Prolongation of rabbit -to-dog liver xenograft survival in recpients pretreated with rabbit blood

An attempt was made to prolong rabbit-to-dog liver graft survival by pretreatment of recipients with donor species blood elements. Recipients were given intraarterially whole blood, washed erythrocytes, erythrocyte stroma, leukocytes, and rabbit plasma 1 hr befor transplantation of rabbit liver. Pretreatment with whole blood or red cells was followed by acute depletion of hemagglutinins, hemolysins, complement, and decrease in platelet and leukocyte counts. Rabbit livers transplanted at that time had a 10—20-fold longer survival time. Pretreatment with donor leukocytes only slightly prolonged graft survival, whereas rabbit plasma had no effect at all. It may be concluded that recipient circulating antibodies agglutinating donor erythrocytes are responsible for triggering the process of hyperacute rejection.