LONG-TERM SURVIVAL OF HETEROTOPIC HEART-TRANSPLANTS IN ALLOGENIC RATSWITHOUT USING ANTI-REJECTION DRUGS AFTER INDUCING IMMUNE TOLERANCE

Graft rejection is a baffling problem in organ transplantation which h as so far no successful resolution. Present antirejection therapy is e xpensive, toxic, susceptible to infection, oncogenesis and atheroscler osis. With the use of 2 extremely histoincompatible strains of rats as model, it was found that when six donor splenocytes preconditioned by an extract from the culture medium of streptomyces caespitosus mere i njected into the host, after 2 weeks immune tolerance heterotopic tran splanted donor hearts could survive normally more than 100 days withou t using any anti-rejection drug. Their mean survival time was 141.4 +/ - 2.56 days, while that in the control group was only 11.7 +/- 3.48 da ys (P < 0.005). Thus, the present research offers some bright prospect s in the area of organ transplantation.