HIV感染后CD4~+ T细胞表面NK相关受体表达的变化

目的研究人类免疫缺陷病毒(human immunodeficiency virus,HIV)感染后CD4+T细胞表面NK相关受体表达的变化。方法选取25例未经高效抗逆转录病毒治疗的HIV感染者、11例AIDS患者、15例进行高效抗逆转录病毒治疗(highly activeantiretroviral therapy,HAART)者和13例HIV抗体阴性健康对照,用流式细胞仪检测研究对象外周血CD4+T细胞表面NKG2D、NKG2A和KIR3DL1的表达。结果 AIDS患者CD4+T细胞表面NKG2D表达的百分比显著高于其他各组,且NKG2D表达的百分比与CD4+T细胞的绝对数量呈负相关(R=-0.352,P<0.05),与HIV病毒载量呈正相关(R=0.426,P<0.05)。AIDS患者CD4+T表面NKG2A表达的百分比显著高于其他各组,NKG2A+NKG2D-表达的百分比显著高于其他各组,且NKG2A表达的百分比与CD4+T细胞的绝对数量呈负相关(R=-0.432,P<0.01)。结论 HIV感染机体后,CD4+T细胞NK相关受体表达变化与疾病进展相关。     

HIV原发感染者自然杀伤样T细胞NKG2A/NKG2D变化的研究

目的深入了解人类免疫缺陷病毒(human immunodeficiency virus,HIV)原发感染者(primary HIV infection,PHI)NKT样细胞表面NKG2A/NKG2D受体表达的变化。方法选取25例未经高效抗逆转录病毒治疗的HIV原发感染者和27例HIV抗体阴性健康对照,用流式细胞仪检测研究对象外周血NKT样细胞表面NKG2D和NKG2A的表达。结果 HIV原发感染者NKT样细胞绝对数和百分率显著低于健康对照(P<0.01)。HIV原发感染者NKT样细胞表面NKG2A、NKG2D受体表达与健康对照并无显著差异。HIV原发感染者病毒调定点低组NKG2A+NKT样细胞、NKG2A+NKG2D-NKT样细胞以及NKG2A+NKG2D+NKT样细胞百分率均显著低于病毒调定点高组(P<0.05);NKT细胞绝对数和百分率、NKG2D+NKT样细胞、NKG2D+NKG2A-NKT样细胞百分率在两组间相似,没有显著性差异。NKG2A+NKT细胞的百分比与病毒载量正相关(R=0.430,P=0.032)。结论 NKT样细胞数量以及其表面NKG2A受体的表达可作为HIV疾病进程的预测指标之一。     

HIV感染者T细胞NKG2C/NKG2A表达及与疾病进展关系研究

目的：研究HIV慢性感染者和HARRT治疗者T细胞NKG2C/NKG2A受体的表达变化,探讨其与疾病进展的关系。方法：选取HIV慢性感染者、接受HAART治疗的HIV感染者以及健康人的外周血细胞,通过荧光抗体染色,利用流式细胞仪检测T细胞上表达的NKG2C/NKG2A受体。结果：HIV慢性感染者NKG2C⁺ T细胞,NKG2A⁺ T细胞和NKG2C+NKG2A- T细胞百分比明显高于健康对照组 (P=0.025、P=0.032、P=0.029),HARRT治疗组则明显低于HIV慢性感染者(P=0.033、P=0.037、P=0.018),恢复到正常水平,与健康对照组相比无统计学差异。HIV慢性感染者外周血CD4⁺ T淋巴细胞绝对数和表达NKG2A、NKG2C⁺NKG2A⁺和NKG2C-NKG2A⁺ 的T细胞呈负相关(r=-0.697,P<0.000 1;r=-0.463,P=0.015;r=-0.693,P<0.000 1),HIV慢性感染者外周血T细胞上表达的NKG2C与NKG2A的比值与CD4⁺ T淋巴细胞绝对数呈正相关(r=0.476,P=0.012)。结论：HIV感染者T细胞表面NKG2C和NKG2A的表达研究具有重要意义,为HIV感染的临床预后评估提供科学依据。     

NKG2D与NKG2DL在肺癌免疫调节中的作用及临床意义

NKG2D与NKG2DL是目前研究的热点,NKG2D可表达于几乎所有的NK细胞、CD8+αβT细胞、γδ T细胞及少量CD4+αβT细胞的细胞膜表面,与其配体NKG2DL结合后,可激活NK细胞及T细胞,诱导机体的抗肿瘤免疫应答,杀伤表达NKG2DL的肿瘤细胞,因此,NKG2D及其配体NKG2DL在肿瘤的免疫调节过程中起着极其重要的作用.目前肺癌的预后仍不容乐观,迫切需要发展一种新型的治疗方法来达到特异杀灭肿瘤细胞而不损伤或仅轻微损伤正常细胞的目的,这使得免疫疗法成为一种极具吸引力及应用前景的治疗肺癌的方法.     

传染性单核细胞增多症患儿NKG2D表达变化初探

目的 观察传染性单核细胞增多症(infectious mononucleosis,IM)患儿自然杀伤(NK)细胞和CD8+T细胞NKG2D表达,探讨导致Epstein-Barr病毒(EBV)感染免疫功能紊乱的可能机制.方法 传染性单核细胞增多症患儿29例,同龄健康对照组25例.流式细胞术检测外周血NK细胞、CD8+T细胞表面激活性受体NKG2D及抑制性受体NKG2A表达,CD14+单核细胞(MC)表面NKG2D配体MHC Ⅰ相关分子A(MICA)与人巨细胞病毒蛋白UL16的结合蛋白1(ULBP-1)表达;酶联免疫吸附试验(EHSA)检测血浆游离MICA (sMICA)、IL-7、IL-12、IL-15、IFN-γ及TGF-β等细胞因子浓度.结果 (1)IM组患儿NK细胞及CD8+T细胞表面NKG2D表达明显低于对照组(P＜0.05),其中3例拟诊EBV-相关噬血细胞综合征(EBV-HLH)患儿表达下调最为显著;(2)IM组患儿CD14+ MC MICA与ULBP-1表达与对照组相比差异无统计学意义(P＞0.05);(3)IM患儿细胞因子IL-15与TGF-β较对照组降低,IL-7、IL-12、IFN-γ及sMICA较对照组升高;(4)IM患儿NK细胞NKG2A表达明显高于对照组(P＜0.05),CD8+T细胞NKG2A表达与对照组相比无明显差异(P＞0.05).结论 EBV感染患儿NK细胞、CD8+T细胞NKG2D表达过度下调可能是导致免疫功能紊乱的原因之一,IL-15及IL-12等细胞因子调控失衡,sMICA血浓度增高等多种因素可能与其NKG2D表达下调有关.     

中国HIV/AIDS患者NK细胞及NKT细胞变化的检测

目的　探讨HIV感染后机体NK(naturalkillercells)及NKT细胞的变化情况。方法　取外周血细胞 ,用标记荧光的抗体进行染色 ,流式细胞仪分析HIV AIDS患者NK和NKT细胞的变化。结果　HIV AIDS患者NK、NKT细胞和CD4 + T细胞显著低于正常对照 ;CD8+ T细胞显著高于正常对照。HIV AIDS患者NK百分数显著低于正常对照 ,与CD4 + T细胞数量成正比 ,r=0 .2 89,P <0 .0 1 ;NKT细胞数量与CD4 + T细胞数量成正比 ,r =0 .378,P <0 .0 1 ;与CD8+ T细胞数量成正比 ,r =0 .340 ,P <0 .0 1 ;长期不进展组NKT、NK细胞数量与正常对照组差异无显著性。结论　HIV感染可明显降低HIV AIDS患者NK和NKT细胞数量 ,NK和NKT细胞变化与疾病进展密切相关。     

人外周血NK细胞及NKT细胞受体及亚群的差异表达与类风湿关节炎的关系

目的:探讨初诊类风湿关节炎(RA)患者的外周血NK和NKT细胞的活化性、抑制性受体及亚群表达水平的变化,揭示其在RA发病中的可能机制。方法:检测32例初诊RA患者和15例健康人的外周血NK和NKT细胞及其活化性受体和抑制性受体,对自发和刺激后的NK、NKT细胞分泌的IFN-γ、NKT细胞和CD107a+NK细胞进行检测,分析各细胞亚群与临床指标之间的潜在关系。结果:与健康对照组相比,初诊RA患者的NK细胞的比例显著降低(P=0.026);RA患者NK细胞活化性受体NKG2D+,NKP46+和NKT细胞活化性受体NKG2C+,NKG2D+,NKP46+的比例显著增高(P=0.011,P=0.010,P<0.001,P=0.032,P=0.001);NK细胞抑制性受体KIR2DL3+、KIR3DL1+和NKG2A+和NKT细胞抑制性受体KIR2DL3+,NKG2A+的比例显著降低(P=0.002,P=0.002,P=0.014,P=0.027,P=0.002);刺激后的IFN-γ+NK和IFN-γ+NKT细胞的比例,自发和刺激后的CD107a+NK细胞的比例在RA患者中要显著高于对照组(P=0.037,P=0.004,P=0.001,P=0.001)。此外,NK细胞、抑制性NK细胞受体NKG2A+和KIR2DL3+的比例和初诊RA患者的DAS28值显著相关(r=0.357,P=0.045;r=0.399,P=0.024;r=0.468,P=0.021)。结论:人外周血NK细胞及NKT细胞受体及亚群的差异表达、细胞功能的变化可能诱发RA的自身免疫反应。     

活化性受体NKG2D及其配体的研究进展

NK细胞是肌体免疫系统至关重要的组成部分，其表达多种活化性和抑制性细胞表面受体。NKG2D是较为独特的活化性受体，属C型凝集素家族跨膜蛋白，分布较广，NK细胞、T细胞和其他免疫细胞都可以产生，其配体具有多样性，MHCⅠ类相关分子（MIC）是人类NKG2D识别的配体之一，应激性表达在一些肿瘤细胞或病原体感染细胞的表面。NKG2D既能直接活化NK细胞，又能以协同刺激的方式促进CD8^＋αβT细胞的活化，在抗肿瘤免疫和病毒感染等方面发挥重要作用。     

HIV/AIDS患者CD28在外周血CD4+、CD8+ T细胞上的表达变化

目的　研究国内HIV AIDS患者CD2 8在外周血CD4 + 、CD8+ T淋巴细胞上表达的变化 ,并探讨这些变化的临床意义。方法　用流式细胞仪检测 5 1例正常对照、14例HIV感染者和 36例AIDS患者的外周血CD4 + 、CD8+ T淋巴细胞表面的CD2 8分子的表达 ,用bDNA法检测 11例HIV感染者和 18例AIDS患者的血浆病毒载量。结果　CD4 + CD2 8+ T细胞的绝对计数与百分比、CD8+ CD2 8+T细胞的百分比均显示为正常对照组 >HIV感染组 >AIDS组 ;而CD8+ CD2 8+ T细胞的绝对计数显示HIV感染组和对照组显著大于AIDS组 ,HIV感染组与对照组间差异无显著性。CD4 + 、CD2 8+ CD4 + T淋巴细胞计数与血浆病毒载量显著负相关。结论　HIV AIDS患者外周血CD2 8在CD4 + 、CD8+ T淋巴细胞上表达随着病情进展而降低 ,反映了细胞免疫功能随着疾病进展损害逐渐加重 ,是判断病情进展的指标。     

外周血纯真、记忆性CD8~+T细胞数量与中国HIV/AIDS患者疾病进程的相关性研究

目的:研究不同疾病进展阶段的中国HIV/AIDS患者外周血CD8+T细胞亚群的数量变化,以探讨各亚群与HIV感染疾病进展的相关性。方法:首先应用多参数(CD45RA、CCR7、CD28)流式细胞术圈定幼稚(nave)CD8+T细胞和记忆性(memory)CD8+T细胞(包括TCM、TEM-1及TEM-2),随后测定58例不同疾病进展阶段HIV/AIDS患者和20例健康对照者外周血各CD8+T细胞亚群的绝对数量和占CD8+T细胞的百分比,分析其与病毒载量、CD4+T细胞数量的相关性。结果:HIV/AIDS患者与健康对照相比,nave CD8+T细胞百分比和绝对值均显著减少,memory CD8+T细胞百分比和绝对值均显著升高(P0.05)。在memoryCD8+T细胞各亚群中,效应型(effector memory T cells,TEM)-1百分比显著升高(P0.05)。HIV感染缓慢进展(slow progressor,SP)组、HIV组及AIDS组中,nave CD8+T细胞百分比和绝对值均依次下降,AIDS组、HIV组显著低于SP组(P0.05),memory CD8+T细胞绝对值依次下降,各组间的下降均有显著性差异(P0.05)。在memory CD8+T细胞各亚群中,TEM-1百分比依次升高,AIDS组显著高于SP组(P0.05);TEM-2百分比及绝对值依次下降,AIDS组显著低于SP组(P0.05)。相关性分析发现,nave CD8+T细胞与CD4+T细胞显著正相关(P0.01),与HIV病毒载量显著负相关(P0.01);中央型(central memory T cells,TCM)和TEM-2型memory CD8+T细胞与CD4+T细胞显著正相关(P0.01)。结论:Nave、memory CD8+T细胞数量与HIV疾病进展显著相关。     

HIV感染后胃黏膜CD4+、CD8+T细胞数量分布及CD38表达的改变

目的 研究不同感染阶段HIV感染者胃黏膜中CD4+和CD8+T细胞数量和分布情况,及免疫细胞激活状态的改变.方法 有胃黏膜组织活检标本的HIV感染者42例,其中有明确临床分期诊断的36例,另选非HIV感染者胃黏膜组织活检标本10例为对照,利用免疫组织化学方法检测研究对象胃黏膜活检组织中CD4、CD8及CD38的表达,以图像分析系统分析其差异.结果 (1)AIDS患者胃黏膜中CD4+T细胞与对照组和无症状者相比,均显著减少(P(0.01),无症状者多数淋巴滤泡中仍有一定量CD4+T细胞,间质中多呈不均匀聚集分布,统计学与正常对照组差异无统计学意义(P>0.05);(2)HIV感染者胃黏膜内CD8+T细胞普遍噬腺体和黏膜上皮,部分病例胃黏膜内CD8+T细胞局部过度增生,与对照组相比,CD8+T细胞在感染者胃黏膜中显著增多(P<0.01),无症状者与AIDS患者CD8+T细胞差异无统计学意义(P>0.05);(3)在HIV感染者胃黏膜内,CD38阳性细胞主要分布于黏膜表层至浅1/3～2/3层,与对照组相比,HIV感染者胃黏膜中CD38表达增强(P<0.01),无症状者与MDS患者CD38表达差异无统计学意义(P>0.05).结论 HIV感染者胃黏膜中CD4+T细胞的数量和分布与疾病进展有密切联系,HIV对CD4+T细胞的感染和破坏导致黏膜免疫系统功能异常,可能是胃黏膜内CD8+T细胞数量增加,CD38表达增强的重要原因之一.     

Expression of killer inhibitory receptors on cytotoxic cells from HIV-1-infected individuals

Dysfunction of cytotoxic activity of T and natural killer (NK) lymphocytes is a main immunological feature in patients with AIDS, but its basis are not well understood. It has been recently described that T and NK cell-mediated cytotoxicity can be regulated by HLA killer inhibitory receptors (KIR). In this work, we have determined on cytotoxic T cells and NK cells from HIV-1-infected individuals the expression of the following KIR molecules: p58, p70, and ILT2 (immunoglobulin-like family KIR) as well as CD94 and NKG2A (C-lectin-type family KIR). With some exceptions, no significant changes were found on the expression of immunoglobulin-like KIR in either CD8+ or CD56+ cells. Interestingly, the percentages of CD8+ and CD56+ cells expressing CD94 were significantly increased in these individuals. We also show that, in vitro, IL-10 up-regulates CD94 expression on CD8+ and CD56+ cells obtained from normal individuals, suggesting that the augmented expression observed in HIV-infected individuals could be related to the high levels of IL-10 previously described in HIV-1-infected individuals.     

UL16 binding proteins

According to present concepts, innate immunity plays an important role in tumor surveillance and immune modulation. The state of NK cells depends on the balance between inhibitory and activating signals from corresponding receptors. As one of the activating receptors, NKG2D recognises some self ligands such as MICA/B in human and Rae1 in mice, which is dissimilar to those toll-like receptors that recognise some pathogen-derived ligands. NKG2D is expressed not only on NK cells, but on gammadelta T cells, CD8+ alphabeta T cells in normal individuals and CD4+ alphabeta T cells in rheumatoid arthritis patients and plays a different role on respective cells. Whereas NKG2D can only function as a costimulatory receptor on CD8+ alphabeta T cells under the domination of alphabeta TCR in spite of a deficiency of costimulatory molecule CD28, NKG2D can directly activate NK cells even in the presence of inhibitory signals from MHC-I and corresponding receptor complexes. Experiments in mice have identified that alternative splicing produces two distinct NKG2D polypeptides that associate differentially with the DAP10 and DAP12 signaling subunits and that differential expression of these isoforms and of signaling proteins determines whether NKG2D only functions as a costimulatory receptor in the adaptive immune system (CD8+ T cells) or as both a primary recognition unit and a costimulatory receptor in the innate immune system (natural killer cells and macrophages). This review summarizes the research achievements in a new ligand family (UL16 binding proteins) of NKG2D in human and shows the possible prospects of ULBP function and application.     

Expression and function of NKG2D in CD4+ T cells specific for human cytomegalovirus

The human NKG2D killer lectin-like receptor (KLR) is coupled by the DAP10 adapter to phosphoinositide 3-kinase (PI3 K) and specifically interacts with different stress-inducible molecules (i.e. MICA, MICB, ULBP) displayed by some tumour and virus-infected cells. This KLR is commonly expressed by human NK cells as well as TCRgammadelta(+) and TCRalphabeta(+)CD8(+) T lymphocytes, but it has been also detected in CD4(+) T cells from rheumatoid arthritis and cancer patients. In the present study, we analysed NKG2D expression in human cytomegalovirus (HCMV)-specific CD4(+) T lymphocytes. In vitro stimulation of peripheral blood mononuclear cells (PBMC) from healthy seropositive individuals with HCMV promoted variable expansion of CD4(+)NKG2D(+) T lymphocytes that coexpressed perforin. NKG2D was detected in CD28(-) and CD28(dull )subsets and was not systematically associated with the expression of other NK cell receptors (i.e. KIR, CD94/NKG2 and ILT2). Engagement of NKG2D with specific mAb synergized with TCR-dependent activation of CD4(+) T cells, triggering proliferation and cytokine production (i.e. IFN-gamma and TNF-alpha). Altogether, the data support the notion that NKG2D functions as a prototypic costimulatory receptor in a subset of HCMV-specific CD4(+) T lymphocytes and thus may have a role in the response against infected HLA class II(+) cells displaying NKG2D ligands.     

中国HIV/AIDS患者T细胞及调节性T细胞CTLA-4表达与疾病进展关系研究

目的 对中国HIV感染者T细胞及凋节性T细胞CTLA-4表达与HIV疾病进展的相关性进行研究,探讨CTLA-4在HIV感染中的作用.方法 选取58名HIV/AIDS患者(长期不进展组、无症状HIV组、AIDS组),应用流式细胞仪胞内染色技术检测T细胞及CD4+CD25+Foxp3+调节性T细胞内CTLA-4表达水平,分析其与CD4+T细胞、病毒载量、淋巴细胞活化凋亡水平的相关性.结果 长期不进展组、无症状HIV组、AIDS组CD4+T细胞内CTLA-4表达水平依次增岛(P<0.05);与CD+T细胞显著负相关(P<0.01),与CD8+T细胞活化(CD38表达)、凋亡水平(CD95表达)及CD4+T细胞凋亡水平显著相关(P<0.05),与病毒载量无显著相关性.长期不进展组、无症状HIV组、AIDS组CD8+T细胞内CTLA-4表达水平差异无统计学意义;与CD4+T细胞、病毒载量、CD4,'+>、CD8+T细胞活化及凋亡水平均无显著相关性.CD4+CD25+Foxp3+T细胞内CTLA-4表达水平长期不进展组明显低于无症状HIV组及AIDS纽(P<0.05);与CD4+T细胞显著负相关(P<0.05);与CD4+、CD8+T淋巴细胞活化(HLA-DR表达)显著相关(P<0.01).结论 中国HIV感染者CD4+T细胞及CD4+CD25+Foxp3+调节性T细胞内CTLA-4表达水平与疾病进展及免疫活化状态显著相关,参与HIV感染免疫平衡的调节.     

The CD94/NKG2C killer lectin-like receptor constitutes an alternative activation pathway for a subset of CD8+ T cells

The CD94/NKG2C killer lectin-like receptor (KLR) specific for HLA-E is coupled to the KARAP/DAP12 adapter in a subset of NK cells, triggering their effector functions. We have studied the distribution and function of this KLR in T lymphocytes. Like other NK cell receptors (NKR), CD94/NKG2C was predominantly expressed by a CD8(+) T cell subset, though TCRgammadelta(+) NKG2C(+) and rare CD4(+) NKG2C(+) cells were also detected in some individuals. Coculture with the 721.221 HLA class I-deficient lymphoma cell line transfected with HLA-E (.221-AEH) induced IL-2Ralpha expression in CD94/NKG2C+ NK cells and a minor subset of CD94/NKG2C(+) T cells, promoting their proliferation; moreover, a similar response was triggered upon selective engagement of CD94/NKG2C with a specific mAb. CD8(+) TCRalphabeta CD94/NKG2C(+) T cell clones, that displayed different combinations of KIR and CD85j receptors, expressed KARAP/DAP12 which was co-precipitated by an anti-CD94 mAb. Specific engagement of the KLR triggered cytotoxicity and cytokine production in CD94/NKG2C(+) T cell clones, inducing as well IL-2Ralpha expression and a proliferative response. Altogether these results support that CD94/NKG2C may constitute an alternative T cell activation pathway capable of driving the expansion and triggering the effector functions of a CTL subset.     

中国HIV感染长期不进展者CD4+CD25+Foxp3+调节性T细胞变化研究

目的 对中国HIV感染长期不进展者(LTNP)CD4+CD25+Foxp3+调节性T细胞水平及其与疾病进展相关性进行研究,探讨CD4+CD25+Foxp3+ 调节性T细胞在LTNP保护机制中发挥的作用.方法 选取74名HIV-1感染者(LTNP、典型进展HIV组、AIDS组)及16名健康对照,应用流式细胞仪胞内染色技术在单细胞水平检测CD4+CD25+Foxp3+调节性T细胞表达水平,分析其与CD4+ T细胞数量、病毒载量、淋巴细胞活化、凋亡水平的相关性.结果 中国HIV感染LTNP CD4+CD25+Foxp3+ T细胞百分率明显低于典型进展HIV、AIDS组及健康对照组(P<0.05).HIV/AIDS患者CD4+CD25+Foxp3+ T细胞百分率与CD4+ T细胞显著负相关(r=-0.509,P<0.001),与病毒载量明显正相关(r=0.414,P<0.01),与CD4、CD8+ T细胞表面CD38、CD95表达水平明显正相关(P<0.05),与CD4、CD8+ T细胞表面HLA-DR表达无显著相关性.结论 中国HIV感染LTNP CD4+CD25+Foxp3+ 调节性T细胞百分率明显低于典型进展者,提示调节性T细胞与LTNP保护机制相关.