The Adenosine-Generating Ecto-Enzyme, CD73, Functions as an Intrafollicular Regulator of Human Hair Growth

The study investigated the role of the ecto-enzyme CD73 in human hair growth, particularly its expression in hair follicles (HFs) and its impact on the hair growth cycle. CD73, which synthesizes adenosine from AMP, was found to be strongly expressed in the connective tissue sheath and dermal papilla of HFs, as well as in the inner root sheath epithelium. The use of a CD73-specific antagonist led to inhibited hair shaft production and premature catagen induction in cultured human scalp anagen HFs. However, silencing CD73 expression in the connective tissue sheath did not affect hair growth, suggesting that CD73's role in hair cycle control is linked to its expression in the inner root sheath. The findings indicated that CD73 could be a potential therapeutic target for managing hair growth disorders, with CD73 inhibitors proposed as anti-hirsutism agents.