Sentinel biomarkers in HCV positive patients with mixed cryoglobulinemia

Background: Infections, autoimmunity and cancer play a role as determinants of etiology in Hepatitis C virus (HCV) related mixed cryoglobulinemia (MC). Several factors of risk have been suggested as markers of pathogenesis and progression of HCV-related MC into B cell Non-Hodgkin's Lymphoma (B-NHL). Here, we evaluated IgG subclass distribution, free light chains (FLCs) and vascular endothelial growth factor (VEGF) as a new combination of biomarkers. Methods: We measured IgG1-4 subclasses, FLCs and VEGF levels in sera 53 from HCV-related MC, in comparison with 40 sera from HCV negative patients with rheumatoid arthritis (RA) and 30 from healthy blood donors (HBD). Results: IgG3 levels were significantly higher in HCV-MC patients with a decrement of IgG2 and IgG4; FLC levels significantly increased in both MC and RA patients' groups; serological VEGF was higher in HCV-MC patients than in HBD in correlation with k and lambda levels. Conclusion: Our results suggest that a specific IgG subclasses pattern together with raised levels of FLCs and VEGF could represent the biomarker "signature" of an inflammation multistage of acquired immune system.