Abstract:
:A debate has recently surfaced concerning the degree of precommitment attained by alpha beta and gamma delta T-cell precursors prior to T-cell receptor (TCR) gene rearrangement. It has been suggested that precursors may be precommitted to rearrange either alpha or delta genes, but not both, thus giving rise to alpha beta- and gamma delta-producing T cells, respectively. Alternatively, the precursors may be flexible with regard to potential TCR gene rearrangements. To address this controversy, the gene rearrangements among a group of T-cell hybridomas from fetal, newborn, and early postnatal mouse thymi were examined. Six probes spanning the delta and alpha loci were used in Southern blot analyses to characterize the rearrangements which occurred on homologous chromosomes in each cell. Although homologous chromosomes often rearranged in synchrony within the alpha locus, a number of hybridomas were found which had retained a delta rearrangement on one chromosome and an alpha rearrangement on the second. Results show that a precommitment by T cells to rearrange delta or alpha genes in a mutually exclusive manner is not an absolute feature of mouse thymocyte development.
journal_name
Proc Natl Acad Sci U S Aauthors
Thompson SD,Pelkonen J,Hurwitz JLdoi
10.1073/pnas.87.14.5583subject
Has Abstractpub_date
1990-07-01 00:00:00pages
5583-6issue
14eissn
0027-8424issn
1091-6490journal_volume
87pub_type
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