Preliminary Study Of Induction And Differentiation Of Bone Marrow Mesenchymal Stem Cells Into Islet-Like Structure In Vitro

Objective:To explore the method of inducing BM-MSCs differentiation into islet-like structure. To explore the feasibility of inducing BM-MSCs stem cells into islet-like structure, and preliminarily established the relevant laboratory technology and methods.Method:Adopting the method of natural sedimentation to separate BM-MSCs from bone mallow, then cultivate cells with the method of differential adherent culture. The secondary generation BM-MSCs was separated into two induction groups:nicotinamide group and pancreatic tissue lysate group. With two months of the procedure of induction, Observation and comparation the morphological changes between the two groups. DTZ staining was used to preliminarily identify the pancreatic islet-like cell clusters. The expression of insulin gene was determined by RT-PCR. Immunohistochemistry staining was used to detect whether insulin-positive cells were existed in the islet-like structure. And Mallory staining was used to identify the kinds of pancreatic islet-like cell clusters.Rusult:We obtained the same feather of mesenchymal stem cells with single large nuclear and refraction shining brilliantly. After the procedure of induction, in the nicotinamide group, after induction of lOdays, the stem cells began to gather. After 19 days induction, the number of cell aggregation was increased, the stem cell formed cell clusters. And the cell clusters were not packaged of capsule. In the centre of cell cluster DTZ staining was brown red, the result of RT-PCR determined the expression of insulin mRNA of induced stem cells, and Mallory staining was faint yellow. While in the pancreatic tissue lysate group, after 31 days induction, the induced stem cells formed cell clusters, after 47days induction, the cell clusters were packed with capsule. The formed cell clusters DTZ staining was in dying, most part of the islet-like structure was in brown red, a small part was in scarlet. The result of RT-PCR determined the expression of insulin mRNA of induced stem cells. With immunohistochemistry staining, the islet-like clusters was in brown. While after Mallory staining, the structures are dressed into two different colour, in the centre of the structures are red, periphery of the structures are faint yellow.Conclusion:The BM-MSCs could differentiate into islet-like structures under appropriate condition in vitro. The pancreatic tissue lysate imitated the microenvironment of pancreas, bone marrow mesenchymal stem cells were induced differentiation into islet-like structures, which contained α-like cell in the center of the structure and β-like cell surrounding of the structures, with complete capsule.