This article describes clinical, serologic, and histopathologic features of the first North American cohort of patients with positive anti-p200 serology identified at Mayo Clinic, Rochester, Minnesota, USA and Beutner Laboratories, Buffalo, New York, USA. Forty-seven patients were identified with positive p200 laminin beta 4 autoantibodies, detected with either immunoglobulin (Ig)G or IgG4 modified indirect immunofluorescence on HEK293 cells transfected with recombinant laminin beta.
Enhanced detection of dermal-binding autoantibodies in pemphigoid diseases with a modified indirect immunofluorescence cell-based mosaic assay using IgG4 and optimized testing conditions: a single-centre retrospective study
British Journal of Dermatology | January 9, 2026 | Volume: 195 | Issue: 1 | Pages: 187-188
Patzelt et al. previously characterized dermal-binding autoantibodies using an indirect immunofluorescence (IIF) mosaic assay with cells transfected with p200-laminin β4, laminin-332 or collagen VII subunits among specimens showing a dermal pattern on IIF using salt-split skin (IIF-SSS) and IgG. This study expanded testing to include specimens with either a dermal or mixed pattern on IIF-SSS and demonstrated improved test sensitivity with modified testing methods.