To evaluate whether the BXLF2 gene of Epstein-Barr virus (EBV), which codes gp85 protein, is essential for infection of B cells and epithelial cells, we analyzed the infectivity of an EBV recombinant lacking gp85. The cells that were infected with the BXLF2-disrupted virus were unable to express gp85 proteins that could be detected by mouse monoclonal antibody E1D1, specific for gp85/gp25 complexes. The BXLF2-disrupted EBV had the ability to attach to, but not infect, B cells. On the other hand, the same virus failed to bind to and infect NU-GC-3, a human gastric adenocarcinoma cell line that is susceptible to EBV infection. The results indicate that the gp85 is used for infection of not only B cells but also epithelial cells and suggest that the gp85 is necessary for attaching the virus to epithelial cells.
Copyright 2000 Academic Press.