简介:AIMToinvestigatetheroleofthecomplement5a(C5a)/C5areceptor(C5aR)pathwayinthepathogenesisofacuteliverfailure(ALF)inamousemodel.METHODSBALB/cmicewererandomlyassignedtodifferentgroups,andintraperitonealinjectionsoflipopolysaccharide(LPS)/D-galactosamine(D-GalN)(600mg/kgand10μg/kg)wereusedtoinduceALF.TheKaplanMeiermethodwasusedforsurvivalanalysis.Serumalanineaminotransferase(ALT)levels,atdifferenttimepointswithina1-wkperiod,weredetectedwithabiochemistryanalyzer.Pathologicalexaminationoflivertissuewasperformed36hafterALFinduction.Serumcomplement5(C5),C5a,tumornecrosisfactor-α(TNF-α),interleukin(IL)-1β,IL-6,high-mobilitygroupproteinB1(HMGB1)andsphingosine-1-phosphatelevelsweredetectedbyenzyme-linkedimmunosorbantassay.Hepaticmorphologicalchangesat36hafterALFinductionwereassessedbyhematoxylinandeosinstaining.ExpressionofC5aR,sphingosinekinase1(SphK1),p38-MAPKandp-p38-MAPKinlivertissue,peripheralbloodmononuclearcells(PBMCs)andperitonealexudativemacrophages(PEMs)ofmiceorRAW264.7cellswasanalyzedbywesternblotting.C5aRmRNAlevelsweredetectedbyquantitativereal-timePCR.RESULTSActivationofC5andup-regulationofC5aRwereobservedinlivertissueandPBMCsofmicewithALF.BlockadeofC5aRwithaC5aRantagonist(C5aRaC5aRa)significantlyreducedthelevelsofserumALT,inflammatorycytokines(TNF-α,IL-1βandIL-6)andHMGB1,aswellasthelivertissuedamage,butincreasedthesurvivalrates(P<0.01forall).BlockadeofC5aRdecreasedSphK1expressioninbothlivertissueandPBMCssignificantlyat0.5hafterALFinduction.C5aRapretreatmentsignificantlydownregulatedthephosphorylationofp38-MAPKinlivertissuesofALFmiceandC5astimulatedPEMsorRAW264.7cells.Moreover,inhibitionofp38-MAPKactivitywithSB203580reducedSphK1proteinproductionsignificantlyinPEMsafterC5astimulation.CONCLUSIONTheC5a/C5aRpath
简介:摘要目的建立咪喹莫特(imiquimod,IMQ)诱导小鼠慢性银屑病样皮炎模型,探讨补体C5a/C5aR1通路在该病理过程中的作用及机制。方法IMQ涂抹(每2天1次,共8次)小鼠背部皮肤建立慢性银屑病样皮炎模型。比较BALB/c(C5aR1+/+)及C5aR1基因敲除(C5aR1-/-)小鼠皮炎程度及病理改变;免疫组化(immuohistochemistry, IHC)检测皮损组织表皮细胞增殖(Ki67)、角蛋白K6/K14表达及中性粒细胞浸润(Ly-6G)情况;实时荧光定量PCR(qPCR)检测皮损组织角蛋白K6/K14及炎症因子表达。流式细胞术检测皮损局部炎症细胞浸润及IL-17A应答。结果IMQ可诱导银屑病皮炎典型表型,如银屑、红斑及皮肤增厚。HE染色提示表皮角质细胞异常增殖、棘皮症、微脓肿、炎症细胞浸润及真皮毛细血管异常增生。与C5aR1+/+小鼠比较,C5aR1-/-小鼠皮炎表型明显减轻,角质细胞异常增殖、角蛋白K6/K14表达及中性粒细胞浸润显著降低;qRCR检测同样发现C5aR1-/-小鼠角蛋白K6/K14、炎症因子(IFN-γ、MIP-1α、IL-1β和TNF-α)及IL-17应答相关细胞因子(IL-6、IL-17A和IL-23)表达明显下调。此外,C5aR1-/-小鼠皮损组织白细胞(CD45)、T细胞(CD3)及IL-17A+γδTCR+T等浸润显著减少;C5aR1-/-小鼠腋窝引流淋巴结及IL-17A+细胞、IL-17A+ CD3+T和IL-17A+ γδTCR+ T比例显著降低。结论本研究成功建立了小鼠慢性银屑病样皮炎模型,补体C5a/C5aR1通路可能激活IL-17产生细胞发挥作用,阻断该通路有望成为银屑病治疗的新策略。
简介:摘要目的探讨脓毒症发病机制中补体C5a参与免疫调节的机制。方法选择SPF级雄性C57BL/6J小鼠,按照随机数字表法分为假手术组(Sham组)、盲肠结扎穿孔术(CLP)模型组(CLP组)和CLP+抗C5a单克隆抗体干预组(CLP+anti-C5a组),每组20只。构建CLP诱发脓毒症模型;Sham组只开腹不进行结扎穿孔。CLP+anti-C5a组于制模后立即腹腔注射抗C5a单克隆抗体0.15 mg干预;Sham组和CLP组给予等量生理盐水。采用Kaplan-Meier法对各组小鼠进行累积生存分析;采用酶联免疫吸附试验(ELISA)检测术后24、48、72 h外周血血清肿瘤坏死因子-α(TNF-α)、白细胞介素(IL-12、IL-4)及γ-干扰素(IFN-γ)水平;采用免疫组化法观察术后48 h肺组织及肾组织C5a受体(C5aR)表达;采用流式细胞仪检测术后48 h脾脏单个核细胞中树突细胞(DC)、调节性T细胞(Treg)和辅助性T细胞17(Th17)的比例。结果CLP组小鼠7 d累积生存率较Sham组明显下降(30.00%比100.00%;Log-Rank检验:χ2=47.470,P<0.001);血清炎性因子TNF-α、IL-12及IL-4水平于术后24 h先反应性升高,48 h明显下降,随后于72 h逐渐升高,而IFN-γ水平于术后24 h开始持续升高至72 h;免疫组化显示,CLP组术后48 h肺组织和肾组织内皮细胞中均有大量C5aR表达;与Sham组比较,脾脏单个核细胞中DC比例〔(1.80±0.30)%比(6.90±1.20)%,P<0.05〕及Treg比例〔(0.38±0.02)%比(4.00±0.50)%,P<0.05〕均明显下降,Th17比例明显升高〔(0.83±0.08)%比(0.32±0.03)%,P<0.05〕,提示免疫细胞比例失衡,免疫功能紊乱。给予抗C5a单克隆抗体干预后,小鼠7 d累积生存率较CLP组明显升高(54.54%比30.00%;Log-Rank检验:χ2=28.090,P<0.001);血清TNF-α、IL-12和IFN-γ水平进一步升高,而IL-4水平明显下降;肺组织及肾组织C5aR表达较CLP组显著减少;脾脏中成熟DC比例〔(5.10±1.20)%比(1.80±0.30)%,P<0.05〕和Treg比例〔(2.58±0.05)%比(0.38±0.02)%,P<0.05〕较CLP组明显升高,Th17比例较CLP组明显降低〔(0.54±0.05)%比(0.83±0.08)%,P<0.05〕。结论初步判断抗C5a单克隆抗体可能通过改善脾脏中成熟DC及T细胞极化状态进而改善脓毒症预后,C5a在脓毒症细胞免疫调节中发挥重要作用。
简介:Tris)(η5-cyclopentadienyl-μ-carbonyl-iron)-μ3-nitrosylclusterwasobtainedfromthereactionofcyclopentadienyldicarbonylirondimerwithnitrogenmonoxideinxylene.Theclusterwascharacterizedbyelementalanalyses,IR,MSand1HNMR.Thecrystalstructureof[(η5-C5H5)(μ-CO)Fe]3(μ3-NO).C4H8OwasdeterminedbyX-raydiffractionanalysis.ItcrystallizesintheorthorhombicspacegroupPnma,a=9.053(2),6=10.545(2),c=22.525(4)A,V=2150.3(7)A3,Z=4,Dc=1.68g.cm-3;structuresolutionandrefinementbasedon1141reflectionswithI>3.0(I)(MoKa,A=0.71073A)convergedatR=0.0540.Theinfraredabsorptionbandat1325cm-1oftheμ3-NOinthecluster,whichisredshifted,showsthatμ3-NOisactivated.