非特异性酯酶同工酶(x-NAE isoenzyme)活性的异常升高及异常同工酶谱的表达与恶性肿瘤的发生密切相关.抗胃癌生物活性肽是从处理后胃癌细胞诱导的相关动物脾脏中提取出来的一种新型生物学应答调节剂(BRM,Biological respo- nse modifier).实验表明,这一活性物质对胃癌细胞有很强的特异性抑制作用,并能在体内产生多种生物学效应.本文在此研究基础上,进一步探讨了其抗癌效应过程中对x-NAE同工酶代谢的影响,结果表明:体内注射抗胃癌生物活性肽,不仅使荷瘤鼠皮下肿瘤生长显著减慢(P<0.01),同时使x-NAE同工酶谱表型发生明显变化,部分同工酶带型消失.提示:这一抗胃癌生物活性肽对荷瘤小鼠体内x-NAE同工酶蛋白表达及其基因表达产生了明显的生物调节作用.

We have studied the effects of B7-1 on antitumor immunity induced in vivo by murine B7-1 gene transfected EL-4 lymphoma. At a lethal dose of wild - type(wt) or plasmid controlled (pc) B7-1 negative tumor cells. B7-1 gone transfected EL-4 cells inoculated in syngeneic mice were regressed. In contrast to the mice immunized with B7-1 tumor cells, immunization of mice with B7-l~EL-4 tumor cells showed significant protective effects against the sequence rechallenge of wt EL-4 tumor. Vaccination with X-irradiated B7-1 positive tumor cells at the early stage ( 7 days) after inoculation of wt EL-4 tumor cells showed some therapeutically effects but not at the late stage (14 days after inoculation). Vaccination with B7-l~ EL-4 tumor cells delayed the occurrence of wt EL-4 tumors and prolonged the survival period of tumor-bearing mice. Our results indicate that the transfcction of B7-1 into tumor cells can increase the immunogenicity of EL-4 tumor and improve host response to wt EL-4 lymphoma. Immunization with B7-1 positive tumors can elicit effective antitumor immunity.

R73－3

国家自然科学基金(39470659)资助课题