Research ArticleImmunology

The Long-Term Survival Potential of Mature T Lymphocytes Is Programmed During Development in the Thymus

Science Signaling  15 Nov 2011:
Vol. 4, Issue 199, pp. ra77
DOI: 10.1126/scisignal.2002246

You are currently viewing the editor's summary.

View Full Text
As a service to the community, AAAS/Science has made this article free with registration.

Programming T Cell Survival

The development of thymocytes in the thymus critically depends on signals through the T cell antigen receptor (TCR) and the receptor for the homeostatic cytokine interleukin-7 (IL-7). During development, thymocytes lose IL-7Rα but regain the receptor after they receive signals through the TCR in a process known as positive selection. When thymocytes leave the thymus as mature T lymphocytes and move to peripheral lymphoid organs, they still depend on TCR and IL-7R signaling for their survival. Sinclair et al. found that TCR signaling in developing thymocytes in the mouse activated the reexpression of Il7r and the reappearance of IL-7Rα on the cell surface. The abundance of surface IL-7Rα correlated with the strength of positive selection, and those T cells with the highest abundance of IL-7Rα had the greatest chance of survival in the periphery. In contrast, TCR signaling in peripheral T cells did not alter the abundance or function of IL-7Rα. Together, these data suggest that TCR-dependent regulation of IL-7Rα abundance on thymocytes determines the long-term survivability of the resulting T cells.