Expression of selected keratin and desmosomes proteins in normal and affected Chesapeake Bay retriever dogs.

<p>Panels A–D: normal age- and breed-matched control dog footpad E–H: affected dog footpad. Panels A, E: keratin K14 was expressed in the cytoplasm of basal keratinocytes of both affected and normal dogs, but the staining pattern was more heterogeneous in affected dogs; some mid-epidermal keratinocytes expressed K14 in affected but not normal dogs. Panels B, F: in normal dogs, keratin K10 was seen with an homogeneous staining in suprabasal keratinocytes (B); in affected dogs, the staining intensity was heterogeneous within and between keratinocytes. Panels C, G: desmoplakin (DSP) staining revealed a typical fishnet intercellular pattern in normal dog skin (C), while it was cytoplasmic and heterogeneous in affected dogs (G). Panels D, H: Using the monoclonal antibody specific for armadillo-repeats of plakophilin-1 (PKP1), this molecule was detected intercellularly, with a dotted pattern, in the superficial epidermis of the normal control CBR (D); this pattern was not seen in samples from affected dogs (H). All panels were shot at ×20 magnification.