BACKGROUND: Epidermolysis bullosa acquisita (EBA) is a severe autoimmune subepidermal blistering disease characterized by autoantibodies against the N-terminal collagenous domain (NC1) of type VII collagen (Col VII). OBJECTIVE: Development of reliable assays for the detection of anti-Col VII-NC1 antibodies. METHODS: NC1 was expressed in human HEK293 cells and used as target antigen in an enzyme-linked immunosorbent assay (ELISA) and in an immunofluorescence assay (IFA). These two assays were probed in a large cohort of patients with EBA (n = 73), bullous pemphigoid (BP, n = 72), anti-p200 pemphigoid (n = 24), anti-laminin 332 mucous membrane pemphigoid (MMP, n = 15), pemphigus vulgaris (PV, n = 24), and healthy control subjects (n = 254). RESULTS: The cut-off for the ELISA was optimized for accuracy by receiver-operating characteristics (area under the curve [AUC] = 0.9952). IgG reactivity against NC1 was detected in 69 of 73 EBA (94.5%) and 5 control sera (2 healthy controls and 3 BP patients), resulting in a specificity of 98.7%. The IFA showed a sensitivity of 91.8% and specificity of 99.8%. Reproducibility of the ELISA was demonstrated by an intra-class correlation coefficient of 0.97. IgG subclass analyses by ELISA revealed IgG1, IgG2, IgG3, and IgG4 anti-NC1 reactivity in 83.6%, 85.3%, 37.7%, and 83.6% of EBA sera, respectively. LIMITATIONS: The novel assays were not evaluated prospectively and their use in monitoring serum levels during the disease course was not tested. CONCLUSION: The two assays are highly specific and sensitive to diagnose EBA. Their diagnostic competence was demonstrated in a large cohort of well-characterized EBA sera.
BACKGROUND:Epidermolysis bullosa acquisita (EBA) is a severe autoimmune subepidermal blistering disease characterized by autoantibodies against the N-terminal collagenous domain (NC1) of type VII collagen (Col VII). OBJECTIVE: Development of reliable assays for the detection of anti-Col VII-NC1 antibodies. METHODS: NC1 was expressed in human HEK293 cells and used as target antigen in an enzyme-linked immunosorbent assay (ELISA) and in an immunofluorescence assay (IFA). These two assays were probed in a large cohort of patients with EBA (n = 73), bullous pemphigoid (BP, n = 72), anti-p200 pemphigoid (n = 24), anti-laminin 332 mucous membrane pemphigoid (MMP, n = 15), pemphigus vulgaris (PV, n = 24), and healthy control subjects (n = 254). RESULTS: The cut-off for the ELISA was optimized for accuracy by receiver-operating characteristics (area under the curve [AUC] = 0.9952). IgG reactivity against NC1 was detected in 69 of 73 EBA (94.5%) and 5 control sera (2 healthy controls and 3 BP patients), resulting in a specificity of 98.7%. The IFA showed a sensitivity of 91.8% and specificity of 99.8%. Reproducibility of the ELISA was demonstrated by an intra-class correlation coefficient of 0.97. IgG subclass analyses by ELISA revealed IgG1, IgG2, IgG3, and IgG4 anti-NC1 reactivity in 83.6%, 85.3%, 37.7%, and 83.6% of EBA sera, respectively. LIMITATIONS: The novel assays were not evaluated prospectively and their use in monitoring serum levels during the disease course was not tested. CONCLUSION: The two assays are highly specific and sensitive to diagnose EBA. Their diagnostic competence was demonstrated in a large cohort of well-characterized EBA sera.
Authors: Hideyuki Ujiie; David Rosmarin; Michael P Schön; Sonja Ständer; Katharina Boch; Martin Metz; Marcus Maurer; Diamant Thaci; Enno Schmidt; Connor Cole; Kyle T Amber; Dario Didona; Michael Hertl; Andreas Recke; Hanna Graßhoff; Alexander Hackel; Anja Schumann; Gabriela Riemekasten; Katja Bieber; Gant Sprow; Joshua Dan; Detlef Zillikens; Tanya Sezin; Angela M Christiano; Kerstin Wolk; Robert Sabat; Khalaf Kridin; Victoria P Werth; Ralf J Ludwig Journal: Front Med (Lausanne) Date: 2022-06-09
Authors: Nina van Beek; Kristin Rentzsch; Christian Probst; Lars Komorowski; Michael Kasperkiewicz; Kai Fechner; Inga M Bloecker; Detlef Zillikens; Winfried Stöcker; Enno Schmidt Journal: Orphanet J Rare Dis Date: 2012-08-09 Impact factor: 4.123
Authors: Emilia Licarete; Susanne Ganz; Martin J Recknagel; Giovanni Di Zenzo; Takashi Hashimoto; Michael Hertl; Giovanna Zambruno; Gheorghe Hundorfean; Jonas Mudter; Markus F Neurath; Leena Bruckner-Tuderman; Cassian Sitaru Journal: BMC Immunol Date: 2012-04-04 Impact factor: 3.615