Objective To explore the change of CD40 of peripheral blood B lymphocytes in patients with chronic hepatitis B(CHB) treated by interferon α(IFN-α),and to provide an index in predicting the curative effect.Methods 30 patients with hepatitis B hospitalized were treated with IFN-α for 6 months and 12 patients of non-IFN-α treatment were controls,CD40 of peripheral blood B lymphocytes and IFN-γ were checked before treatment and in the 6th month of IFN-α treatment by using flow cytometry assay and ELISA respecti...