ABSTRACT
BACKGROUND: Mesenchymal stem cells in Wharton's Jelly of the human umbilical cord can induce differentiation into islet-like cells.OBJECTIVE: To verify the possibility of human umbilical cord derived mesenchymal stem cells co-cultured with rat pancreatic cells differentiate into islet-like cells, and to observe the effects of transplantation of islet-like cells on blood glucose of diabetic rats.METHODS: Mesenchymal stem cells in Wharton's Jelly of the human umbilical cord was separated, induced, passaged, and co-cultured with pancreatic cells to induce differentiation into islet-like clusters. Rats were divided into the normal control, model and experimental groups. Rats in the model group were prepared for diabetic models, and those in the experimental group were transplanted islet-like cells after model preparation. RESULTS AND CONCLUSION: There were cells crawled out of cultured Wharton's Jelly of the human umbilical cord, and morphology of adhered cells turned into fusiform shape at 7 days. The isolated cells are characterized by expressing specific surface markers of mesenchymal stem cells, such as CD44, CD29, CD105, but not expressing CD34, CD45 or CD14. The cells were strongly stained by PDX-1 and human insulin at 7 and 10 days. Compared with the simple culture group, the expression of human insulin and concentration of C-peptide were obviously increased; PDX-1 and human insulin mRNA expressions were highly expressed at 7 and 10 days after induction. Compared with the model group, the streptozotocin test of rats in the experimental group was obvious decreased (P < 0.01), but extremely higher than that of the normal control group at 1 week after transplantation (P < 0.01). Brdu positive nuclei and insulin positive kytoplasms could be seen in the experimental group at 8 weeks after transplantation. The results demonstrated that, umbilical cord derived mesenchymal stem cells existed in Wharton's Jelly. The co-cultured cells promote mesenchymal stem cells differentiating into islet-like cells, which can dramatically decrease blood glucose in diabetic rats.