Scientists find surprising link between immune system and hair growth

Good news! A ray of hope for all men and women suffering from hair pattern baldness!

"... scientists have uncovered an unexpected molecular target of a common treatment for alopecia, a condition in which a person’s immune system attacks their own hair follicles, causing hair loss. The findings ... describe how immune cells called regulatory T cells interact with skin cells using a hormone as a messenger to generate new hair follicles and hair growth. ..."

From the abstract:

"... Regulatory T cells (Treg cells) are emerging as a critical component of the stem-cell niche for supporting their differentiation. How Treg cells sense dynamic signals in this microenvironment and communicate with stem cells is mostly unknown. In the present study, by using hair follicles (HFs) to study Treg cell–stem cell crosstalk, we show an unrecognized function of the steroid hormone glucocorticoid in instructing skin-resident Treg cells to facilitate HF stem-cell (HFSC) activation and HF regeneration. Ablation of the glucocorticoid receptor (GR) in Treg cells blocks hair regeneration without affecting immune homeostasis. Mechanistically, GR and Foxp3 cooperate in Treg cells to induce transforming growth factor β3 (TGF-β3), which activates Smad2/3 in HFSCs and facilitates HFSC proliferation. The present study identifies crosstalk between Treg cells and HFSCs mediated by the GR–TGF-β3 axis, highlighting a possible means of manipulating Treg cells to support tissue regeneration."

Hair-raising research: Salk scientists find surprising link between immune system, hair growth - Salk Institute for Biological Studies Study highlights how current treatments for alopecia work on a cellular level

Glucocorticoid signaling and regulatory T cells cooperate to maintain the hair-follicle stem-cell niche (no public access)