Abstract: The present invention provides a liver preservation solution containing trehalose and dibutyryl-cAMP. The content of nitroglycerin in the preservation solution is preferably lower than 0.44 mM. In the liver preservation solution of the present invention, since the toxicity due to nitroglycerin, which is observed during liver preservation, has been improved, liver transplantation can be performed with a high engrafted rate.

Abstract: The present invention provides a liver preservation solution containing trehalose and dibutyryl-cAMP. The content of nitroglycerin in the preservation solution is preferably lower than 0.44 mM. In the liver preservation solution of the present invention, since the toxicity due to nitroglycerin, which is observed during liver preservation, has been improved, liver transplantation can be performed with a high engrafted rate.

Abstract: The present invention provides a method of producing a regulatory T cell, which includes culturing a peripheral CD25+CD4+ T cell of a naive phenotype to give the regulatory T cell. The CD25+CD4+ T cell can be cultured under stimulation with an antigen. According to the method, a mammalian regulatory T cell can be produced in vitro and an antigen-specific regulatory T cell can also be produced. The regulatory T cell produced by the method is useful as an immunomodulator for the prophylaxis or treatment of rejection reaction in organ transplantation, allergic disease, autoimmune disease, graft-versus-host disease (GVHD), infertility and the like.

Abstract: The present invention provides a screening method for a compound capable of inducing regulatory T cells, comprising the following steps: (1) a step for culturing CD4+ T cells having a naïve phenotype in the presence of a test compound, and isolating T cells from the culture product; (2) a step for evaluating the immunosuppressive function of the T cells isolated in the step (1); (3) a step for obtaining the foregoing test compound as a compound capable of inducing regulatory T cells if the results of the evaluation in the step (2) show that the T cells isolated in the step (1) have immunosuppressive function. The present invention also provides a method of producing regulatory T cells, comprising culturing CD4+ T cells having a naïve phenotype in the presence of a rapamycin compound to obtain regulatory T cells.

Abstract: The present invention provides a liver preservation solution containing trehalose and dibutyryl-cAMP. The content of nitroglycerin in the preservation solution is preferably lower than 0.44 mM. In the liver preservation solution of the present invention, since the toxicity due to nitroglycerin, which is observed during liver preservation, has been improved, liver transplantation can be performed with a high engrafted rate.