人免疫缺陷病毒(human immunodeficiency virus, HIV)能够通过体液、血液、母婴等途径传播，引起获得性免疫缺陷综合症(acquired immunodeficiency syndrome, AIDS)，即艾滋病。艾滋病是一种严重的传染病，尚无有效治疗及预防的方法。近年该病感染疫情日益严重，成为影响全球人类健康的严重问题。人体内CD4+T淋巴细胞是HIV的主要受体，在HIV直接和间接作用下，细胞大量被破坏和功能受损，导致细胞免疫缺陷。同时其他免疫细胞均不同程度受损，促进并发各种严重的机会性感染和肿瘤发生，导致死亡。HIV感染可能通过多种直接和间接的病理机制破坏CD4+T细胞及其他免疫细胞，如HIV的溶解细胞、感染的与未感染的CD4+T细胞的融合、病毒及病毒蛋白的毒性、超抗原、自身免疫反应以及细胞凋亡等。活化诱导的细胞死亡(activation-induced cell death, AICD)在HIV感染中的作用尤其引人注目。
AICD，是指由Fas启动的效应细胞的凋亡，又称活化诱导的细胞凋亡(activation-induced apoptosis)或抗原诱导的细胞凋亡(antigen-induced apoptosis)，也可包括其它免疫细胞的凋亡，如树突状细胞及NK细胞等。很早人们就发现，HIV感染后引起的细胞凋亡可能是CD4+T细胞进行性减少的一个重要原因。[ ]而大量无HIV感染的T淋巴细胞凋亡—即所谓“旁观者效应(Bystander effect)”—的发现更提示AICD在病毒诱发的细胞凋亡中可能起重要作用。[ ]本文就AICD在HIV感染及艾滋病中的发生机制和作用等的研究进展作一综述。
一、HIV感染中的AICD现象
CD4+T淋巴细胞是免疫系统的枢纽，在免疫系统中起着调节细胞毒CD8+T淋巴细胞(cytotoxic T-lymphocyte, CTL)、NK细胞、B细胞和抗原呈递细胞(antigen presenting cell, APC)的功能以及细胞因子的分泌等重要作用。CD4+T淋巴细胞的丢失是HIV感染的主要特征，与血浆中病毒载量水平的升高和机体免疫能力的下降有密切关系。

一、HIV感染中的AICD现象
二、HIV感染中AICD的发生机制
三、HIV感染中AICD的作用结果
四、临床应用及展望

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摘要：活化诱导的细胞死亡(AICD)是HIV感染中引起大量T细胞凋亡的重要机制之一，因而备受人们的关注。多种HIV蛋白产物都对AICD的发生有不同的作用，而机体免疫系统的激活状态等因素也直接影响AICD的发生和发展方向，最终导致患者Th/Ts比例倒置及Kaposi肉瘤发生等多种临床特征的出现。IL-16、高效抗逆转录病毒疗法(HAART)等对AICD的过程有不同的影响，从而实现抑制HIV感染和控制病程的效果。