Cytochemistry of Trichohyalin Granules: A Possible Role in Cornification of Inner Root Sheath Cells in Hair Follicles

The study investigated the role of trichohyalin granules (TGs) in the cornification of inner root sheath (IRS) cells in hair follicles using ultracytochemical methods. It was found that TGs undergo structural changes during IRS cell differentiation, transitioning from electron-dense amorphous material (EDM) to filamentous material intertwined with keratin filaments (KFs). The study suggested that TGs contain at least two types of basic proteins: one soluble in low ionic strength salt solution (G-LISS) and another insoluble filamentous protein. These proteins may integrate into KFs as IRS cells cornify, contributing to the thickening of KFs observed in cornified cells.