American Society of Hirudotherapy

Regulatory T cells promote innate inflammation after skin barrier breach via TGF- activation

Research article published in Science immunology (2021)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Safety & Infection ControlMoreau JM et al. · Science immunology, 2021

Abstract

Regulatory T cells (Tregs) use multiple mechanisms to attenuate inflammation and prevent autoimmunity. Tregs residing in peripheral (i.e., nonlymphoid) tissues have specialized functions; specifically, skin Tregs promote wound healing, suppress dermal fibrosis, facilitate epidermal regeneration, and augment hair follicle cycling. Here, we demonstrated that skin Tregs were transcriptionally attuned to interact with their tissue environment through increased expression of integrin and TGF-β pathway genes that influence epithelial cell biology. We identified a molecular pathway where skin Tregs license keratinocytes to promote innate inflammation after skin barrier breach. Using a single-cell discovery approach, we identified preferential expression of the integrin αvβ8 on skin Tregs Upon skin injury, Tregs used this integrin to activate latent TGF-β, which acted directly on epithelial cells to promote CXCL5 production and neutrophil recruitment. Induction of this circuit delayed epidermal regeneration but provided protection from Staphylococcus aureus infection across a compromised barrier. Thus, αvβ8-expressing Tregs in the skin, somewhat paradoxical to their canonical immunosuppressive functions, facilitated inflammation acutely after loss of barrier integrity to promote host defense against infection.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov't
Indexed MeSH termsAnimalsImmunity, InnateInflammationMiceMice, CongenicMice, Inbred C57BLMice, TransgenicSkinT-Lymphocytes, RegulatoryTransforming Growth Factor beta

Summary

Regulatory T cells (T) use multiple mechanisms to attenuate inflammation and prevent autoimmunity.

Why This Matters for Hirudotherapy

This study identified a pathway in which skin-resident regulatory T cells (Tregs) expressing integrin αvβ8 activate latent TGF-β after skin barrier breach, promoting keratinocyte CXCL5 production and neutrophil recruitment. This circuit delayed epidermal regeneration but protected against Staphylococcus aureus infection across a compromised barrier. The work is indirectly relevant to ASH's domain because leech therapy involves deliberate skin barrier breach and wound healing, and TGF-β signaling plays roles in both contexts. However, this study involves no leeches, no leech-derived molecules, and no hirudotherapy; the connection is limited to shared mechanistic themes in skin injury and innate immunity.

Citation

Regulatory T cells promote innate inflammation after skin barrier breach via TGF- activation

Moreau JM et al. · Science immunology, 2021

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.