Quantitative and qualitative adjustment of thymic T cell production by clonal expansion of premigrant thymocytes.
In normal mice, single-positive thymocytes proliferate before being exported into the peripheral T cell pool. We measured the in vivo proliferation rates of mature thymocytes in several TCR transgenic mice. Different monoclonal TCR transgenic single-positive thymocytes proliferated at different rates in a given MHC context. Conversely, mature thymocytes expressing a given TCR, generated in mice of different MHC haplotypes, also showed different rates of proliferation. In p59(fyn)-deficient mice, the proliferation rate of mature thymocytes was diminished. Thus, premigrant thymocyte expansion is TCR mediated and depends on TCR affinity for self peptide/MHC ligands. In addition, we show that mature thymocyte expansion is clonotypic, increases the daily thymic T cell output, and modifies the TCR repertoire of newly produced T cells.
Le Campion
Armelle
A
Institut National de la Santé et de la Recherche Médicale Unité 345 and Laboratoire d'Expérimentation Animale et de Transgénèse, Institut Necker, Paris, France. lecampio@necker.fr
Lucas
Bruno
B
Dautigny
Nicole
N
Léaument
Sandrine
S
Vasseur
Florence
F
Pénit
Claude
C
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002465:Cell Movement; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D005434:Flow Cytometry; D006183:H-2 Antigens / Q000502:physiology; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000502:physiology; D051076:Proto-Oncogene Proteins c-fyn; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics; D016176:T-Lymphocyte Subsets / Q000145:classification / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology*
D004268:DNA-Binding Proteins; D006183:H-2 Antigens; D011518:Proto-Oncogene Proteins; C499308:Rag2 protein, mouse; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; C064655:V(D)J recombination activating protein 2; C494960:Fyn protein, mouse; D051076:Proto-Oncogene Proteins c-fyn