Expression of Laminin, Type IV Collagen and Fibronectin Molecules Is Related to Embryonal Skin and Epidermal Appendage Morphogenesis.

The study investigated the expression of laminin, type IV collagen, and fibronectin in the basement membranes of fetal human skin, focusing on their role in skin and epidermal appendage morphogenesis. It was found that these proteins began to express in the germinative epithelial cells of the skin at the hair follicle bulbs, with fibronectin appearing at 12 weeks and laminin and collagen type IV at 19 weeks of gestational age. By 20 to 21 weeks, their expression extended to the epithelial epidermal cells and the basement membrane at the dermal-epidermal junction, indicating their involvement in the development of skin structures during gestation.