Anti-C1q IgG autoantibodies
Pathogenic autoantibody
- Expression
- Elevated (90-100% of patients)
- Evidence level
- established
Role in pathogenesis
IgG autoantibodies that bind the collagen-like region of C1q via their F(ab')2 fragments. Present in 90-100% of HUVS patients. Unlike SLE anti-C1q antibodies, HUVS antibodies can bind reduced/denatured C1q. Drive complement activation and immune complex deposition in vessel walls.