探讨胎牛肝细胞低分子天然抑瘤物 (LMW NTS)的理化性质、生物学特性、急性与长期毒性作用。方法 :从胎牛肝脏中分离提取出LMW NTS ,用高压液相色谱仪测定其分子量 ,紫外分光光度法测定OD2 6 0 及OD2 80 值。采用体外双层软琼脂细胞培养及腹腔注射LMW NTS治疗荷瘤小鼠 ,观察其体内外抗肿瘤作用、急性与长期毒性作用。结果 :胎牛肝细胞LMW NTS的分子量为 70 0 0～ 80 0 0 ,属核酸和多肽类物质 ,性质稳定。体外培养条件下胎牛肝细胞LMW NTS对小鼠S 180细胞较对正常小鼠骨髓粒 巨噬系祖细胞有更强的抑制增殖及集落生成作用 ;腹腔注射胎牛肝细胞LMW NTS治疗荷瘤小鼠能显著延长小鼠寿命 (P <0 .0 0 1)。毒性试验证实胎牛肝细胞LMW NTS无毒副作用 ,长期应用安全。结论 :胎牛肝细胞LMW NTS是一类分子量小、在体内外均有明显抗肿瘤作用、应用安全可靠的抑瘤物。

Objective: To probe into the physical and chemical property, biology activity,acute and chronic toxicity of low molecular weight natural tumor suppressor (LMW NTS)of fetal bovine hepatocytes. Methods: LMW NTS was isolated from fetal bovine hepatocytes and its molecular weight was measured by high pressure liquid chromatography, the ratio of OD 260 /OD 280 was calculated by spectrophotomctry. Anti tumor effects of fetal bovine hepatocytes LMW NTS were investigated by in vitro two layers agar plate cell culture and by tumor bearing mice following the intraperitoneal administration of the fetal bovine hepatocytes LMW NTS. Results: The fetal bovine hepatocytes LMW NTS had approximate molecular weight of about 7 000~8 000 and belonged to low molecular weight ribonucleic acid and peptide. Under the condition of in vitro agar plate culture, the LMW NTS of fetal bovine hepatocytes showed remarkable inhibitory effects on the growth of murine S 180 cells, but weaker effects on the growth of normal murine bone marrow granulocyte macrophage progenitors. Survival period of the S 180 cells bearing mice treated with intraperitoneal injection of the fetal bovine hepatocytes LMW NTS was strikingly prolonged( P <0.001). Toxicity test proved that the fetal bovine hepatocytes LMW NTS had no side effects and was safe for long time application. Conclusion: The LMW NTS of fetal bovine hepatocytes possesses the property of low molecular weight and striking anti tumor activities both in vitro and in vivo.

广西自然科学基金项目（桂攻科9635090）