Detection of basement membrane zone antigens during epidermal wound healing in pigs.

Bullous pemphigoid (BP) antigen, laminin, and type IV collagen, 3 distinct antigens of basement membrane, were studied by indirect immunofluorescence in the epidermal-dermal junction of re-epithelializing wounds. Partial thickness wounds were made with a dermatome in the skin of white Yorkshire pigs. After 2 or 3 days, the wound site and the surrounding normal skin were excised and cryostat sections were studied using BP sera as well as whole antisera and affinity purified antibodies to laminin and type IV collagen. Laminin and type IV collagen were detected in the basement membrane zone of normal epidermis and at the re-epithelializing epidermal-dermal junction for a variable distance into the healing wound but both were absent from the more distal migrating epidermis. In contrast, BP antigen extended from the basement membrane zone of normal skin throughout the entire epidermal-dermal junction of dermis. These results suggest that in the re-epithelization of superficial wounds laminin and type IV collagen are not present in the initial epidermal-dermal interaction of the migrating epithelium but that BP antigen may be important in this early interaction.