Progenitor Cells Expressing Nestin, a Neural Crest Stem Cell Marker, Differentiate Into Outer Root Sheath Keratinocytes

The study investigated the differentiation potential of nestin-expressing progenitor cells in hair follicles using a double-transgenic mouse model. It was found that EGFP+ cells, indicative of nestin expression, were present in the outer epithelial layers of anagen and telogen hair follicles and coexpressed keratin 14, a marker for outer root sheath (ORS) keratinocytes. These cells did not express markers for inner root sheath keratinocytes, suggesting that they are distinct progenitor cells committed to the ORS lineage. The findings highlighted the unique differentiation pathway of these progenitor cells, which could have implications for regenerative medicine and the classification of hair follicle tumors.