关键词: 恶性疟原虫, 富组氨酸蛋白-2(HRP-Ⅱ), DNA疫苗, 免疫反应

Abstract: 　Objective] To explore the humoral and cellular immune responses in mice to eukaryotic expression recombinant plasmid encoding histidine rich protein 2 (HRP-Ⅱ) of Plasmodium falciparum. [Methods] The start and stop codes were introduced into HRP-Ⅱ gene fragment, the reading frame and the position of start and stop codes in HRP-Ⅱ were identified by sequencing. HRP-Ⅱ fragment containing the start and stop codes was cloned into pcDNA3 1(-) to form pcDNA3 1(-)/HRP-Ⅱ. The BALB/c mice were immunized i.m. with the plasmids for 3 times in 3 weeks intervals. Two weeks after the last immunization, the sera and splenocytes were collected to investigate anti-HRP-Ⅱ antibodies by ELISA and the splenocytes proliferation response to HRP-Ⅱ. [Results] Sequence data show that the reading frame and the position of start and stop codes are correct. Restriction enzyme digestion indicated that the HRP-Ⅱ gene fragment containing start and stop codes was successfully cloned into pcDNA3 1(-). Mice raised significant anti-HRP-Ⅱ antibodies after pcDNA3 1(-)/HRP-Ⅱ immunization, and the splenocytes proliferated prominently when stimulated with HRP-Ⅱ protein. [Conclusion] Eukaryotic expression recombinant plasmid \{encoding\} HRP-Ⅱ gene can induce significantly humoral and cellular immune response in mice. HRP-Ⅱ gene may be a good candidate for P.falciparum blood-stage multiple DNA vaccine.

Key words: Plasmodium falciparum, histidine rich protein 2(HRP-Ⅱ), DNA vaccine, immune response