CB2-63 polymorphism and immune-mediated diseases associated with HCV chronic infection

AimsTo evaluate whether CB2 variants are associated with the presence of immune-mediated disorders (IMDs) in patients with chronic HCV infection.MethodsOne hundred and sixty-eight anti-HCV/HCV-RNA-positive patients were enrolled, 81 with signs of IMDs and 87 without. In the IMDs group, 22 (27.2%) showed ANA positivity (titers ≥1:160), 3 (3.7%) SMA positivity (titers ≥1:160), 24 (29.6%) had cryoglobulinemia, 25 (30.9%) autoimmune thyroiditis, 4 (4.9%) psoriasis, 2 (2.5%) B-cell non-Hodgkin lymphoma and 1 (1.2%) autoimmune hemolytic anemia. All patients were screened for the CNR2 rs35761398 single nucleotide polymorphism using a TaqMan Assay.ResultsCompared with the 87 patients without IMDs, the 81 with IMDs were more frequently females (65% vs. 45%, p = 0.01), but no significant difference was found in the initial demographic, epidemiological, serological, biochemical or virological data. Instead, the prevalence of patients with the CB2-63 RR variant was significantly higher in the IMD than in the non-IMD group (49.4% vs. 24.1%, p = 0.001). A logistic regression analysis including the CB2-63 receptor (RR vs. QR or QQ), age and sex identified the CB2-63 RR as the only independent predictor of IMDs (p = 0.005).ConclusionsThe data suggest a significant, previously unknown, independent association between the CB2-63 RR variant and IMDs in anti-HCV-positive patients.The study was approved by the Ethics Committee of the Azienda Ospedaliera Universitaria of the Second University of Naples (n° 214/2012).