Objective    In graft rejection

immune reaction mediated by overactivated T lymphocytes plays a key role

which is characterized by high expression of high-affinity IL-2R on overactivated T lymphocytes. Therefore

this feature of activated T cell makes IL-2R an ideal target for drugs to mediate the suppression or killing of activated T cells in graft rejective reaction. We constructed a kind of recombinant immunotoxin hIL-2-Luffin P1 by combining single chain ribosome inactivating protein Luffin-P1 and human IL-2

then applied hIL-2-Luffin P1 to animal transplantation model to observe its effects on graft reject reaction.     Methods    The rats that underwent kidney allotransplantation

Wistar rats as donors and SD rats as recipients

were used to observe the effect of hIL-2-Luffin P1 on the survival of grafts

with HBSS solvent-treated rats and Luffin P1-treated rats as controls. The pathological changes of grafts in all rats after treatment were observed.     Results    The survival time of the hIL-2-Luffin P1-treated rats was longer than the HBSS-treated rats (P0.01). In the rats treated with HBSS solvent

the renal structure was destroyed and lymphocyte infiltration was obvious. However

the pathological changes of grafts from the rats treated with hIL-2-Luffin P1 were relatively lighter.     Conclusion    In rat kidney allotransplantation

hIL-2-Luffin P1 prolongs the survival time of the grafts

indicating that hIL-2-Luffin P1 can inhibit immunological rejection.