Antitumor Responses Induced by Recombinant Vaccinia Viruses Expressing p53 Antigenic Peptide and B7 / 中国肿瘤生物治疗杂志

ABSTRACT

Objective: To explore antitumor responses induced by recombinant vaccinia viruses expressing a p53 antigenic peptide (rVV p53 M) and enhanced effect of recombinant vaccinia viruses expressing costimulatory molecule B7 (rVV B7). Methods: A 135 Cys to Tyr point mutation p53 transduced P815 mastocytoma (P815 mp53) was used as an experimental tumor and the p53 protein as the model of tumor associated antigen. rVV p53 M and rVV B7 were used as vaccine to test their induction of CTL and antitumor immunity. Results: Immunization of BABL/c mice with rVV p53 M could elicit specific CTLs, which could specifically lyse P815 mp53 cells. Immunization of mice with rVV p53 M could survive a part of mice challenged with 1?10 6 P815 mp53. Treatment with rVV p53 M could significantly prolong the survival of tumor bearing mice. Admixture at 1∶1 ratio of rVV p53 M and rVV B7 could enhance antitumor responses induced by rVV p53 M. Conclusion: Immunization with recombinant vaccinia virus expressing antigenic peptide is a useful alternative to peptide based vaccine. Costimulatory molecule B7 can enhance antigenic peptide to induce antitumor responses.