Specificity of antinuclear antibodies in primary biliary cirrhosis.

OBJECTIVE--To study the specific autoantibodies against nuclear antigens in patients with primary biliary cirrhosis (PBC). METHODS--Sera from 21 patients with PBC were tested for antinuclear antibody (ANA) by indirect immunofluorescence on human epithelial (HEp)-2 cells, and for antibodies to various nuclear antigens by enzyme linked immunosorbent assay (ELISA) using different purified proteins or recombinant proteins as antigens. RESULTS--ANA detected in 10 of 21 patients (48%) with PBC included five anti-centromere antibody (ACA), two speckled, two homogeneous and one nuclear dot staining. ACA were present in 24% of PBC patients. By ELISA, anti-histone antibodies were detected in 81% of PBC patients, anti-ssDNA antibodies in 71% and anti-dsDNA in 10%, anti-topoisomerase-1 antibodies in 24%, anti-Sm/RNP antibodies in 24%, anti-La-48(SS-A) antibodies in 21%, and anti-Ro-60(SS-A) and anti-Ro-52(SS-A) antibodies in 30% and 25%, respectively. CONCLUSIONS--The high frequencies of various antibodies directed against intracellular proteins and nucleic acids in patients with PBC suggests that PBC is a multisystem autoimmune disease which is similar to other systemic autoimmune diseases.