Regulation of Blood Glucose Using Islets Encapsulated in a Melanin-Modified Immune-Shielding Hydrogel

• DOI: 10.1021/acsami.0c23010
• Publication Date: 2021-03-10T19:31:50Z
• Authors: Ling Huang; Jiajia Xiang; Yukai Cheng; Ling Xiao; Qingqing Wang; Yini Zhang; Tieling Xu; Qianrui Chen; Hongbo Xin; Xiaolei Wang
• Keywords: Blood Glucose; Melanins; 0301 basic medicine; 0303 health sciences; Tissue Scaffolds; Islets of Langerhans Transplantation; Biocompatible Materials; Hydrogels; Cells, Immobilized; Cell Line; Diabetes Mellitus, Experimental; 3. Good health; Mice, Inbred C57BL; Islets of Langerhans; Mice; 03 medical and health sciences; Diabetes Mellitus, Type 1; Insulin Secretion; Human Umbilical Vein Endothelial Cells; Animals; Humans

Islet transplantation is currently a promising treatment for type 1 diabetes mellitus. However, the foreign body reaction and retrieval difficulty often lead to transplantation failure and hinder the clinical application. To address these two challenges, we propose a balanced charged sodium alginate-polyethyleneimine-melanin (SA-PEI-Melanin) threadlike hydrogel with immune shielding and retrievable properties. The attractiveness of this study lies in that the introduction of melanin can stimulate insulin secretion, especially under near-infrared (NIR) irradiation. After demonstrating a good immune-shielding effect, we performed an in vivo transplantation experiment. The results showed that the blood glucose level in the SA-PEI-Melanin group was stably controlled below the diabetic blood glucose criterion, and this blood glucose level could be further adjusted after NIR irradiation. In addition, the evaluation after retrieving the SA-PEI-Melanin hydrogel indicated that the islets still maintained a normal physiological function, further proving its excellent immunological protection. This study provides a new approach for the accurate regulation of blood glucose in patients with type 1 diabetes mellitus and contributes to developing a promising transplant system to reconcile real-time and precise light-defined insulin secretion regulation.