Fms-related tyrosine kinase 3 ligand promotes proliferation of placenta amnion and chorion mesenchymal stem cells in vitro

Placental mesenchymal stem cells (PMSCs) have important biological properties and the potential for application in numerous clinical fields, including hematopoietic stem cell transplantation and myocardial repair. There are two types of MSCs in the placenta, amniotic mesenchymal stem cells (AMSCs) and chorion mesenchymal stem cells (CMSCs). By comparing the biological characteristics of human placental AMSCs with CMSCs, the present study identified that CD90‑ and CD166‑positive cells were located in the amniotic stroma and chorion stroma surrounding the vessels. In addition, the cultured AMSCs and CMSCs expressed high levels of CD73, CD90, CD105, CD29 and CD44; however they did not express CD14, CD34, CD45 and HLA-DR. Furthermore, the amplification of the fms-related tyrosine kinase 3 ligand (FL) in AMSCs and CMSCs was investigated in vitro. The results demonstrated that FL is able to promote the proliferation of AMSCs and CMSCs effectively in vitro, particularly that of CMSCs. In the FL group, the phenotype and the ability of AMSCs and CMSCs to differentiate into mesenchymal lineages did not change. FLT3, the receptor of FL, is expressed in AMSCs and CMSCs. In conclusion, mesenchymal stem cells with low immunogenicity were identified in the placental amniotic membrane and around the chorion axis. Furthermore, FL has a positive effect on the proliferation of AMSCs and CMSCs in vitro; however, does not affect their differentiation potential. It is particularly promising that FL is able to stimulate CMSCs to proliferate in vitro.