Reduced anchoring fibril formation and collagen VII immunoreactivity in feline dystrophic epidermolysis bullosa

Dystrophic epidermolysis bullosa was diagnosed in a cat with juvenile-onset epithelial sloughing of the oral mucosa footpads, and haired skin. Dermoep idermal separation occurred in the absence of inflammation or cytolysis of basal epidermal cells. Collagen IV-specific immunostaining corroborated the fact that clefting took place below the epidermal basement membrane. Ultra structural examination revealed that the proband's anchoring fibrils exhibi ted a filamentous morphology and were decreased in number compared with tho se in a normal cat. Finally, the attenuated immunoreactivity for collagen V II in our patient led us to suspect. that its encoding gene, COL7Al, could be mutated in this case of feline dystrophic epidermolysis bullosa.