Immunofluorescent staining with antibodies to factor VIII, fibronectin, and collagenous basement membrane protein in normal human skin and port wine stains.

Specific antibodies directed against three important components of the vessel wall (collagenous basement membrane protein-type IV collagen, fibronectin, and factor VIII) were used to study and compare the distribution of these proteins in normal skin and port wine stains. Collagenous basement membrane protein was localized to the basement membrane and basal lamina zones of blood vessels, appendages, arrector pili muscles, endoneurium and perineurium, and the dermoepidermal junction of both port wine stains and normal skin. Vessels of the port wine stain as well as those of normal skin showed a similar narrow uniform homogeneous line of fluorescence. Granular endothelial staining was seen in the blood vessels of both normal skin and port wine stains. The distribution of fibronectin was that of a low-intensity punctate pattern situated in the subendothelial region of both port wine stain and normal vessels and in the basement membrane zones of hair follicles, endoneurium and perineurium, and the dermoepidermal junction.