Fig. 2.

Discovery and validation of TGM1 autoantibodies in paraneoplastic pemphigus. (A) Explorative screen for TGM1 autoantibodies across multiple autoimmune and idiopathic skin disorders and controls, identifying TGM1 autoantibodies in sera from five patients with paraneoplastic pemphigus. (B) Validation in a replication cohort of 88 patients with paraneoplastic pemphigus and controls. TGM1 autoantibodies were detected in sera from 53 out of 97 (55%) patients with paraneoplastic pemphigus in the discovery and replication cohorts combined. Cutoff = index value 10. (C) The target specificity of serum autoantibodies was studied against a panel of transglutaminases in five subjects with paraneoplastic pemphigus as compared to controls, revealing specific reactivity toward TGM1 in paraneoplastic pemphigus.