068 Pathogenic Th17 cells, CD8+CD69+CD49a- tissue-resident memory T cells and common γ chain receptor + natural killer cells express more IL-17, compared to IFN-γ, under the foxp3+ memory regulatory T cells-depleted microenvironment in patients with chronic alopecia areata

Alopecia areata (AA) is an organ-specific autoimmune disease resulting from the attack of hair follicle (HF) autoantigens through a T-cell-mediated mechanism. If there depletion mTregs in HFs, especially around both bulge and bulb, it could be related to patchy loss scalp may affect AA pathogenesis. Here, we investigated possible contributory role tissue-resident memory T cells (TRMs) regulatory (mTregs), compared cytotoxic lymphocytes Th17 lymphocytes, immunopathogenesis chronic AA. The number lesional Foxp3+ Tregs was significantly decreased with increase severity histopathological gradings at following order: Type 1 > type 2 3 lesions. We postulated that CD8+CD69+CD49a- TRM are responsible for development lesions under influence HF perifollicular intrafollicular microenvironments. CD8+CD69+ bulb increased grade. As expression profile effector cells, IL-17 expressed denser pattern more severe grading, but IFN-γ only Lesional also In contrast, conclusion, insidious destruction stem matrix which mediated by Th17lymphocytes lymphocyte infiltration, results patients play important pathogenesis than IFN-γ.