In vitro effect of thymosin- alpha 1 and interferon- alpha on Th1 and Th2 cytokine synthesis in patients with chronic hepatitis C

• Published in: Journal of viral hepatitis 2001-05, Vol.8 (3), p.194-201
• Main Authors: Andreone, P, Cursaro, C, Gramenzi, A, Margotti, M, Ferri, E, Talarico, S, Biselli, M, Felline, F, Tuthill, C, Martins, E, Gasbarrini, G, Bernardi, M
• Format: Article
• Language: English
• Subjects: Hepatitis C virus; thymosin ^a1
• ISSN: 1352-0504
• DOI: 10.1046/j.1365-2893.2001.00285.x

Current evidence suggests that increased expression of Th1-associated cytokines is important for immune-mediated eradication of hepatitis C infection, while an increase in Th2-associated cytokines is associated with persistence of infection. In this study we evaluated the effects of thymosin- alpha 1 (TA1), a naturally occurring thymic peptide, and interferon- alpha (IFN- alpha ) on cytokine production in peripheral blood mononuclear cells from untreated patients with chronic hepatitis C. We examined the effect of incubation with TA1, IFN- alpha , or both, on production of Th1-associated cytokines (IL-2, IFN- gamma ), Th2-associated cytokines (IL-4, IL-10), and synthesis of the antiviral protein 2',5'-oligoadenylate synthetase. TA1 treatment induced a significant increase in production of IL-2 and 2',5'-oligoadenylate synthetase. Smaller increases were also seen after treatment with IFN- alpha , while incubation with TA1 and IFN- alpha together led to an additive or synergistic effect. Incubation with TA1 resulted in a decrease in IL-4 and IL-10, whereas IFN- alpha increased these cytokines. The addition of TA1 to IFN- alpha significantly reversed this IFN- alpha -induced increase. Hence, TA1 treatment could benefit patients with hepatitis C infection by increasing the Th1-type response, fundamental for sustained clearance of hepatitis C; and by decreasing the Th2-type response, associated with persistence of viraemia.