改良型TNF-α和IFN-γ诱导小鼠腹腔巨噬细胞产生NO和细胞毒作用的影响

应用改良型ＴＮＦ α（Ｉ ＴＮＦ α）和ＩＦＮ γ刺激小鼠腹腔巨噬细胞（ＭΦ）诱生一氧化氮（ＮＯ），并观察对细胞毒作用的影响。结果：ＩＦＮ γ可激活小鼠腹腔ＭΦ产生小量ＮＯ，并伴随产生低度细胞毒活性，尤其是对经ＩＦＮ γ处理的靶细胞（γ Ｌ１２１０细胞）为显著。单用Ｉ ＴＮＦ α刺激的ＭΦ，诱生ＮＯ不显著或微量，对靶细胞也无明显细胞毒作用。但Ｉ ＴＮＦ α（１００ｎｇ／ｍｌ）和ＩＦＮ γ（５０Ｕ／ｍｌ）共同刺激ＭΦ，可产生有意义量的ＮＯ（Ｐ＜００５），对γ Ｌ１２１０细胞有显著细胞作用（Ｐ＜００１），而对未经ＩＦＮ γ处理的靶细胞（Ｌ１２１０ｃｅｌｓ）无明显细胞毒作用。这可能是ＩＦＮ γ促进ＭΦ诱生ＮＯ和靶细胞表面粘附分子的表达，加强效靶识别和结合，提高了对靶细胞的杀伤力。

Effects of Improved Type of TNF and IFN on the Induction of Nitric Oxide in Murine Macrophages and MacrophageMediated Cytotoxicity

Effects of improved type of TNF(ITNF) and IFN on the induction of nitric oxide in murine macrophages and macrophagemediated cytotoxicity were investigatedThe ITNF was constructed by gene engineering techniques with deleting 38 Nterminal amino acid residues(SerSerSerArgThrPro) and replacing with 2 residues(LysArg)The results showed that murine macrophages incubated with IFN alone or with ITNF produced little of detectable NO,but they produced significant amounts of NO when cultured with a combination of IFN and ITNF(P<005)As to the macrophage mediated cytotoxicity,if macrophages were cultured with ITNF in combination with IFN,it was significantlyaurgmented in L1210 cells pretreated with IFN(P<001)Pretreatment of L1210 cells with IFN significantly increased their susceptibility to macrophage mediatedcytotoxicity owing to the increased NO production and the expression of cell adhesion molecules