title: Mesenchymal Stem Cells Derived from Human Bone Marrow Support Hematopoiesis in Vitro.
abstract: Bone marrow mesenchymal stem cells (MSCs) are multipotential progenitors of connective tissues and bone marrow stroma as well, which implies the modulatory function of MSCs in hematopoiesis. To clarify the contributions of MSCs to hematopoiesis, the methods for isolation and expansion of MSCs were established and long-term bone marrow cultures were performed using irradiated MSCs as the feeder layer. The results here showed that CD34(+) cells from cord blood formed hematopoietic foci adherent to the monolayer. Furthermore, colony-forming cells remained in the coculture of 5 weeks, indicating the maintenance of long-term culture-initiating cells (LTC-IC). Flow cytometry analysis showed that about 1% of the hematopoietic cells in the culture were positive for CD34 and around 15% were CD41a-positive. It is clear that MSCs maintain LTC-IC in vitro and promote differentiation of hematopoietic progenitors especially into megakaryocytic lineage. The preliminary results here demonstrate that MSCs residing in the bone marrow might be a crucial cellular component in the hematopoietic microenvironment.
authors.affiliation: Department of Cell Biology, Beijing Institute of Basic Medical Sciences, Beijing 100850, China.
authors.forename: Zikuan
authors.initials: Z
authors.lastname: Guo
authors.forename: Peihsien
authors.initials: P
authors.lastname: Tang
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Liu
authors.forename: Jingqing
authors.initials: J
authors.lastname: Yang
authors.forename: Xiusen
authors.initials: X
authors.lastname: Li
authors.forename: Xiaosan
authors.initials: X
authors.lastname: Chen
authors.forename: Ning
authors.initials: N
authors.lastname: Mao