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Onset of TCR-beta gene rearrangement and role of TCR-beta expression during CD3-CD4-CD8- thymocyte differentiation

Authors :
D I Godfrey
J Kennedy
P Mombaerts
S Tonegawa
A Zlotnik
Source :
The Journal of Immunology. 152:4783-4792
Publication Year :
1994
Publisher :
The American Association of Immunologists, 1994.

Abstract

TCR-beta gene rearrangement or expression is necessary and sufficient for the progression of early alpha beta thymocyte differentiation from the CD3-CD4-CD8- triple negative (TN)3 to the CD4+CD8+ double positive stage. The onset of TCR-beta rearrangement is currently thought to occur gradually. Some thymocytes were reported to be rearranged at the earliest (CD44+CD25-) TN stage, whereas other thymocytes did not initiate TCR-beta rearrangement until the latest (CD44-CD25-) TN stage. Here, we have isolated subsets of TN thymocytes on the basis of surface expression of CD44 and CD25, with c-kit as an additional marker. We present a revised model of early T cell development in which TCR-beta and TCR-gamma rearrangements occur abruptly, at the CD44lowCD25+ c-kitlowTN stage. A high level of c-kit expression defines pro-T cells which have not yet rearranged their TCR genes. Germ-line TCR-beta transcripts, and transcripts of recombination activating genes (RAG)-1 and 2, are detected before TCR-beta gene rearrangement. Analyses of TN thymocytes of RAG-1 mutant mice, and of various TCR mutant and TCR transgenic RAG-1 mutant mice, indicate the existence of a control point at the CD44-CD25+TN stage at which cells expressing a productively rearranged TCR-beta chain are selected for further differentiation.

Subjects

Subjects :
Immunology
Immunology and Allergy

Details

ISSN :
15506606 and 00221767
Volume :
152
Database :
OpenAIRE
Journal :
The Journal of Immunology
Accession number :
edsair.doi...........c23844e5b5712866135033589c670b3f