Isotype analysis of the anti–CENP‐B anticentromere autoantibody: Evidence for restricted clonality

Abstract
Utilizing the centromere B fusion protein (CENP‐B) and specific, matched monoclonal antiisotype reagents in an enzyme‐linked immunosorbent assay, we found that anti–CENP‐B autoantibodies were skewed to the IgG1 isotype. The overall k:λ light chain ratio was 2:1, although several individual sera showed a strong predominance of one of the light chains. Isoelectric focusing of light chain–skewed sera showed polyclonal patterns. Our findings are consistent with the anti–CENP‐B autoantibody response being a chronic, antigen‐driven response.