Mechanisms of the initiation and regulation of immune responses by accessory cells

T细胞反应的启动依赖于非TIa细胞的空气，通常被称为“辅助细胞(A细胞)”。到目前为止，我们已经阐明，静止的T细胞只能在树突状细胞(DC)的帮助下被激活，但一旦被激活，T胚样细胞就会对Ia^+巨噬细胞(M&lt；Phi&gt；)和B细胞产生反应。在这两年中，我们对A细胞启动和调节T细胞反应的机制进行了研究，取得了以下结果。幼年动物M&lt；Phi&Gt；的IA表达被其自身分泌的干扰素β所抑制。不同品系小鼠树突状细胞的功能衰退随年龄增长而不同。M&lt；Phi&Gt；对免疫T细胞的混合白细胞反应、一抗反应和二次增殖反应的增强作用是由M&lt；Phi&Gt；自身产生的IL-1和GM-CSF介导的。这些因素的花环是DC，而不是T细胞。神经氨酸酶处理的M&lt；Phi&Gt；在IL-2存在的情况下从CD4^-8^+细胞诱导细胞毒性T淋巴细胞，而不是在CD4^+8^-T细胞的帮助下。Ia^+A细胞的存在不是必需的。

Initiation of T cell responses depends on the air of non-T Ia-bearing cells generally called "accessory cells (A-cells)". We have so far elucidated that the resting T cells are activated only by the aid of dendritic cells (DC), but once activated T blastoid cells become responsive to Ia^+ macrophages (M<phi>) and also to B cells. In these two years, we have investigated mechanisms of the initiation and regulation of T cell responses by A-cells, and obtained the results below.1. Ia expression on M<phi> of infant animals is suppressed fby their autocrine of interferonbeta.2. Functonal decline of dendritic cells with ageing is different among mouse strains.3. The enhancing effect of M<phi> on mixed leukocyte reaction, primary antibody respones, and secondary proliferative response of immune T cells is mediated by IL-1 and GM-CSF which are produced by M<phi> themselves. The garget of these factors is DC but not T cells.4. Neuraminidase-treated M<phi> induce cytotoxic T lymphocytes from CD4^-8^+ cells in the presence of IL-2 without the help of CD4^+8^- T cells. The presence of Ia^+ A-cells is not required.