EB病毒融合基因Z2A重组BCG的免疫学特性研究

目的对EB病毒融合基因Z2A构建的重组BCG进行鉴定及免疫学研究。方法采用Westernblot方法检测重组BCG中Z2A基因的表达；用重组BCG免疫小鼠，用ELIsA方法检测小鼠血清特异性抗体水平，采用乳酸脱氢酶法检测小鼠的细胞免疫水平，评价重组BCG的免疫效果。结果重组BCG表达的蛋白能被血清BZLFl抗体（或LMP2A抗体）识别；ELISA检测表明，重组BCG能刺激机体产生抗体，当重组BCG细菌数为5×10-8个／只时，抗体滴度最高为17600（186．5±6．7Pg／ml）；BCG对照组及PBS对照组对GT39细胞的杀伤率分别为（32．5±2．7）％和（22．8±2．3）％，重组BCG组为（62．7±6．2）％，差异有统计学意义（P〈0．05）。结论EB病毒融合基因Z2A重组BCG免疫效果良好，能刺激小鼠产生体液免疫和细胞免疫反应。

Immunological characterization of rBCG of the EB virus fusion gene Z2A

Objectives To identify the BZLF1 and LMP2A fusion gene of the EB virus and use recombinant BCG （rB- CG） in an immunologic study. Methods Western blotting was used to detect Z2A gene expression by rBCG, ELISA was used to analyze antibodies in response to rBCG stimulation in mice, and a lactate dehydrogenase assay was used to de- tect cellular immunity, and the effectiveness of immunization with rBCG was analyzed. Results Results showed that the rBCG proteins were recognized by serum antibodies against BZLF1 （LMP2A）. ELISA showed that rBCG stimulated the generation of antibodies. When the number of rBCG cells totalled 5× 10s cells/mouse, the maximum antibody titer was 17 600 （186.5±6. 7） pg/ ml. Cytotoxic T-lymphocytes （CTL） induced by immunization with rBCG killed EBV positive tumor cells at a rate （%） of 62.7±6.2% while CTL induced by immunization with BCG only killed tumor cells at a rate of 32.5±2.7O/oo and CTL induced by immunization with PBS only killed tumor cells at a rate of 22.8±2.3% （P〈0.05）. Conclusion A fusion gene was successfully constructed. In mice, rBCG stimulates humoral and cellular immune func- tion.