Improvement in the Mechanical Properties of Cell-Laden Hydrogel Microfibers Using Interpenetrating Polymer Networks

Microencapsulation of cells is a promising technique in biomedical applications such as cell therapy. Recently, cell-laden hydrogel microfibers have been proposed as another shape microcapsule instead of microbeads; however, these are brittle with little stretching capability. This paper describes a cell-laden hydrogel microfiber that showed enhanced mechanical properties and handleability by using a double-network (DN) hydrogel consisting of alginate and polyacrylamide. The DN hydrogel microfiber supported approximately 6-fold higher strain and exhibited 10-fold higher tensile strength than the conventional alginate form. The DN hydrogel microfiber could also encapsulate pancreatic β cells while maintaining cell viability and function. The in vivo functionality of the DN hydrogel microfiber was demonstrated by transplanting 3D assemblies of the microfibers into the intraperitoneal or subcutaneous space of diabetic mice, which successfully decreased their blood glucose levels. Thus, cell-laden DN hydrogel microfibers may represent a promising material for various biomedical applications.