The three-dimensional nanofiber scaffold culture condition improves viability and function of islets

Significant problems existing in the islet transplantation include a poor survival ability of the islet cells cultured under static conditions in vitro, decreased secretion function, and limited transplantation efficiency. In this study, we cocultured the three-dimensional (3D) self-assembling peptide nanofiber hydrogel scaffold with the islets from adult Wistar rats. The nanofiber scaffold constructed a 3D environment for the islets culture. The results of DTZ staining showed that the purity of the islets in the scaffold was >80%. The result of the fluorescent staining with AO-PI demonstrated that the viability of the islets in the 3D culture environment (within scaffold) was greater than those in the two-dimensional (2D) culture environment (without scaffold). The islets encapsulated in the 3D peptide nanofiber scaffold exhibited better secretion function. The insulin releasing index in the 3D group was remarkably higher than that in the 2D group. By scanning electron microscopy, it was observed that the 3D self-assembling peptide nanofiber hydrogel scaffold formed a nano scale fiber with a geometric form and the islets were encapsulated in this scaffold. Our research demonstrated that this nanofiber scaffold provided a favorable 3D environment for the islets to be cultured in vitro and then improve the secretion function and prolong the survival time of the islet in vitro.