Immunofluorescent localization of type IV collagen and laminin in human skin and its application in junctional zone pathology

Abstract

Purified antibodies against type IV collagen and laminin were used ot localize basement membranes by indirect immunofluorescence in various anatomical regions of normal and diseased human skin. The two proteins showed extensive codistribution. A continuous linear staining was found along the epidermal-dermal junction and around hair follicles, sebaceous gland acini and small capillaries. The same proteins also surrounded individual cells such as those found in vessels, hair erector muscles and subcutaneous tissue. Blister formation in bullous pemphigoi left type IV collagen and laminin on the floor of the blister, while the bullous pemphigoid antigen as detected by human autoantibodies was found on both sides of the blister. In solid basal cell carcinoma a strong staining was found around all tumour islands as well as focally within the cell clusters. This suggests that the tumour cells produce these basement membrane proteins but have lost, at least in part, control of polar deposition.

Collagen IV in normal skin and in pathological processes

“…EBA is characterized by the production of autoantibodies against collagen VII in the sublamina densa anchoring fibrils. [21] The authors have described the usefulness of collagen IV immunostaining on paraffin-embedded skin biopsies as an aid for diagnosing EBA in dogs, but it is also useful in humans. [21] In EBA, collagen IV (which forms the fibrous two-dimensional network of the lamina densa), is detected more commonly above the subepidermal blisters than below them.…”

“…[21] The authors have described the usefulness of collagen IV immunostaining on paraffin-embedded skin biopsies as an aid for diagnosing EBA in dogs, but it is also useful in humans. [21] In EBA, collagen IV (which forms the fibrous two-dimensional network of the lamina densa), is detected more commonly above the subepidermal blisters than below them. Collagen IV immunostaining thus offers an inexpensive means to assist in making a diagnosis of EBA distinct from the serological determination of the targeted autoantigen.…”

“…Collagen IV immunostaining thus offers an inexpensive means to assist in making a diagnosis of EBA distinct from the serological determination of the targeted autoantigen. [21]…”

Fibronectin and laminin in Achilles tendon

“…weight 900,000) possessing functionally distinct areas, which interact with other basement membrane components and cell surfaces (Timpl et al 1983). Immunohistochemical and immuno-electron microscopic studies We report the irnmunohistochemical location of fibronectin and laminin in different regions of normal human Achilles tendon and in pathologic conditions, such as tendon rupture, tendinitis, and intratendineal ganglia.…”

Lectin-binding abnormalities in the stromal and epithelial components of basal cell carcinoma

“…Globular deposits of BSAI-positive material are also present within the tumour nests (Figure la). A similar distribution of BMZ components within tumour nodules has been shown for laminin, fibronectin, type IV collagen and bullous pemphigoid antigen, all of which are associated with saccharide moieties (Weber et al, 1982;Nelson et al, 1983;Van Cauwenberge et al, 1983;Grimwood et al, 1984). BSAI is known to bind-to laminin (Shibata et al, 1982) which is produced by the epithelial cells (Stanley et al, 1982b).…”