Bovine gingival lysate: a novel substrate for rapid diagnosis of autoimmune vesiculo-bullous diseases. A preliminary observation.

Immunoblot assays have been developed to characterize the autoantigens and to detect autoantibodies in muco-cutaneous autoimmune vesiculo-bullous diseases using different substrates. However the results have been inconsistent, because availability and standardization of different substrates has been a major problem. The aim of this study was to develop an immunoblot assay using bovine gingival lysate as substrate because it is easily and readily available as well as inexpensive. Sera from patients with different vesiculo-bullous diseases were studied. These included 25 patients with pemphigus vulgaris (PV), 8 with paraneoplastic pemphigus (PNP), 12 with pemphigus foliaceus (PF), 25 with bullous pemphigoid (BP), and 22 with cicatricial pemphigoid (CP). Serum samples from 40 normal human volunteers were also studied. The autoantibody titers were determined based on the binding pattern of each disease and compared to those obtained by routine indirect immunofluorescence (IIF). Our observations suggest that the titers from immunoblot assays were significantly higher than titers obtained by IIF (P<0.0001). When the autoantibody titers were compared using bovine gingival lysate and human epidermal lysate as substrate, statistically significant differences were not observed. The use of bovine gingival lysate as a substrate will facilitate the rapid and early serological diagnosis of patients with vesiculobullous diseases. It may also be of benefit to laboratory investigators studying these autoantibodies.