RESUMO
Objective:As a promising strategy,tumor vaccine is at the forefront of novel approaches to tumor treatment.Since tumor antigens derived from self proteins are often less immunogenic alone,they must be administered with a potent immunostimulatory adjuvant to induce robust T-cell response.IFA was widely used and considered to be one of the most effective adjuvant available for con-sistently producing high titer antibodies to diverse antigens.However,IFA-containing tumor vaccines do not produce positive results.The reasons are unclear.Methods:BALB/c mice were s.c.injected with one single dose of IFA.At indicated days, spleen cells were collected and detected for CD11b+cells.MTT method was used to analyze the effect of CD11b+cells on T cell proliferation.ELISA method was used to determine the influence of CD11b+cell on IFN-γ-secreting ability of T cells.Results:In the spleen of mice treated with IFA,the proportion of CD11b+cell was augmented.IFA-induced CD11b+cells inhibit the proliferation and tumor antigen-induced IFN-γ-secreting ability of T cells.Conclusion:This finding may help to understand the low therapeutic efficacy of cancer vaccines recently observed in some clinical trials using Freund′s adjuvant and underscores the necessity of adjuvant selection for active immuno-therapy.