Concentration of autoantibodies to native 60‐kd ro/ss‐a and denatured 52‐kd ro/ss‐a in eluates from the heart of a child who died with congenital complete heart block

Objective. To determine the serologic specificity of acid eluates from tissues of a child who died with congenital complete heart block (CCHB). Methods. Tissues were extracted, acid eluted, and the IgG and antibody titers determined on the eluates by enzyme-linked immunosorbent assay. Results. Antibodies to native 60-kd and denatured 52-kd Ro/SS-A were found to be enriched only in the heart eluate, and not in the eluates from brain, kidney, and skin. Conclusion. These findings indicate a major role for anti-native 60-kd Ro/SS-A in the immunopathogenesis of CCHB.