Combined FXIII-C3 autoantibodies elicit bleeding and complement dysfunction in autoimmune FXIII deficiency.

ABSTRACT: Autoimmune factor XIII (FXIII) deficiency is a rare hemorrhagic disease characterized by severe bleeding and a high mortality rate. However, the pathogenesis of this disease remains unclear. FXIII consumption caused by infections is becoming increasingly common. Our clinical investigation, combined with in vivo experiments, revealed that patients and mice with autoimmune FXIII deficiency displayed complement dysfunction and that pathogenic infection and autoantibody generation were positively correlated. Further analysis revealed the presence of combined FXIII-C3 autoantibodies in patients with autoimmune FXIII deficiency. These combined autoantibodies neutralize FXIII, cause bleeding, and form a complex with C3, inhibiting complement activation and complement-mediated adaptive immune resp

SUBMITTER: Luo S 

PROVIDER: S-EPMC12867163 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature