Fig. 3. Transmission electron microscopy of epidermal cysts and expression of markers of hair and epidermal differentiation in cysts. (A-C) Transmission electron microscopy of interfollicular epidermis of wild-type mouse (A) and cysts from transgenic mouse skin (B,C). Arrowheads indicate basement membrane in A and boundary between epithelial cells and dermis in B,C. c, cornified layers. Asterisks in A and C indicate cells with keratohyalin granules. Scale bar: 2 µm. (D-I) Expression of markers of hair and epidermal differentiation in transgenic skin (D,F-I) and wild-type skin (E). Red fluorescence: DAPI staining of cell nuclei. Green fluorescence: hair keratin Ha5 (D,E; note that staining of cornified layer of interfollicular epidermis is nonspecific); keratin 1 (F); filaggrin (G); keratin 6 (H); and laminin (I). IE, interfollicular epidermis; HF, hair follicle. Arrowhead in E indicates matrix cells. Arrowheads in F,G indicate positive staining in cysts. Scale bars: 50 µm in D,F-I; 100 µm in E.
