Clinical immunology
Importance of NK cells in predicting the effect of IFN-α (Roferon A) and thymus factor X (TFX) therapy in patients with chronic hepatitis C

Introduction: In this study, percentage value and absolute number of NK cell were assessed in patients with chronic hepatitis C (CHC) before and after 3 and 6 months of treatment with interferon (IFN-α) and thymus factor X (TFX). We tried to find importance of NK cells to predict the therapy results. Moreover we evaluated the effect of the therapy on function and morphology of the liver.
Material and Methods: The study included 36 patients with CHC aged between 21-63 years (mean age 41. 36±10.25). Combined therapy with IFN-α 2a and a TFX was applied. Evaluation of percentage value and absolute number of NK cells was performed on peripheral blood cells using standard techniques for whole blood immunofluorescence labeling before therapy in 3rd and in 6th month of therapy. The patients were divided into two groups: group 1 patients with sustained viral response (SVR) (negative HCV-RNA in the serum 6 months after the end of the therapy), group 2 patients without SVR. Changes in NK cells were compared before and during the treatment in relation to viral response. To evaluate influence of the therapy on function and morphology of the liver we compared the results of liver biopsy and plasma clearance with 99m Tc- HEPIDA before and 12 months after the therapy. The results were analyzed statistically.
Results: SVR (absence of HCV-RNA 6 months after therapy – group 1) was gained in 10 from 36 (27.8%) patients. In the liver biopsy (one year after the end of therapy), statistically significant (p<0.05) decrease of necrotic and inflammatory changes intensity was found in the group 1. In group 1 percentage values of NK cells in 24th week were statistically higher in comparison with the values before the therapy (p<0.05). In 24th week of the therapy the statistically significant higher percentage value and absolute number (p<0.05) of the NK cells in group 1 in comparison with the values in group 2 (patients with no SVR) were found.
Conclusions: The obtained permanent viral response (in 27.8% patients) improved liver function and caused decrease of histopathological changes. Statistically significant increase in the percentage of NK cells in patients with SVR, after 24 weeks of IFN-α 2a and TFX compared with the result before the therapy was observed. The percentage and absolute number of NK cells were statistically higher in patients with permanent viral response, which is our contribution and may help to predict the course of the therapy.