OBJECTIVETo construct the Escherichia coli (E. coli) prokaryotic expression system pET9aHPV11L2E7, purify the fusion protein L2E7 and study the immunnogenicity of the protein.

METHODSThe HPV11 L2, E7 coding region was amplified from condyloma acuminata tissue specimen by PCR. The recombinant plazmid pET9aHPV11L2E7 was established and sequenced. Fusion protein L2E7 (553 amino acids) was expressed in host strain BL21 (DE3plus) by IPTG inducing and identified by using SDS-PAGE and Western blotting. Then L2E7 protein purified with CM column was inoculated to Balb/c mice and its cell-mediated and humoral immunnogenicity was assessed by IFN-gamma enzyme-linked immunospot (ELISPOT) and enzyme-linked immunosorbent assay (ELISA).

RESULTSThe E. coli prokaryotic expression system pET9aHPV11L2E7 was established and the purified fusion protein L2E7 was obtained successfully. The mice in vivo experiment indicated that the purified protein L2E7 could induce HPV11E7 specific cell-mediated immune responses and high level HPV L2E7 antibody was detected in serum.

CONCLUSIONThe purified fusion protein L2E7 could induce specific cell-mediated and humoral immune responses. It can be used as a candidate of genital wart immune therapeutic vaccine.