ObjectiveTo explore optimal conditions of isolation, culture and labeled with superparamagnetic iron oxide (SPIO) in vitro of rat bone marrow endothelial progenitor cells, and lay the foundations for the further EPCs tracer study in vivo. MethodsThe EPCs derived from rat bone marrow were isolated and cultured by using density gradient centrifugation, which were labeled with different concentrations SPIO, Prussian blue staining was used to detect the cells labeling rate, MTT assay was used to detect the cells proliferation activity, and Trypan blue staining was used to detect the cells vitality. ResultsEPCs gradually growed in monolayer arrangement about 7 d after cultured. When the concentration of SPIO was 50μg/mL, the highest labeling rate of Prussian blue staining was 90%, the growth state of labeled EPCs were good, and could normal adherent growth and passage. At this time, the cell viability and proliferation activity were the highest through trypan blue staining and MTT assay. ConclusionsEPCs can be labeled with SPIO easily and efficiently when the concentration was 50μg/mL?without interference on the viability and proliferation activity, which lay the foundations for the further EPCs tracer study in vivo.
Objective To investigate the effects of titanium modified by ultrasonic acid etching/anodic oxidation (UAT) loaded with endothelial progenitor cells-exosome (EPCs-exo) on proliferation and osteogenic and angiogenic differentiations of adipose-derived stem cells (ADSCs). Methods The adipose tissue and bone marrow of 10 Sprague Dawley rats were harvested. Then the ADSCs and EPCs were isolated and cultured by collagenase digestion method and density gradient centrifugation method, respectively, and identified by flow cytometry. Exo was extracted from the 3rd to 5th generation EPCs using extraction kit, and CD9 and CD81 were detected by Western blot for identification. The three-dimensional printed titanium was modified by ultrasonic acid etching and anodic oxidation to prepare the UAT. The surface characteristics of UAT before and after modification was observed by scanning electron microscopy; UAT was placed in EPCs-exo solutions of different concentrations (100, 200 ng/mL), and the in vitro absorption and release capacity of EPCs-exo was detected by BCA method. Then, UAT was placed in DMEM medium containing different concentrations of EPCs-exo (0, 100, 200 ng/mL), and co-cultured with the 3rd generation ADSCs to construct UAT-ADSCs-exo. Cell morphology by laser confocal microscopy, live/dead cell staining, and cell proliferation were observed to evaluate biocompatibility; alkaline phosphatase (ALP) staining and alizarin red staining, RT-PCR detection of osteogenesis-related genes [osteocalcin (OCN), RUNT-related transcription factor 2 (Runx2), ALP, collagen type 1 (COL-1)] and angiogenesis-related gene [vascular endothelial growth factor (VEGF)], immunofluorescence staining for osteogenesis (OCN)- and angiogenesis (VEGF)-related protein expression were detected to evaluate the effect on the osteogenic and angiogenic differentiation ability of ADSCs. Results Scanning electron microscopy showed that micro-nano multilevel composite structures were formed on the surface of UAT. About 77% EPCs-exo was absorbed by UAT within 48 hours, while EPCs-exo absorbed on the surface of UAT showed continuous and stable release within 8 days. The absorption and release amount of 200 ng/mL group were significantly higher than those of 100 ng/mL group (P<0.05). Biocompatibility test showed that the cells in all concentration groups grew well after culture, and the 200 ng/mL group was better than the other groups, with fully spread cells and abundant pseudopodia, and the cell count and cell activity were significantly higher than those in the other groups (P<0.05). Compared with the other groups, 200 ng/mL group showed enhanced ALP activity and mineralization ability, increased expressions of osteogenic and angiogenic genes (OCN, Runx2, COL-1, ALP, and VEGF), as well as increased expressions of OCN and VEGF proteins, with significant differences (P<0.05). Conclusion EPCs-exo can effectively promote the adhesion, proliferation, and osteogenic and angiogenic differentiation of ADSCs on UAT surface, the effect is the most significant when the concentration is 200 ng/mL.
Objective To establish the three diamension-model and to observe the contribution of endothelial progenitor cell (EPC) in the angiogenesis and its biological features. MethodsEPC was obtained from the rats’ peripheral blood. Its cultivation and amplification in vitro were observed, and the function of the cultural EPC in vitro was detected. The three diamension-model was established and analyzed. ResultsEPC was obtained from the peripheral blood successfully. The proliferation of the EPC which induced with VEGF(experimental group) was better than that without VEGF （control group） at every different phase (P＜0.01). It was found that EPC grew into collagen-material from up and down in the three diamension-model, and its pullulation and infiltration into the collagen were seen on day 1 after cultivation. With the time flying, there were branch-like constructions which were vertical to the undersurface of collagen and interlaced to net each other. It showed that in experimental group the EPC grew fast, its infiltration and pullulation also were fast, the branch-like construction was thick. But in control group, the EPC grew slowly, infiltration and pullulation were slow, the branch-like construction was tiny and the depth of infiltration into collagen was superficial. The number of new vessels in experimental group was larger than that in the control group at every different phase (P＜0.01). ConclusionRat tail collagen can induce EPC involved in immigration, proliferation and pullulation in angiogenesis. The three-diamension model of EPC can be used to angiogenesis research. VEGF can mobilize and induce EPC to promote the angiogenesis.
Objective To measure the level of circulating endothelial progenitor cells ( EPCs) in peripheral blood of patients with acute exacerbation of chronic obstructive pulmonary disease ( AECOPD) , and to explore the relationship between EPCs and severity markers of the disease and cardiovascular adverse outcome predictors.Methods Forty patients with COPD were recruited, including 27 at acute exacerbation phase and 13 with stable COPD from December 2010 to December 2011. Sixteen healthy nonsmokers were included as controls. Circulating EPCs were isolated by Ficoll density-gradient centrifugation and purified by Magnetic Activated Cell Sorting system. High-sensitivity C-reactive protein ( hsCRP) was estimated by using a latex immunoturbidimetric assay kit, and matrix metalloproteinase-9 ( MMP-9) was measured by enzymelinked immunosorbent assay ( ELISA) . Arterial blood gas analysis and echocardiograph were performed in the AECOPD patients. The correlations between circulating EPCs, lung function, and cardiovascular markers were investigated. Results Circulating EPCs were significantly lower in AECOPD and stable COPD patients compared with the healthy controls [ ( 5.1 ±2.6) ×103 /mL and ( 6.0 ±3.2) ×103 /mL vs. ( 9.0 ±4.3) × 103 /mL, Plt;0. 05] . EPCs had a weak correlation with hsCRP ( P = 0. 033) , but not with MMP-9. In the AECOPD patients, EPC counts were significantly inversely correlated with PASP ( pulmonary artery systolic pressure) and NT-proBNP ( amino-terminal pro-brain natriuretic peptide) levels, and positively with left ventricular ejection fraction. No correlations were found between EPCs and lung function, blood gas, hospital stays or smoking index. Conclusions Circulating EPCs were significantly lower in AECOPD patients compared with healthy controls, in which systemic inflammation might be involved. Decreased EPCs were correlated with cardiac dysfunction in patients with AECOPD, which may account for the increased cardiovascular risk in this population.
ObjectiveTo compare the biological features of early and late endothelial progenitor cells (EPCs) by isolating and culturing early and late EPCs from the human peripheral blood so as to find some unique properties of EPCs and to propose a suitable strategy for EPCs identification. MethodsMononuclear cells were isolated from the human peripheral blood using density gradient centrifugation. Then, the cells were inoculated in human fibronectin-coated culture flasks and cultured in endothelial cell basal medium 2. After 4-7 days and 2-3 weeks culture, early and late EPCs were obtained respectively. The morphology, proliferation potential, surface markers, cytokine secretion, angiogenic ability, and nitric oxide (NO) release were compared between 2 types of EPCs. Meanwhile, the human aortic endothelial cells (HAECs) were used as positive control. ResultsThe morphology of early and late EPCs was different:early EPCs formed a cell cluster with a spindle shape after 4-7 days of culture, and late EPCs showed a cobblestone appearance. Late EPCs were characterized by high proliferation potential and were able to form capillary tubes on Matrigel, but early EPCs did not have this feature. Both types EPCs could ingest acetylated low density lipoprotein and combine with ulex europaeus Ⅰ. Flow cytometry analysis showed that early EPCs did not express CD34 and CD133, but expressed the CD14 and CD45 of the hematopoietic stem cell markers;however, late EPCs expressed CD31 and CD34 of the endothelial cell markers, but did not express CD14, CD45, and CD133. By RT-PCR analysis, the expressions of vascular endothelial growth receptor 2 and vascular endothelial cadherin in early EPCs were significantly lower than those in the late EPCs and HAECs (P<0.05), but no significant difference was found in the expression of von Willebrand factor and endothelial nitric oxide synthase (eNOS) between 2 type EPCs (P>0.05). The concentrations of vascular endothelial growth factor, granulocyte colony-stimulating factor, and interleukin 8 were significantly higher in the supernatant of early EPCs than late EPCs (P<0.05). Western blot assay indicated eNOS expressed in both types EPCs, while the expression of eNOS in late EPCs was significantly higher than early EPCs at 5 weeks (P<0.05). Both cell types could produce similar amount of NO (P>0.05). ConclusionThe expression of eNOS and the production of NO could be used as common biological features to identify EPCs, and the strategy of a combination of multiple methods for EPCs identification is more feasible.
Coronary heart disease is a kind of heart disease that is caused by atherosclerosis.The lipid deposition in the vessel wall results in occlusion of coronary artery and stenosis, which could induce myocardial ischemia and oxygen deficiency. Intervention therapies like percutaneous coronary intervention (PCI) and coronary stent improve myocardial perfusion using catheter angioplasty to reduce stenosis and occlusion of coronary artery lumen. Accordingly, intervention therapies are widely applied in clinic to treat ischemic cardiovascular disease, arterial intima hyperplasia and other heart diseases, which could save the patients′ life rapidly and effectively. However, these interventions also damage the original endothelium, promote acute and subacute thrombosis and intimal hyperplasia, and thus induce in stent restenosis (ISR) eventually. Studies indicated that the rapid reendothelialization of damaged section determined postoperative effects. In this review, reendothelialization of implants after intervention therapy is discussed, including the resource of cells contributed on injured artery, the influences of implanted stents on hemodynamic, and the effects of damaged degree on reendothelialization.
ObjectiveTo observe the effects of aquaporin 1 (AQP1) on the proliferation and migration of endothelial progenitor-endothelial progenitor cells (EPC).MethodsBone marrow cells of AQP1 wild-type (WT) (n=6) and knockout-type (KO) mice (n=6) were isolated and differentiated into EPC in vitro. Immunofluorescence was used to detect cell surface antigens to identify EPC. Live cell kinetic imaging and quantification technology, transwell migration assays, as well as scratch test were used to compare the function of EPC between AQP1 WT and KO mice.ResultsEPC culture showed that cells were initially suspended and gradually adhered to typical mesenchymal stem cells within 7 days. After cultured on special medium for endothelial cells they were adhered and differentiated, and fusiform or polygonal, paving stone-like EPC were observed around 14 days. When cultured by special medium of EPC, CD133 and CD31 were positively detected after 7 days, and CD34 and Flk-1 were positively detected after 14 days. Positive expression of AQP1 was only detected in EPC of AQP1 WT mice. Functional studies of EPC revealed there was no significant difference in the proliferation of EPC between AQP1 WT and KO group mice. Transwell assay showed that EPC migration ability of AQP1 KO mice was significantly weaker than that of WT mice. The scratch healing ability of EPC in AQP1 KO mice was significantly lower than that of WT mice.ConclusionsEPC initially shows the characteristics of stem cells and with the prolongation of culture time, EPC gradually shows the characteristics of endothelial cells. AQP1 affects the EPC migration rather than proliferation.
Immobilization of CD34 antibody on ferroferric oxide magnetic nanoparticles was achieved by the traditional carboxyl-amine conjugation reaction. Fourier transform infrared spectroscopy (FT-IR), nanoparticle size analysis (dynamic light scattering and transmission electron microscope), and other testing methods were used to detect the surface modified magnetic nanoparticles. The endothelial progenitor cells (EPCs) were cultured with the surface modified magnetic nanoparticles to evaluate cell compatibility and the combination effect of nanoparticles on EPCs in a short period of time. Directional guide of the surface modified magnetic nanoparticles to EPCs was evaluated under applied magnetic field and simulated dynamic flow condition. The results showed that the magnetic nanoparticles were successfully modified with CD34 antibody, which had good cell compatibility within a certain range of the nanoparticle concentrations. The surface modified nanoparticles can combine with EPCs effectively in a short time, and those nanoparticles combined EPCs can be directional guided under the magnetic field in the dynamic flow environment.
Endometriosis (EM) is a common benign gynecological disease with complex pathogenesis and lack of unified understanding. In recent years, the theory of stem/progenitor cells has gradually been recognized by scholars. The presence of stem/progenitor cells in the endometrium and researchers’ understanding of stem/progenitor cell specific markers has been further developed, which is of great significance for sorting stem/progenitor cells and further elucidating their roles in the pathogenesis of EM. At present, more endometrial stem cell signaling pathways have been studied including Wnt, Hedgehog, Notch, phosphatidylinositol-3-kinase/protein kinase B, Smad/connective tissue growth factor, CXCL12/CXCR4, etc. These signaling pathways can regulate stem cell involvement in the pathogenesis of EM. Exploring how signaling pathways to regulate stem cell involvement in the pathogenesis of EM can help elucidate the specific pathogenesis of EM and provide new directions for its treatment. This paper will summarize them.
Objective To observe the effects of Galectin-3 on proliferation of vascular endothelial cells derived from peripheral blood endothelial progenitor cells. Methods The cultured peripheral blood endothelial progenitor cells in vitro were isolated and purified from human peripheral blood, and the cells were differentiated into vascular endothelial cells. Then the cells were cultivated with the galectin-3 of different concentrations, and to observe the proliferation of endothelial cells derived from peripheral blood endothelial progenitor cells. Results The abilities of proliferation of endothelial cells derived from peripheral blood endothelial progenitor cells of 0.1, 1.0, 2.5, 5.0, and 10.0 μg/ml groups were higher than that of 0 μg/ml group, there were not statistic significance of the differences between the 0.1，1.0, 2.5, and 0 μg/ml groups （P＞0.05）. But the abilities of proliferation of 5.0 and 10.0 μg/ml groups were obviously higher than that of 0, 0.1, 1.0, and 2.5 μg/ml groups （P＜0.05）, and the abilities of proliferation of 10.0 μg/ml group was also higher than that of 5.0 μg/ml group （P＜0.05）. Conclusion Galectin-3 can promote the proliferation of endothelial cells derived from peripheral blood endothelial progenitor cell.