巨噬细胞细胞毒因子性质的研究

Studies on Characteristics of Macrophage-derived Cytotoxic Factor

巨噬细胞(MΦ)经多种因素活化后能非特异但有选择地杀伤瘤细胞。这种杀伤作用是通过细胞毒介质实现的,但对其本质尚有不同的认识,一股认为是肿瘤坏死因产(TNF),中性蛋白水解酶、补体C3a和过氧化氢。本文报道钙离子载体A23187活化的MΦ经微量细菌脂多糖(LPS)刺激后产生的1种巨噬细胞细胞毒因子(MΦ-CF),根据其理化性质和生物学活性,证实其为TNF或TNF样物质。

Macrophage-derived cytotoxic factor (MΦ-CF) obtained from murine peritoneal macrophages stimulated with calcium ionophore A 23187 and lipopolysacchride was characterized. It had a relative molecular mass of 52000±3400 Daltons as determined by gel filtration on Sephadex G-100 column. It was stable in a pH range of 6～10, and at 56℃ for 1 h. It was sensitive to pronase and trypsin, but its cytotoxicity was not destroyed by pepsin or 2-mercaptoethanol. Protease inhibitors (phenylmethylsulfonyl fluoride, 8-hydroxyquinine, and soybean trypsin inhibitor) had no significant effect on its cytotoxicity. Pretreatment of target cells with 4β-phorbol 12β-myristate 13α-acetate (PMA) protected them from the cytotoxic effect of MΦ-CF. These characteristics of MΦ-CF are essentially similar to those of tumor necrosis factor (TNF).