Effect of splenectomy alone and in combination with antilymphocyte serum on renal allograft rejection in the rat.

The effect of splenectomy alone and in combination with suboptimal doses of antilymphocyte serum (ALS) have been studied in the relatively weak (DA X Lewis)F1 to DA and the strong DA to Lewis renal allograft models. In the F1 to DA model, splenectomy alone produced a slight but significant prolongation of graft survival and in combination with a suboptimal dose of ALS gave excellent suppression of rejection. In the strong DA to Lewis model, splenectomy alone had no effect on graft survival and there were no additive effects with suboptimal doses of ALS. However, splenectomy alone produced a striking suppression of the lymphocytotoxic response to the kidney grafts in this combination. To elucidate the mechansim whereby splenectomy weakens the immune response, (DA X Lewis)F1 to DNA renal allografts were performed with the renal vein anastomosed to the recipient's portal vein. This procedure had no effect on graft survival.