Dynamic Interactions of Lymphatic Vessels at the Hair Follicle Stem Cell Niche During Hair Regeneration

The study investigated the role of lymphatic vessels (LV) in hair follicle (HF) regeneration using mouse models. It was found that LV distributed to the anterior permanent region of individual HF and interconnected neighboring HF at the HF bulge in a manner dependent on hair follicle stem cells (HFSC). LV formed triads with individual HF and dynamically flowed across the skin. During HFSC activation or induced HF growth, LV transiently expanded, indicating increased tissue drainage capacity. This expansion was linked to specific gene expression related to extracellular matrix and cytoskeletal reorganization. Depletion of LV was shown to block pharmacological induction of HF growth, highlighting their role as components of the HFSC niche and their contribution to HF regeneration.