The RVAD65 HCMV strain does not affect the expression of HLA-DR. Fibroblasts infected with AD169, HA, Towne, UL18ΔHCMV, or RVAD765 were examined for the expression of HLA-DR at 1 day after infection. The level of expression of HLA-DR in AD169 (A), HA (B), Towne (C), UL18ΔHCMV (D), RVAD65 (E), or infected cells (black lines) was compared with the HLA-DR expression on uninfected cells (gray lines). Dendritic cells were mock infected or infected with AD169 or RVAD65 and analyzed for the expression of HLA-DR at 1 day after infection (F-G, respectively). Panel H represents the percentage of dendritic cells (±SD) stained positive for HCMV early antigens, where a significantly reduced HLA-DR expression was observed on the infected dendritic cell cultures (MOI 25).