Studies on the analysis of antigen recognition mechanisms of Lyt- <1^+> <2^-> T cells mediating in vivo cell-mediated immunity and the regulation of induction of these cells.

本研究旨在(1)建立能够评估体内各种免疫反应的Lyt- <1^+> <2^-> T细胞活性的各种检测系统；(2)分析这些T细胞识别抗原的机制；(3)通过调节Lyt- <1^+> <2^-> T细胞的诱导来研究体内免疫现象的操纵，如肿瘤或异体移植排斥和自身免疫性疾病评估各种Lyt- <1^+> <2^-> T细胞活性。这些包括辅助T细胞活性，协助CTL或对细胞结合抗原（细胞表面抗原）的抗体反应，以及延迟型超敏反应；(2) lyt- <1^+> <2^-> T细胞可以识别细胞表面抗原，当这些抗原从细胞表面脱落，经过抗原呈递细胞（APC）处理，并由APC与APC上的II类MHC抗原联合呈递；(3)门静脉给药异体细胞导致对延迟型超敏反应的异体抗原特异性耐受，这种方法适用于移植免疫的调节，特别是当与合适的药物如环磷酰胺联合使用时。

This purpose aimed to (1) establish various assay systems capable assessing activities of Lyt- <1^+> <2^-> T cells responsible for various immune responses in vivo and (2) to analyze the mechanisms by which these T cells recognize antigens and (3) to investigate the manipulation of in vivo immune phenomena such as tumor or allograft rejections and autoimmune disease by regulating the induction of the Lyt- <1^+> <2^-> T cellsThe results demonstrated that (1) assay systems were established for assessing various Lyt- <1^+> <2^-> T cell activities. These included helper T cell activities assisting CTL or antibody responses to cell-bound antigens (cell surface antigens), and delayed-type hypersensitivity responses; (2) lyt- <1^+> <2^-> T cells can recognize cell surface antigens when these antigens are shed off from cell surfaces, processed by antigen-presenting cells (APC) and presented by APC in association with class II MHC antigens on APC; and (3) portal venous administration of allogeneic cells results in alloantigen-specific tolerance of delayed-type hypersensitivity responses and this approach is applicable to the regulation of transplantation immunity particularly when combined with an appropriate drug such as cyclophos-phamide.