Abstract:
:The identity of cells that mediate positive selection of CD8(+) T cells was investigated in two T cell receptor (TCR) transgenic systems. Irradiated beta(2)-microglobulin mutant mice or mice with mutations in both the K(b) and D(b) genes were repopulated with fetal liver cells from class I(+) TCR transgenic mice. In the case of the 2C TCR, mature transgene-expressing CD8(+) T cells appeared in the thymuses of the chimeras and in larger numbers in the peripheral lymphoid organs. These CD8(+) T cells were functional, exhibited a naive, resting phenotype, and were mostly thymus-dependent. Their development depended on donor cell class I expression. These results establish that thymic hematopoietic cells can direct positive selection of CD8(+) T cells expressing a conventional TCR. In contrast, no significant development of HY (male antigen)-TCR(+) CD8(+) T cells was observed in class I(+) into class I-deficient chimeras. These data suggest that successful positive selection directed by hematopoietic cells depends on specific properties of the TCR or its thymic ligands. The possibility that hematopoietic cell-induced, positive selection occurs only with TCRs that exhibit relatively high avidity interactions with selecting ligands in the thymus is discussed.
journal_name
Proc Natl Acad Sci U S Aauthors
Zerrahn J,Volkmann A,Coles MC,Held W,Lemonnier FA,Raulet DHdoi
10.1073/pnas.96.20.11470keywords:
subject
Has Abstractpub_date
1999-09-28 00:00:00pages
11470-5issue
20eissn
0027-8424issn
1091-6490journal_volume
96pub_type
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