Abstract: Objective To investigate the formulations of Plasmodium falciparum polyepitope chimeric vaccine M.RCAg-1 & M.RCAg-3 with different adjuvants in order to increase their immunogenicities and to find out their basic immune mechanisms. Methods The polyepitope chimeric vaccines formulated with different adjuvants (AD, ADL, CpG, CpG&Al) were injected subcutaneously into mice for three times. The immunization was performed on week 0, 2, 4. The concentration of anti-M.RCAg-1 and anti-M.RCAg-3 IgG, the IgG isotype and the recognition level with M.RCAg-1/M.RCAg-3 single epitopes were detected at ten days after week 4. The recognition of antibodies in serum was tested with indirect immunofluorescence assay (IFA). Results We showed here that ADL and AD can enhance the immunogenicities of M.RCAg-1 and M.RCAg-3 respectively. Compared with another groups, ADL and AD formulated with M.RCAg-1 and M.RCAg-3 respectively can enhance their antibodies recognition with natural parasites greatly. Their antibodies can recognize the single epitopes generally. Conclusion ADL and AD can greatly increase the immunization antibody level of M.RCAg-1 and M.RCAg-3 and their recognition with natural parasites. In conclusion, ADL and AD, as potential adjuvants, paved the way for the clinical use of M.RCAg-1 and M.RCAg-3 respectively.

Key words: Plasmodium falciparum, polyepitope chimeric vaccine, adjuvants formulation