Comparison of the capacity of murine and human class I MHC molecules to stimulate T cell activation.
The mechanism underlying the apparent differences in the capacity of murine and human class I MHC molecules to function as signal transducing structures in T cells was examined. Cross-linking murine class I MHC molecules on splenic T cells did not stimulate an increase in intracellular calcium ([Ca2+]i) and failed to induce proliferation in the presence of IL-2 or PMA. In contrast, modest proliferation was induced by cross-linking class I MHC molecules on murine peripheral blood T cells or human class I MHC molecules on murine transgenic spleen cells, but only when costimulated with PMA. Moreover, cross-linking murine class I MHC molecules or the human HLA-B27 molecule on T cell lines generated from transgenic murine splenic T cells stimulated only modest proliferation in the presence of PMA, but not IL-2. On the other hand, cross-linking murine class I MHC molecules expressed by the human T cell leukemic line, Jurkat, transfected with genes for these molecules, generated a prompt increase in [Ca2+]i, and stimulated IL-2 production in the presence of PMA. The results demonstrate that both murine and human class I MHC molecules have the capacity to function as signal transducing structures, but that murine T cells are much less responsive to this signal.
Gur
H
H
Harold C. Simmons Arthritis Research Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas 75235.
Wacholtz
M C
MC
Lie
W R
WR
Lipsky
P E
PE
Geppert
T D
TD
D000595:Amino Acid Sequence; D000818:Animals; D002118:Calcium / Q000378:metabolism; D015395:Histocompatibility Antigens Class I / Q000502:physiology*; D006801:Humans; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D051379:Mice; D008969:Molecular Sequence Data; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014162:Transfection
D015395:Histocompatibility Antigens Class I; D007376:Interleukin-2; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium