Increased number of cytotoxic T cells within CD4+8- T cells in beta 2-microglobulin, major histocompatibility complex class I-deficient mice.
Targeted disruption of beta 2-microglobulin gene results in deficient major histocompatibility complex class I expression and failure to develop CD4-8+ T cells. Despite this, beta 2 M-/- mice reject skin grafts and cope with most viral infections tested. We asked whether CD4+8- cytotoxic T cells would play a role in compensating for the defect in CD4-8+ cytotoxic T cell function. We found that the cytotoxic activity against class II+ targets is significantly higher among CD4+8- T cells of beta 2M-/- than among those of beta 2M+/+ mice. In the limiting dilution experiment, we showed that the precursor frequency for the cytotoxic, CD4+8-, class II-specific T cells is at least fivefold higher in beta 2M-/- than in beta 2M+/+ mice. These results suggest that CD4+8- cytotoxic T cells could play a major role in carrying out cytotoxic function in beta 2M-/- mice.
Marusić-Galesić
S
S
Department of Molecular Medicine, Institute Ruder Bosković, Zagreb.
Udaka
K
K
Walden
P
P
D000818:Animals; D015704:CD4 Antigens / Q000032:analysis*; D016827:CD8 Antigens / Q000032:analysis*; D002454:Cell Differentiation; D006412:Hematopoietic Stem Cells / Q000502:physiology; D015395:Histocompatibility Antigens Class I / Q000032:analysis*; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D013602:T-Lymphocytes, Cytotoxic / Q000502:physiology*; D001613:beta 2-Microglobulin / Q000172:deficiency*
D015704:CD4 Antigens; D016827:CD8 Antigens; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D001613:beta 2-Microglobulin