This may suggest that neovessels in the B16 microenvironment are MHC class II+ either constitutively or under inflammatory conditions under which IFN-γ is elaborated, that B16 melanomas become class II+ after in vivo transfer or upon provision of IFN-γ in situ, or that the mEphA2 30–44 Th peptide also contains an embedded CTL epitope. The gene discussed is TH; the disease is melanoma.