EFFECT OF A NEW IMMUNOSUPPRESSIVE AGENT, FTY720, ON SURVIVAL OF ISLETALLOGRAFTS

A newly developed immunosuppressant, FTY720, has a unique mechanism th at is quite different from those of conventional immunosuppressants, a nd is presumed to be mediated through decreases in the number of perip heral lymphocytes, especially helper T cells. This study was performed to ascertain whether this innovative drug could prolong islet allogra ft survival. The donors were inbred Lewis rats and the recipients were ACI rats rendered hyperglycemic with intravenous streptozotocin. In t he study group, FTY720 dissolved in distilled water was orally adminis tered at a dose of 5 mg/kg to the recipient ACI rats 1 day before and on the day of grafting. In the control group, only distilled water was orally administered to the recipient ACI rats on the day before and t he day of grafting. Two thousand islets were transplanted into the por tal vein of the recipient rats in the study and control groups immedia tely after isolation. The graft survival time in the study group was s ignificantly longer than that in the control group, indicating that FT Y720 retains a potent effect on the prolongation of islet allograft su rvival. FTY720 could become a useful immunosuppressant for future clin ical islet allotransplantation. (C) 1998 Elsevier Science Inc.