ISSN:
1365-3083
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
We have recently generated 5′λ5-huTAC mice, which express the human CD25 (huTAC) gene under the control of the 5′-flanking region of the mouse λ5-gene. The huTAC-transgene was expressed in pre-B cells but neither in mature B cells nor in T cells of these mice. In this report we demonstrate that the transgene is also transiently expressed by adult CD25+ CD3−CD4−CD8− (triple negative, TN) thymocytes and in fetal thymocytes. The huTAC+, in contrast to the huTAC− subpopulation of the CD44+CD25+ TN cells, was unexpectedly found not to express the pTα-gene. Still the huTAC+CD44+CD25+ TN cells reconstituted the development of both αβ and γδ lineage cells equally efficiently as the pTα-expressing huTAC− fraction, demonstrating that this pTα-negative subpopulation contained precursors for both T-cell lineages. Single cell reverse transcription–polymerase chain reaction (RT–PCR) experiments demonstrated that also in normal mice only a fraction of CD44+CD25+ and CD44−CD25+ TN cells expressed this gene. Taken together, these data indicate that huTAC transgene expression revealed a truly pTα-negative fraction of the CD44+CD25+ TN cells. The observation that not all precursors in the CD25+ TN population express the pTα-gene has important implications for the understanding of early T-cell development and T-cell lineage commitment.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-3083.2002.01022.x
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