Differential lack of class I H-2(d) antigen expression by sublines of the BALB/c S49 T cell lymphoma

Five different sublines of the BALB/c murine S49.1 T cell lymphoma were found to exhibit distinct patterns of absence of detectable H-2(d) class I major histocompatibility antigen expression. The results were demonstrated and verified by a) the generation of H-2K(d)-, H-2D(d),L(d)-, and H-2L(d)-specific cytotoxic T lymphocytes that were assayed on S49.1 target cell lines, b) antibody-mediated cytotoxicity with the use of anti-H-2(d) monoclonal reagents, and c) flow microfluorometry. The five lines investigated were S49.1, T-25, T-25ADH, Thy-1^-, and 100/0. None of these lines expressed detectable levels of L(d). S49.1 expressed both K(d) and D(d), T-25 and T-25ADH expressed D(d) but not K(d) or L(d), Thy-1^- expressed K(d) but not D(d) or L(d), and 100/0 did not express any detectable amounts of K(d), D(d), or L(d). These results indicate that K and D (and L) antigens can be expressed independently of each other and suggest that expression of class I antigens is controlled in a locus-specific manner.