恶性疟原虫复合抗原DNA疫苗诱导小鼠的细胞免疫及体液免疫应答

CELL-MEDIATED AND HUMORAL IMMUNE RESPONSES IN MICE INDUCED BY A MALARIA DNA VACCINE FROM A HYBRID GENE OF ANTIGEN FOR PLASMODIUM FALCIPARUM

目的 观察用恶性疟原虫复合抗原基因 HGFSP构建的 DNA疫苗 pc- HGFSP免疫小鼠诱导的细胞及体液免疫应答。 方法 用 pc- HGFSP肌注免疫 C5 7BL/6小鼠并加强免疫 2次 ,取小鼠脾淋巴细胞及血清测定 :脾淋巴细胞增殖活性 (MTT法 ) ;NK细胞活性和 CTL活性 (L DH法 ) ;脾脏 CD4 +及 CD8+ T细胞亚群 (免疫荧光法 ) ;血清 pc- HGFSP抗原特异性抗体 (EL ISA法 )及一氧化氮 (NO)含量。 结果 与 pc DNA3对照比较 ,pc- HGFSP免疫小鼠脾淋巴细胞增殖活性增高 2 4 %～ 37% ;NK细胞活性增高 38%～ 90 % ;CTL 活性增高 6 5 %～ 15 3% ;CD8+ T细胞亚群增加。免疫血清产生HGFSP抗原特异性 Ig G抗体 ;NO含量也有所增高。 结论 恶性疟 DNA疫苗 pc- HGFSP有一定的诱导小鼠细胞免疫和体液免疫应答的作用。

Objective To observe the cell mediated and humoral immune responses elicited by pc HGFSP, a DNA vaccine constructed from a hybrid gene encoding the epitopes of antigens from MSA1, MSA2, RESA and CSP of Plasmodium falciparum (P.f.) and the T cell epitopes from interleukin 1(IL 1) and tatanus toxin(TT). Methods C57BL/6 mice were inoculated intramuscularly with pc HGFSP plasmid at the dosage of 100 μg in quadriceps muscles. Two booster injections were given at three weeks interval. After the last booster, the spleens and sera of immunized mice were collected for immunological assays, such as the proliferation activity(MTT method), NK cell and CTL activity(LDH method), and the content of the HGFSP antigen specific antibodies(ELISA method). Results Compared with pcDNA 3 control, the proliferation activity, the NK cell activity and the CTL activity in pc HGFSP immunized mice were increased by 24%-37%, 38%-90% and 65%-153%, respectively. The numbers of CD8 + T cells of spleen lymphocytes were increased in pc HGFSP immunized mice. The HGFSP antigen specific IgG antibodies were detected from the sera of pc HGFSP immunized mice. The content of nitric oxide(NO) in the sera of pc HGFSP immunized mice was also increased. Conclusion The malaria DNA vaccine, pc HGFSP, can induce in vivo the cell mediated immune response and humoral immune response in mice.