Cutting Edge: memory regulatory t cells require IL-7 and not IL-2 for their maintenance in peripheral tissues

IK Gratz, HA Truong, SHY Yang… - The Journal of …, 2013 - journals.aai.org
IK Gratz, HA Truong, SHY Yang, MM Maurano, K Lee, AK Abbas, MD Rosenblum
The Journal of Immunology, 2013journals.aai.org
Thymic Foxp3-expressing regulatory T cells are activated by peripheral self-antigen to
increase their suppressive function, and a fraction of these cells survive as memory
regulatory T cells (mTregs). mTregs persist in nonlymphoid tissue after cessation of Ag
expression and have enhanced capacity to suppress tissue-specific autoimmunity. In this
study, we show that murine mTregs express specific effector memory T cell markers and
localize preferentially to hair follicles in skin. Memory Tregs express high levels of both IL …
Abstract
Thymic Foxp3-expressing regulatory T cells are activated by peripheral self-antigen to increase their suppressive function, and a fraction of these cells survive as memory regulatory T cells (mTregs). mTregs persist in nonlymphoid tissue after cessation of Ag expression and have enhanced capacity to suppress tissue-specific autoimmunity. In this study, we show that murine mTregs express specific effector memory T cell markers and localize preferentially to hair follicles in skin. Memory Tregs express high levels of both IL-2Rα and IL-7Rα. Using a genetic-deletion approach, we show that IL-2 is required to generate mTregs from naive CD4+ T cell precursors in vivo. However, IL-2 is not required to maintain these cells in the skin and skin-draining lymph nodes. Conversely, IL-7 is essential for maintaining mTregs in skin in the steady state. These results elucidate the fundamental biology of mTregs and show that IL-7 plays an important role in their survival in skin.
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