Single Step Multivariant Analysis of Serum Autoantibodies in Autoimmune Blistering Diseases Using BIOCHIP® Mosaic Technology

Abstract

A variety of immunoassays for the serological diagnosis of autoimmune bullous diseases has become available within the last decade and, subsequently, greatly facilitated the diagnosis of these disorders. However, a multistep diagnostic procedure is required for optimal diagnosis. Recently, by the use of the BIOCHIP™ technology, s single step assay has been developed that allows the simultaneous testing of different antigens and tissue substrates in a single incubation field. The novel assay is based on an indirect immunofluorescence microscopy employing a BIOCHIP™ mosaic that includes monkey esophagus, primate salt-split skin, antigen dots of tetrameric BP180-NC16A as well as desmoglein 1-, desmoglein 3-, and BP230gC-expressing human HEK293 cells. This BIOCHIP ™ mosaic revealed sensitivities comparable with those of the corresponding ELISA systems and specificities ranged from 98.2% to 100% for all substrates. In a prospective study comparing the BIOCHIP™ mosaic to the standard multistep procedure, a high agreement was found for the diagnosis of bullous pemphigoid, pemphigus vulgaris, and pemphigus foliaceus as well as with sera without serum autoantibodies (Cohen’s κ between 0.88 and 0.97). Here, the use of the novel single-step multivalent assay is exemplified for the diagnosis of bullous pemphigoid and pemphigus vulgaris.