Transplants and Diabetes :: essays research papers

Three Toronto scientists have developed an organ transport procedure that could, among its manybenefits, reverse diabetes. The procedure wasdeveloped by Bernard Leibel, Julio Martin andWalter Zingg at the University of Toronto and theHospital for Sick Children. The story of their workbegan in 1978, when they delved into researchwhich had neer before been tried. They wantedto determine if the success rate of organtransplants would add-on if the receiving system wasinjected with minute amounts of organ tissue priorto the transplant. The intention was to accommodate therecipient to the transplanted tissue and therebyraise the threshold of rejection. In the lineament of thediabetes experiment, this meant injecting rats withpancreatic tissue before transplanting islets ofLangerhans, small clusters of cells scattered passim the pancreas which produce insulin,glucagon, and somatostatin. In their firstexperiment, outbred Wistar rats were injectedwith increasing amounts of minced pancrea s from misrelated conferrer rats for one year while a controlgroup was left field untreated. Then both the treatedand control groups received injections ofapproximately 500-800 islets of Langerhans fromunrelated donors. Of the five treated animals, twobecame clinically and biochemically permanentlynormal. half-dozen months later, Martin examined thecured rats and found intact, functioning isletssecreting all of their hormones, including insulin.None of the controls were cured. Encouraged bytheir first results, Leibel, Martin, and Zinggdecided to repeat the experiment with rats withmuch stronger immune barriers (higher levels ofrejection). cardinal rats out of nine were cured. "Weset up a protocol and worked patiently with smallnumbers," says Leibel, "but the results argonindisputable." In addition to reversing diabetes,there are two other benefits to the pre-treatmentprocedure, according to the scientists. The first isthat the pancreas produces all the other hormon esof a normal pancreas, not just insulin. The secondbenefit is that the transplant recipient doesnt haveto take immunosuppressive drugs, which are sotoxic for diabetics. At present, diabetics whoreceive a transplanted pancreas must take such