Abstract: Objective To investigate the safety and effectiveness of umbilical cord-derived mesenchymal stem cells (MSCs) expanded in serum-free medium for treating chronic hepatitis B patients with decompensated cirrhosis. Methods MSCs were isolated from human umbilical cords, culture-expanded and identified with their morphological, phenotypic and differentiation features. Thirteen chronic hepatitis B patients with decompensated cirrhosis were enrolled in this study. MSCs were intravenously injected weekly at a dose of 5.0 ×107 for 4 continuous weeks. The acute toxicities were observed and the changes of the symptoms and liver function parameters were documented before and after cell therapy. Results The MSCs cultured in the serum-free medium were fibroblast-like in morphology. They were homogenously positive for CD44 and CD73 and negative for CD14, CD31 and CD45. The MSCs could be induced in vitro into osteoblasts and adipoblasts. No acute toxicities including fever, headache and electrocardiographic abnormalities were observed within 24 hours after all injections. Some of the symptoms were relieved and the serum concentration of total bilirubin was significantly decreased after the cell therapy was completed (P<0.05). The mean value of the serum albumin concentration was slightly increased while the values of prothrombin time were not significantly improved. Conclusion The protocol described here, the treatment of chronic hepatitis B patients with decompensated cirrhosis by umbilical cord MSCs cultured in serum-free media, was generally safe and effective in some cases. However, the long-term safety and effectiveness should be further investigated in an increased number of patients.

Key words: Mesenchymal stem cells, Serum-free culture, Cirrhosis