H_(22)肿瘤细胞核糖核酸对正常小鼠脾淋巴细胞的细胞毒功能影响

本文报道应用细胞介导的~(51)Cr 释放细胞毒试验观察 H_(22)TuRNA 体外对正常小鼠脾淋巴细胞细胞毒功能的影响。结果表明,当以≥250μg H_(22)TuRNA/1×10~7淋巴细胞的比例将两者在37℃共育≥60分钟,H_(22)TuRNA 可显著抑制淋巴细胞的细胞毒功能,效应具有明显的剂量依赖性。牛胰核糖核酸酶处理并不能消除 H_(22)TuRNA 的抑制效应,酶处理后样品的电泳图谱表明,具有抗RNase 性质的4S 左右的小分子是其抑制作用的效应成份之一。H_(22)TuRNA 尚可抑制淋巴细胞的粘附能力,提示其可能通过影响淋巴细胞与靶细胞之间的互相接触而表现出对淋巴细胞细胞毒功能的抑制。

THE IN VITRO EFFECT OF RNA FROM H_(22)TUMOR CELLS ON THE CYTOTOXICITY OF LYMPHOCYTES OF NORMAL MOUSE SPLEEN

With the cell-mediated ~(51)Cr release cytotoxicity assay,it was demonstrated that the RNA extracted from H_(22)tumor cells of mouse(H_(22)TuRNA)could significantly inhibit the cytotoxic effect of lymphocytes of normal mouse spleen when the lymphocytes were incubated with H_(22)TuRNA at a dosage of ≥250μg H_(22)TuRNA/1×10~7 lymphocytes and at 37℃ for 60 minutes.This inhibition was dependent on both the incubation time with and the dose of H_(22)TuRNA. The ability of H_(22)TuRNA to inhibit the cytotoxic effect of lymphocytes was not lost by treating with bovine pancreatic RNase.Polyacylamide gel electrophoresis showed that only small molecular RNAs about 4S left after the treatment with the RNase.From this result,it could be said that these small molecular RNAs possessing the anti-RNase property were some of the active factors in H_(22)TuRNA. H_(22)TuRNA could also inhibit the ability of lymphocytes to adhere on glass surfaces. This suggested that the function of H_(22)TuRNA to inhibit the cytotoxic effect of lympho- cytes was by affecting the contect between lymphocytes and target cells.