control IgG. Kidney injury, inflammation, immune cell recruitment, neutrophil extracellular trap (NET) formation, antibody localization, and Fcγ receptor expression were assessed by qRT-PCR, histology, immunostaining, Western blotting, and flow cytometry. Myeloid-specific knockout of Ybx1 markedly reduced renal inflammation, neutrophil infiltration, NET formation, and tubular injury. This protective phenotype was lost when extracellular YB-1 was simultaneously reduced: anti-YB-1 treatment in knockout mice restored pro-inflammatory cytokine expression, increased tubular damage markers such as NGAL and KIM-1, exacerbated neutrophil recruitment and NET formation, and led to luminar accumulation of YB-1/anti-YB-1 immune complexes in tubular cells. Mechanistically, Ybx1-deficient myeloid cells exhibited significantly reduced CD16 expression, pointing to impaired Fcγ receptor-mediated phagocytosis as the cause of defective immune complex clearance. In contrast, wild-type mice efficiently cleared extracellular YB-1 complexes and showed no injury aggravation upon antibody treatment. Our findings identify myeloid YB-1 as a central regulator of early inflammatory injury in renal IRI and reveal that its protective depletion becomes pathogenic when extracellular YB-1 is simultaneously neutralized, likely due to unmasked defects in immune complex clearance. Full article

Ischemic stroke elicits a rapid and sustained innate immune response that critically contributes to blood–brain barrier (BBB) breakdown and secondary neuronal injury. Among the cellular mediators involved, neutrophil extracellular traps (NETs) have emerged as potent effectors of neurovascular damage. However, the regulatory mechanisms governing NET formation and their prolonged impact on BBB integrity remain incompletely understood. Increasing evidence indicates that NET formation is an epigenetically regulated process, requiring chromatin remodeling, histone modifications, DNA methylation changes and non-coding RNA-mediated control within neutrophils under ischemic conditions. These epigenetic events license the extrusion of DNA–histone–enzyme complexes that directly injure endothelial cells, degrade tight junction proteins, activate innate immune signaling pathways and amplify neuroinflammatory cascades at the neurovascular unit. Moreover, NET-derived chromatin and associated mediators can induce transcriptional and epigenetic alterations in BBB cells, thereby sustaining barrier permeability and impairing vascular repair mechanisms. In this review, we synthesize current knowledge on the epigenetic regulation of NET formation and delineate how epigenetically regulated NETs function as key disruptors of BBB integrity in ischemic stroke. Understanding this NETosis–epigenetics–BBB axis may uncover novel therapeutic strategies aimed at preserving neurovascular integrity and limiting post-stroke brain injury. Full article

The link between neutrophil extracellular traps (NETs) and hepatocyte ferroptosis in liver ischemia–reperfusion injury (LIRI) is unclear. Adipose-derived mesenchymal stem cell exosomes (ADSCs-Exo) hold therapeutic potential for LIRI. This study employed miniature pigs to investigate the NETs’ role and ADSCs-Exo’s protection in LIRI. In vitro, established hepatocyte oxygen-glucose deprivation/reoxygenation (OGD/R) model and Transwell co-culture system with polymorphonuclear neutrophils (PMNs). In vivo, a laparoscopic minimally invasive LIRI model was constructed in miniature pigs, followed by ADSCs-Exo intervention. Results demonstrated that NETs exacerbate OGD/R-induced hepatocyte ferroptosis via myeloperoxidase. ADSCs-Exo inhibited NET formation via the NADPH/MAPK pathway, thereby mitigating ferroptosis, and ultimately improved liver histopathology and function. This study is the first to demonstrate in a large animal model that ADSCs-Exo alleviate LIRI by inhibiting NET formation via the NADPH/MAPK pathway, consequently attenuating hepatocyte ferroptosis. These findings provide novel insights into LIRI pathogenesis, support the translational potential of ADSCs-Exo as a cell-free therapeutic strategy, and highlight the value of the miniature pig model in liver research. Full article

Neutrophils are central executors of innate immunity. Yet murine models are inherently limited by low baseline neutrophil counts. NSG mice are among the most widely used models for xenotransplantation and studies on the humanized immune system. Although G-CSF is known to stimulate granulopoiesis, the dose- and schedule-dependent effects of intraperitoneal G-CSF administration have not been systematically characterized in this immunodeficient background. Male NSG mice received intraperitoneal G-CSF according to one of five regimens (n = 6 per group): group 0 served as the saline control, group 1 received a single dose of 250 µg/kg G-CSF administered at 48 h; group 2 received a single dose of 250 µg/kg G-CSF administered at 24 h; group 3 received three doses of 250 µg/kg administered G-CSF at 0 h, 24 h, and 48 h and group 4 received a single dose of 500 µg/kg G-CSF administered at 48 h. All animals were sacrificed at 72 h. Circulating neutrophils were then quantified by flow cytometry, bone marrow neutrophil proportions by panoptic smear analysis, and splenic neutrophil abundance by Ly6G immunofluorescence. Systemic neutrophil activation was assessed via plasma neutrophil elastase (NE) activity and cell-free DNA (cfDNA) levels. Repeated G-CSF administration (Group 3) induced an approximately 13-fold expansion of circulating neutrophils, approaching the human physiological range, with significant increases also observed in bone marrow and a trend towards increased neutrophil abundance in the spleen. A single dose of 250 µg/kg administered at 24 h (group 2), produced significant neutrophil expansion in peripheral blood and bone marrow but not in the spleen, while all other single-dose regimens failed to induce significant expansion in any compartment. NE activity and cfDNA concentrations and a selected cytokine panel remained unaltered across all groups. This systematic comparison establishes repeated intraperitoneal G-CSF administration as a reproducible strategy to achieve human-like neutrophil levels in NSG mice without inducing systemic inflammation. This provides a validated protocol with direct utility in translational models of neutrophil-dependent diseases. Full article