Objective To assess the effects of different immunosuppressive drugs on proliferation and function of regulatory T cells (Tregs). Methods We searched MEDLINE (1966 to November 2009), EMbase (from inception to September 2009), and The Cochrane Library (Issue 4, 2009) for clinical and basic research about the effects of various immunosuppressive drugs on Tregs. Data were extracted and methodological quality was assessed by two independent reviewers. Outcome measures for clinical research included blood Tregs levels, acute rejection episodes, and graft function. Outcome measures for basic research included percentage of Tregs proliferation, function, Tregs phenotype, and evidence for possible mechanisms. We analyzed data qualitatively. Results Forty-two studies, including 19 clinical trials and 23 basic studies, were included. The immunosuppressive drugs studied were calcineurin inhibitors (CNIs), Rapa, anti-metabolism drugs, IL-2 receptor-blocking antibodies, T-cell depleting antibodies, and co-stimulation blockade antibodies. Most of the studies were on Rapa and CNIs. Eight basic studies on Rapa and CNIs showed that Rapa could promote the proliferation and function of Tregs, while CNIs could not. Five clinical trials involving a total of 158 patients showed that patients taking Rapa had higher blood concentration of Tregs than those taking CNIs, but no differences were found in graft function (6-42-month follow-up). Conclusion There is substantial evidence that Rapa favors Tregs survival and function. However, the larger number of the blood Tregs in the patients treated with Rapa does not show any correlation with better graft function. Large-sample and high-quality clinical studies with longer follow-up are needed to thoroughly assess the efficacy of immunosuppressive drugs on Tregs and to reveal whether a relationship exists between Tregs and graft function.
Objective To investigate the effect of ABO-incompatible liver transplantation on patients with acute hepatic failure. Methods A retrospective review was undertaken on the clinical data of 3 cases （1 case of Budd-Chiari syndrome, 1 case of liver cancer and 1 case of severe hepatitis B were included） undergoing ABO-incompatible liver transplantation for acute hepatic failure. The patients were given quadruple immunosuppression after operation. Results Postoperative complications including pulmonary infection, central pontine myelionlysis and acute rejection was suffered from by the patient of Budd-Chiari syndrome who was then given a positive deal and had survived for more than 14 months. The patient of liver cancer was aggravated by severe infection who died of multiple organ failure on day 13 after operation. The patient with severe hepatitis B was made more severe by acute renal failure whose kidney function was restored with continuous renal replacement therapy. Conclusion The outcome of ABO-incompatible liver transplantation can be improved with refined peri-transplant management and better immunosuppressive strategies. ABO-incompatible liver transplantation should be viewed as an important option in patients with acute hepatic failure awaiting an emergency procedure.