CD4 and neoplasm: We found that vaccination with irradiated B16-mBD2, but not with control B16 or B16-p cells, inhibited the development and progression of melanoma and prolonged the survival of tumor-bearing mice, which was accompanied by inducing potent NK activity, melanoma-specific CTL responses, and IFN-γ and IL-12 production as well as CD8+ T, CD4+ T, macrophage and NK cell infiltration in the tumor tissues.