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The tumor suppressor Tsc1 enforces quiescence of naive T cells to promote immune homeostasis and function.

ABSTRACT: The mechanisms that regulate T cell quiescence are poorly understood. We report that the tumor suppressor Tsc1 established a quiescence program in naive T cells by controlling cell size, cell cycle entry and responses to stimulation of the T cell antigen receptor. Abrogation of quiescence predisposed Tsc1-deficient T cells to apoptosis that resulted in loss of conventional T cells and invariant natural killer T cells. Loss of Tsc1 function dampened in vivo immune responses to bacterial infection. Tsc1-deficient T cells had more activity of the serine-threonine kinase complex mTORC1 but less mTORC2 activity, and activation of mTORC1 was essential for the disruption of immune homeostasis. Therefore, Tsc1-dependent control of mTOR is crucial in actively maintaining the quiescence of naive T cells to facilitate adaptive immune function.

SUBMITTER: Yang K

PROVIDER: S-EPMC3158818 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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The tumor suppressor Tsc1 enforces quiescence of naive T cells to promote immune homeostasis and function.

Yang Kai K Neale Geoffrey G Green Douglas R DR He Weifeng W Chi Hongbo H

Nature immunology 20110717 9

The mechanisms that regulate T cell quiescence are poorly understood. We report that the tumor suppressor Tsc1 established a quiescence program in naive T cells by controlling cell size, cell cycle entry and responses to stimulation of the T cell antigen receptor. Abrogation of quiescence predisposed Tsc1-deficient T cells to apoptosis that resulted in loss of conventional T cells and invariant natural killer T cells. Loss of Tsc1 function dampened in vivo immune responses to bacterial infection ...[more]

PMID: 21765414

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Tuberous sclerosis complex 1 (Tsc1) enforces quiescence of naive T cells to promote immune homeostasis and function

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