721 SCREENING FOR HEPATOCELLULAR CARCINOMA (HCC) IN HCV-MONOINFECTED PATIENTS: IMPACT ON STAGING, THERAPY, AND SURVIVAL AFTER ADJUSTMENT FOR LEAD-TIME BIAS

S269(2) NS3 (aa1531-1550); (3) NS3 (aa1581-1600); (4) NS4b (aa1771-1790); (5) NS5b (aa2571-1790); (6) NS5b (aa2941-2960).The response (activation, IFN-g and IL-4 production) to a range of HCV proteins was assessed by Flow Cytometry.All data were analyzed by SPSS v.14.0 statistical programme (H of Kruskal-Wallis and U of Mann Whitney).Results: Responses above the mean of the 10 controls for each respective mix were considered positive and compared with the results obtained measuring responses >2 standard deviation above the mean.CD4+ activation by peptide (5) was stronger in partners than in controls (p < 0.028).With the first method, twenty-two partners and three controls were positive (22/3) whereas with the second method only could be considered positive twelve and zero (12/0).We were able to demonstrate a higher CD4+ cell percentage secreting IL-4 and IFN-g (double positive response) in partners than in controls in presence of peptide (1) (p < 0.014; 18/2 and 5/1) and ( 5) (p < 0.031; 21/3 and 9/0).A higher reactivity of CD8+ cells to peptide (1) was equally proved (p < 0.004; 12/1 and 0/1).These immune response signs are stronger in patients than in controls. Conclusions:The majority of the partners of HCV chronically infected patients who remain uninfected have demonstrable HCV-specific T-cell responses, in contrast with controls.We think that these responses represent an immunological footprint of HCV exposure that has not resulted in viraemia or HCV antibody seroconversion.The potential protective role of these responses is of great interest.