| Abstract: |
Most murine thymocytes and mature T cells originate from a numerically minor population of CD8−4− (double‐negative, DN) thymocytes. In this study, we investigated the effects of rearranged T cell receptor (TcR) α and β transgenes on early T cell development. We analyzed the precursor potential, the expression of CD25 and TcR at mRNA and/or protein level in DN thymocyte subsets in TcR transgenic (Tg) mice. We report the following observations: (i) despite a large overrepresentation of total DN cells in TcR Tg mice, precursor‐containing CD25+ DN and CD810410 thymocytes are reduced to a third of the nontransgenic control numbers; (ii) like in the normal mice, CD25+ DN and CD810410 can, and TcR+ DN cells cannot generate other thymic subsets; (iii) TcR α mRNA and TcR α/β protein levels are quantitatively increased, but their developmental expression is similar to that in normal mice; and (iv) surface TcR αβ expression becomes detectable as the thymocytes down‐regulate CD25, paralleling the situation in normal mice. Our findings implicate stringent transcriptional control, rather than TcR gene rearrangement, as a decisive regulator of TcR αβ expression in early ontogeny. Copyright © 1993 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim |
| Keywords: |
controlled study; nonhuman; flow cytometry; polymerase chain reaction; cd8 antigen; animal cell; mouse; animal; mice; gene expression; cell maturation; protein; genetic transcription; cell differentiation; transgenic mouse; mice, transgenic; stem cell; t lymphocyte receptor beta chain; gene rearrangement; molecular sequence data; thymus gland; messenger rna; rna, messenger; base sequence; gene control; down regulation; t-lymphocyte subsets; cd4 antigen; protein determination; thymocyte; t lymphocyte subpopulation; receptors, antigen, t-cell, alpha-beta; transgenic mice; oligodeoxyribonucleotides; t lymphocyte receptor alpha chain; ontogeny; interleukin 2 receptor; t cell receptor; t cell development; t lymphocyte receptor gene; female; priority journal; article; gene rearrangement, alpha-chain t-cell antigen receptor; support, non-u.s. gov't; support, u.s. gov't, p.h.s.; gene rearrangement, beta-chain t-cell antigen receptor; cd8−4− thymocytes
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