Cutting Edge: Memory Regulatory T Cells Require IL-7 and Not IL-2 for Their Maintenance in Peripheral Tissues

The study demonstrated that memory regulatory T cells (mTregs) in mice, which are crucial for suppressing tissue-specific autoimmunity, required IL-2 for their initial generation from naive CD4+ T cells but not for their maintenance in peripheral tissues such as skin and skin-draining lymph nodes. Instead, IL-7 was essential for the survival of mTregs in the skin. The findings highlighted the distinct roles of IL-2 and IL-7 in the lifecycle of mTregs, with IL-7 being particularly important for their persistence in nonlymphoid tissues.