CD40-CD40L在儿童过敏性紫癜发病机制中的作用研究

目的探讨CD40-CD40L存儿童过敏性紫癜发病机制中的作用。方法研究对象为30例HSP患儿,正常对照组30例,应用流代细胞术检测其外周血单个核细胞中CD40－CD40L的表达情况,并观察实验组治疗前后CD40-CD40L的表达有无差异,结果与对照组比较,CD40L表达明妙增高,且治疗前表达高于治疗后（P〈0．05）,CD40表达增高,但与对照组及治疗前后比较差异均无显著性（P〉0．05）。结论HSP患儿外周血单个核细胞CD40L表达增高,且治疗前离于治疗后,表明其在HSP患儿免疫紊乱发病机制中可能起着重要作用。     

CD40-CD40L在儿童持续性免疫性血小板减少症发病机制中的作用研究

目的：通过检测CD40-CD40L在持续性免疫性血小板减少症（Persistent ITP）患儿外周血单个核细胞中的表达情况,以揭示其在儿童持续性ITP发病机制中的作用。方法应用流式细胞术检测20例持续性ITP患儿治疗前后及20例对照组儿童外周血单个核细胞中CD40-CD40L的表达情况,用ELISA法检测血小板抗体（PAIgG）。结果与对照组比较,CD40和CD40L治疗前后的表达均增高（P＜0.01,P＜0.05）, CD40治疗前高于治疗后（P＜0.05）,CD40L在两组的表达则差异无统计学意义（P＞0.05）;CD40、CD40L的表达与PAIgG均呈正相关（r分别为0.713、0.746,P＜0.05）。结论 CD40-CD40L共刺激信号异常可能为儿童持续性ITP发病机制之一,阻断此共刺激途径可能获得较好的治疗效果。     

系统性红斑狼疮患者外周血单个核细胞 CD40及CD40配体分子表达的研究

目的探讨CD40及CD40配体(CD40L)分子在活跃期SLE患者外周血单个核细胞(PBMC)上的表达及在SLE发病中的可能作用机制.方法采用流式细胞仪检测13例初发活跃期及13例复发活跃期SLE患者PBMC表面CD40及CD40L分子的表达.结果初发及复发活跃期SLE患者PBMC表达CD40分子(25.94±10.10)%及(27.34±12.94)%,均较正常对照组(13.99±5.26)%明显升高(P＜0.001);初发活跃期SLE患者PBMC表达CD40L分子(1.74±1.66)%较正常对照组(0.91±0.39)%亦明显升高(P＜0.05).初发与复发活跃期SLE患者之间比较PBMC表达CD40及CD40L分子无显著性差异.结论活跃期SLE患者外周血PBMC存在CD40及CD40L分子的异常表达,提示CD40及CD40L分子在SLF患者T、B细胞之间的信号传导及SLE发病机制中可能起着重要的作用.     

CD40表达及其配体血清水平的动态变化对慢加急性肝衰竭预后的评估价值

目的研究慢加急性肝衰竭(ACLF)不同病程CD40L血清水平以及外周血单个核细胞(PBMCs)CD40表达的动态变化,旨在探讨CD40L血清水平及单核细胞上CD40的表达对慢加急性肝衰竭病情的预测价值。方法采用流式细胞术(FACS)分别对慢加急性肝衰竭早期(ACLF-E)和晚期(ACLF-L)组(25例)、慢性乙型肝炎(CHB)组(28例)、肝炎肝硬化(LC)组(13例)及健康对照(HC)组(20例)的PBMCs上CD40的表达进行检测,同时血清中可溶CD40L(即sCD154)的水平采用酶联免疫吸附试验(ELISA)测定。结果与HC组比较,CHB组、LC组、ACLF-E组及ACLF-L组PBMCs的CD40表达水平呈逐渐增加趋势,ACLF-E组增加尤其明显;ACLF-E组中血清可溶性CD40L浓度也明显高于HC组、CHB组、LC组及ACLF-L组;ACLF死亡组病程早期与晚期CD40及CD40L表达的水平均高于存活组。结论血清CD40L浓度及CD40表达与ACLF病情及预后密切相关,血清CD40L水平及PBMC上CD40表达水平可以作为ACLF病情评估和预后判断的重要标志之一。     

腹主动脉瘤与CD40的关系

目的 探讨腹主动脉瘤(AAA)发病与患者血清CD40及其配体(CD40L)浓度的相关性.方法 对30例诊断明确的腹主动脉瘤患者(病例组)与26例健康人群(正常组)进行对照研究,酶联免疫吸附试验(ELISA)双抗体夹心法测定标本中CD40和CD40L水平,应用统计学独立样本t检验分析CD40/CD40L与腹主动脉瘤的关系.结果 病例组血清CD40浓度为(96.20±26.26) ng/L,高于正常组的(76.22±6.39) ng/L,两者差异有统计学意义(P＜0.05).病例组血清CD40L浓度为(746.20±215.46) ng/L,明显高于正常组的(503.07±75.32) ng/L,两者差异有统计学意义(P＜0.05).结论 AAA患者血清CD40和CD40L浓度明显高于健康人群,提示CD40/CD40L可能参与了AAA的发病.     

RNA干扰技术阻断CD40/CD40L共刺激通路对小鼠移植心存活时间的影响

目的 探讨慢病毒介导RNA干扰(RNAi)技术阻断CD40/CD40L共刺激通路对小鼠移植心存活时间的影响.方法 以针对小鼠CD40基因的RNAi慢病毒载体在体外感染供者骨髓来源的树突状细胞(DC),制备低表达CD40的耐受性DC(Tol-DC).荧光实时定量聚合酶链反应及流式细胞术检测DC感染前后CD40 mRNA及DC表面抗原CD40、CD11c和MHCⅡ的表达.建立小鼠异位腹腔心脏移植模型.在小鼠异位心脏移植前7 d,经静脉给受者输注体外制备的低表达CD40的Tol-EC(慢病毒感染DC注射组),并设置单纯移植对照组和未感染DC注射组作为对照.观察各组移植心的存活时间,评定各组术后第7天移植心排斥反应的病理分级.结果 CD40-RNAi慢病毒载体在体外感染DC 48 h后,CD40 mRNA表达明显受到抑制,抑制率为80.9%;CD40表达明显下降,由(74.37±4.08)%降至(40.07±4.03)%(P＜0.05).单纯移植对照组、未感染DC注射组和慢病毒感染DC注射组移植心存活时间分别为:(8±2)d、(9±1)d和(14±4)d,慢病毒感染DC注射组移植心存活时间明显延长,并且移植心排斥反应病理分级显著降低,差异有统计学意义(P＜0.05).结论 阻断CD40/C40L共刺激通路可抑制异系T淋巴细胞的活化,从而抑制急性排斥反应,延长小鼠移植心的存活时间.     

胃癌根治术病人围术期异体输血后外周血单核细胞CD40L表达的变化

目的 研究胃癌根治术病人围手术期异体输血外周血单核细胞(PBMCs)白细胞分化抗原40配体(CD40L)表达的变化。方法 胃癌根治术病人30例,随机分为3组,每组10例。A组围术期不输血,B组围术期输入去白细胞的全血,C组围术期输入异体全血。另选10例健康人作为对照。分别在手术前、术后2、5、10 d采外周静脉血5 ml,用Ficoll分离液梯度离心法分离出PBMCs和血浆,将PBMCs置于自身血浆环境中,并在植物血凝素(PHA,20 mg/L)的刺激下进行培养,48 h后收获细胞,用流式细胞术检测CD40L表达。结果 健康人外周血未受PHA刺激时检测不到CD40L的表达,经PHA刺激后CD40L 细胞占CD4 T细胞的百分数为1.7％±0.4％,与三组胃癌病人术前比较差异无显著性(P>0.05)。与术前比较,B组术后2 d PBMCs CD40L表达升高(P<0.05),C组术后各时点升高(P<0.05);与A组比较,B组术后2 d升高(P<0.05),C组术后各时点升高(P<0.05);与B组比较,C组术后各时点升高(P<0.05)。结论 围手术期异体输血可造成免疫抑制,输异体血后CD40L表达增加,且输全血比输去白细胞的全血更明显。围手术期成分输血优于输注全血。     

CD40作为脊柱结核靶向治疗靶标分子的实验研究

目的:通过对不同感染复数结核分枝杆菌侵染的正常人成骨细胞表面CD40分子差异表达的实验研究,探讨CD40作为脊柱结核分子靶向治疗的靶标分子的可行性。方法:将冷冻保存的正常人成骨细胞按照美国模式菌种收集中心(American Type Culture Collection,ATCC)的说明进行复苏和培养,传代至3代冻存备用;之后选择Middlebrooke7H9液体培养基对荧光结核分枝杆菌(H37Ra-GFP)进行培养,培养至对数中期备用。把传代后的人成骨细胞随机分为A、B、C、D四组,A组为对照组,是未被结核分枝杆菌侵染的人成骨细胞组;B、C、D三组均为实验组,分别是被感染复数(multiplicity of infection,MOI)为1∶1000、1∶100、1∶10浓度的结核分枝杆菌侵染的人成骨细胞组。然后采用实时定量PCR与蛋白免疫印迹(Western Blot,WB)的方法,分别检测不同感染复数结核分枝杆菌诱导人成骨细胞中CD40 mRNA的表达变化及成骨细胞表面CD40分子的表达变化。结果:传代后的人成骨细胞经荧光结核分枝杆菌侵染后,观察发现各组细胞感染程度良好。A组实时定量PCR反应结果表现为人成骨细胞中存在CD40 mRNA的表达;A (1.0337±0.0715)、B (1.4083±0.1145)、C(1.7172±0.1294)、D(2.0378±0.1573)四组之间的表达存在差异(F=74.005,P0.05);B、C、D三组分别与A组相比时,均存在差异(P0.05),表现为结核分枝杆菌侵染组B、C、D三组成骨细胞中CD40 mRNA的表达均高于未侵染组A组;B、C、D三组,两两比较时,均存在差异(P0.05),表现为从B组到D组成骨细胞中CD40mRNA的表达依次上调。而通过蛋白免疫印迹法分析成骨细胞表面CD40分子的表达结果发现与上述m RNA表达上调的结果完全吻合。结论:结核分枝杆菌侵染人成骨细胞后可诱导成骨细胞中CD40 mRNA以及成骨细胞表面CD40分子的表达增多,并且感染复数越高,细胞表面CD40分子的表达越多。而CD40分子可与其所对应的核酸适体特异结合,这就为使用CD40分子作为靶标分子,对脊柱结核进行靶向治疗提供了理论基础。     

DCs单抗对大鼠肾移植后排斥反应时CD40/CD40L表达的影响

目的：观察大鼠树突状细胞（DCs)单抗单独或与甲泼尼龙（MP）联合应用对移植后排斥反应的影响，并结合检测大鼠移植肾CD40／CD40L表达水平，探讨其抗排斥的作用机制，方法：实验共分为5组，同系移植组，不用药实验对照组；MP治疗组：DCs单抗治疗组；DCs单抗＋MP治疗组，利用免疫组织化学方法检测移植肾内CD40／CD40L表达，每一样本采用计算机图像分析定量测定。结果：大鼠DCs单抗单独或与MP联合治疗组受体鼠存活时间较不用药对照组显著延长（P＜0．01），其中DCs单抗＋MP治疗组尤为明显，术后7d，不用药实验对照组移植肾脏组织CD40／CD40L，表达水平显著高于其它各组，DCs单抗＋MP治疗组表达水平显著低于MP组及DCs单抗组（P＜0．01），同系移植组表达水平最低。结论：单独应用DCs单抗或与MP联合应用均显著延长大鼠肾移植存活期，干扰CD40／CD40L共刺激通路信号传导可能是其抗排斥机制之一。     

骶骨脊索瘤CD40、PCNA、CD31表达及其与肿瘤复发的相关性研究

[目的]研究骶骨脊索瘤中CD40、PCNA、CD31的表达水平及其与脊索瘤复发的相关性。[方法]采用EnVi-sionTM免疫组化技术检测28例骶骨脊索瘤组织、9例正常胚胎脊索组织中的CD40和PCNA的表达,并计数CD31标记的肿瘤组织微血管密度(MVD)。[结果]①CD40、PCNA在骶骨脊索瘤中的强阳性表达率分别为66.1%、64.3%,明显高于正常胚胎脊索组织。两者之间的差异有统计学意义(P<0.05);骶骨脊索瘤中CD31标记的微血管密度(24.26±18.68)/mm2,正常胚胎脊索组织微血管密度值为(4.63±2.19)/mm2;差异有统计学意义(P<0.05);②28例骶骨脊索瘤,其中复发组14例,非复发组14例,两组间CD40阳性表达率分别为14.29%、85.71%;PCNA阳性表达率分别为92.86%、50.00%;CD31标记的MVD值分别为(30.66±23.75)/mm2、(17.88±8.52)/mm2;均有统计学差异(P<0.05);③CD40、PCNA表达及CD31标记的MVD值与患者的年龄、性别、肿瘤大小无统计学相关性;④PCNA阳性表达的骶骨脊索瘤组织中MVD值为(28....     

血清CD40和CD40L的检测在胃癌病人中的表达

CD40分子是与T细胞和B细胞功能有关的一种表面抗原,属于肿瘤坏死因子受体（Tumor Necrosis Factor Receptor,TNFR）超家族成员。作为CD40的配体,CD40L也称gp39、肿瘤坏死因子相关激活蛋白（TNF associated activation protein,TRAP）和T细胞-B细胞活化分子（T cell—Bcell-activating molecule,T—BAM）。CD40-CD40L是免疫细胞间重要的信号传导通路,在抗原呈递细胞识别靶抗原,     

CD40 ligand increases expression of its receptor CD40 in human coronary artery endothelial cells

BACKGROUND: Recently, CD40 ligand (CD40L) and its receptor CD40 have been implicated in atherosclerosis. Clinical data showed that elevated CD40L levels are associated with a high risk of cardiovascular events. The aim of this study was to investigate whether CD40L could affect the expression of its membrane receptor CD40 as a feedback mechanism by which CD40L could enhance its functions in human coronary artery endothelial cells (HCAECs). METHODS: The HCAECs were treated with human soluble CD40L, and the messenger RNA (mRNA) and protein levels of CD40 were determined by real-time polymerase chain reaction and Western blot analysis, respectively. The specific effect of CD40L was confirmed by a blocking experiment with antibody against CD40L. Involvements of oxidative stress and mitogen-activated protein kinases (MAPKs) were also studied with antioxidant seleno-L-methionine (SeMet) and MAPK inhibitors such as extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor. RESULTS: When HCAECs were cultured with CD40L (5 microg/mL) for 24 hours, CD40 mRNA levels were increased by 79% compared with controls (P < .05). Similarly, Western blot analysis showed an 80% increase in CD40 protein levels (P < .05). The CD40L-induced increase in CD40 mRNA levels were blocked specifically by anti-CD40L antibody. Antioxidant SeMet and specific ERK1/2 inhibitor (PD98059) also effectively blocked CD40L-induced CD40 mRNA increase. CONCLUSIONS: These data demonstrate that clinically relevant concentration of CD40L increased the expression of its receptor CD40 in HCAECs. The CD40L-induced upregulation of CD40 may be mediated by oxidative stress and ERK1/2 activation. This study suggests a new mechanism by which CD40L could enhance its biologic functions in the vascular system and contribute to endothelial dysfunction and vascular disease.     

Targeting LFA-1 Synergizes with CD40/CD40L Blockade for Suppression of Both CD4-Dependent and CD8-Dependent Rejection

Allogeneic hepatocytes elicit CD4-dependent and (CD4-independent) CD8+ T-cell-initiated graft rejection. The (CD4-independent) CD8+ T-cell pathway is resistant to immunosuppressive strategies that readily and indefinitely suppress CD4+ T-cell-dependent rejection responses. Consequently, successful immunoregulation of hepatocyte-initiated immune responses requires a strategy which regulates both CD4-dependent and CD8-dependent rejection responses. Interference with CD40/CD40 ligand (CD40L) costimulation only transiently suppresses CD4- and CD8-dependent hepatocyte rejection. Interference with CD28/B7 costimulation transiently suppresses CD4-dependent hepatocyte rejection, but is ineffective for suppression of CD8-dependent hepatocyte rejection. To date, hepatocyte survival > 60 days post-transplant has not been achieved by any immunotherapeutic strategy. In the current study, we evaluated a novel immunosuppressive strategy which targets both LFA-1 and CD40L-mediated signals. Targeting LFA-1 suppressed (CD4-independent) CD8+ T-cell-initiated hepatocyte rejection such that allogeneic hepatocyte survival > 60 days was achieved in 70% of CD4 KO mice. Targeting both LFA-1-mediated signals and CD40/CD40L costimulation resulted in synergistic effects, such that hepatocellular survival > 60 days was achieved in 100% of C57BL/6 mice (which have both CD4- and CD8-dependent T-cell pathways available).     

Neutralizing IL-7 Promotes Long-Term Allograft Survival Induced by CD40/CD40L Costimulatory Blockade

Memory T cells are somewhat resistant to immunosuppresion. They therefore pose a threat to inducing long‐term allograft survival. IL‐7 is essential for memory T‐cell generation. Here, we investigated whether neutralizing IL‐7 promotes allograft survival. We found that neutralizing IL‐7 alone did not significantly prolong allograft survival. However, blocking both IL‐7 and CD154 signaling synergistically prolonged allograft survival. In contrast, neutralizing IL‐2 failed to further prolong allograft survival induced by CD40/CD154 costimulatory blockade. Allospecific memory CD8+ T‐cell generation was severely impaired under the treatment of anti‐IL‐7 plus anti‐CD154 Ab while administering recombinant IL‐7 enhanced CD8+ memory generation even under donor‐specific transfusion plus anti‐CD154 Ab treatment. Neutralizing IL‐7, but not IL‐2, together with blocking CD154 synergistically suppressed the proliferation of naïve/effector CD8+ T cells infiltrating grafts. Nevertheless, neutralizing IL‐7 did not alter regulatory T‐cell generation while neutralizing IL‐2 suppressed their generation. Hence, targeting IL‐7 represents a new strategy to prolong allograft survival by acting on both naïve and memory T cells. Long‐term allograft survival may be achieved by neutralizing IL‐7 plus CD40/CD154 blockade, since CD40/CD154 costimulatory blockade prevents acute rejection while neutralizing IL‐7 suppresses the generation of memory T cells that persist and mediate late or chronic rejection.     

阻断OX40和CD40协同共刺激信号延长小鼠胰岛移植物存活时间

目的 研究阻断OX40/OX40L和CD40/CD154L协同共刺激通路对小鼠胰岛移植物存活的影响及其机制.方法 以DBA/2小鼠为供者,C57BL/6小鼠为受者,制作胰岛移植模型.受鼠分为4组.(1)对照组,注射IgG; (2)抗OX40组,注射抗OX40L单克隆抗体;(3)抗CD154组,注射抗CD154单克隆抗体;(4)联合治疗组,注射抗OX40L单克隆抗体和抗CD1 54单克隆抗体.记录各组胰岛移植物平均存活时间(MST).将CD154敲除小鼠处死,取其脾脏T淋巴细胞,体外检测活化T淋巴细胞表面OX40的表达;在活化T淋巴细胞中加入不同浓度的抗OX40L单克隆抗体,体外检测T淋巴细胞增殖情况.结果 对照组胰岛移植物MST为19 d,抗CD154组胰岛移植物MST为48 d(P＜0.05);抗OX40组胰岛移植物MST为22 d,与前两组相比较,差异无统计学意义(P＞0.05);联合治疗组胰岛移植物MST＞ 150 d,高于另外3组(P＜0.05).66％的胞表达OX40,较初始T淋巴细胞的表达率高(2％,P＜0.05);加入抗OX40L单克隆抗体后,T淋巴细胞增殖受抑制且呈剂量依赖性.结论 阻断OX40/OX40L和CD40/CD154L双通路可诱导小鼠胰岛移植物长期存活, 其发挥作用的关键机制是抑制了T淋巴细胞的增殖.     

Analysis of the CD40/CD40L role in the sustenance of alloreactive antibody production

CD40 ligand (CD40L) is important for T/B lymphocyte interaction. To understand the cellular basis of humoral allosensitization we, therefore: (1) measured CD40L protein and gene expression in sensitized and non-sensitized uremic unactivated peripheral CD4+ T lymphocytes; (2) studied the impact of blocking the CD40/CD40L pathway on alloreactive antibody (allo-Ab) production by engrafted sensitized PBLs into severe combined immunodeficient (SCID) mice after in vitro preactivation with IL2/LPs/HLA class II allopeptides and adjuvants as a potent stimulus to produce allo-Ab (Shoker et al. Transplantation 1999;68;1188); and (3) studied the modifying effect of CD40/CD40L blockade on T helper type I and II cytokine gene expression in the respective mice spleen. The CD40L protein was measured by flow cytometry and the gene expression was measured by quantitative RT-PCR. Alloreactive antibodies (alo-Abs) produced by sensitized PBLs engrafted into SCID mice with and without blockade of the CD40 receptor were measured by the PRA-STAT ELISA method. The modifying effects of CD40 blocking on allo-Ab production and cytokine gene expression by the engrafted cells measured by RT-PCR were then compared. There was no detectable CD40L protein expression in either the uremic or the control groups. The CD40L gene expression of 0.04 +/- 0.02 attomoles (aM) in the sensitized group was significantly higher than in the non-sensitized patients (0.009 +/- 0.007 aM, P < 0.0001) or the control CD4+ T cells (0.016 +/- 0.004 aM, P < 0.001). Blockade of the CD40 receptor abrogated the production of allo-Ab antibodies by the engrafted sensitized cells in 60% of the tested mice (n = 10); decreased the mean +/- S.D. optic density of allo-Ab to 0.1 +/- 0.13 and the mean +/- S.D. PRA to 12 + 16). In the presence of the control Ab, allo-Ab production in SCID sera was present in 100% of the 10 SCID mice tested; the mean +/- S.D. PRA was 75 +/- 20, and the mean + S.D. OD activity was 0.412 +/- 0.17. All cytokine genes were, otherwise, expressed in the presence or absence of CD40 blockade. The results suggest a potential role of an enhanced CD40/CD40L interaction in the sustenance of alloreactive antibody production without significant deviation to T helper-like I or II responses. Blocking the CD40/CD40L pathway may have a potential therapeutic benefit to treat sensitized uremic patients.     

CD40 expression on graft infiltrates and parenchymal CD154 (CD40L) induction in human chronic renal allograft rejection

BACKGROUND: CD40-CD154 (CD40L) costimulatory signaling plays a pivotal role in the effector mechanisms of transplant graft rejection. In animal models, CD40-CD154 blockade induces long-term graft acceptance concurrent with an absence of chronic rejection (CR) lesions. Given the critical importance of CD40-CD154 interactions in the development of chronic transplant allograft rejection, the relevance of in situ CD40 and CD154 expression was assessed in human chronic renal allograft rejection. METHODS: The expression of CD40, CD154, CD68, and T-cell receptor (TCR)alpha/beta was analyzed by immunohistochemistry. Serial cryostat sections of snap-frozen core renal allograft biopsies were obtained from 30 renal transplant patients. Biopsy specimens received diagnoses of CR (N = 23) according to the Banff classification and were compared with controls (N = 7) consisting of stable allografts and normal kidney tissue. RESULTS: Striking CD40 staining of graft cellular infiltrates (P = 0.016) was observed in renal allografts with CR compared with controls. The CD40+ cellular infiltrates in CR were predominantly TCR alpha/beta + T cells and some CD68+ macrophages. These findings were contrasted by the low-level CD40 expression detected in glomeruli and tubules of CR and controls. However, glomerular induction of CD154 was observed in CR allografts (P = 0.028) as compared with controls. CD154 immunoreactivity was demonstrated on glomerular endothelial, epithelial, and mesangial cells. Moderate CD154 expression was detected on tubular epithelial cells, and only weak CD154 immunoreactivity was observed on the infiltrates in isolated CR cases. CONCLUSION: In human chronic renal allograft rejection, CD40 is expressed on graft-infiltrating cells of the T cell and macrophage compartments. CD154 expression is induced on glomerular and tubular epithelial cells during CR, demonstrating another novel source of CD154 expression. The data substantiate the potential contributory role of an interaction between CD40+ graft-destructive effector T cells and macrophages with CD154+ renal allograft parenchymal cells in the development of chronic renal allograft rejection.