A study on the fluctuation of HCV antigens during hemodialysis therapy of dialysis patients with the HCV infection using Langmuir's adsorption isotherm

The levels of hepatitis C virus (HCV) are reported to be lower in dialysis patients than those in HCV-positive non-dialysis patients. In order to explain this clinical view, we conducted in-vitro experiments with HCV reperfusion of the different dialysis membranes. In our previous report, curve fitting was performed based on the results, and revealed that adsorption of the HCV antigen on the surface of dialysis membranes can be explained by the mathematical model of Langmuir's adsorption isotherm. Therefore, in order to verify the usefulness of this mathematical model in a clinical study, we investigated the elimination dynamics for HCV antigens levels of pre- and post-dialysis using the same dialysis membrane, which consist of regenerated cellulose membranes (CU; AM-FP1.3),cellulose triacetate membranes (CTA; FB-150E), polymethylmethacrylate membranes (PMMA; BK-1.6P), or polysulfone membranes (PS; F-70S) for the clinical experiment. We predicted the HCV antigen levels of post-dialysis from the HCV antigen levels of pre-dialysis by the mathematical model of the Langmuir's adsorption isotherm. The results showed that HCV antigen levels decreased after dialysis in all cases of dialysis membranes. The coefficients of adsorption rate were 0.651±0.056, 0.654±0.066 with the two cases of the PS membranes, similar results were obtained with the results from the in-vitro experiment, 1.007±0.065 with the CTA membranes, and 1.320±0.1337 with the CU membranes. Correlation coefficient between measured and theoretical values of HCV antigen levels were over 0.97 with the PS, CTA, CU membrane cases. Also the coefficient of adsorption rate of the PMMA membranes was 0.838±0.076. The correlation coefficient between measured and theoretical levels of HCV antigen levels were 0.70 or less, and a result suggested that adsorption and desorption of the HCV antigen in clinical use was repeated. In conclusion, we confirmed the high adsorption of HCV antigen with the PS membrane and the usefulness of Langmuir's adsorption isotherm was suggested in clinical dialysis.