Developmental potential of CD4-8- thymocytes. Peripheral progeny include mature CD4-8- T cells bearing alpha beta T cell receptor.
We have used the intra-thymic transfer system to investigate the population dynamics of thymocyte and mature T cell subsets in the absence of continuing precursor input from the bone marrow. We have followed the development and life span of CD4+ and CD8+ thymocyte subsets and mature peripheral T cells from intra-thymically injected adult or fetal CD4-8- thymic precursors. Both precursor types proliferated, differentiated, and exported to peripheral lymphoid tissues alpha beta-TCR+CD4+8- and CD4-8+ progeny which formed a stable, long-lived component of the peripheral T cell pool. The production of phenotypically mature thymocytes and peripheral T cells occurred more rapidly from fetal CD4-8- precursors. CD4+8-:CD4-8+ ratios among peripheral progeny of intra-thymically-injected CD4-8- precursors were initially normal, but they steadily declined among progeny of the fetal precursors. Thus, there appear to be differences in the life span and/or proliferative capacity of mature T cells derived from embryonic vs adult progenitors. In addition to the predominant CD4+8- and CD4-8+ subsets of peripheral T cells, a minor (1 to 20%) population of Thy-1+CD3+4-8- T cells was identified among peripheral progeny of intra-thymically-injected CD4-8- thymocytes, as well as in lymph nodes of unmanipulated animals. A total of 20 to 34% of this subset expressed V beta 8+ TCR and the majority were CD5hi, Pgp-1+, and J11d-. The function and specificity of this newly identified population of thymically derived peripheral T cells remains to be investigated.
Guidos
C J
CJ
Department of Pathology, Stanford University School of Medicine, CA 94305.
Weissman
I L
IL
Adkins
B
B
D000375:Aging; D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte; D002454:Cell Differentiation; D005333:Fetus; D007700:Kinetics; D008198:Lymph Nodes / Q000254:growth & development / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D010641:Phenotype; D011948:Receptors, Antigen, T-Cell; D013234:Stem Cells / Q000502:physiology; D013601:T-Lymphocytes / Q000145:classification / Q000502:physiology* / Q000637:transplantation; D013950:Thymus Gland / Q000254:growth & development / Q000502:physiology
D000945:Antigens, Differentiation, T-Lymphocyte; D011948:Receptors, Antigen, T-Cell