Differential effect of adenovirus 2 E3/19K glycoprotein on the expression of H-2K b and H-2D b class I antigens and H-2K b- and H-2D b-restricted SV40-specific CTL-mediated lysis

Abstract

The E3/19-kDa glycoprotein (E3/19K) coded by adenovirus type 2 (Ad2) is known to inhibit the cell-surface expression of major histocompatibility complex (MHC) class I antigens by binding to the MHC antigens intracellularly, and thus reduces recognition of antigens by MHC-restricted cytotoxic T lymphocytes (CTL). We have studied the effect of the E3/19K expression in SV40-infected monkey cells, TC-7/H-2K b and TC-7/H-2D b expressing transfected H-2K b and H-2D b antigens, respectively, on the cell-surface H-2 class I antigens and on lysis of the cells by SV40 large tumor (T)-antigen-specific H-2K b- and H-2D b-restricted CTL clones. H-2D b antigen expression on TC-7/H-2D b cells was drastically reduced by infection with Ad2 but not with an E3/19K-negative SV40-Ad2 hybrid virus, Ad2 +ND1, as early as 12 hr postinfection. However, H-2K b antigen expression on Ad2-infected TC7/H-2K b cells remained unaltered, even at 24 hr postinfection. Specific lysis of SV40-infected TC-7/H-2D b cells by H-2D b-restricted SV40 T-antigen-specific CTL clones, Y-1 and Y-3, was strongly reduced by coinfection of the target cells with Ad2 but not with Ad2 +ND1. Lysis of SV40-infected TC-7/H-2K b cells by a H-2K b-restricted SV40 T-antigen-specific CTL clone Y-4 was also reduced significantly by Ad2 infection, but not Ad2 +ND1. These results indicate that the E3/19K protein affects cell-surface expression of H-2D b antigen but not H-2K b antigen.