Influence of amantadine on CD81 expression on lymphocytes in chronic hepatitis C

Introduction: Interferon alpha (IFN) down regulates CD81 expression on peripheral blood mononuclear cells (PBMC) in patients with chronic hepatitis C virus (HCV) infection. Aim of our study was to investigate whether amantadine alters IFN associated down regulation of CD81 expression on PBMC in patients with chronic hepatitis C. Methods: Nineteen patients with chronic HCV infection received peginterferon alpha-2a/ribavirin (SOC) for 48 weeks. Patients were randomised to 12 weeks amantadine therapy (n = 12) or no additional treatment (n = 7). FACS analysis of CD81 expression on CD4(+), CD8(+), CD19(+), and CD56(+) cells was performed at baseline, week (TW) 4, TVV12, and TW24 of antiviral therapy. Results: A significant decline of CD81 expression was observed on CD4(+), CD8(+), and CD56(+) cells (p = 0.011, p < 0.001, p = 0.015, respectively) but not on CD19(+) cells (p > 0.2). CD81 expression on CD4(+), CD8(+), CD19(+), and CD56(+) cells was not different between patients treated with SOC plus amantadine and patients treated with SOC alone. Conclusion: The current study confirms that CD81 expression is down regulated by SOC on CD4(+), CD8(+) and CD56(+) cells. Amantadine treatment was not associated with CD81 expression. Interaction between amantadine and CD81 is unlikely to be involved in potential antiviral activity of amantadine in chronic HCV infection. (C) 2010 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.