Figure 2.

Gross appearance and histopathology of tail dermatitis on Blmh null mice. (A) The gross appearance of 18-day-old wild-type (+/+) and Blmh null (−/−) littermates. Dermatitis is apparent only on the tail of Blmh null pups. (B) Tails from adult wild-type (+/+) and Blmh null (−/−) mice. (C–F) Hematoxylin- and eosin-stained cross sections (6 μm) of tail biopsies from Bh+/+ (C) and Bh−/− (D–F) mice. The arrowheads in D and E identify ballooning degeneration (BD) of the stratum spinosum. (F) Full thickness necrosis and abundant neutrophil infiltrate (arrow), from a Blmh null mouse afflicted with severe dermatitis. SB, stratum basale; SC, stratum corneum; SG, stratum granulosum; SS, stratum spinosum; PK, parakeratosis. (Bars = 25 μm.)