Abstract:

Abstract:Objective To isolate and culture mesenchymal stem cells (MSCs) from human term umbilical cord and placenta， and to study the proliferative and adipogenic capacities of human fetus tissue MSCs (FT-MSCs),umbilical cord MSCs (UC-MSCs) and placenta MSCs (PL-MSCs),and to provide an experimental basis for its clinical use.
Methods The human term umbilical cord and placenta were obtained in sterile condition.The UC-MSCs and PL-MSCs were isolated by digestion using collagenase Ⅰ,the FT-MSCs were provided by Zhongke Bio-engineering Co.,Ltd.The  3th or 4th passages of MSCs were selected in this study.The cell morphology was observed by inverted microscope.The proliferative ability was detected by living cell number counting method.The cell cycle and the positive expression rates of the surface markers of three kinds of MSCs were detected by flow cytometry (FCM).The 3th generation of UC-MSCs,PL-MSCs,and FT-MSCs were induced to differentiate into adipogenic cells.18 d after being induced,the differentiated cells were stained with Oil red O and the positive cells were counted.The adipogenic differentiation abilities of MSCs from the different tissues were assessed.Results The MSCs from different tissues were spindle-shaped adherent cells.The FCM results showed the surface marker of MSCs were positive for CD44,CD73,CD90, and CD105,and negative for CD14,CD34,and CD45.The FT-MSCs displayed higher proliferative  ability than UC-MSCs and PL-MSCs（P<0.01）.The  proliferative index (PI) of FT-MSCs (36.66%±1.30%) was significantly higher than  those of UC-MSCs (18.23%±1.10%) and PL-MSCs (10.03%±1.20%)(P<0.01).The lipid droplets were found after induction,and the results of Oil red O staining were positive in all kinds of MSCs. However the adipogenic capacity of UC-MSCs was significantly higher  than those of PL-MSCs and FT-MSCs(P<0.01).Conclusion UC-MSCs,PL-MSCs and FT-MSCs have similar biological characteristics and cell surface markers.But FT-MSCs have the strongest proliferative ability and activity,UC-MSCs have the strongest adipogenic capacity in vitro.

Key words:  , embryonic tissue, umbilical cord, placenta, mesenchymal stem cell, proliferation, adipogenesis