Tight Junction Barriers in Human Hair Follicles – Role of Claudin-1
August 2018
in “
Scientific reports
”
Studysummary This study demonstrated that tight junction barriers exist in human hair follicles but are less tight in hair follicle keratinocytes than in interfollicular keratinocytes, highlighting claudin-1's key role in follicle barrier function and growth. Our plain-language summary of this paper — not a Tressless recommendation.
The study investigated the tight junction (TJ) barrier function in human hair follicles (HFs) and found that a continuous TJ barrier exists from the infundibulum to the lower central part of anagen HFs, as well as surrounding the club in catagen and telogen HFs. This barrier is less tight in HF keratinocytes compared to interfollicular keratinocytes in cell culture experiments. The knock-down of claudin-1, a TJ protein less expressed in HFs of atopic dermatitis patients, led to impaired barrier function, reduced proliferation, and increased apoptosis in hair keratinocytes. These findings suggest that claudin-1 plays a crucial role in HF barrier function and hair growth, as evidenced by the hair growth phenotype in claudin-1 deficient patients and mice.
