A Novel Subepidermal Blistering Disease with Autoantibodies to a 200–kDa antigen of the Basement Membrane Zone

Abstract

Several components of the basement membrane zone (BMZ) have been identified as antigenic targets in autoimmune bullous diseases. We report a novel disease with autoantibodies to a BMZ antigen that is different from the targets described so far. The patient suffering from this disorder showed tense bullae and severe mucous membrane involvement rapidly responding to oral tetracyclines and colchicine. Histopathologic findings resembled those of dermatitis herpetiformis. Direct immunofluorescence microscopy showed linear deposits of IgG and C3 at the BMZ. By indirect immunofluorescence studies on split human skin, using both 1 M NaCl and suction blistering for dermal-epidermal separation, IgG antibodies localized exclusively to the dermal side of the split. The antibodies were mainly of the IgG4 subclass. By Western blot analysis of epidermal and dermal extracts, the patient's serum unequivocally reacted with a dermal antigen of 200 kDa. It did not recognize bullous pemphigoid antigens, the autoantigen of epidermolysis bullosa acquisita, purified preparations of laminin-1 and laminin-5, or the recently described 105-kDa BMZ antigen. By immunoblotting of concentrated conditioned SCC-25 medium, the patient's antibodies reacted with a band of 200 kDa and several hands of lower molecular weight. No reactivity was seen with extracts of cultured human fibroblasts. By indirect immunogold electron microscopy, immunoreactants localized to the lower lamina lucida. After clearance of skin lesions, both indirect immunofluorescence and Western blot analysis became negative. This patient suffers from a novel autoimmune bullous disease with autoantibodies to a 200-kDa antigen of the BMZ.

Scarring autoimmune bullous disease in a Ugandan patient with autoantibodies to BP180, BP230, and laminin 5

“…In addition, Western blotting of (1) recombinant fulllength (FL-) BP180, (2) keratinocyte extract generated from cultured human keratinocytes, (3) [5][6][7][8] We found both circulating IgG and IgA autoantibodies (serum diluted 1:100 and 1:20, respectively) against FL-BP180 (data not shown), BP180 4575, and BP230-55kD (Fig 3). In addition, IgG autoantibodies targeted BP180 NC16A, LAD-1, and the a3 and g2 chains of laminin 5 (Fig 3).…”

Histopathology of anti-laminin 5 mucous membrane pemphigoid

“…Direct immunofluorescence microscopy of perilesional skin biopsies and indirect immunofluorescence microscopy using NaCl-split normal human skin were performed as described. 10 Immunoblot and immunoprecipitaton studies Patient and control sera were studied for the presence of autoantibodies against laminin 5 by immunoblotting of extracellular matrix of cultured human keratinocytes or immunoprecipitation of radiolabeled human keratinocytes as described previously. 6 The reactivity of patient sera against BP180 (type XVII collagen) was assessed by ELISA with recombinant BP180 NC16A (Medical and Biological Laboratories, Nagoya, Japan) following the manufacturer's instructions and by immunoblotting with CAPSULE SUMMARY d Anti-laminin 5 MMP is characterized by subepidermal blistering and a sparse to moderate superficial lymphohistiocytic infiltrate with neutrophils and/or eosinophils.…”

Klinik und Immunpathologie bei 48 Patienten mit Pemphigus

“…Für die direkte IF wurden Biopsien aus periläsionaler Haut entnommen und als Gefriermaterial verarbeitet [29]. Es wurden 6 µm dicke Kryostatschnitte mit FITC-konjugierten Ziegenantikörpern gegen humanes IgG, IgM, IgA und Komplementfaktor C3 (Beckmann, Mün-chen) inkubiert.…”