title: Modulation of Tthy alloantigen expression in the neonatal mouse. The Tthy-bearing thymocyte is a precursor for the peripheral cells expressing Tind and Tsu.
abstract: The T cell alloantigen Tthyd appears on a subpopulation of thymocytes in mice bearing the Igh-1d or e heavy chain haplotype. Ontogenetic studies have suggested that this antigen precedes the appearance of two other T cell alloantigens in the same linkage group, Tindd and Tsud. The purpose of this study was to determine if the Tthy-bearing cell is a precursor for cells in the periphery expressing Tind and Tsu. CAL-20 mice were treated at 48-h intervals beginning on the day of birth with a monoclonal antibody recognizing Tthy. Tthy alloantigen expression, monitored by cytotoxicity assays, was found to be significantly depressed in the thymuses of treated animals; Tind and Tsu also failed to appear in the periphery. Treatment with anti-Tthy caused no significant changes in frequency or surface intensity in the expression of surface Ig. Thy-1.2, Thy-1.2, and Lyt-2.2, as studied by cytofluorograph analysis. We conclude that the T-thyd-bearing cells in the thymus represent a subpopulation that may be a precursor for Tindd- and Tsud-bearing cells. However, Tthyd-bearing cells are more mature than the Thy-1.2 common T cell precursor, pre-T.
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000276:immunology; D000911:Antibodies, Monoclonal; D000950:Antigens, Ly / Q000276:immunology; D000954:Antigens, Surface / Q000276:immunology*; D002454:Cell Differentiation; D007518:Isoantibodies; D051379:Mice; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D018800:Thy-1 Antigens; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000950:Antigens, Ly; D000954:Antigens, Surface; D007518:Isoantibodies; D011948:Receptors, Antigen, T-Cell; D018800:Thy-1 Antigens