Skin-resident CXCR6(+) memory CD4(+) T cells and dendritic cells form dermal perivascular hubs that drive relapse in allergic dermatitis.

CXCR6(+) CD4(+) tissue-resident memory T cells form perivascular clusters with dendritic cells that drive relapse in allergic dermatitis.

• Why it matters: Understanding how pathogenic T cell subsets are maintained and promote relapse is critical for developing targeted therapies for allergic skin conditions, which often recur despite treatment.
• What they did: Researchers identified a CXCR6(+) subpopulation within CD4(+) T RM cells across multiple dermatitis models and demonstrated that CXCL16-dependent interactions with CD301b+ cDC2s support their maintenance; they also showed that blocking CXCL16-CXCR6 signaling impairs these cells' proliferation.
• The result: CXCR6(+) CD4(+) T RM cells persist in human atopic dermatitis even after therapy, indicating they serve as a reservoir for chronic inflammation and highlighting the CXCL16-CXCR6 axis as a potential therapeutic target to prevent relapse.