Fig. 3

Schematic localization of S100A2, S100A3 and S100A6. A Hair matrix cells (some S100A2 positive) proliferated and differentiated into cortical and cuticular cells (S100A3 positive), and the inner root sheath cells (S100A6 positive). Outer root sheath cells (S100A2 positive) surround the hair bulb. Co, cortex of hair; Cu, cuticle of hair; IRS, inner root sheath; ORS, outer root sheath. B Tumour island of pilomatrixoma. Basophil cells (patellar S100A2 positive) divide into adhesion shadow cells (S100A3 positive), transparent shadow cells (S100A6 positive), and possibly columnar or dispersed cuticle cells (S100A3 positive). The outer root sheath cells are inherited by squamous cells (S100A2 positive). (Adapted from reference 83)