Human umbilical cord mesenchymal stem cells under atomic force microscope: Correlation between biological characteristics and ultrastructure / 中国组织工程研究

ABSTRACT

BACKGROUND: The relationship between cellular morphosis and function is undetachable, but there is little investigation about ultrastructure of human umbilical cord mesenchymal stem cells (hUCMSCs).OBJECTIVE: To study the relationship between the functions of hUCMSCs and their ultrastructure obtained by atomic force microscope (AFM). METHODS: hUCMSCs were isolated, cultured, expanded after enzyme digestion. P3 cells were observed under AFM. Immunophenotype and cell cycle were analyzed by flow cytometry, as well as induction of the adipogenic, osteogenic differentiation of hUCMSCs were identified using Oil red O staining and alkaline phosphatase staining. RESULTS AND CONCLUSION: hUCMSCs at passage 3 were strongly positive for CD44 and CD29, weakly positive for CD106, but negative for hematopoietic marker CD34. Cells in G_0/G_1 phase accounted for 80%. Proliferation index was 19.9%. Following adipogenic induction, alkaline phosphatase staining demonstrated brown cytoplasm in cube and polygonal cells. AFM showed hUCMSCs were spindle shape, obvious cytoskeletal filament that connected into nets, which fit for the strong capacities for proliferation, migration and differentiation.