pTregs
Peripheral regulatory T cells, or pTregs, are a subset of CD4+ regulatory T cells that acquire the transcription factor FOXP3 and regulatory function outside the thymus, in contrast to thymus-derived tTregs (also called nTregs). pTregs originate from conventional CD4+ T cells upon antigen encounter in peripheral tissues, with the gut-associated lymphoid tissue being a prominent site where signals such as transforming growth factor-beta (TGF-β), interleukin-2 (IL-2), and retinoic acid promote FOXP3 induction.
Development and markers: In addition to FOXP3, pTregs commonly express CD25 and CTLA-4. Markers historically used
Function and mechanisms: pTregs suppress effector T cell responses through multiple pathways, including production of anti-inflammatory
Biological and clinical relevance: Disruption of pTreg generation or stability can contribute to inflammatory diseases such