The viral inhibitory effect on MHC expression was present when the cells were infected with the wild-type TB40E, but not with the virus lacking the US2-11 genes, and infection with ΔUS2-11 virus led to MHC-I levels comparable to (in HFF and M2-Mφ) or even higher (in M1-Mφ) than those of uninfected cells. The gene discussed is HLA-C; the disease is infection.