Background: Intensive insulin therapy is the standard therapy for type 1 diabetes, however, hypoglycemia is a critical limiting factor. Allogeneic islet transplantation can effectively prevent severe hypoglycemic events and provide excellent blood glucose control (1). However, donor shortage and necessity of immunosuppression are two major issues to expand allogeneic islet transplantation (2). To overcome the two issues, we performed clinical encapsulated neonatal porcine islet transplantation without immunosuppression for the treatment of type 1 diabetes, and demonstrated the efficacy and safety (3-7). In this study, we follow-up the patients and analyze the patient opinions for encapsulated islet xenotransplantation without immunosuppression 10 years after transplantation.
Methods: Twenty one type 1 diabetic patients received microencapsulated porcine islet xenotransplantation in Argentina were enrolled. Seven patients were enrolled in efficacy and safety study and 14 patients were enrolled in safety studies. Opinions of all 21 patients related to the current and pre-transplant status of diabetes control, blood glucose levels, severe hypoglycemia and hyperglycemia required hospitalization were analyzed. In addition, their opinions related to islet xenotransplantation were assessed.
Results: After transplantation all patients significantly improved HbA1c and 5 out of 7 patients significantly reduced daily insulin dose (Figure).
At the time of this survey, average HbA1c of seven patients were significantly lower compared to pre-transplantation (8.5 ± 0.9 (%) at pre-transplant and 7.4 ± 0.5 (%) at the survey, p<0.05) and average insulin dose were also lower compared to pre-transplantation (0.95 ± 0.32 (IU/kg) at pre-transplant and 0.73 ± 0.27 (IU) at the survey).
Based on patient opinions, the majority of patients improved diabetes control (71%), blood glucose levels (76%), and reduced severe hypoglycemia (86%) and hyperglycemia required hospitalization (76%). No patients deteriorated in all of the categories when compared with pre-transplantation. No patients had cancer, psychological problem and one patient had a serious adverse event. The majority of patients wanted to recommend this treatment to other patients (76%) and receive booster transplantation (85.7%).
Conclusions: The majority of patients had positive opinions related to the encapsulated porcine islet xenotransplantation without immunosuppression 10 years after transplantation.