In a recent study microarray gene profiling of peripheral blood mononuclear cells from hepatitis C patients treated with Interferon-alpha was performed. 88 genes directly relating to functions of immune cells were up-regulated, including genes involved in antigen processing and presentation, T-cell activation, lymphocyte trafficking, and effector functions, suggesting that Interferon-alpha up-regulates multiple genes involving different aspects of immune responses to enhance immunity against hepatitis C virus (7).