Normal Insulin Secretion from Immune-Protected Islets of Langerhans by PEGylation and Encapsulation in the Alginate-Chitosan-PEG.

BACKGROUND

Pancreatic islet transplantation is one of the most promising strategies for treating patients with type I diabetes mellitus.

OBJECTIVE

We aimed to assess the immunoisolation properties of the multilayer encapsulated islets using alginate-chitosan-PEG for immunoprotection and insulin secretion from the encapsulated islets induced under different glucose concentrations .

MATERIALS AND METHODS

In this study, the islets were isolated from Wistar rats. The biological function (insulin secretion) of the immunoisolated islets following to PEGylation and encapsulation in the alginate-chitosan-PEG, separately, in addition to their immuno-protection in a co-culturing with the lymphocytes isolated from the male C57BL/6 mice were investigated, respectively.

RESULTS

Alginate-chitosan-PEG decreased IL-2 secretion from the lymphocytes co-cultured with islets. Also, insulin secretion from the encapsulated and PEGylated groups was stimulated by glucose (i.e., 5.6 and 16.7 mM of glucose, respectively); showed insulin secretion similar to the naked islets, without coating, after 30 and 60 min of incubation.

CONCLUSION

In conclusion, encapsulation and PEGylation have no negative effect on the insulin secretion and glucose sensitivity of the islets for all of the groups. Also, encapsulation decreased IL-2 secretion from the lymphocytes.