Interferon alpha, gamma, and lambda 2: are they possible culprits in the association between psoriasis and hepatitis C virus?

Abstract

Background High prevalence of hepatitis C virus (HCV) infection among patients with psoriasis has been reported. Interferons (IFNs) play pivotal roles in both the pathogenesis of psoriasis and the immunological response to HCV. Objective To study serum levels of IFN-α, IFN-γ, and IFN-λ2 in psoriatic patients with concomitant HCV infection in comparison with their levels in patients with psoriasis alone and in healthy control. Patients and methods The study included 20 patients with concomitant psoriasis vulgaris and chronic HCV infection, 25 patients with only psoriasis vulgaris, and 24 healthy controls. Serum levels of IFN-α, IFN-γ, and IFN-λ2 were assessed using enzyme-linked immunosorbent assay technique. Results Psoriatic patients with HCV infection showed significantly higher serum IFN-α, IFN-γ, and IFN-λ2 compared with controls (P=0.028, 0.001, and 0.007), higher serum IFN-λ2 levels compared with patients with psoriasis alone, yet significantly lower serum IFN-α and IFN-γ levels in comparison with psoriasis only patients. A significant positive correlation was found between IFN-α and IFN-λ2 levels in psoriatic patients with HCV (r=0.536, P=0.015). Conclusion IFN-α and IFN-γ play important roles in the pathogenesis of psoriasis, yet they are not likely to be the cause of development of psoriasis in chronic HCV-infected patients. High levels of IFN-λ2 among psoriatic patients with HCV infection but not in patients with psoriasis alone point to its possible safety in the treatment of HCV in psoriatic patients.

Keywords

• hepatitis c virus
• interferon-α
• interferon-γ
• interferon-λ2
• psoriasis