Dorsal skin histology.

Female mice, 6 weeks of age, carrying any of the cre-recombinase transgenes but no or only one copy of the conditional Sharpin null gene were normal (A). Normal epidermis was thin with few, if any inflammatory cells in the dermis. However, mice carrying one or two copies of the ubiquitously expressing CMV-cre and homozygous for the conditional Sharpin gene (Sharpin^-/-) (C, D) had lesions identical to the spontaneous Sharpin^cpdm/cpdm mice (B). The epidermis was moderately to severely acanthotic with orthokeratotic hyperkeratosis. Apoptosis (arrows) of keratinocytes was common. Dermis had various degrees of inflammation consisting of a mixture of eosinophils, neutrophils, and macrophages. Lesions were the same for the Krt14 mice (E) but much less severe, although present, in the S100a4 mice (F). Adipoq Sharpin^-/-were normal. Low magnification 100X, high magnification 400X (G).