Chitosan hydrogel as an immunoisolative barrier for xenogeneic islet transplantation

Chitosan hydrogel was utilized as an immunoisolative barrier to facilitate the xenogeneic islets transplantation without immunosuppression. Rat islets were encapsulated in chitosan hydrogel and transplanted into the renal subcapsular space of diabetic mice. Non-fasting blood glucose level (NFBG), and body weight were recorded perioperatively. Mice were sacrificed at predetermined intervals and kidney transplanted with islets/chitosan hydrogel was retrieved for histologic examination. Results showed that the NFBG of mice transplanted with islets/chitosan hydrogel maintained in the range of 148-242 mg/dl for four weeks with increased body weight. Histologic sections revealed that the islets successfully engrafted at renal subcapsular space with positive insulin staining. This study indicates that the chitosan hydrogel protects encapsulated islets successfully during xenotransplantation.