Immunological investigations

Anti-C1q in chronic hepatitis C virus genotype IV infection: association with autoimmune rheumatologic manifestations.

PMID 25028787


A growing body of evidence suggests that anti-complement-1q (anti-C1q) antibodies are elevated in a variety of autoimmune disease. Therefore, we investigated their prevalence and clinical significance in plasma of patients with hepatitis C virus (HCV) genotype IV in the presence and absence of autoimmune extra hepatic manifestations in comparison to normal healthy individuals. Plasma Anti-C1q Abs levels were assessed by an Enzyme Linked Immunosorbant Assay in 91 chronic HCV-infected patients (51 with and 40 without autoimmune rheumatic manifestations) and 40 healthy volunteers matched for age and gender. Epidemiological, clinical, immunochemical and virological data were prospectively collected. Positive Anti-C1q antibodies were more frequent among HCV patients with extra-hepatic autoimmune involvement, than those without and healthy control subjects. No significant correlations were found between Anti-C1q levels with either the liver activity or the fibrosis scores. In HCV-patients with autoimmune involvements, plasma Anti-C1q levels were significantly higher in patients with positive cryoglobulin, and in those with lymphoma than in those without. These results were confirmed by multivariate analysis. Further large scale longitudinal studies are required to assess and clarify the significance and the pathogenic role of anti-C1q antibodies among HCV infected patients with positive cryoglobulinaemia and lymphoma.