Objective\ To understand the effects of serum of patients with rheumatic heart disease and γ interferon on collagen synthesis by valvular fibroblast cultured in vitro, so as to investigate the possible role of transforming growth factor β in genesis of valvular fibrosis and the possibility of γ interferon used to prevent valvular fibrosis in patient with rheumatic heart disease.\ Methods\ Mitral and aortic valve fibroblasts from 5 patients with rheumatic heart disease were cultured in vitro, the cultured ...