结核分枝杆菌Rv2450蛋白诱导小鼠免疫应答的实验研究

目的:以原核表达的结核分枝杆菌Rv2450蛋白在小鼠体内诱导体液和细胞免疫应答。方法:采用皮下包埋的方法,以预先转移到硝酸纤维素膜上的原核表达的Rv2450蛋白免疫小鼠(10只)3次,每次间隔2周。用间接ELISA法检测免疫小鼠血清特异性抗体的滴度。末次免疫完成后4周,处死3只免疫小鼠并分离脾淋巴细胞,体外经PPD(2μg/孔)刺激后,用MTT比色法检测免疫小鼠脾淋巴细胞的增殖指数。用ELISA法检测脾淋巴细胞悬液中IFN-γ、IL-10及IL-12的水平。结果:Rv2450蛋白免疫小鼠血清特异性抗体的滴度为1∶3200,淋巴细胞增殖指数为3.76±0.19。免疫小鼠脾淋巴细胞培养液中IFN-γ、IL-10及IL-12的含量,分别为(1740±19)ng/L、(678±15)ng/L、(469±13)ng/L,均高于各组的生理盐水对照组(P<0.05)。结论:Rv2450有可能作为新型结核疫苗的候选组分。

Immune response induced by Mycobacterium tuberculosis Rv2450 protein in mice

AIM: To evaluate humoral and cellular immune response induced by Rv2450 protein. METHODS: Rv2450 protein was transferred to membrane and used to immunize C57BL/6 mice three times at 2 week interval. The spleen lymphocytes of the immunized mice were separated and the stimulation index (SI) was measured by MTT colorimetry and the levels of secreted IFN-gamma, IL-10 and IL-12 upon antigen-specific stimulation was detected by ELISA. RESULTS: The titer of specific antibody in sera of the immunized C57BL/6 mice was 1:3 200. The SI of Rv2450 protein immunized group (3.76 +/- 0.19) was significantly higher than that of saline immunized group (0.89+/-0.17). The IFN-gamma, IL-10, IL-12 levels in culture supernatant of spleen lymphocytes from the immunized mice was (1 740 +/- 19) ng/L, (678 +/- 15) ng/L and (469 +/- 13) ng/L respectively, significantly different from that of saline-immunized group. CONCLUSION: Rv2450 protein can be used as a candidate for the new TB vaccine.