Thymic OX40 expression discriminates cells undergoing strong responses to selection ligands.
OX40 is a member of the TNF receptor family expressed on activated and regulatory T (Treg) cells. Using an Ox40-cre allele for lineage marking, we found that a subpopulation of naive T cells had also previously expressed OX40 in the thymus. Ox40-cre was induced in a small fraction of thymocytes that were OX40(+), some of which were CD25(high) Treg cell precursors. Thymic OX40 expression distinguished cells experiencing a strong signaling response to positive selection. Naive T cells that had previously expressed OX40 demonstrated a partially activated phenotype that was distinct from that of most naive T cells. The results are consistent with the selection of Treg cells and a minor subpopulation of naive T cells being dependent on strong signaling responses to thymic self ligands.
Klinger
Mark
M
Department of Microbiology and Immunology and.
Kim
Joong Kyu
JK
Chmura
Stephen A
SA
Barczak
Andrea
A
Erle
David J
DJ
Killeen
Nigel
N