Further Immunocytochemical Characterization of Cultured Hair Apparatus Cells

The study investigated cultured hair apparatus cells using anti-hair keratin monoclonal antibodies and electron microscopy. Initially, on day 1, a significant portion of cells stained positively with various antibodies, indicating differentiation. By day 3, most cells showed no antibody reaction, suggesting a predominance of immature cells. By day 6, the majority of cells again stained positively, indicating a resurgence of differentiation, which was maintained until day 13. Electron microscopy supported these findings, showing a cycle of initial differentiation, followed by a phase of immaturity, and then a return to differentiation. The study concluded that immature cells in the culture system proliferated and differentiated into various hair apparatus cell types, including outer root sheath cells.