RESUMEN
This study was aimed to investigate the change of cell phenotype and the expression of hematopoiesis associated cytokines in umbilical cord mesenchymal stem cells (UC-MSC) in three-dimensional (3-D) system. MSC were isolated from umbilical cord, and then cultured in 2-D and 3-D system respectively. The phenotype of MSC was detected by flow cytometry; the angiogenic capability of MSC cultured in 2-D and 3-D syitem was assessed using in vitro capillary formation assay. The cytokine expression of MSC in two kinds of culture conditions was measured by real-time PCR. The results showed that MSC were successfully isolated from umbilical cord. Flow cytometry showed that the percentage of CD31, CD133 and CD271 expressed in endothelial cells, endothelial progenitor cells and primitive mesenchymal stem cells increased significantly in 3-D culture conditions, as compared to 2-D system. Capillary formation assay showed that the angiogenic capability of UC-MSC was greatly enhanced. Quantitative PCR showed that the expression of β-actin was upregulated in 3-D system. The expression of some cytokines associated with hematopoiesis, such as G-CSF, LIF, SCF, IL-1α, IL-1β, IL-3, IL-7 and IL-11, increased, especially for LIF, IL-3, IL-7. The expression of IL-10 associated with immune regulation also increased. The expression of SDF-1, IL-6 slightly decreased, but without significant difference. It is concluded that expression of CD31, CD133 and CD271 increases in 3-D system, the angiogenic capability of UC-MSC enhances and the expression of hematopoiesis-associated cytokines in UC-MSC increases in 3-D system.