Endothelial cells from human umbilical vein inhibit generation of monocyte-derived dendritic cells / 中国实验血液学杂志

This study was aimed to investigate the effect of human umbilical vein endothelial cells (HUVEC) on dendritic cell (DC) development. First, HUVEC were isolated from human umbilical cord by collagenase digestion, and then the morphology, immunophenotypes and functions were identified. Furthermore, the HUVEC were cocultured with CD14(+) monocytes under the cytokine condition for detecting the influence of HUVEC on differentiation of CD14(+) cells to DC. The phenotype of dendritic cells derived from CD14(+) cells was analyzed by flow cytometry, the immunoregulatory function of DC was tested by mixed lymphocyte reaction (MLR). The change of IL-6 and VEGF as well as EPK and p38 signal pathway were analyzed by neutral antibody experiment and Western blot. The results showed that HUVEC isolated from human umbilical cord were characterized by spindle-shaped morphology, homogenous immunophenotypes (vWF(+)CD31(+)CD73(+)CD45(-)HLA-DR(-)CD86(-)CD34(low)), Dil-Ac-LDL incorporation ability and forming capillary-like structures. Following stimulation with granulocyte-macrophage colony-stimulating factor (GM-CSF) plus interleukin-4 (IL-4), HUVEC cocultures could inhibit the initial differentiation of CD14(+) monocyte to DC. Interestingly, IL-6 and VEGF enhanced the suppression effect of HUVEC on generation of DC via activation of the ERK or p38 mitogen activated protein kinase pathway. It is concluded that HUVEC are involved in DC development and can suppress the differentiation of monocyte to DC.

Activated T cells promote differentiation of mesenchymal stem cells into osteoblasts / 中国实验血液学杂志

This study was aimed to investigate the effect of activated T cell on the ability of MSC to differentiate into osteoblasts. The activated T cells with MSCs were co-culture for 14 days, then the osteoblast formation was tested by alkaline phosphatase staining. Furthermore, the supernatant of activated T cell was added in culture system of MSCs, the expression of molecules related with immune regulation of activated T cells was detected by RT-PCR, so as to determine what kinds of cytokine displayed the important function in MSC differentiation. The result showed that activated T cell could promote differentiation of MSC into osteoblasts, and IL-1beta played an important role in the effect of activated T cells on MSCs, while TNF-alpha, TGF-beta1 were not. It is concluded that the activated T cells promote the differentiation of MSCs to osteoblasts. The interactive influence between MSCs and immune cells can be mediated through cytokines.

Effects of human dendritic cells derived from CD34(+) cells on the biologic characteristic of bone marrow-derived mesenchymal stem cells / 中国实验血液学杂志

This study was purposed to clarify whether biology function of mesenchymal stem cells (MSCs) is changed by suppressing the development of dendritic cells (DC) derived from hematopoietic stem cells (HSCs). MSCs were cocultured with dendritic cells derived from CD34 positive hematopoietic stem cells (HSCs), and then the expression of cytokines and phenotypes of DCs/MSCs were detected by RT-PCR and flow cytometry respectively. Induced experiments were used to analyze the differentiation ability of MSCs. The results showed that DCs/MSCs were negative for the CD14, CD34, CD45, CD31, CD86, but positive for HLA-ABC, CD29, CD73, though the percentage decreased as MSCs vs DCs/MSCs (93.1% vs 13.44%, 98.3% vs 78.8%, 95.3% vs 75.9%). In addition, the expression of cytokines such as M-CSF, TGF-beta increased in DCs/MSCs. After differentiation induction, DCs/MSCs were deprived of the potential to differentiate into adipocytes, but maintained osteogenesis characteristics. It is concluded that the basic characteristics of MSCs are altered after coculture with DCs, and DCs/MSCs result in lower expression of mesenchymal phenotypes and decrease differentiation ability, but increase the expression of cytokines related to hematopoiesis and immunity.

Mesenchymal stem cells in hematopoietic regulation--review / 中国实验血液学杂志

As the progenitor of most cell components in the hematopoietic microenvironment, mesenchymal stem cells (MSC) exhibit self-renewal and multilineage differentiation capacity. Through direct interaction with hematopoietic cells, secreting extracellular matrix and factors, MSC maintain the integrity of hematopoietic microenvironment and regulate hematopoiesis accurately. This review summarized the function of MSC in hematopoietic regulation, such as secretion of cytokines supporting hematopoiesis, MSC expression and adhesion molecules interacting with hematopoietic cells, and supportive effects of transplantation combining MSC with HSC on hematopoietic reconstruction, and its clinical perspectives.