Induction of Hard Keratin Expression in Non-Nail-Matrical Keratinocytes by Nail-Matrical Fibroblasts Through Epithelial-Mesenchymal Interactions

The study investigated whether nail-matrical fibroblasts could induce hard keratin expression in non-nail-matrical keratinocytes through epithelial-mesenchymal interactions. Researchers constructed skin equivalents in three groups: ventral keratinocytes with ventral fibroblasts (group A), ventral keratinocytes with nail-matrical fibroblasts (group B), and nail-matrical keratinocytes with ventral fibroblasts (group C). Immunohistochemical analysis showed that hard keratin was expressed in groups B and C, with continuous distribution in group B and spotty distribution in group C. The findings suggested that nail-matrical fibroblasts could induce hard keratin in non-nail-matrical keratinocytes, indicating potential applications for treating nail injuries and reconstructing lost nails using tissue-engineered grafts.