Extended allograft survival of islets grafted into intra-abdominally placed testis

Isolated islets of ACI donor rats were cultured for 4 days at 37 degrees C and then grafted into male diabetic Wistar-Lewis rats into three different organ sites without adjuvant immunosuppression. None of 6 recipients of the intraportal injection of 10 islets per gram of body weight became normoglycemic. Similarly, six rats that received islets injected under the renal capsule remained diabetic. None of six rats that received an intratesticular islet allograft became normoglycemic while these organs remained within the scrotum. By contrast, six rats that were transplanted with an identical number of islets into the testis, which were then surgically placed into the abdominal cavity, promptly became aglycosuric and have remained so for more than 50 days.