《机体防御和免疫》t淋巴细胞介导适应性免疫应答.ppt

T 淋巴细胞介导的适应性免疫应答 T 淋巴细胞介导的适应性免疫应答 Granzyme Caspase10 FasL—Fas·DD FADD DD DED Caspase8 DNA内切酶 活化 核小体 断裂 细胞凋亡 Apoptosis * Fas 死亡分子 T 淋巴细胞介导的适应性免疫应答 医学免疫学 上海第二医科大学免疫教研室 T 淋巴细胞介导的适应性免疫应答 3. 细胞免疫应答的生物学意义 抗感染：细胞内寄生的病原体 抗肿瘤： CTL对肿瘤细胞的杀伤 细胞因子对肿瘤的直接作用 细胞因子激活巨噬细胞或NK细胞 免疫病理作用：迟发型超敏反应、移植排斥反应、自身免疫病 4. 活化T细胞的转归 效应T细胞的抑制或清除 记忆性T细胞的形成 T 淋巴细胞介导的适应性免疫应答 1）效应T细胞的抑制或清除 Treg的免疫抑制作用 活化诱导的细胞死亡 （activation-induced cell death, AICD） T 淋巴细胞介导的适应性免疫应答 活化诱导的细胞死亡（AICD） 活化T细胞表达Fas增加，多种细胞表达FasL与之结合，启动活化T细胞的凋亡信号，诱导细胞凋亡。 AICD是一种自发的细胞凋亡。 T 淋巴细胞介导的适应性免疫应答 2）记忆T细胞 记忆T细胞（Tm）：对特异性抗原有记忆能力的长寿T细胞。 Tm更易被激活；Tm活化对共刺激信号依赖性较低；Tm分泌更多细胞因子。 T 淋巴细胞介导的适应性免疫应答 T细胞对抗原的识别 T细胞的活化、增殖和分化 T 淋巴细胞介导的适应性免疫应答 T细胞的免疫效应和转归 Structure of the immunological synapse. The basic structure of the “organized” immunological synapse with SMACs is shown (left). In the center is the central supramolecular activation complex or cSMAC, which contains receptors like the TCR, CD28, CD4, CD8, and CD2. Newer studies suggest that the cSMAC may be divided into an outer area containing CD28 and an inner area containing the TCR (not shown). The ring that surrounds the cSMAC is called the peripheral supramolecular activation complex or pSMAC. This domain is mainly populated by the integrin molecule LFA-1. Outside of the pSMAC is another domain known as the distal supramolecular activation complex. Originally the dSMAC was thought not be important and contain all of the molecules that are not specifically recruited to the cSMAC or pSMAC but it is increasingly becoming appreciated that the dSMAC is an area of active membrane movement. This suggests that the pSMAC and dSMAC may be analogous to the actin structures known as the lamellae and lamellipodia, respectively (right). * 核转录因子 IL-2R、IL-2 IFN-? IL-4、-5、-6、10 CD40L FasL CTLA-4 分子 细胞 活化、分化 克隆扩增 效应细胞 Tm gene 活化表现 ZAP—70 Grb2 PLC-? fos IP3 DAG Ca++ PKC AP-1 NFAT NF-?B Gene 激活 转录 B7-CD28 MAP 激酶 PIP2 TCR PTK Lck Fyn CD4 CD8 — ITA