Fig. 4. Progressive pathological changes from epidermal overexpression of lamin A and lamin Adel50 in sections from dorsal skin. (A-G,J-L) Haematoxylin and Eosin staining. (A) Normal structure of the skin in late anagen phase is shown in a section from dorsal skin of FVB/N wild-type mice. (B-G) F1 line VF1-07, tetop-LA^G608G+; K5tTA⁺, 9-week-old mice. Intermediate severe and mild stage evident in the same section (B; left and right, respectively). Intermediate severe stage with severe epidermal hyperplasia, extensive immature hyperparakeratosis, and enlargement and displacement of sebaceous glands (B, enlarged in C,E,F), and mild stage (B,D,G). (H,I) Immunohistochemistry using and antibody to adipophilin show staining of lipid-containing cells of the sebaceous unit in FVB/N wild-type (H) and F1 line VF1-07, tetop-LA^G608G+; K5tTA⁺ (I) 17-week-old mice. (J) End-stage disease characterized by epidermal hypoplasia, resting hair follicle, associated hypoplastic sebaceous gland, absence of hypodermis and a well-developed fibrosis of the dermis. (K) F1 line VF1-07 tetop-LA^G608G+; K5tTA^– at 11 months (for comparison with J). (L) Bi-transgenic animals from the SF1-04 line show a well-defined structure of the skin, as shown in a dorsal skin section from a 24.5-week-old mouse. Transgenic mice were supplied with doxycycline until time of weaning – day 21. Scale bars: A,C-G,J-L, 100 µm; B, 500 µm; H,I, 50 µm.