Multicenter prospective study on multivariant diagnostics of autoimmune bullous dermatoses using the BIOCHIPTM technology

Abstract Background The current standard in the serological diagnosis of autoimmune bullous diseases (AIBD) is a multistep procedure sequentially applying different assays. In contrast, the BIOCHIPTM mosaic technology combines multiple substrates for parallel analysis by indirect immunofluorescence (IF). Methods Sera from 749 consecutive, prospectively recruited, direct IF positive AIBD patients from 13 international study centers were analyzed independently and blinded using (i) a BIOCHIPTM mosaic including primate esophagus, salt-split skin, recombinant BP180 NC16A and gliadin GAF3x as well as HEK293 cells expressing recombinant desmoglein1, desmoglein3, type VII collagen, and BP230 C-terminus and (ii) the conventional multistep approach of the Department of Dermatology, University of Lubeck. Results In 731 of 749 sera (97.6%) specific autoantibodies could be detected using the BIOCHIPTM mosaic, similar to the conventional procedure (725 cases, 96.8%). Cohens κ for both serological approaches ranged from 0.84 to 1.00. In 6.5% of sera, differences between the two approaches occurred and were mainly attributed to autoantigen fragments not present on the BIOCHIPTM mosaic. Limitations Laminin 332 and laminin γ1 are not represented on the BIOCHIPTM mosaic. Conclusions The BIOCHIPTM mosaic is a standardized, time- and serum-saving approach that further facilitates the serological diagnosis of AIBD.