Ultrastructure and phagocytotic function of human placental mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND:Placental mesenchymal stem cel s with rich sources are similar to bone marrow mesenchymal stem cel s in terms of morphology, surface markers and differentiation potential, which are one of ideal mesenchymal stem cel s in human body. However, there are few studies addressing the ultrastructure and phagocytotic function of human placental mesenchymal stem cel s and its physiological role in the the placenta has been little explored. OBJECTIVE:To investigate the ultrastrcture and phagocytotic function of placental mesenchymal stem cel s. METHODS:Placental mesenchymal stem cel s obtained from five placentae of normal pregnancy were cultured in vitro and observed for ultrastructure under transmission electron microscope. The fluorescent beads were added in the supernatant for 3 hours, and then the phagocytosis of placental mesenchymal stem cel s was evaluated by flow cytometry. RESULTS AND CONCLUSION:Under the transmission electron microscope, placental mesenchymal stem cel s had large nuclei with prominent nucleoli. In the cytoplasm, a plenty of rough endoplasmic reticula was seen, dilated or stacked. The cytoplasm was also rich in Golgi apparatus and lysosomes. The cel surfaces were covered by microvil i. The intercel ular junctions could be seen occasional y. A part of cel s from these five samples could phagocytose fluorescence beads, which ranged from 49.6%to 18.4%. The ultrastructural characteristics of placental mesenchymal stem cel s suggested these cel s were active to synthesize and secrete proteins and had phagocytotic function, indicating placental mesenchymal stem cel s may play a role in keeping the balance of micro-environments and clean the foreign substances in the placenta.