Biochemical studies and medical application of immunoregulatory factors

1.人T细胞杂交瘤产生的淋巴因子：我们建立了一种利用代谢抑制剂(艾美汀和放线菌素D)构建人T细胞杂交瘤的新的筛选方法。从所建立的人T细胞杂交瘤克隆中克隆了人淋巴毒素基因，并成功地表达了大量的重组人淋巴毒素。重组人淋巴毒素在体内外对肿瘤细胞具有较强的细胞毒作用。在分析人淋巴毒素体内抗肿瘤活性的过程中，我们发现人淋巴毒素具有很强的巨噬细胞趋化和激活巨噬细胞的活性。从另一个人T细胞杂交瘤克隆H3-E9-6中，我们部分纯化了两个巨噬细胞激活因子。其中一种是MAF-CI，它是一种与人类干扰素不同的启动因子。另一种是MAF-CII，它是一种不同于内毒素的触发因子。这两种巨噬细胞激活因子对人单核细胞具有协同作用，可诱导人单核细胞产生较强的杀瘤活性。现在我们正在对这两个因子进行全面的提纯和结构研究。人和小鼠巨噬细胞杂交瘤产生的单因子：我们成功地建立了一批小鼠和人巨噬细胞杂交瘤，并对这些杂交瘤产生的各种单因子进行了分析。建立的人巨噬细胞杂交瘤克隆之一被发现分泌一种强大的肿瘤特异性细胞毒素，这种毒素不同于人淋巴毒素、肿瘤坏死因子和白介素1。

1. Lymphokines produced by human T cell hybridomas : We established a novel selection method for the construction of human T cell hybridomas using metabolic inhibitors (emetine and actinomycin D). From one of human T cell hybridoma clones thus established, we cloned cDNA for human lymphotoxin and succeeded to produce a large amounts of recombinant human lymphotoxin. The recombinant human lymphotoxin was found to exert potent cytotoxicity specifically against malignant cells in vitro and in vivo. On the process of the analysis of in vivo anti-tumor activity of human lymphotoxin, we found that human lymphotoxin has potent macrophage chemotactic and macrophage activating activities. From the other human T cell hybridoma clone, H3-E9-6, we partially purified two macrophage activating factors. One of them, MAF-CI, is a priming factor which is not identical with human <gamma>-interferone. The other, MAF-CII, is a triggering factor which is different from lipopolysaccharide. These two macrophage activating factors show a synergistic effect on human monocytes and induce strong tumoricidal activity of human monocytes. Now we are wroking on the complete purification and structural study of these two factors.2. Monokines produced by human and mouse macrophage hybridomas : We succeeded to establish a number of mouse and human macrophage hybridomas and analyzed various monokines produced by these macrophage hybridomas. One of the human macrophage hybridoma clones established was found to secrete a potent tumor-specific cytotoxin which was distinct from human lymphotoxin, tumor necrosis factor and interleukin-1.