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 extracellu...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.展开更多
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 t...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.展开更多
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 t...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.展开更多
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 s...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.展开更多
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 involveme...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.展开更多
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 prothromboti...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.展开更多
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:Intestin...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.展开更多
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 intersperse...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.展开更多
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 an...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.展开更多
Background:Neutrophil extracellular traps(NETs)are considered significant contributors to cancer progression,especially metastasis.However,it is still unclear whether NETs are involved in hepatitis B virus(HBV)-relate...Background:Neutrophil extracellular traps(NETs)are considered significant contributors to cancer progression,especially metastasis.However,it is still unclear whether NETs are involved in hepatitis B virus(HBV)-related hepatocarcinogenesis and have potential clinical significance during evaluation and management for hepatocellular carcinoma(HCC).In this study,we aimed to investigate the functional mechanism of NETs in HBV-related hepatocarcinogenesis and their clinical significance.Methods:A total of 175 HCC patients with and without HBV infection and 58 healthy controls were enrolled in this study.NETs weremeasured in tissue specimens,freshly isolated neutrophils and blood serum from these patients,and the correlation of circulating serum NETs levels with malignancy was evaluated.The mechanism by which HBV modulates NETs formation was explored using cell-based studies.In addition,in vitro and in vivo experiments were further performed to clarify the functional mechanism of NETs on the growth and metastasis of HCC.Results:We observed an elevated level of NETs in blood serum and tissue specimens from HCC patients,especially those infected with HBV.NETs facilitated the growth and metastasis of HCC both in vitro and in vivo,which were mainly dominated by increased angiogenesis,epithelial-mesenchymal transition(EMT)-related cell migration,matrix metalloproteinases(MMPs)-induced extracellular matrix(ECM)degradation and NETs-mediated cell trapping.Inhibition of NETs generation by DNase 1 effectively abrogated the NETs-aroused HCC growth and metastasis.In addition,HBV-induced S100A9 accelerated the generation of NETs,which was mediated by activation of toll-like receptor(TLR4)/receptor for advanced glycation end products(RAGE)-reactive oxygen species(ROS)signaling.Further,circulatory NETs were found to correlate with viral load,TNM stage and metastasis status in HBV-related HCC,and the identified NETs could predict extrahepatic metastasis,with an area under the ROC curve(AUC)of 0.83 and 90.3%sensitivity and 62.8%specificity at a cutoff value of 0.32.Conclusions:Our findings indicated that activation of RAGE/TLR4-ROS signaling by HBV-induced S100A9 resulted in abundant NETs formation,which subsequently facilitated the growth and metastasis of HCC cells.More importantly,the identified circulatory NETs exhibited potential as an alternative biomarker for predicting extrahepatic metastasis in HBV-related HCC.展开更多
Neutrophil extracellular traps (NETs) participate in the rapid inhibition and clearance of pathogens during infection;however, the molecular regulation of NET formation remains poorly understood. In the current study,...Neutrophil extracellular traps (NETs) participate in the rapid inhibition and clearance of pathogens during infection;however, the molecular regulation of NET formation remains poorly understood. In the current study, we found that inhibition of the wild-type p53-induced phosphatase 1 (Wip1) significantly suppressed the activity of Staphylococcus aureus (S. aureus) and accelerated abscess healing in S. aureus-induced abscess model mice by enhancing NET formation. A Wip1 inhibitor significantly enhanced NET formation in mouse and human neutrophils in vitro. High-resolution mass spectrometry and biochemical assays demonstrated that Coro1a is a substrate of Wip1. Further experiments also revealed that Wip1 preferentially and directly interacts with phosphorylated Coro1a than compared to unphosphorylated inactivated Coro1a. The phosphorylated Ser426 site of Coro1a and the 28–90 aa domain of Wip1 are essential for the direct interaction of Coro1a and Wip1 and for Wip1 dephosphorylation of p-Coro1a Ser426. Wip1 deletion or inhibition in neutrophils significantly upregulated the phosphorylation of Coro1a-Ser426, which activated phospholipase C and subsequently the calcium pathway, the latter of which promoted NET formation after infection or lipopolysaccharide stimulation. This study revealed Coro1a to be a novel substrate of Wip1 and showed that Wip1 is a negative regulator of NET formation during infection. These results support the potential application of Wip1 inhibitors to treat bacterial infections.展开更多
The widespread use of orthopedic implants to support or replace bones is increasingly threatened by the risk of incurable bacterial infections,impenetrable microbial biofilms,and irreversible antibiotic resistance.In ...The widespread use of orthopedic implants to support or replace bones is increasingly threatened by the risk of incurable bacterial infections,impenetrable microbial biofilms,and irreversible antibiotic resistance.In the past,the development of anti-infective biomaterials focused solely on direct antibacterial properties while ignoring the host’s immune response.Inspired by the clearance of infection by the innate neutrophil response and partici-pation in anti-infectious immunity of Zn ions,we report an innovative neutrophil extracellular traps(NETs)strategy,induced by biodegradable pure Zn,which achieved therapeutic efficacy toward biomaterial-related infections.Our in vitro and in vivo data showed that pure Zn was favorable for NETs formation by promoting the release of DNA fibers and granule proteins in a reactive oxygen species(ROS)-dependent manner,thereby retraining and degrading bacteria with an efficiency of up to 99.5%.Transcriptome analysis revealed that cytoskeletal rearrangement and toll-like receptor(TLR)signaling pathway were also involved in Zn-induced NETs formation.Furthermore,the in vivo results of a Staphylococcus aureus(S.aureus)-infected rat model veri-fied that pure Zn potentiated the bactericidal capability of neutrophils around implants,and promoted osseointegration in S.aureus-infected rat femurs.This antibacterial immunity concept lays a foundation for the development of other antibacterial biomaterials and holds great promise for treating orthopedic infections.展开更多
Background:Inflammation is an important factor in pathological scarring.The role of neutrophils,one of the most important inflammatory cells,in scar hyperplasia remains unclear.The purpose of this article is to study ...Background:Inflammation is an important factor in pathological scarring.The role of neutrophils,one of the most important inflammatory cells,in scar hyperplasia remains unclear.The purpose of this article is to study the correlation between neutrophil extracellular traps(NETs)and scar hyperplasia and identify a new target for inhibiting scar hyperplasia.Methods:Neutrophils were isolated from human peripheral blood by magnetic-bead sorting.NETs in plasma and scars were detected by enzyme-linked immunosorbent assays(ELISAs),immunofluorescence and flow cytometry.Immunohistochemistry was used to assess neutrophil(CD66B)infiltration in hypertrophic scars.To observe the entry of NETs into fibroblasts we used immunofluorescence and flow cytometry.Results:We found that peripheral blood neutrophils in patients with hypertrophic scars were more likely to form NETs(p<0.05).Hypertrophic scars showed greater infiltration with neutrophils and NETs(p<0.05).NETs activate fibroblasts in vitro to promote their differentiation and migration.Inhibition of NETs with cytochalasin in wounds reduced the hyperplasia of scars in mice.We induced neutrophils to generate NETs with different stimuli in vitro and detected the proteins carried by NETs.We did not find an increase in the expression of common scarring factors[interleukin(IL)-17 and transforming growth factor-β(TGF-β),p>0.05].However,inhibiting the production of NETs or degrading DNA reduced the differentiation of fibroblasts intomyofibroblasts.In vitro,NETs were found to be mediated by Toll-like receptor 9(TLR-9)in fibroblasts and further phosphorylated nuclear factor Kappa-B(NF-κB).We found that IL-6,which is downstream of NF-κB,was increased in fibroblasts.Additionally,IL-6 uses autocrine and paracrine signaling to promote differentiation and secretion.Conclusions:Our experiments found that NETs activate fibroblasts through the TLR-9/NF-κB/IL-6 pathway,thereby providing a new target for regulating hypertrophic scars.展开更多
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,...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.展开更多
Severe acute pancreatitis(SAP)is a life-threatening acute abdominal disease with two peaks of death:the first in the early stage,characterized by systemic inflammatory response-associated organ failure;and the second ...Severe acute pancreatitis(SAP)is a life-threatening acute abdominal disease with two peaks of death:the first in the early stage,characterized by systemic inflammatory response-associated organ failure;and the second in the late stage,characterized by infectious complications.Neutrophils are the main immune cells participating in the whole process of SAP.In addition to the traditional recognition of neutrophils as the origination of chemokine and cytokine cascades or phagocytosis and degranulation of pathogens,neutrophil extracellular traps(NETs)also play an important roles in inflammatory reactions.We reviewed the role of NETs in the occurrence and development of SAP and its fatal complications,including multiple organs injury,infected pancreatic necrosis,and thrombosis.This review provides novel insights into the involvement of NETs throughout the entire process of SAP,showing that targeting NETs might be a promising strategy in SAP treatment.However,precision therapeutic options targeting NETs in different situations require further investigation.展开更多
African trypanosomatid parasites escape host acquired immune responses through periodic antigenic variation of their surface coat.In this study,we describe a mechanism by which the parasites counteract innate immune r...African trypanosomatid parasites escape host acquired immune responses through periodic antigenic variation of their surface coat.In this study,we describe a mechanism by which the parasites counteract innate immune responses.Two Tat D DNases were identified in each of Trypanosoma evansi and Trypanosoma brucei.These DNases are bivalent metal-dependent endonucleases localized in the cytoplasm and flagella of the parasites that can also be secreted by the parasites.These enzymes possess conserved functional domains and have efficient DNA hydrolysis activity.Host neutrophil extracellular traps(NETs)induced by the parasites could be hydrolyzed by native and recombinant Tat D DNases.NET disruption was prevented,and the survival rate of parasites was decreased,in the presence of the DNase inhibitor aurintricarboxylic acid.These data suggest that trypanosomes can counteract host innate immune responses by active secretion of Tat D DNases to degrade NETs.展开更多
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 extensivel...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.展开更多
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...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.展开更多
基金supported by the National Natural Science Foundation of China,No.82271399(to XC)the Project of Tianjin Applied Basic and Multiple Support Research,No.21JCZDJC00910(to XC)+4 种基金the Scientific Research Program of Tianjin Education Commission(Natural Science)of China,No.2019ZD034(to QD)the Science&Technology Program of Tianjin for Cultivation of Innovative Talents,No.22JRRCRC00020(to QD)the Tianjin Medical University"Clinical Talent Training 123 Climbing Plan"(to XC)the Tianjin Health Care Elite Prominent Young Doctor Development Program(to XC)the Young and Middle-aged Backbone Innovative Talent Program(to XC)。
文摘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.
基金supported by grants from the National Traditional Chinese Medicine Inheritance and Innovation Project Fund(Development and Reform Office[2022]366)National Key Discipline of Traditional Chinese Medicine(Traditional Chinese Medicine[2023]No.85)+2 种基金the Ministry of Science and Technology National Key Research and Development Program Chinese Medicine Modernization Research Key Project(2018YFC1705204)National Nature Fund Program(82074373,82274490,82205090)Anhui Provincial Laboratory of Applied Basis and Development of Internal Medicine of Modern Traditional Chinese Medicine(2016080503B041).
文摘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.
基金This work was supported by grants from Guangxi Medical High-level Key Talents/139/(No.G201901010)Natural Science Foundation of Guangxi Province(No.GXNSFDA198008).
文摘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.
基金financially supported by grants from the China-USA Intergovernmental Collaborative Project in S&T Innovation under the National Key R&D Program (No.2018YFE0111700,Beijing)。
文摘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.
基金supported by The National Natural Science Foundation of China(Grant No.81702972,Grant No.81874204)China Postdoctoral Science Foundation(Grant No.2018M640305,Grant No.2019M660074)+4 种基金The Research Project of the Chinese Society of Neuro-oncology,CACA(Grant No.CSNO-2016-MSD12)Heilongjiang Postdoctoral Science Foundation(Grant No.LBH-Z18103)The Research Project of the Health and Family Planning Commission of Heilongjiang Province(Grant No.2017–201)Postgraduate Research&Practice Innovation Program of Harbin Medical University(Grant No.YJSKYCX2018-94HYD)The Young and middle-aged Science Foundation of Harbin Medical University(Grant No.KYCX2018-08)。
文摘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.
基金Supported by National Natural Science Foundation of China,No.81672355.
文摘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.
基金Supported by the German Research Foundation(DFG,Grant No.TA 219/4-1)
文摘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.
基金Supported by Natural Science Foundation of Beijing for Youth,No.7214252Program of Military Medicine for Youth,No.QNF19055.
文摘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.
基金Supported by NIH K08AR066569a career development award from the Burroughs Wellcome Fund(Knight JS)Kazzaz NM was supported by Security Forces Hospital Program,Ministry of Interior,Riyadh,Saudi Arabia
文摘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.
基金the National Natural Science Foundation of China(82072364 and 82002152)the Chongqing medical scientific research project(Joint project of Chongqing Health Commission and Science and Technology Bureau,2020FYYX038)Kuanren Talents Program of the second affiliated hospital of Chongqing Medical University and Senior Medical Talents Programof Chongqing for Young and Middle-aged(2022-15).
文摘Background:Neutrophil extracellular traps(NETs)are considered significant contributors to cancer progression,especially metastasis.However,it is still unclear whether NETs are involved in hepatitis B virus(HBV)-related hepatocarcinogenesis and have potential clinical significance during evaluation and management for hepatocellular carcinoma(HCC).In this study,we aimed to investigate the functional mechanism of NETs in HBV-related hepatocarcinogenesis and their clinical significance.Methods:A total of 175 HCC patients with and without HBV infection and 58 healthy controls were enrolled in this study.NETs weremeasured in tissue specimens,freshly isolated neutrophils and blood serum from these patients,and the correlation of circulating serum NETs levels with malignancy was evaluated.The mechanism by which HBV modulates NETs formation was explored using cell-based studies.In addition,in vitro and in vivo experiments were further performed to clarify the functional mechanism of NETs on the growth and metastasis of HCC.Results:We observed an elevated level of NETs in blood serum and tissue specimens from HCC patients,especially those infected with HBV.NETs facilitated the growth and metastasis of HCC both in vitro and in vivo,which were mainly dominated by increased angiogenesis,epithelial-mesenchymal transition(EMT)-related cell migration,matrix metalloproteinases(MMPs)-induced extracellular matrix(ECM)degradation and NETs-mediated cell trapping.Inhibition of NETs generation by DNase 1 effectively abrogated the NETs-aroused HCC growth and metastasis.In addition,HBV-induced S100A9 accelerated the generation of NETs,which was mediated by activation of toll-like receptor(TLR4)/receptor for advanced glycation end products(RAGE)-reactive oxygen species(ROS)signaling.Further,circulatory NETs were found to correlate with viral load,TNM stage and metastasis status in HBV-related HCC,and the identified NETs could predict extrahepatic metastasis,with an area under the ROC curve(AUC)of 0.83 and 90.3%sensitivity and 62.8%specificity at a cutoff value of 0.32.Conclusions:Our findings indicated that activation of RAGE/TLR4-ROS signaling by HBV-induced S100A9 resulted in abundant NETs formation,which subsequently facilitated the growth and metastasis of HCC cells.More importantly,the identified circulatory NETs exhibited potential as an alternative biomarker for predicting extrahepatic metastasis in HBV-related HCC.
基金supported by grants from the National Natural Science Foundation for General and Key Programs(31930041,YZ)the National Key Research and Development Program of China(2017YFA0105002,2017YFA0104401,2017YFA0104402,YZ)+1 种基金the Knowledge Innovation Program of the Chinese Academy of Sciences(XDA16030301,YZ)the Doctoral Research Foundation Project of Affiliated Hospital of Guizhou Medical University(gyfybsky-2022-1,WZ)。
文摘Neutrophil extracellular traps (NETs) participate in the rapid inhibition and clearance of pathogens during infection;however, the molecular regulation of NET formation remains poorly understood. In the current study, we found that inhibition of the wild-type p53-induced phosphatase 1 (Wip1) significantly suppressed the activity of Staphylococcus aureus (S. aureus) and accelerated abscess healing in S. aureus-induced abscess model mice by enhancing NET formation. A Wip1 inhibitor significantly enhanced NET formation in mouse and human neutrophils in vitro. High-resolution mass spectrometry and biochemical assays demonstrated that Coro1a is a substrate of Wip1. Further experiments also revealed that Wip1 preferentially and directly interacts with phosphorylated Coro1a than compared to unphosphorylated inactivated Coro1a. The phosphorylated Ser426 site of Coro1a and the 28–90 aa domain of Wip1 are essential for the direct interaction of Coro1a and Wip1 and for Wip1 dephosphorylation of p-Coro1a Ser426. Wip1 deletion or inhibition in neutrophils significantly upregulated the phosphorylation of Coro1a-Ser426, which activated phospholipase C and subsequently the calcium pathway, the latter of which promoted NET formation after infection or lipopolysaccharide stimulation. This study revealed Coro1a to be a novel substrate of Wip1 and showed that Wip1 is a negative regulator of NET formation during infection. These results support the potential application of Wip1 inhibitors to treat bacterial infections.
基金High-level Hospital Construction Project of GDPH(Grant No.DFJH201905)National Nature Science Foundation of China(Grant No.52271244)+2 种基金Natural Science Foundation of Guangdong Province,China(Grant No.2022A1515010202)GDPH Supporting Fund for Talent Program(Grant No.KJ012019097,KY0120220137,and KY012021462)GDPH Supporting Fund for NSFC Program(Grant No.KY012021153).
文摘The widespread use of orthopedic implants to support or replace bones is increasingly threatened by the risk of incurable bacterial infections,impenetrable microbial biofilms,and irreversible antibiotic resistance.In the past,the development of anti-infective biomaterials focused solely on direct antibacterial properties while ignoring the host’s immune response.Inspired by the clearance of infection by the innate neutrophil response and partici-pation in anti-infectious immunity of Zn ions,we report an innovative neutrophil extracellular traps(NETs)strategy,induced by biodegradable pure Zn,which achieved therapeutic efficacy toward biomaterial-related infections.Our in vitro and in vivo data showed that pure Zn was favorable for NETs formation by promoting the release of DNA fibers and granule proteins in a reactive oxygen species(ROS)-dependent manner,thereby retraining and degrading bacteria with an efficiency of up to 99.5%.Transcriptome analysis revealed that cytoskeletal rearrangement and toll-like receptor(TLR)signaling pathway were also involved in Zn-induced NETs formation.Furthermore,the in vivo results of a Staphylococcus aureus(S.aureus)-infected rat model veri-fied that pure Zn potentiated the bactericidal capability of neutrophils around implants,and promoted osseointegration in S.aureus-infected rat femurs.This antibacterial immunity concept lays a foundation for the development of other antibacterial biomaterials and holds great promise for treating orthopedic infections.
基金supported by the National Natural Science Foundation of China,(No.82072217,81772135 and U21A20370)by the Jiangsu Natural Science Foundation(No.BK20201178).
文摘Background:Inflammation is an important factor in pathological scarring.The role of neutrophils,one of the most important inflammatory cells,in scar hyperplasia remains unclear.The purpose of this article is to study the correlation between neutrophil extracellular traps(NETs)and scar hyperplasia and identify a new target for inhibiting scar hyperplasia.Methods:Neutrophils were isolated from human peripheral blood by magnetic-bead sorting.NETs in plasma and scars were detected by enzyme-linked immunosorbent assays(ELISAs),immunofluorescence and flow cytometry.Immunohistochemistry was used to assess neutrophil(CD66B)infiltration in hypertrophic scars.To observe the entry of NETs into fibroblasts we used immunofluorescence and flow cytometry.Results:We found that peripheral blood neutrophils in patients with hypertrophic scars were more likely to form NETs(p<0.05).Hypertrophic scars showed greater infiltration with neutrophils and NETs(p<0.05).NETs activate fibroblasts in vitro to promote their differentiation and migration.Inhibition of NETs with cytochalasin in wounds reduced the hyperplasia of scars in mice.We induced neutrophils to generate NETs with different stimuli in vitro and detected the proteins carried by NETs.We did not find an increase in the expression of common scarring factors[interleukin(IL)-17 and transforming growth factor-β(TGF-β),p>0.05].However,inhibiting the production of NETs or degrading DNA reduced the differentiation of fibroblasts intomyofibroblasts.In vitro,NETs were found to be mediated by Toll-like receptor 9(TLR-9)in fibroblasts and further phosphorylated nuclear factor Kappa-B(NF-κB).We found that IL-6,which is downstream of NF-κB,was increased in fibroblasts.Additionally,IL-6 uses autocrine and paracrine signaling to promote differentiation and secretion.Conclusions:Our experiments found that NETs activate fibroblasts through the TLR-9/NF-κB/IL-6 pathway,thereby providing a new target for regulating hypertrophic scars.
文摘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.
基金Natural Science Foundation ofChina(Nos.81974552,81774160)the Scientific Research Foundation of the Science and Technology Department of Sichuan Province(No.2022YFS0417).
文摘Severe acute pancreatitis(SAP)is a life-threatening acute abdominal disease with two peaks of death:the first in the early stage,characterized by systemic inflammatory response-associated organ failure;and the second in the late stage,characterized by infectious complications.Neutrophils are the main immune cells participating in the whole process of SAP.In addition to the traditional recognition of neutrophils as the origination of chemokine and cytokine cascades or phagocytosis and degranulation of pathogens,neutrophil extracellular traps(NETs)also play an important roles in inflammatory reactions.We reviewed the role of NETs in the occurrence and development of SAP and its fatal complications,including multiple organs injury,infected pancreatic necrosis,and thrombosis.This review provides novel insights into the involvement of NETs throughout the entire process of SAP,showing that targeting NETs might be a promising strategy in SAP treatment.However,precision therapeutic options targeting NETs in different situations require further investigation.
基金supported by the Distinguished Scientist grant from Shenyang Agricultural University and Liaoning Province(8804880416076)Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(CIFMS)(2019-I2M-5-042)。
文摘African trypanosomatid parasites escape host acquired immune responses through periodic antigenic variation of their surface coat.In this study,we describe a mechanism by which the parasites counteract innate immune responses.Two Tat D DNases were identified in each of Trypanosoma evansi and Trypanosoma brucei.These DNases are bivalent metal-dependent endonucleases localized in the cytoplasm and flagella of the parasites that can also be secreted by the parasites.These enzymes possess conserved functional domains and have efficient DNA hydrolysis activity.Host neutrophil extracellular traps(NETs)induced by the parasites could be hydrolyzed by native and recombinant Tat D DNases.NET disruption was prevented,and the survival rate of parasites was decreased,in the presence of the DNase inhibitor aurintricarboxylic acid.These data suggest that trypanosomes can counteract host innate immune responses by active secretion of Tat D DNases to degrade NETs.
基金supported by the National Natural Science Foundation of China(Nos.82130001,82070045)the National key Research&Development plan(No.2020YFC2003700).
文摘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.
基金supported by The Scientific Research Cultivation Project of Meizhou People’s Hospital(No.PY-C2019001).
文摘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.
