| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4260686 | Transplantation Proceedings | 2008 | 4 Pages |
PurposeA chitosan/gelatin solution with glycerol 2-phosphate disodium salt hydrate in liquid phase at room temperature becomes a hydrogel at 37°C. The material can be used as an injectable cell carrier into the human body for gelation in situ. We hoped that the chitosan/gelatin hydrogel provided extra protection for insulinoma/agarose microspheres during xenogenic transplantation.Materials and MethodsMouse insulinoma was microencapsulated in agarose as microspheres, which were macroencapsulated in chitosan/gelatin hydrogel. Insulin secreting profiles were first demonstrated in vitro. Diabetic rats were injected subcutaneously with insulinoma/agarose microspheres or insulinoma/agarose microspheres suspended in chitosan/gelatin solution. The nonfasting blood glucose concentrations (NFBG) of diabetic rats were measured perioperatively. Rats were humanely killed 1 month postoperatively and the hydrogel was retrieved for histological examination.ResultsThe insulinoma/agarose microspheres continually secreted insulin for 1 month when macroencapsulated in chitosan/gelatin hydrogel in vitro. The NFBG of diabetic rats injected with insulinoma/agarose microspheres decreased to euglycemic status albeit hyperglycemia was restored within 10 days. The NFBG of diabetic rats injected with chitosan/gelatin hydrogel, which contained insulinoma/agarose microspheres, was maintained at less than 200 mg/dL for 25 days. The histological section revealed immune cell infiltration and accumulation within the hydrogel and around the iusulinoma/agarose microspheres that may have contributed to the slowly increasing NFBG after day 25.ConclusionThis study showed that chitosan/gelatin hydrogel can be used as a cell carrier for an injectable bioartificial pancreas; the hydrogel prolonged the function of cells encapsulated in agarose microspheres during xenogenic transplantation.
