T细胞活化的新共刺激途径ICOS—B7h

近年来发现的共刺激途径ICOS-B7h在免疫应答中的作用正越来越受到重视。本文拟就ICOS-B7h的结构、表达等生物学特性及功能意义作一综述。     

两株鼠抗人GL50单克隆抗体的制备及其生物学特性的初步研究

目的　研制鼠抗人GL5 0分子单克隆抗体并对其生物学特性进行初步研究。方法　以天然高表达人GL5 0分子的Daudi细胞为免疫原 ,人GL5 0 L92 9转基因细胞为目的单克隆抗体(McAb)的筛选细胞 ,采用B淋巴细胞杂交瘤技术 ,获得分泌特异性鼠抗人GL5 0分子McAb的杂交瘤细胞株 ;免疫荧光标记和流式细胞术分析McAb识别GL5 0的表达 ;Westernblot检测抗体对特异性细胞膜蛋白的识别 ;台盼蓝 (Trypanblue)染色细胞计数法和MTT法检测McAb对Daudi细胞体外生长的抑制作用 ;3 H TdR法检测抗体对GL5 0 L转基因细胞介导的活化T细胞体外增殖的效应。结果　成功制备 2株分泌特异性抗人GL5 0抗体的杂交瘤细胞株 12B11和 11C4 ;两者皆为IgG2a亚型 ;腹水效价皆在 1∶10 0 0以上 ;12B11、11C4特异性地识别GL5 0分子。 11C4McAb可以明显抑制Daudi细胞在体外的生长 ,并可抑制GL5 0 L转基因细胞介导的活化T淋巴细胞的体外增殖效应。结论　成功获得了 2株特异性鼠抗人GL5 0抗体 ,其中 11C4McAb具有诱导表达GL5 0分子的B淋巴瘤细胞Daudi的体外生长抑制作用 ;在T淋巴细胞体外增殖反应中发挥了重要的调节作用。     

ICOS/ICOSL在类风湿关节炎患者外周血淋巴细胞的表达及临床意义

目的:检测初发类风湿关节炎(Rheumatoid arthritis,RA)患者外周血淋巴细胞表面共刺激分子ICOS和ICOSL的表达,并探讨其临床意义。方法:采用流式细胞术和RT-PCR的方法,检测85例初发RA患者和50例健康对照(Healthy control,HC)外周血CD4+T细胞表面ICOS及CD14+单核细胞和CD19+B细胞表面ICOSL的表达,比较15例初诊RA患者治疗前后ICOS和ICOSL表达水平变化,分析其临床意义。结果:RA患者外周血中ICOS/ICOSL的mRNA的表达水平显著高于HC。RA患者外周血CD4+T细胞表面ICOS表达显著增高[(7.08±4.72)%vs(3.01±1.39)%,P0.0001]。RA患者外周血中CD14+单核细胞[(5.77±3.45)%vs(3.64±1.43)%,P0.05]和CD19+B细胞[(5.78±4.52)%vs(3.97±1.63)%,P0.05]表面ICOSL的表达均高于HC。活动期的RA患者外周血单核细胞和B细胞表面的ICOSL表达高于非活动期患者[(5.45±3.50)%vs(4.04±1.55)%,P=0.036]、[(6.59±5.74)%vs(5.63±4.30)%,P=0.016],治疗后CD4+T细胞表面ICOS的表达及CD14+单核细胞和CD19+B细胞表面ICOSL的表达均显著下降[(3.33±0.31)%vs(5.56±1.11)%,P=0.076]、[(5.12±1.23)%vs(9.99±2.02)%,P=0.045]、[(3.74±0.57)%vs(8.62±1.77)%,P=0.011]。结论:RA患者外周血单个核细胞表面ICOS和ICOSL异常高表达,且与疾病活动度和临床疗效密切相关。提示ICOS/ICOSL信号通路可能参与RA免疫病理进程。     

ICOS 在健康人外周血调节性T 细胞上的生物学特征初探

目的:研究ICOS 在健康人外周血Treg 离体培养中的作用,了解mTOR 对离体培养Treg ICOS 表达的调控。方法:MACS 分选Treg 后经anti-CD3+anti-CD28 磁珠刺激后第3、7 天流式检测Treg 表面ICOS 表达情况;anti-CD3+anti-CD28抗体或anti-CD3+ICOSL-Fc 刺激3 d,流式检测Treg ICOS 表达情况;雷帕霉素处理离体培养Treg,流式分析其对Treg ICOS 表达作用。CFSE 标记人PBMC 细胞,并与离体培养Treg 混合培养,流式检测Treg 的接触抑制活性。结果:anti-CD3+anti-CD28磁珠刺激Treg 3 d,ICOS+ Treg 中活、死细胞的比例分别为(92.00依2.69)%和(2.20依0.56)%,在ICOS- Treg 中比例为(90.30±3.53)%和(1.77±0.78)%,两者无显著差异;培养第7 天,ICOS+ Treg 细胞比例从第3 天(40.20±1.83)% 降至(11.60±1.10)%;anti-CD3 +ICOSL-FC 刺激Treg 3 d 后,ICOS MFI 为(403.30依74.42),anti-CD3+anti-CD28 刺激组为(2 410.0±746.4),anti-CD3+ICOSL-FC 刺激后Treg ICOS 表达相比anti-CD3+anti-CD28 组显著下降;雷帕霉素处理离体培养Treg 细胞3 d 后,ICOS 表达下调。此外,雷帕霉素处理的离体培养Treg 均能有效抑制PBMC 中Tcon 的分裂增殖。结论:ICOS 表达高低对人外周血Treg 存活率影响无显著差异,mTOR 信号并非调控人Treg 离体培养ICOS 表达的唯一因素,CD28 协同信号对调控离体培养人Treg 。表达比ICOSL 信号更为重要,雷帕霉素处理的离体培养人Treg 仍具有细胞接触抑制活性。     

T细胞活化的新共刺激途径ICOS-B7h

近年来发现的共刺激途径ICOS B7h在免疫应答中的作用正越来越受到重视。本文拟就ICOS B7h的结构、表达等生物学特性及功能意义作一综述。     

086 T细胞活化的新共刺激途径ICOS-B7h

近年来发现的共刺激途径ICOS-B7h在免疫应答中的作用正越来越受到重视.本文拟就ICOS-B7h的结构、表达等生物学特性及功能意义作一综述.     

T细胞共刺激分子在重症肌无力发病机制中的作用

重症肌无力（MG）是由乙酰胆碱受体抗体介导的细胞免疫依赖性和补体参与的神经肌接头部位的自身免疫性疾病,免疫应答异常是其发病本质。近年研究发现CD28：CTLA4／87和CD154／CD40是最重要的共刺激分子,对T和B淋巴细胞的增殖、活化、抗体和细胞因子的分泌均具有重要作用,其对重症肌无力的发生和发展也具有十分关键的作用。     

ICOS共刺激途径中MAPK家族信号分子对活动期SLE患者T细胞增殖及细胞因子分泌的作用

目的研究可诱导共刺激分子（ICOS）共刺激途径中丝裂原活化蛋白激酶（MAPK）家族信号分子对活动期系统性红斑狼疮（SLE）患者T细胞增殖及细胞因子分泌的作用。方法体外分离纯化活动期SLE患者和正常人外周总T细胞、CD4^＋和CD8^＋T细胞，予以抗CD3／抗ICOS刺激，通过Western blot检测信号分子的活化水平，ELISA检测培养上清细胞因子表达，^3H—TdR法测定细胞的增殖水平。结果活动期SLE病人CD4^＋或CD8^＋T细胞经ICOS共刺激后，胞外信号调节激酶（ERK）的活化水平明显低于正常人，CD4^＋或总T细胞分泌IL-2明显低于正常人，PD98059抑制ERK活化可致细胞增殖水平下降与IL-2分泌减少，SB-203580抑制p38MAPK活化可致IL-10分泌减少，细胞因子IL-2能明显促进T细胞的增殖水平。结论活动期SLE患者ICOS共刺激T细胞增殖功能降低与其ERK信号活化障碍所致的IL-2分泌减少密切相关，MAPK家族信号分子在ICOS共刺激不同T细胞亚群增殖与细胞因子分泌中具有不同的作用。     

ICOS/ICOSL逆向信号诱导成熟过程中树突状细胞特异性分泌TGF-β1

目的:分析可诱导共刺激分子(ICOS)能否向成熟过程中树突状细胞(DCs)传递逆向信号及其对DCs功能的影响。方法:取小鼠骨髓细胞,体外诱导培养、纯化第5天不成熟DCs,以ICOSIg或对照IgG加LPS或CpG处理后,流式细胞仪检测DCs表型分子、吞噬功能及胞内细胞因子改变;以ELISA检测培养上清细胞因子变化;以[3H]-TdR掺入法探讨DCs抗原递呈功能。结果:与IgG对照组相比,ICOSIg联合LPS或CpG处理组DCs分泌TGF-β1的表达明显升高;ICOSIg作用于成熟过程中DCs,其吞噬功能与对照IgG相比近似或略有增强,但其抗原递呈功能受到部分抑制,可引起T细胞中IL-2、IL-10明显升高。结论:ICOS作用于成熟过程中的DCs后,促进DCs特异性分泌TGF-β1、部分抑制了DCs的抗原递呈功能,其机制可能是诱导了产IL-10 CD4+T细胞的生成;这种反向信号在不同机制诱导DCs成熟的过程中均可能存在。     

CD40-CD40L共刺激途径在体液免疫和细胞免疫中的作用

CD40与CD40配体(CD40L)是体内炎症和免疫反应系统的一对共同刺激分子,参与机体的体液免疫和细胞免疫反应.CD40-CD40L共刺激途径能促进T细胞活化并放大T淋巴细胞依赖的免疫应答,是产生记忆性CD8+T细胞的基础,能够促进CD8+T细胞的扩增和多能性,在CD4+T细胞分化的过程中起重要作用,介导更强的抗肿瘤效应和杀伤靶细胞的能力.CD40-CD40L共刺激途径参与T淋巴细胞依赖的B淋巴细胞应答过程、生发中心的形成、长期记忆性R细胞的产生、抗体的产生及抗体类别转换,并可诱导和扩增CD4+ CD25+ Treg细胞.CD40-CD40L共刺激途径在多种疾病的发生、发展中起作用,有广阔的临床应用前景.     

Asymmetry in Cerebral Hemispheres and Thymus Lobes during Realization of Humoral Immune Response in Mice

We studied the role of functional asymmetry in mouse brain and thymus in the realization of humoral immune response. We concluded that not only nervous system asymmetry, but also immune system asymmetry and the relationship between cerebral hemispheres and cells of the right and left thymus lobes play an important role in the regulation of immune response.     

5—羟色胺对大鼠体液免疫应答的影响

本研究用神经药理学方法改变大鼠全身、中枢或外周5-羟色胺(5-HT)的含量,并使用5-HT受体的拮抗剂,观察初次体液免疫应答有无变化,从而探讨5-HT调节体液免疫功能的作用途径和作用机制。结果发现:大鼠腹腔注射5-羟色氨酸(5-HTP)后,体液免疫应答减弱。腹腔注射对氯苯丙氨酸(PCPA)后,免疫应答增强。用去甲丙味嗪(DMI)预处理,然后侧脑室注射5、7-双羟色胺(5、7-DHT);或者单独侧脑室注射5-HT,免疫应答都无显著变化,腹腔注射5-HT后,免疫应答减弱。给予赛庚啶阻断5-HT的受体后,免疫应答增强。本研究结果提示:5-HT对体液免疫应答具有抑制作用;此作用是通过外周途径实现的;其机制可能与免疫细胞上的5-HT受体有关。     

Abrogation of ICOS/ICOS ligand costimulation in NOD mice results in autoimmune deviation toward the neuromuscular system

NOD mice spontaneously develop insulin‐dependent diabetes around 10–40 wk of age. Numerous immune gene variants contribute to the autoimmune process. However, genes that direct the autoimmune response toward β cells remain ill defined. In this study, we provide evidence that the Icos and Icosl genes contribute to the diabetes process. Protection from diabetes in ICOS^?/? and ICOSL^?/? NOD mice was unexpectedly associated with the development of an autoimmune disorder of the neuro‐muscular system, characterized by myositis, sensory ganglionitis and, to a reduced extent, inflammatory infiltrates in the CNS. This syndrome was reproduced upon adoptive transfer of CD4⁺ and CD8⁺ T cells from diseased donors to naïve NOD.scid recipients. Our data further show that protection from diabetes results from defective activation of autoimmune diabetogenic effector T cells in ICOS^?/? NOD mice, whereas acceleration of diabetes in BDC2.5 ICOS^?/? NOD mice is induced by a dominant defect in Treg. Taken together, our findings indicate that costimulation signals play a key role in regulating immune tolerance in peripheral tissues and that the ICOS/ICOSL costimulatory pathway influences the balance between Treg and diabetogenic effector T cells.     

滤泡辅助性T细胞(T_(fh))的研究进展

T细胞辅助B细胞抗体的生成是体液免疫应答的中心环节.但直到最近,科学家们才对T细胞辅助B细胞的细胞及分子机制有了更清楚的认识.滤泡辅助性T细胞(T follicular helper cells,Tfh)是最近明确的一种新的CD4+T细胞亚群,其主要功能是辅助B细胞参与体液免疫.Tfh的表型和功能与其他CD4+T细胞亚群有所不同,包括趋化因子受体的表达(如CXCR5)、定位和迁移(Tfh存在于B细胞滤泡)及其辅助B细胞的功能.Tfh产生的细胞因子IL-21在Tfh功能中处于核心地位,通过与其受体IL-21R结合,可有效地刺激B细胞分化成抗体形成细胞.因此Tfh细胞相关分子(如ICOS或IL-21)的高表达或低表达,很可能与某些自身免疫性疾病或免疫缺陷疾病的发病有关.     

体内电转染增强基因免疫诱导的HBV特异性体液免疫应答

为观察体内电转染对HBV基因免疫诱导的特异性体液免疫应答的调节作用,将HBV-preS2/S编码基因插入pVAON33载体构建重组质粒pVAON33-preS2/S,运用肌肉注射法对BALB/c小鼠进行基因免疫(100ug质粒DNA.100ul.只)。以pVAON33-preS2/S、pVAON33-preS2/S(体内电转染)为实验组,并以pVAON33空质粒为对照。按期采集免疫小鼠血清。采用ELISA法检测免疫小鼠血清特异性抗HBs-IgG抗体。结果显示,pVAON33-preS2/S免疫小鼠后可诱导产生特异性抗HBs-IgG抗体,到第7周时其OD值为0.73±0.18(P/N为2.13),而pVAON33-preS2/S(体内电转染)组诱导了更高水平的特异性抗HBs-IgG抗体,第7周时OD值为1.30±0.45(P/N为3.79),两组比较有显著性差异(P<0.05)。本研究表明体内电转染可明显增强HBV基因免疫诱导的体液免疫应答。     

狂犬疫苗接种诱生细胞免疫的研究

狂犬疫苗对免疫接种志愿者和免疫实验小鼠能诱导产生显著的细胞介导免疫应答。免疫接种者的外周血淋巴细胞在体外经刀豆球蛋白Ａ刺激呈很强的增殖反应，增殖指数（ＳＩ）达８．５％－１５．４％；在ＨｐＢＬ的ＣｏｎＡ培养上清中可测及白细胞介素２（ＩＬ－２）活性明显升高。在接种者的血清中还可测及高水平干扰素。免疫试验小鼠其脾淋巴细胞在体外用不同狂犬病毒株抗原进行刺激亦呈显著的特异性增殖反应，ＳＩ达７．４％－１８．３     

Bronchial Reactivity in Relation to Immune Responses in Rats after Subcutaneous Sensitization without Adjuvant

Rats of BN×Wi/Fu strain were immunized by daily subcutaneous (S.C.) injections of antigen without the use of adjuvant for two 2-week periods with a 4-week interval. The bronchial responses to airway and intravenous (i.v.) antigen challenge were measured during and after the immunization period. These responses were compared with both the humoral and the cell-mediated immune response of the animals. Immunization induced bronchial reactivity of the animals to antigen after airway and i.v. challenge. This reactivity persisted for 7 weeks following the second immunization period. Specific IgE antibodies were detected in serum, bronchial fluid and in supernatants from cultured peripheral lymph node cells. The immunization also resulted in an IgG antibody response. Neither the amount of IgE. IgG2a, nor of any other isotype, correlated with the bronchial reactivity in the animals. Antigen simulation of lymph node cells mixed with syngeneic spleen cells induced proliferation. This procedure also resulted in a maturation of mast cells in 3-week cultures. The immunization also resulted in some increase in the number of mast cells around vessels in the lung. There was no correlation between these parameters of cell-mediated immunity and either antibody responses or bronchial reactivity.     

The Lymph Node Revisited: Development,Morphology, Functioning,and Role in Triggering Primary Immune Responses

Scenarios have been proposed to explain how lymphoid components of a lymph node favor the encounter of a drained antigen with a circulating competent naïve lymphocyte to trigger a primary immune response. However, these scenarios rest on incorrect concepts about the organ. This situation resulted from a loss of interest for studies on in vivo lymphoid organs due to a widespread switch, decades ago, to work on suspended lymphoid cells. However, an in vivo holistic study of the organ continued in our laboratory. The present review synthesizes resulting knowledge on lymph node morphology and global functioning. We show that the opening of an afferent lymphatic vessel into the subcapsular sinus is the focal point from which the related portion of a lymph node—a node compartment—is developed. As to the formation of a compartment's lymphoid components, it is neonatally orchestrated by the dichotomic nature and distribution of antigens in this subcapsular sinus, which determines a dichotomic recruitment of circulating cells and the compartment's architectural complexity. The transport process of an antigen from a given tissue territory into restricted sites of the draining compartment further defines its local morphological features and activities, while providing the possibility to reduce the wandering of a short‐lived naïve cell through innumerable target‐devoid sites. We also explain that the nodal lymphoid components are not implicated in the triggering of primary responses, but are rather products of such responses. Scenarios for the triggering of primary responses, consistent with real node morphology and functioning, are proposed. Anat Rec, 293:320–337, 2010. © 2010 Wiley‐Liss, Inc.     

Graves病患者外周血T细胞亚群和共刺激分子的表达及其意义

为研究Graves病患者外周血T细胞亚群及共刺激分子的表达 ,并探讨其在Graves免疫病理机制中的作用 ,本文采用免疫荧光标记和流式细胞仪术检测了 19例Graves病患者和 11例正常人外周血T细胞亚群及共刺激分子 (CD2 8、B7、CD40、CD40L、 4 1BB、OX40 )的表达。结果表明 ,19例初诊Graves病患者外周血T细胞亚群呈现异常改变 ,表现为CD3+ 和CD4+T细胞显著下降 (P <0 0 5 ,P <0 0 1) ,CD4+ /CD8+ T细胞比值倒置 (P <0 0 1) ,共刺激分子CD2 8在T细胞中的表达水平明显下降 (P <0 0 1) ,T细胞亚群CD4+ CD2 8+ 、CD8+ CD2 8+ 细胞数量均减少 (P <0 0 5 ,P <0 0 1) ,而 4 1BB分子表达显著地升高 (P <0 0 5 )。随防 10例治疗后缓解患者 ,T细胞亚群失衡明显改善 ,共刺激分子CD2 8的表达水平上调 (P <0 0 1) ,而4 1BB分子的表达明显下降 (P <0 0 1) ,T细胞亚群CD4+ CD2 8+ 、CD8+ CD2 8+ 细胞数量均增加 (P <0 0 1) ,甲状腺自身抗体甲状腺球蛋白抗体 (TGAb )和甲状腺微粒体抗体 (TMAb )的表达水平均下降 (P <0 0 1,P <0 0 1)。从而表明 ,T细胞亚群的异常及共刺激分子CD2 8、 4 1BB的表达改变与Graves病的免疫病理机制相关。