title: Biased V beta usage in immature thymocytes is independent of DJ beta proximity and pT alpha pairing.
abstract: During thymus development, the TCR beta locus rearranges before the TCR alpha locus. Pairing of productively rearranged TCR beta-chains with an invariant pT alpha chain leads to the formation of a pre-TCR and subsequent expansion of immature pre-T cells. Essentially nothing is known about the TCR V beta repertoire in pre-T cells before or after the expression of a pre-TCR. Using intracellular staining, we show here that the TCR V beta repertoire is significantly biased at the earliest developmental stage in which VDJ beta rearrangement has occurred. Moreover (and in contrast to the V(H) repertoire in immature B cells), V beta repertoire biases in immature T cells do not reflect proximity of V beta gene segments to the DJ beta cluster, nor do they depend upon preferential V beta pairing with the pT alpha chain. We conclude that V gene repertoires in developing T and B cells are controlled by partially distinct mechanisms.
authors: Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Epalinges, Switzerland.
authors: A
authors: A
authors: Wilson
authors: C
authors: C
authors: Maréchal
authors: H R
authors: HR
authors: MacDonald
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D002455:Cell Division / Q000235:genetics / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D015332:Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D007424:Intracellular Fluid / Q000276:immunology / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D005810:Multigene Family / Q000235:genetics / Q000276:immunology; D011498:Protein Precursors / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D013194:Staining and Labeling; D013601:T-Lymphocytes / Q000737:chemistry / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D013950:Thymus Gland / Q000737:chemistry / Q000166:cytology / Q000276:immunology / Q000378:metabolism*
chemical_list: D008562:Membrane Glycoproteins; D011498:Protein Precursors; D016693:Receptors, Antigen, T-Cell, alpha-beta; C090377:pre-T cell receptor alpha