Regenerative Medicine for Hair Health: From Principles to Practice (Part II).

Regenerative technologies are increasingly being explored to support hair growth and follicular restoration, but most remain experimental and grounded in early-stage biological insights. Developmental biology has revealed key signaling pathways, such as WNT, BMP, and SHH, that regulate hair follicle formation and cycling within the bulge and dermal papilla. Building on these principles, a range of regenerative modalities are being studied, including mesenchymal stem cells (MSCs), platelet-rich plasma (PRP) derivatives, and extracellular vesicles (exosomes) derived from bone marrow, adipose tissue, umbilical cord, and platelets, among other sources. These therapies show potential across scarring, non-scarring, and autoimmune alopecia, yet remain limited by variability in protocols, lack of standardized characterization, and the need for long-term safety and regulatory guidance.. This CME article is intended as an educational overview rather than a therapeutic endorsement. Its primary goal is to define terminology, summarize scientific principles, and highlight current research directions to support clinician and trainee understanding. As regenerative therapies continue to evolve, closing the educational gap will help the dermatology community critically evaluate emerging data and responsibly integrate future advances with appropriate scientific, ethical, and regulatory rigor.