Abstract: ObjectiveTo observe and compare the efficacy of two types of microencapsulated rat islets xenotransplanted into diabetic mice. MethodsThe mice diabetic model made with injecting 3% Streptozotosin through tail vein. Four groups were assigned: control group, naked islet transplantation group, alginate-BaCl₂ microencapsulated islet transplantation group, agarose-PSSa microencapsulated islet transplantation group.300 islets were transplanted under the renal envelope of each diabetic mice respectively. ResultsThere were no significant difference in mean level of the blood glucose before transplantation among four groups. One week after transplantation, the respective mean level of the blood glucose in four groups were (7.26±1.56) mmol/L in alginate-BaCl₂ microencapsulated islet transplantation group, (7.14±1.04) mmol/L in agarose-PSSa microencapsulated islet transplantation group, (7.42±1.52) mmol/L in naked islet transplantation group and (22.54±1.24) mmol/L in control. There were significant difference between the two encapsulated islet groups and the other two groups. The survived period of the two encapsulated islet transplantation groups were longer than that of the other two groups. The survived period of the alginate-BaCl₂ microencapsulated islet transplantation group was longer than that of the agarose-PSSa microencapsulated islet transplantation group (92 d vs 56 d),the same as the time of keeping nomal blood glucose level (76 d vs 41 d). ConclusionMicroencapsulated rat islets with this two materials can survive in diabetic mice with their biological activity, and the alginate-BaCl₂ microcapsules are better than the agarose-PSSa microcapsules.

Key words: diabetes mellitus, microencapsulation, alginate-BaCl₂, agarose-PSSa, xenotransplantation, islet, rat, mouse