Lorgat F, Keraan M M, Lukey P T, Ress S R
Department of Medicine, Groote Schuur Hospital, Republic of South Africa.
Am Rev Respir Dis. 1992 Feb;145(2 Pt 1):418-23. doi: 10.1164/ajrccm/145.2_Pt_1.418.
Mycobacterium tuberculosis is a bacterial pathogen capable of survival and replication within human macrophages. Cytotoxic T cells are thought to be important for the eradication of infected macrophages. To test this hypothesis, pleural effusion lymphocytes from patients with tuberculous pleuritis were stimulated in vitro with PPD, and proliferation and cytotoxicity were assessed by thymidine incorporation and chromium release, respectively. The level and kinetics of generation of antigen-specific cytotoxicity were measured and compared with those in autologous peripheral blood, control peripheral blood, and nontuberculous effusions. Both proliferation and cytotoxicity in tuberculous pleural effusions were augmented and accelerated in comparison to autologous or control peripheral blood. By contrast, low levels of cytotoxicity were observed in nontuberculous effusions, without evidence of accelerated kinetics. Cell subset fractionation by panning indicated that the cytotoxicity was mediated by CD4+ cells. The accelerated kinetics of induction of PPD-specific cytotoxic T cells demonstrated here suggests reactivation of in vivo generated cytotoxic T cells. These findings provide evidence that cytotoxic T cells are induced at the site of pathology in vivo and suggest that these cells play an important role in protection in vivo against infection with tuberculosis.
结核分枝杆菌是一种能够在人类巨噬细胞内存活和复制的细菌病原体。细胞毒性T细胞被认为对于清除被感染的巨噬细胞很重要。为了验证这一假设，用结核菌素纯蛋白衍生物（PPD）体外刺激结核性胸膜炎患者的胸腔积液淋巴细胞，并分别通过胸腺嘧啶核苷掺入法和铬释放法评估其增殖和细胞毒性。测定抗原特异性细胞毒性的水平和产生动力学，并与自体外周血、对照外周血和非结核性胸腔积液中的情况进行比较。与自体或对照外周血相比，结核性胸腔积液中的增殖和细胞毒性均增强且加快。相比之下，在非结核性胸腔积液中观察到低水平的细胞毒性，且没有动力学加快的证据。通过淘选进行细胞亚群分离表明，细胞毒性是由CD4+细胞介导的。此处证明的PPD特异性细胞毒性T细胞诱导动力学加快表明体内产生的细胞毒性T细胞被重新激活。这些发现提供了证据，证明细胞毒性T细胞在体内病理部位被诱导产生，并表明这些细胞在体内抵御结核感染的保护中发挥重要作用。
