IgA and IgM autoantibodies against the β-chain of ATP synthase (ASA) have been separately described in different cohort of patients with coeliac disease and nephrotic syndrome. In the later case, they occur in concomitance with anti-actin IgM and/or with anti-nuclear autoantibodies that indicate some parallelism with systemic lupus erythematosus (SLE). ASA IgM were found in children who developed nephrotic syndrome under 15 years and presented resistance or dependence to steroids and cyclosporine. Focal segmental glomerulosclerosis and mesangial proliferation with IgM deposition was the histology background in almost all cases. Patients tested positive for circulating ASA IgM could not be separated from other nephrotic patients on clinical grounds and represent a subset with uncertain significance. Further screening studies will better define clinical implications and inconsistencies and possibly define personalized therapeutic approaches. The only method for ASA detection utilizes indirect western-blot in which extracts of human podocyte cell lines are first separated by two-dimensional electrophoresis and are then incubated with plasma. Formation of an adduct with podocyte proteins is revealed by an anti-human IgM linked with alkaline phosphatase.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)