Contribution of SDF-1/CXCR4 axis on proliferation of megakaryocyte co-cultured with human umbilical cord blood-derived stromal cells / 中国实验血液学杂志

ABSTRACT

In order to investigate the effect of stromal cell derived factor-1 (SDF-1)/CXCR4 on the proliferation of megakaryocytic line-HEL cells co-cultured with human umbilical cord blood-derived stromal cells (hUCBSCs) and to further elucidate the mechanism of SDF-1/CXCR4-mediated functions, the HEL cells were co-cultured with hUCBSCs or human bone marrow stromal cells (hBMSCs), the suspended HEL was used as control. The concentrations of SDF-1 in supernatant of hUCBSCs and hBMSCs were detected by ELISA assay. The expression of CXCR4 membrane-bound protein of HEL cells was detected by laser confocal scanning microscopy and flow cytometry, and the expression of CXCR4 mRNA was detected by RT-PCR. The result showed that the concentrations of SDF-1 in different groups were the same at the early stage of culturing. But at 6 days after seeding, the concentrations of SDF-1 increased significantly in the hUCBSCs group, even though the passage was done. By means of laser confocal microscopy, the expression of CXCR4 protein and also red dots of fluorescence could be detected in cytoplasm of HEL cells co-cultured with hUCBSCs. However, there was no significant differences of the CXCR4 mRNA level between different groups (p > 0.05). It is concluded that hUCBSCs may play important roles in secreting high level of SDF-1 and regulating megakaryocyte expression of CXCR4.