SYNTHESIS OF MULTIPLE ANTIGENIC PEPTIDE VACCINES CONTAINING TWO DIFFERENT SCHISTOSOMAL ANTIGENIC PEPTIDES AND THEIR PROTECTIVE EFFECTS ON BALB/c MICE

AIM　Three multiple antigenic peptide(MAP) vaccines, (P₁₁₆)₄(P₂₆)₄-MAP, (P₁₁₆)₄(P₁₄₁)₄-MAP and (P₂₆)₄(J₁₈₇)₄-MAP, in which P₂₆, P₁₁₆, and P₁₄₁ are, respectively, the residue 26-43(AAGVDYEDERISFQDWPK), 116-131(PQEEKEKITKEILNGK) and 141-153(ESLKGSTGKLAVG) of 28 KDa glutathione S-tranferase of Schistosoma mansoni(Sm28GST), and J₁₈₇ is the residue 187-202(PQIDKYLKSSKYIAWP) of 26 KDa glutathione S-tranferase of Schistosoma japonicum(Sj26GST), have been designed for examination of their antigenicities, immunogenicities and protective effects on BALB/c mice. METHODS　The multiple antigenic peptide vaccines consisting of two different antigenic peptides have been synthesized using both Boc and Fmoc chemistry and their antigenicities have been tested with dot-ELISA. Mice were bled to test antibody responses after vaccination with the synthetic MAPs, and were infected with Schistosoma japonicum cercariae. Six weeks after infection, the mice were killed to recover adult worms and eggs in the liver. RESULTS AND CONCLUSION　The synthetic MAPs consisting of two different schistosomal antigenic peptides was shown to be bound by both patient and infected-rabbit sera, and were able to elicit antibody responses specific to natural antigen of Schistoma japonicum. Furthermore, BALB/c mice vaccinated with the synthetic MAPs were significantly protected against the challenge infection with Schistosoma japonicun cercaria. Especially, immunization with (P₁₁₆)₄(P₂₆)₄-MAP reduced the worm burden in BALB/c mice by 73.6% and liver eggs by 75.9%. Therefore, it will be useful for the development of effective anti-schistosome vaccine.