Endothelial progenitor cells are precursors of endothelial cells, which are able to differentiate into mature endothelial cells. Studies are needed to increase more detailed understanding on the mechanisms of EPC-differentiation, survival, homing and distribution of the tissue. The human EPC has potential to be used as diagnostic and prognostic or therapeutic tools in the future. This review describes recent studies on the biological characteristics and clinical application of EPC, including immunophenotype and functional characteristics of EPCs, mobilization, release and differentiation of EPCs, EPC number and recruitment, clinical application of EPCs, and so on.
Endothelial Cells ; cytology ; Humans ; Stem Cells ; cytology

Endothelial colony-forming cells (ECFCs), different from classical endothelial progenitor cells, are late endothelial progenitor cells with the capability to promote angiogenesis. Recent studies showed that ECFCs have a huge angiogenesis potential in the restoration of ischemic hearts, lungs or brains. They are also able to induce the expression of vascular related factor to promote angiogenesis in repair of limb ischemia or bone injury. Furthermore, ECFCs possess a strong homing effect for tumor, which is closely related to tumor occurrence, development and prognosis. Thus, ECFCs are a novel direction for vascular regeneration study, and may lead to ground-breaking progresses in fields of tissue regeneration and tumor.
Endothelial Cells ; cytology ; Humans ; Ischemia ; Neovascularization, Physiologic ; Stem Cells ; cytology

Cellular Microenvironment ; Endothelial Cells ; cytology ; Hematopoietic Stem Cells ; cytology

Cells, Cultured ; Endothelial Cells ; cytology ; Humans ; Stem Cells

Animals ; Endothelial Cells ; cytology ; Hepatocytes ; cytology ; Humans ; Liver Regeneration

OBJECTIVETo investigate the possibility of directional differentiation of human adipose stem cells (hADSCs) into endothelial cells (EC), so as to provide seed cells for tissue engineered vessels.

METHODShADSCs were isolated from human adipose tissue by collagenase digestion, cultured and amplified by adherence to flasks. Then hADSCs were directionally induced to differentiate into EC by a combination of fibronectin (FN), endothelial cells support liquid (EGM2-MV) containing various growth factors and high concentration of VEGF165 (50 ng/ml). Then, the cells morphology, phenotype and function were identified.

RESULTSHighly homologous hADSCs were obtained, and then hADSCs were directionally differentiated into EC. CD31 and CD34, the specific markers for EC, and vascular endothelial growth factor receptor (KDR) were positive by immunohistochemical staining and RT-PCR. In addition, unique Weibel-Palade bodies in EC were observed under transmission electron microscope. Functionally, hADSCs could swallow Dil-Ac-LDL and form tube-like structures in matrigel after endothelial differentiation.

CONCLUSIONShADSCs can be successfully induced to differentiate into endothelial cells in vitro.

Adipocytes ; cytology ; Cell Differentiation ; Cells, Cultured ; Endothelial Cells ; cytology ; Humans ; Stem Cells ; cytology ; Tissue Engineering

The conductance measurement method of endothelial permeability has been established by the principle that there is direct ratio between conductance and filter area, and has been compared with the albumin filter method. The results show that there is close correlation between conductance and filter area, the conductance measurement can be used for the detection of the monolayer endothelial cells permeability. The combination of the conductance measurement and the albumin filter measurement method can accurately reflect the permeability change in severity and scope.
Cell Culture Techniques ; Cells, Cultured ; Endothelial Cells ; cytology ; Humans ; Permeability

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.
Cell Differentiation ; Coculture Techniques ; Dendritic Cells ; cytology ; Human Umbilical Vein Endothelial Cells ; cytology ; Humans ; Monocytes ; cytology

Bone marrow mensenchymal stem cells (BM-MSCs) are capable of supporting the survival, differentiation and migration of hematopoietic stem cell, and have a profound application prospect in transplantation and treatment of graft-versus-host disease (GVHD). This review aims to illustrate the interaction between BM-MSCs and other intra-bone marrow cells, including hematopoietic stem cells, endothelial cells and osteoblasts. The investigation of their regulating mechanism will help better understanding of the BM-MSCs' role in hematopoiesis.
Bone Marrow Cells ; cytology ; Cell Communication ; physiology ; Endothelial Cells ; cytology ; Humans ; Mesenchymal Stromal Cells ; cytology ; Osteoblasts ; cytology

AIMTo analyze gene expression difference between human mesenchymal stem cells and umbilical vein endothelial cells, to discuss the feasibility of inducing hMSCs to differentiate into endothelial cells through in vitro gene transfection as well as the use and prospective as a seeding cell source of vascular tissue engineering.

METHODShMSCs and hUVECs were isolated, expanded in culture, and characterized by flow-cytometry, immunocytochemistry, immunofluorescence and transmission electron microscopy (TEM). Differential analysis of gene expression profiles between them was performed by Biostar H-40 cDNA microarrays. The properties of VEGF 165 transfected were also detected with RT-PCR, ELISA et al.

RESULTSNearly 86% genes were coexpressed in both cells and hMSCs expressed typical endothelial antigen marker of EC. After VEGF165 transfection, hMSCs (or committed hMSCs) were positive for CD31. To different extent, the expression of CD44 was down regulated and CD34, FVIIIAg, Flt-1 up regulated.

CONCLUSIONGeneration of functional EC or tissue engineered blood vessels from human MSCs is feasible utilizing an in vitro environment gene transfection.

Bone Marrow Cells ; cytology ; Cell Differentiation ; Cells, Cultured ; Endothelial Cells ; cytology ; Endothelium, Vascular ; cytology ; Humans ; Mesenchymal Stromal Cells ; cytology ; Transfection ; Vascular Endothelial Growth Factor A ; administration & dosage