15-Deoxyspergualin: a newly developed immunosuppressive agent and its mechanism of action and clinical effect: a review. Japan Collaborative Transplant Study Group for NKT-01.

15-Deoxyspargualin (DSG) is a synthetic analogue of spergualin isolated from the culture filtrate of Bacillus laterosporus. It shows a strong immunosuppressive effect by antiproliferating action inhibiting the IL-2-stimulated maturation of T cells from the G0/G1 phases to the S and G2/M phases. Hsc70, a constitutive member of Hsp70 was identified as the immunophilin of DSG by Nadlar et al. In allogeneic transplantation of rat heart and dog kidney, DSG was definitely proved to prevent rejection and to rescue ongoing rejection. Our multicenter clinical trials on DSG showed that the percent efficacy to reverse acute rejection was 70-80%, and 600 days graft survival was 90% in the cases effectively treated with DSG at acute rejections. The combined use of DSG with methylprednisolone to treat acute rejection and the use of DSG to treat rejections in chronic phases were reported as the beneficial uses of DSG.