Prevalence and Clinical Significance of Autoantibodies to Sulphite Oxidase and Glycogen Phosphorylase in Chinese Primary Biliary Cholangitis Patients

Objective To evaluate the prevalence and clinical significance of autoantibodies to mitochondrial sulphite oxidase (SUOX) and glycogen phosphorylase (PYGL) in Chinese PBC patients. METHODS Enzyme-linked immunosorbent assays (ELISA) were developed with purified SUOX and PYGL proteins. Serum samples from 780 PBC patients and 352 healthy controls were used for antibody detection. Statistical analysis was performed with antibody results and biochemical data from PBC patients. RESULTS Antibodies to SUOX and PYGL were found in 14.23% and 22.94% of PBC patients, but also in 6.53% and 9.37% of healthy controls. There is a significant positive correlation between anti-SUOX and -PYGL with anti-M2, -sp100 and -gp210. Anti-SUOX and -PYGL positivity does not correlate with ursodeoxycholic acid (UDCA) response. Time course analysis found no specific change of anti-SUOX or -PYGL antibody titers in positive patients before and after UDCA treatment. CONCLUSIONS The data concluded that anti-SUOX and -PYGL autoantibodies are not serological markers in PBC diagnosis due to a lack of sensitivity and specificity. With the existence of PBC specific autoantibodies in PBC diagnosis and treatment, anti-SUOX and -PYGL status in PBC patients have no significant value.