Neutrophil extracellular traps mediate neuro-immunothrombosis

Neutrophil extracellular traps are primarily composed of DNA and histones and are released by neutrophils to promote inflammation and thrombosis when stimulated by various inflammato ry reactions.Neutrophil extracellular trap formation occurs through lytic and non-lytic pathways that can be further classified by formation mechanisms.Histones,von Willebrand factor,fibrin,and many other factors participate in the interplay between inflammation and thrombosis.Neuroimmunothrombosis summarizes the intricate interplay between inflammation and thrombosis during neural development and the pathogenesis of neurological diseases,providing cutting-edge insights into post-neurotrauma thrombotic events.The blood-brain barrier defends the brain and spinal cord against external assaults,and neutrophil extracellular trap involvement in blood-brain barrier disruption and immunothrombosis contributes substantially to secondary injuries in neurological diseases.Further research is needed to understand how neutrophil extracellular traps promote blood-brain barrier disruption and immunothrombosis,but recent studies have demonstrated that neutrophil extracellular traps play a crucial role in immunothrombosis,and identified modulators of neuro-immunothrombosis.However,these neurological diseases occur in blood vessels,and the mechanisms are unclear by which neutrophil extracellular traps penetrate the blood-brain barrier to participate in immunothrombosis in traumatic brain injury.This review discusses the role of neutrophil extracellular traps in neuro-immunothrombosis and explores potential therapeutic interventions to modulate neutrophil extracellular traps that may reduce immunothrombosis and improve traumatic brain injury outcomes.

Crossroads:Pathogenic role and therapeutic targets of neutrophil extracellular traps in rheumatoid arthritis

Rheumatoid arthritis(RA)is a prevalent autoimmune disease whose main features include chronic synovial inflammation,bone destruction,and joint degeneration.Neutrophils are often considered to be the first responders to inflammation and are a key presence in the inflammatory milieu of RA.Neutrophil extracellular traps(NETs),a meshwork of DNA-histone complexes and proteins released by activated neutrophils,are widely involved in the pathophysiology of autoimmune diseases,especially RA,in addition to playing a key role in the neutrophil innate immune response.NETs have been found to be an important source of citrullinated autoantigen antibodies and inflammatory factor release,which can activate RA synovial fibroblasts(FLS)and cause joint damage.This article reviews the role of NETs in the pathophysiology of RA,demonstrating the application of multiple molecules with various therapies,with a view to informing the discovery and development of novel biomarkers and therapeutic targets for RA.

Machine learning based on metabolomics unveils neutrophil extracellular trap-related metabolic signatures in non-small cell lung cancer patients undergoing chemoimmunotherapy

BACKGROUND Non-small cell lung cancer(NSCLC)is the primary form of lung cancer,and the combination of chemotherapy with immunotherapy offers promising treatment options for patients suffering from this disease.However,the emergence of drug resistance significantly limits the effectiveness of these therapeutic strategies.Consequently,it is imperative to devise methods for accurately detecting and evaluating the efficacy of these treatments.AIM To identify the metabolic signatures associated with neutrophil extracellular traps(NETs)and chemoimmunotherapy efficacy in NSCLC patients.METHODS In total,159 NSCLC patients undergoing first-line chemoimmunotherapy were enrolled.We first investigated the characteristics influencing clinical efficacy.Circulating levels of NETs and cytokines were measured by commercial kits.Liquid chromatography tandem mass spectrometry quantified plasma metabolites,and differential metabolites were identified.Least absolute shrinkage and selection operator,support vector machine-recursive feature elimination,and random forest algorithms were employed.By using plasma metabolic profiles and machine learning algorithms,predictive metabolic signatures were established.RESULTS First,the levels of circulating interleukin-8,neutrophil-to-lymphocyte ratio,and NETs were closely related to poor efficacy of first-line chemoimmunotherapy.Patients were classed into a low NET group or a high NET group.A total of 54 differential plasma metabolites were identified.These metabolites were primarily involved in arachidonic acid and purine metabolism.Three key metabolites were identified as crucial variables,including 8,9-epoxyeicosatrienoic acid,L-malate,and bis(monoacylglycerol)phosphate(18:1/16:0).Using metabolomic sequencing data and machine learning methods,key metabolic signatures were screened to predict NET level as well as chemoimmunotherapy efficacy.CONCLUSION The identified metabolic signatures may effectively distinguish NET levels and predict clinical benefit from chemoimmunotherapy in NSCLC patients.

Hypobaric Hypoxia Aggravates Renal Injury by Inducing the Formation of Neutrophil Extracellular Traps through the NF-κB Signaling Pathway

Objective The hypersensitivity of the kidney makes it susceptible to hypoxia injury.The involvement of neutrophil extracellular traps(NETs)in renal injury resulting from hypobaric hypoxia(HH)has not been reported.In this study,we aimed to investigate the expression of NETs in renal injury induced by HH and the possible underlying mechanism.Methods A total of 24 SD male rats were divided into three groups(n=8 each):normal control group,hypoxia group and hypoxia+pyrrolidine dithiocarbamate(PDTC)group.Rats in hypoxia group and hypoxia+PDTC group were placed in animal chambers with HH which was caused by simulating the altitude at 7000 meters(oxygen partial pressure about 6.9 kPa)for 7 days.PDTC was administered at a dose of 100 mg/kg intraperitoneally once daily for 7 days.Pathological changes of the rat renal tissues were observed under a light microscope;the levels of serum creatinine(SCr),blood urea nitrogen(BUN),cell-free DNA(cf-DNA)and reactive oxygen species(ROS)were measured;the expression levels of myeloperoxidase(MPO),citrullinated histone H3(cit-H3),B-cell lymphoma 2(Bcl-2),Bax,nuclear factor kappa B(NF-κB)p65 and phospho-NF-κB p65(p-NF-κB p65)in rat renal tissues were detected by qRT-qPCR and Western blotting;the localization of NF-κB p65 expression in rat renal tissues was observed by immunofluorescence staining and the expression changes of NETs in rat renal tissues were detected by multiplex fluorescence immunohistochemical staining.Results After hypoxia,the expression of NF-κB protein in renal tissues was significantly increased,the levels of SCr,BUN,cf-DNA and ROS in serum were significantly increased,the formation of NETs in renal tissues was significantly increased,and a large number of tubular dilatation and lymphocyte infiltration were observed in renal tissues.When PDTC was used to inhibit NF-κB activation,NETs formation in renal tissue was significantly decreased,the expression level of Bcl-2 in renal tissues was significantly increased,the expression level of Bax was significantly decreased,and renal injury was significantly alleviated.Conclusion HH induces the formation of NETs through the NF-κB signaling pathway,and it promotes apoptosis and aggravates renal injury by decreasing Bcl-2 and increasing Bax expression.

Blood neutrophil extracellular traps:a novel target for the assessment of mammary health in transition dairy cows

Background:Mammary health is important for transition dairy cows and has been well recognized to exert decisive effects on animal welfare.However,the factors influencing mammary health are still unclear.Differential somatic cell count(DSCC)could reflect the mastitis risk since it is the percentage of neutrophils plus lymphocytes in total somatic cells and could be reflective of mammary health of dairy cows.This work aimed to investigate the assessment and prognosis of the health of transition cows based on blood neutrophil extracellular traps(NETs).Results:Eighty-four transition Holstein dairy cows were selected.The serum was sampled in all the animals at week 1 pre-and postpartum,and milk was sampled at week 1 postpartum.Based on the DSCC in milk at week 1,cows with lower(7.4%±4.07%,n=15)and higher(83.3%±1.21%,n=15)DSCCs were selected.High DSCC cows had higher levels of red blood cell counts(P<0.05),hemoglobin(P=0.07),and hematocrit(P=0.05),higher concentrations of serum oxidative variables[reactive oxygen species(P<0.05),malondialdehyde(P<0.05),protein carbonyl(P<0.05),and 8-hydroxy-2-deoxyguanosine(P=0.07)],higher levels of serum and milk NETs(P<0.05)and blood-milk barrier indicators,including serumβ-casein(P=0.05)and milk immunoglobulin G2(P=0.09),than those of low DSCC cows.In addition,lower concentrations of serum nutrient metabolites(cholesterol and albumin)(P<0.05)and a lower level of serum deoxyribonuclease I(P=0.09)were observed in high DSCC cows than in low DSCC cows.Among the assessments performed using levels of the three prepartum serum parameters(NETs,deoxyribonuclease I andβ-casein),the area under the curve(0.973)of NETs was the highest.In addition,the sensitivity(1.00)and specificity(0.93)were observed for the discrimination of these cows using NETs levels with a critical value of 32.2 ng/mL(P<0.05).Conclusions:The formation of NETs in blood in transition dairy cows may damage the integrity of the blood-milk barrier and thereby increase the risk for mastitis in postpartum cows.

Inhibiting the formation of neutrophil extracellular trapping: a potential mechanism of Chinese medicine in the treatment of ischemic stroke

Ischemic stroke(IS)is the main killer that endangers the health and life of middle-aged and elderly people worldwide.Inflammatory response plays a key regulatory role in the pathogenesis of IS.After cerebral ischemia,leukocytes rapidly accumulate,penetrate blood vessels and infiltrate brain tissue,thereby activating pro-inflammatory factors in the infarct area to exacerbate nerve damage.Neutrophil extracellular traps(NETs)are fibrous mesh structures released by activated neutrophils outside the cell,which can clear pathogens and cell debris,induce inflammatory responses and exacerbate cerebral ischemia-reperfusion(CI/R)injury.Various traditional Chinese medicines and their main components can improve neurological function defects after IS,and inhibit the formation of NETs,which opens up a new direction for the study of traditional Chinese medicines in the prevention and treatment of IS.

Neutrophil extracellular traps mediate the crosstalk between glioma progression and the tumor microenvironment via the HMGB1/RAGE/IL-8 axis

Objective:Neutrophil extracellular traps(NETs)produced by tumor-infiltrating neutrophils(TINs)are associated with poor prognosis in patients with several types of cancer.However,the mechanisms underlying the involvement of NETs in glioma progression remain largely unknown.This study aimed to elucidate the roles of NETs in biological processes that drive the crosstalk between glioma progression and the tumor microenvironment.Methods:Neutrophil infiltration and NETs formation were investigated in glioma tissue through immunohistochemistry,and their relationships with clinicopathological features and outcomes were statistically evaluated.The effects of NETs on glioma cell progression were studied in a co-culture system.In vivo and in vitro experiments validated the reactive oxygen species activity and cytokine production of TINs,as well as the ERK signaling pathway activation and the metastasis of gliomas.Results:Neutrophil infiltration and NETs formation were induced in high-grade glioma compared with low-grade glioma.NETs induced by TINs were determined to be an oncogenic marker of high-grade gliomas and to be involved in cell proliferation and invasion.NETs overproduction promoted glioma cell proliferation,migration,and invasion.Furthermore,HMGB1 was found to bind to RAGE and activate the NF-κB signaling pathway in vitro.In addition,NETs stimulated the NF-κB signaling pathway,thus promoting IL-8 secretion in glioblastoma.Subsequently,IL-8 recruited neutrophils which in turn mediated NETs formation via the PI3 K/AKT/ROS axis in TINs.Conclusions:Our results suggest that NETs produced by TINs mediate the crosstalk between glioma progression and the tumor microenvironment by regulating the HMGB1/RAGE/IL-8 axis.Targeting NETs formation or IL-8 secretion may be an effective approach to inhibit glioma progression.

Neutrophil extracellular traps participate in the development of cancer-associated thrombosis in patients with gastric cancer

BACKGROUND The development of venous thromboembolism(VTE) is associated with high mortality among gastric cancer(GC) patients. Neutrophil extracellular traps(NETs) have been reported to correlate with the prothrombotic state in some diseases, but are rarely reported in GC patients.AIM To investigate the effect of NETs on the development of cancer-associated thrombosis in GC patients.METHODS The levels of NETs in blood and tissue samples of patients were analyzed by ELISA, flow cytometry, and immunofluorescence staining. NET generation and hypercoagulation of platelets and endothelial cells(ECs) in vitro were observed by immunofluorescence staining. NET procoagulant activity(PCA) was determined by fibrin formation and thrombin–antithrombin complex(TAT) assays.Thrombosis in vivo was measured in a murine model induced by flow stenosis in the inferior vena cava(IVC).RESULTS NETs were likely to form in blood and tissue samples of GC patients compared with healthy individuals. In vitro studies showed that GC cells and their conditioned medium, but not gastric mucosal epithelial cells, stimulated NET release from neutrophils. In addition, NETs induced a hypercoagulable state of platelets by upregulating the expression of phosphatidylserine and Pselectin on the cells. Furthermore, NETs stimulated the adhesion of normal platelets on glass surfaces. Similarly, NETs triggered the conversion of ECs to hypercoagulable phenotypes by downregulating the expression of their intercellular tight junctions but upregulating that of tissue factor. Treatment of normal platelets or ECs with NETs augmented the level of plasma fibrin formation and the TAT complex. In the models of IVC stenosis, tumor-bearing mice showed a stronger ability to form thrombi, and NETs abundantly accumulated in the thrombi of tumorbearing mice compared with control mice. Notably, the combination of deoxyribonuclease I,activated protein C, and sivelestat markedly abolished the PCA of NETs.CONCLUSION GC-induced NETs strongly increased the risk of VTE development both in vitro and in vivo. NETs are potential therapeutic targets in the prevention and treatment of VTE in GC patients.

Neutrophil extracellular traps in gastrointestinal cancer

Gastrointestinal(GI)cancer is a high-risk malignancy and is characterized by high mortality and morbidity worldwide.Neutrophil extracellular traps(NETs),a weblike structure consisting of chromatin DNA with interspersed cytoplasmic and granule proteins,are extruded by activated neutrophils to entrap and kill bacteria and fungi.However,accumulating evidence shows that NETs are related to the progression and metastasis of cancer.In clinical studies,NETs infiltrate primary GI cancer tissues and are even more abundant in metastatic lesions.The quantity of NETs in peripheral blood is revealed to be associated with ascending clinical tumour stages,indicating the role of NETs as a prognostic markers in GI cancer.Moreover,several inhibitors of NETs or NET-related proteins have been discovered and used to exert anti-tumour effects in vitro or in vivo,suggesting that NETs can be regarded as targets in the treatment of GI cancer.In this review,we will focus on the role of NETs in gastric cancer and colorectal cancer,generalizing their effects on tumour-related thrombosis,invasion and metastasis.Recent reports are also listed to show the latest evidences of how NETs affect GI cancer.Additionally,notwithstanding the scarcity of systematic studies elucidating the underlying mechanisms of the interaction between NETs and cancer cells,we highlight the potential importance of NETs as biomarkers and anti-tumour therapeutic targets.

Do neutrophil extracellular traps contribute to the heightened risk of thrombosis in inflammatory diseases?

Thrombotic events,both arterial and venous,are a major health concern worldwide. Further,autoimmune diseases,such as systemic lupus erythematosus,anti-neutrophil cytoplasmic antibody(ANCA)-associated vasculitis,and antiphospholipid syndrome,predispose to thrombosis,and thereby push the risk for these morbid events even higher. In recent years,neutrophils have been identified as important players in both arterial and venous thrombosis. Specifically,chromatin-based structures called neutrophil extracellular traps(NETs) play a key role in activating the coagulation cascade,recruiting platelets,and serving as scaffolding upon which the thrombus can be assembled. At the same time,neutrophils and NETs are emerging as important mediators of pathogenic inflammation in the aforementioned autoimmune diseases. Here,we first review the general role of NETs in thrombosis. We then posit that exaggerated NET release contributes to the prothrombotic diatheses of systemic lupus erythematosus,ANCA-associated vasculitis,and antiphospholipid syndrome.

Neutrophil extracellular traps in the intestinal mucosa of Eimeria-infected animals

Objective:To investigate the presence of neutrophil extracellular traps(NETs) in vivo by analysing intestinal sections from experimentally Eimeria bovis-and naturally Eimeria arloingi-infected animals.Methods:Intestinal samples of Eimeria arloingi-and Eimeria bovis-infected animals were analysed by using immunohistochemical and fluorescence approach by using monoclonal antibodies.Results:Classical NET components were confirmed by co-localization of extracellular DNA being decorated with neutrophil elastase and histones in Eimeria-infected tissue samples.Here,extrusion of NETs was exclusively detected in intestinal polymorphonuclear neutrophils infiltrating Eimeria-infected sites.In vivo NETs were either found in close proximity or in direct contact to different Eimeria stages suggesting a stage-independent process.NETs were also found within the gut lumen driven by polymorphonuclear neutrophils that were contacting released oocysts.Conclusions:We postulate that NETs might play an important role in innate defence reactions in coccidiosis therefore significantly altering the outcome of infection.

Icaritin inhibits the progression of urothelial cancer by suppressing PADI2-mediated neutrophil infiltration and neutrophil extracellular trap formation

Tumor relapse and metastasis are the major causes of mortality associated with urothelial cancer.In the tumor microenvironment,negative regulatory molecules and various immune cell subtypes suppress antitumor immunity.The inflammatory microenvironment,associated with neutrophils and neutrophil extracellular traps(NETs),promotes tumor metastasis.However,no drugs are currently available to specifically inhibit neutrophils and NETs.In this study,we first demonstrated that icaritin(ICT),a Chinese herbal remedy that is a first-line treatment for advanced and incurable hepatocellular carcinoma,reduces NETs caused by suicidal NETosis and prevents neutrophil infiltration in the tumor microenvironment.Mechanistically,ICT binds to and inhibits the expression of PADI2 in neutrophils,thereby suppressing PADI2-mediated histone citrullination.Moreover,ICT inhibits ROS generation,suppresses the MAPK signaling pathway,and inhibits NET-induced tumor metastasis.Simultaneously,ICT inhibits tumoral PADI2-mediated histone citrullination,which consequently suppresses the transcription of neutrophil-recruiting genes such as GM-CSF and IL-6.The downregulation of IL-6 expression,in turn,forms a regulatory feedback loop through the JAK2/STAT3/IL-6 axis.Through a retrospective study of clinical samples,we found a correlation between neutrophils,NETs,UCa prognosis,and immune evasion.Combining ICT with immune checkpoint inhibitors may have synergistic effects.In summary,our study demonstrated that ICT could be a novel inhibitor of NETs and a novel UCa treatment.

Association of the immediate perioperative dynamics of circulating DNA levels and neutrophil extracellular traps formation in cancer patients

Objectives:Elevated circulating DNA(cirDNA)concentrations were found to be associated with trauma or tissue damage which suggests involvement of inflammation or cell death in post-operative cirDNA release.We carried out the first prospective,multicenter study of the dynamics of cirDNA and neutrophil extracellular trap(NETs)markers during the perioperative period from 24 h before surgery up to 72 h after curative surgery in cancer patients.Methods:We examined the plasma levels of two NETs protein markers[myeloperoxidase(MPO)and neutrophil elastase(NE)],as well as levels of cirDNA of nuclear(cir-nDNA)and mitochondrial(cir-mtDNA)origin in 29 colon,prostate,and breast cancer patients and in 114 healthy individuals(HI).Results:The synergistic analytical information provided by these markers revealed that:(i)NETs formation contributes to post-surgery conditions;(i)post-surgery cir-nDNA levels were highly associated with NE and MPO in colon cancer[r=0.60(P<0.001)and r=0.53(P<0.01),respectivelyl,but not in prostate and breast cancer;(i)each tumor type shows a specific pattern of cir-nDNA and NETs marker dynamics,but overall the pre-and post-surgery median values of cir-nDNA,NE,and MPO were significantly higher in cancer patients than in HI.Conclusion:Taken as a whole,our work reveals the association of NETs formation with the elevated cir-nDNA release during a cancer patient's perioperative period,depending on surgical procedure or cancer type.By contrast,cir-mtDNA is poorly associated with NETs formation in the studied perioperative period,which would appear to indicate a different mechanism of release or suggest mitochondrial dysfunction.

A crucial role of neutrophil extracellular traps in pulmonary infectious diseases

Neutrophil extracellular traps(NETs),extrusions of intracellular DNA with attached granular material that exert an antibacterial effect through entangling,isolating,and immobilizing microorganisms,have been extensively studied in recent decades.The primary role of NETs is to entrap and facilitate the killing of bacteria,fungi,viruses,and parasites,preventing bacterial and fungal dissemination.NET formation has been described in many pulmonary diseases,including both infectious and non-infectious.NETs are considered a double-edged sword.As innate immune cells,neutrophils release NETs to kill pathogens and remove cellular debris.However,the dele-terious effects of excessive NET release in lung disease are particularly important because NETs and by-products of NETosis can directly induce epithelial and endothelial cell death while simultaneously inducing inflammatory cytokine secretion and immune-mediated thrombosis.Thus,NET formation must be tightly regulated to preserve the anti-microbial capability of NETs while minimizing damage to the host.In this review,we summarized the recent updates on the mechanism of NETs formation and pathophysiology associated with excessive NETs,aiming to provide insights for research and treatment of pulmonary infectious diseases.

Hsa_circ_0036740 in familial adenomatous polyposis:Immune regulation and neutrophil effects in CRC based on highthroughput assay

Familial adenomatous polyposis(FAP)is an autosomal dominant disease with a high probability of becoming cancerous.Many RNAs potentially associated with FAP have not been identified.In this study,a circRNA(circular RNA)expression profile of FAP was established using a circRNA microarray,and differentially expressed circRNAs were verified by RT-qPCR.The effects of hsa_circ_0036740 on the malignant behavior of tumor cells(proliferation,apoptosis,and epithelial mesenchymal transition)and the levels of C3A complement protein expression were evaluated.Moreover,neutrophils were isolated and co-cultured with colorectal cancer cells(CRCs),followed by measurements of MPO-DNA,citrullinated histone H3,interleukin(IL)-1β,IL-6,and IL-8 levels.Nuclear translocation of arginine deiminase 4(PAD4)was observed using immunofluorescence assays.Based on the high-throughput assay,238 downregulated circRNAs,and 38 upregulated circRNAs were identified.A Kyoto Encyclopedia of Genes and Genomes enrichment analysis suggested that immune regulation might be involved in FAP.A total of 10 DECs(differentially expressed circular RNAs)were identified by RT-qPCR,and among them,hsa_circ_0036740 showed the highest fold-change in upregulation.Results of gain-of-and loss-of-function studies revealed that hsa_circ_0036740 enhanced the malignant behavior of tumor cells,such as metastasis,proliferation,and apoptosis,with an increasing level of C3A complement.Moreover,hsa_circ_0036740 also significantly increased neutrophil extracellular trap formation and inflammation in neutrophils,as shown by an increased expression of PAD4.In conclusion,this study revealed the expression profiles of circRNAs in FAP and confirmed the possible involvement of hsa_circ_0036740 in the immune regulation mediated by neutrophils.Finally,hsa_circ_0036740 was suggested as a new therapeutic target for CRC.

防风石油醚提取物调节中性粒细胞胞外诱捕网对类风湿性关节炎大鼠的改善作用及机制

目的 探究防风石油醚提取物通过调节中性粒细胞胞外诱捕网(NETs)对类风湿性关节炎(RA)大鼠的改善作用及机制。方法 采用牛Ⅱ型胶原与弗氏完全佐剂建立大鼠RA模型。将造模成功的大鼠随机分为模型组和防风石油醚提取物低、中、高剂量组(55、110、220 mg/kg),另设不造模的正常组,每组10只。各组大鼠灌胃相应药液或等体积2%吐温-80溶液,每天1次,连续28 d。观察大鼠足趾肿胀度并进行关节炎指数(AI)评分,检测大鼠血清中白细胞介素1β(IL-1β)、IL-10、IL-17、肿瘤坏死因子α(TNF-α)、25-羟基维生素D_3[25(OH)D_3]、髓过氧化物酶(MPO)、中性粒细胞弹性蛋白酶(NE)和NETs的水平,观察大鼠踝关节病理学形态变化,检测大鼠踝关节中瓜氨酸化组蛋白H3(CitH3)以及滑膜组织中细胞色素P450 24A1(CYP24A1)、细胞色素P45027B1(CYP27B1)、维生素D受体(VDR)、肽基精氨酸脱亚胺酶4(PAD4)的表达水平。结果 与模型组比较,防风石油醚提取物中、高剂量组大鼠给药后第14天至第28天的足趾肿胀度和AI评分均显著降低(P<0.05或P<0.01);血清中IL-1β、IL-17、TNF-α、MPO、NE和NETs水平均显著降低,IL-10、25(OH)D_3水平均显著升高(P<0.05或P<0.01);踝关节间隙变宽,结构明显改善;踝关节中CitH3以及滑膜组织中CYP24A1、PAD4表达水平均显著降低,滑膜组织中CYP27B1、VDR表达水平均显著升高(P<0.05或P<0.01)。结论 防风石油醚提取物可能通过调控维生素D系统,抑制NETs生成,进而改善RA症状。

缺氧诱导的胃癌细胞外泌体通过促进中性粒细胞胞外诱捕网的形成对胃癌细胞增殖能力的影响

目的探究缺氧条件下胃癌细胞外泌体(exosome,exo)诱导的中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)对胃癌细胞生长的影响。方法提取正常和缺氧培养条件下SGC-7901和HGC细胞分泌的外泌体(记为N-SGC-7901 exo、N-HGC exo、H-SGC-7901 exo和H-HGC exo),中性粒细胞分为磷酸盐缓冲溶液(phosphate buffered solution,PBS)组、N-SGC-7901组、N-HGC组、H-SGC-7901组、H-HGC组、N-SGC-7901 exo组、N-HGC exo组、H-SGC-7901 exo组、H-HGC exo组,Sytox Green染色检测各组细胞NETs的形成。SGC-7901细胞分为PBS/培养液(culture medium,CM)组、N-SGC-7901 exo/CM组、H-SGC-7901 exo/CM组、H-SGC-7901 exo/CM+DNAse组,HGC细胞分为PBS/CM组、N-HGC exo/CM组、H-HGC exo/CM组和H-HGC exo+DNAse/CM组。CCK8检测SGC-7901和HGC细胞增殖能力,克隆形成实验检测各组细胞克隆形成能力。结果相比于PBS组,N-SGC-7901组、H-SGC-7901组、N-HGC组、H-SGC组中性粒细胞NETs增加,且H-SGC-7901组高于N-SGC-7901组,H-SGC组高于N-HGC组。相比于PBS组,N-SGC-7901 exo组、H-SGC-7901 exo组、N-HGC exo组、H-SGC exo组中性粒细胞NETs增加,且H-SGC-7901 exo组高于N-SGC-7901 exo组,H-SGC exo组高于N-HGC exo组。相比于PBS/CM组,N-SGC-7901 exo/CM组和H-SGC-7901 exo/CM组SGC-7901细胞增殖和克隆形成能力显著增加(P<0.01),并且H-SGC-7901 exo/CM组高于N-SGC-7901 exo/CM组(P<0.001),而H-SGC-7901 exo/CM+DNase组增殖和克隆形成能力显著低于H-SGC-7901 exo/CM组。相比于PBS/CM组,N-HGC exo/CM组和H-HGC exo/CM组HGC细胞增殖和克隆形成能力显著增加(P<0.01),并且H-HGC exo/CM组高于N-HGC exo/CM组(P<0.001),H-HGC exo/CM+DNase组增殖和克隆形成能力显著低于H-HGC exo/CM组。结论缺氧条件下胃癌细胞外泌体通过促进NETs形成而促进胃癌细胞的生长。

蝮蛇咬伤对中性粒细胞NETs和炎症损伤影响的临床研究

目的探讨蝮蛇咬伤后中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)标志物嗜中性粒细胞弹性蛋白酶(neutrophil elastase,NE)以及细胞游离DNA(cell free DNA,cf-DNA)变化和与炎症标志物及组织损伤标志物的相关性。方法选取2021年9月—2022年12月杭州市中医院皮肤科收治的蝮蛇咬伤患者作为研究对象,研究包括36例蝮蛇咬伤患者,20例健康体检者;比较两组中性粒细胞、淋巴细胞计数、嗜中性粒细胞弹性蛋白酶(neutrophil elastase,NE)、细胞游离DNA(cell free DNA,cf-DNA)、血清淀粉样蛋白A(serum amyloid A,SAA)、C反应蛋白(C-reactive protein,CRP)、中性粒细胞淋巴细胞比值(neutrophil-to-lymphocyte ratio,NLR)、肌酸激酶(creatine kinase,CK)、肌酸肌酶同工酶(creatine kinase-MB,CKMB)、天门冬氨酸转氨酶(aspartic transaminase,AST)和乳酸脱氢酶(lactate dehydrogenase,LDH)水平,计算Pearson相关系数并利用Python软件编写代码绘制热力图、箱线图,分析中性粒细胞计数与NETs标志物、炎症标志物和组织损伤标志物之间的相关性。结果蝮蛇咬伤后中性粒细胞计数升高,NETs标志物NE、cf-DNA升高,CRP、SAA、NLR、AST升高,淋巴细胞计数降低。蝮蛇咬伤后中性粒细胞数值与NE酶、cf-DNA血清含量呈正相关,而与炎标志物CRP和SAA之间没有明显相关性;而CRP与SAA、CKMB与LDH强正相关,CK与NE、SAA与NE之间呈正相关,淋巴细胞数与NLR呈负相关。结论蝮蛇咬伤可能引起NETs水平上升,促进炎症加重和组织损伤。

中性粒细胞胞外诱捕网形成与清除机制及其在肝脏损伤中的作用

中性粒细胞胞外诱捕网(NETs)是中性粒细胞除吞噬和脱颗粒作用之外,近年来发现的另一种捕获清除病原体,发挥抗感染作用的重要手段。研究发现,NETs除了与免疫防御有关,还参与血栓、癌症等的发生发展。本文就NETs的形成与清除机制,及其在酒精相关性肝病、非酒精性脂肪性肝病、肝移植以及肝癌等肝脏损伤中作用研究进行综述,以期为寻找肝损伤预防与治疗的新靶点提供参考。

中性粒细胞胞外诱捕网在脓毒症病理生理及临床应用中的研究进展

脓毒症是危害性极强的临床综合征,其复杂的病理生理机制及随之而来的治疗难题一直是人们的困扰。中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)是中性粒细胞在激发状态下产生的一种以核DNA、组蛋白为主要支架并包含多种酶及炎性因子的物质集合体。这些丰富的炎性物质与脓毒症发生发展的多种炎症反应途径有千丝万缕的联系,也成为脓毒症研究的重要突破方向。近年来,特别是新冠肺炎流行以来,NETs在脓毒症时的产生机制及临床应用的研究如雨后春笋,相关机制及途径逐渐明晰,治疗脓毒症的新方向不断涌现。该文针对NETs的形成过程及其在不同刺激下的变异,在脓毒症发生发展中可能发挥的作用及其潜在的临床应用价值,以及针对NETs及其组分的脓毒症治疗新思路进行综述。