[Notch pathway gene expression after co-culture of umbilical cord mesenchymal stem cells and hematopoietic stem cells].

AIM: To detect the gene expression of signal molecules involved in the Notch pathway after co-culture of umbilical cord mesenchymal stem cells (UC-MSCs) and CD34(+); hematopoietic stem cells.

METHODS: UC-MSCs were isolated by collagenase digestion, and the phenotype was tested by flow cytometry. The differentiation ability of UC-MSCs into adipocytes, osteoblasts and chondroblasts was analyzed using three induction systems, respectively. After UC-MSCs were co-cultured in vitro with CD34(+); cells for 6 d, real-time PCR was applied to investigate the gene expressions of notch ligands (Jagged 1, 2 Delta1, 3, 4), receptors (Notch1-4) and Hes-1.

RESULTS: The isolated UC-MSCs were found with the typical characteristics of MSCs in morphology, phenotype and differentiation ability. After co-culture in vitro of MSCs and CD34(+); cells, real-time PCR assay showed a significant up-regulation of Jagged-1 and Notch1. The expression of Hes-1 in CD34(+); cells also increased, but there was no obvious change after DAPT (50 nmol/L) was added in co-culture medium.

CONCLUSION: Notch signaling may play an important role in the process of the expansion of hematopoietic stem cells supported by UC-MSCs.