Immunohistochemical studies on vitronectin in elastic tissue disorders, cutaneous amyloidosis, lichen ruber planus and porphyria.

Vitronectin, identical with serum-spreading factor and S-protein of complement, is a glycoprotein present in both plasma and tissue. It stimulates cell adhesion and spreading and affects the complement and coagulation pathways. Vitronectin immunoreactivity was recently found in conjunction with dermal and renal elastic fibres, in renal amyloid deposits in cases of AL- and AA-amyloidosis, and in sclerotic glomerular lesions. Skin specimens from lesions of patients with selected skin diseases were investigated with an avidin-biotin peroxidase technique using both monoclonal and polyclonal anti-vitronectin antibodies and an alkaline phosphatase anti-alkaline phosphatase technique using monoclonal anti-vitronectin antibodies. Vitronectin immunoreactivity was found in association with the abnormal elastic tissue in solar elastosis and pseudoxanthoma elasticum. It was also found in conjunction with dermal amyloid deposits in primary localized cutaneous amyloidosis and in Civatte bodies in cases of lichen ruber planus. In cases of erythropoietic protoporphyria and porphyria cutanea tarda, hyaline perivascular deposits also demonstrated positive vitronectin immunoreactivity. The presence of vitronectin immunoreactivity not only in normal and degenerated elastic fibres but also in various pathological tissue deposits suggests that vitronectin occurs both in elastic fibres and in different types of abnormal protein deposits.