Large Number Of Endothelial Cells Research Articles

Preliminary Results of Single-cell Transcriptome Sequencing in Renal Arterial Lesions of Takayasu Arteritis

Objective To explore the preliminary application of single-cell RNA sequencing (scRNA-seq) in the renal arterial lesions in Takayasu arteritis (TA) patients. Methods This study included 2 TA patients with renal artery stenosis treated by bypass surgery in the Department of Vascular Surgery,Beijing Hospital.The obtained 2 renal artery samples were digested with two different protocols (GEXSCOPE kit and self-made digestion liquid) before scRNA-seq and bioinformatics analysis. Results A total of 2920 cells were obtained for further analysis.After unbiased cluster analysis,2 endothelial cell subsets,2 smooth muscle cell subsets,1 fibroblast subset,2 mononuclear macrophage subsets,1 T cell subset,and 1 undefined cell subset were identified.Among them,the two subsets of smooth muscle cells were contractile and secretory,respectively.The results of scRNA-seq indicated that enzymatic hydrolysis with GEXSCOPE kit produced a large number of endothelial cells (57.46%) and a small number of immune cells (13.21%).However,immune cells (34.64%) were dominant in the cells obtained by enzymatic hydrolysis with self-made digestive liquid. Conclusion scRNA-seq can be employed to explore the cellular heterogeneity of diseased vessels in TA patients.Different enzymatic digestion protocols may impact the proportion of different cells.

Studying endothelial cell shedding and orientation using adaptive perfusion-culture in a microfluidic vascular chip.

Most tissue-engineered blood vessels are endothelialized by static cultures in vitro. However, it has not been clear whether endothelial cell-shedding and local damage may occur in an endothelial layer formed by static cultures under the effect of blood flow shear postimplantation. In this study, we report a bionic and cost-effective vascular chip platform, and proved that a static culture of endothelialized tissue-engineered blood vessels had the problem of a large number of endothelial cells falling off under the condition imitating the human arterial blood flow, and we addressed this challenge by regulating the flow field in a vascular chip. Electrospun membranes made of highly oriented or randomly distributed poly(ε-caprolactone) fibers were used as the vascular scaffolds, on which endothelial cells proliferated well and eventually formed dense intima layers. We noted that the monolayers gradually adapted to the artery-like microenvironment through the regulation of chip flow field, which also revealed improved cellular orientations. In conclusion, we have proposed a vascular chip with adaptive flow patterns to gradually accommodate the statically cultured vascular endothelia to the shear environment of arterial flow field and enhanced the orientation of the endothelial cells. This strategy may find numerous potential applications such as screening of vascular engineering biomaterials and maturation parameters, studying of vascular biology and pathology, and construction of vessel-on-a-chip models for drug analysis, among others.

Effects and mechanism of rat epidermal stem cells treated with exogenous vascular endothelial growth factor on healing of deep partial-thickness burn wounds in rats

Effects and mechanism of rat epidermal stem cells treated with exogenous vascular endothelial growth factor on healing of deep partial-thickness burn wounds in rats

Efficient isolation and identification of primary endothelial cells from bovine aorta by collagenase P

Introduction: Endothelial cells are widely used among researchers for investigation of cardiovascular diseases, particularly atherosclerosis. Since aortic endothelial cells are able to be cultured in high passages, these cells are suitable for physiological and pathological studies of blood vessels. Objectives: The aim of this study was employing a digestion method to isolate the endothelial cells from bovine aorta by utilizing collagenase P and, establishing and characterizing isolated primary endothelial cells (IPECs) cultures. Materials and Methods: IPECs were isolated from fresh bovine aorta via enzymatic digestion method using collagenase P. Cell morphology and its functions were assessed by measuring the gene expression of endothelial nitric-oxide synthase (eNOS) and endothelin-1. In order to validate them as IPECs, they were compared with bovine aortic endothelial cells (BAECs) and vascular smooth muscle cells (VSMCs). Effects of synthetic endothelin-1 (100 nm) were assessed on the phosphorylation of Smad2 transcription factor via western blotting in IPECs for periods of one to four hours. Results: In this study, the morphology of IPECs from bovine aorta was identical to that of the BAECs. The gene expressions of endothelin-1 and eNOS were higher than those of BAECs and VSMCs. In addition, synthetic endothelin-1 resulted in the time-dependent boost of phosphorylation of carboxy-terminal Smad2 in the IPECs for periods of two and four hours. Conclusion: The results of this study confirm the efficacy of the enzymatic digestion method in isolating a large number of endothelial cells with morphological and functional characteristics.

Identification of target cells of a European equine arteritis virus strain in experimentally infected ponies

Currently, little is known on the cellular pathogenesis of equine arteritis virus (EAV). The purpose of the present study was to identify the target cells in ponies experimentally inoculated with EAV 08P178 (EU, clade-1). EAV-target organs (respiratory tissues with associated lymphoid tissues and large intestines), collected at 3 and 7 days post inoculation (dpi) and with virus titers≥105.0 TCID50/g, were processed with double immunofluorescence staining for the simultaneous detection of EAV N-protein and one of the following cell markers: CD172a (myeloid cells), CD3 (T lymphocytes), IgM (B lymphocytes) and von Willebrand factor (endothelial cells). In the different analyzed organs, 31–58% and 47–63% of the EAV-positive cells were mononuclear leukocytes (mainly CD172a+ followed by CD3+) at 3 and 7 dpi, respectively. EAV-positive endothelial cells were not detected in 3.200 large blood vessels (≥3 endothelial cells/vessel cross section). However, in terminal capillaries (1–2 endothelial cells/vessel cross section) of the different organs, 15–51% of the endothelial cells were EAV-positive. In conclusion, the present study demonstrates that EAV 08P178 (i) has a main tropism for CD172a+ and CD3+ mononuclear leukocytes and (ii) infects a large number of endothelial cells in terminal capillaries. EAV 08P178 infection in capillaries is most probably the cause of an increased vascular permeability leading to leakage of fluid (edema-serous exudate) but not to severe vasculitis and hemorrhages.

The long‐term stability in gene expression of human endothelial cells permits the production of large numbers of cells suitable for use in regenerative medicine

Tissue engineering has been conducted in the study of cardiovascular grafts for many years. Many obstacles have been overcome in this rapidly changing field, but one difficulty has remained until now: the large number of endothelial cells (ECs) needed for seeding the inner layer of bypass graft. Recent advances in endothelial progenitor cell (EPC) isolation and culture techniques have increased the interest in genetic studies. Despite these advances in EPC studies, the "gold standard" for the seeding of tissue engineering constructs or hybrid grafts remains mature human umbilical vein endothelial cells (HUVECs). This study investigates the ability of HUVECs to be expanded in culture to provide sufficient cells for graft seeding. The levels of gene expression of key genes are then examined to ensure that these cells retain the EC phenotype. This study demonstrates that HUVECs may be cultured for up to 12 passages without alteration in phenotype. Subsequent passage numbers are sufficiently similar to those preceding them to allow cells of different passages to be mixed without gene expression anomalies.

Cytokine regulation networks in the cancer microenvironment

During carcinoma formation, cancer cells release various cytokines and growth factors into their surroundings and recruit and reprogram many other types of cells in order to establish a tumor microenvironment. Consequently, the tumor tissues almost always contain a large number of endothelial cells, fibroblasts, and infiltrating inflammatory cells that in turn produce a variety of cytokines. The cytokines produced by these cells have been posited as key factors in modulating immune response either against or in favor of tumorigenesis in the microenvironment. The interactions that take place between immune and cancer cells are complex, involving multiple cascades of cytokines, chemokines, and/or growth factors. In this review, we address the essential pro- and anti-tumorigenic roles of cytokines in the tumor microenvironment. As the interaction of cytokines, growth factors, and cancer cells forms a comprehensive network at the tumor site that is then responsible for the overall progression or rejection of the tumor, the current review links the microenvironment-derived cytokines and growth factors to a number of different kinds of human carcinogenesis models. Multifunctional cytokines, extracellular matrix mediators, and regulatory cytokines in the cancer environment are all shown to be key factors in the different cancer immune-editing systems. The characterization of cytokine networks in various types of cancer cells may yield important information for understanding the immune-related mechanisms of cancer development, and this knowledge may have subsequent application in cancer immunotherapy.

Circulating progenitor cells regenerate endothelium of vein graft atherosclerosis, which is diminished in ApoE-deficient mice.

Previously we showed that a large number of endothelial cells in vein grafts undergo apoptosis or necrosis during the first few days followed by endothelial regeneration. In the present study, we investigated endothelial cell death and regeneration in vein grafts using transgenic mice carrying LacZ genes driven by an endothelial TIE2 promoter. When a vein fragment from TIE2-LacZ was isografted into the carotid artery of wild-type mice, the number of beta-gal+ cells were reduced at 3 days and disappeared completely by 4 weeks after grafting. Conversely, beta-gal+ cells were observed on the surface of vein segments donated by wild-type mice isografted into TIE2-LacZ mice at 1 week and reached confluence by 4 weeks, suggesting recipient origins of endothelial cells. Interestingly, beta-gal+ cells were evenly distributed on the surface of the whole vein segment grafted into TIE2-LacZ mice, indicating a contribution of circulating progenitor cells. When wild-type veins were grafted into a chimeric mouse carrying TIE2-LacZ genes in bone marrow cells, a proportion of cells displayed a beta-gal+ staining. Furthermore, the number of CD34+ and Flk+ progenitor cells in blood of apoE-deficient mice were significantly lower than those of wild-type controls, which coincided with diminished beta-gal+ endothelial cells on the surface of vein grafts in TIE2-LacZ/apoE-/- mice. Thus, we provide the first evidence that endothelial cells of vein grafts are derived from circulating progenitor cells, of which one-third are derived from bone marrow progenitor cells. Hyperlipidemia due to apoE deficiency results in a lower number of endothelial progenitors in blood and correlated with enhanced atherosclerosis. The full text of this article is available online at http://www.circresaha.org.

Divergent vascular mechanisms downstream of Sry establish the arterial system in the XY gonad.

Although the primitive vasculature is identical in XX and XY genital ridges until 11.5 days postcoitum (dpc), by 12.5 dpc the XY gonad develops a distinct vasculature. This male-specific vasculature, which includes the development of a large coelomic vessel, develops coincident with expression of Sry and formation of testis cords. We show that similar levels of proliferation and vasculogenesis expand the primary vasculature in XX and XY gonads. However, soon after Sry expression begins, the XY gonad recruits a large number of endothelial cells from the adjacent mesonephros, a mechanism totally absent in XX gonads. These migrating cells do not contribute to venous or lymphatic development. Instead, these cells contribute to the arterial system, as indicated by expression of ephrinB2 and by elements of the Notch signaling pathway. This newly formed arterial system establishes a new pattern of blood flow in the XY gonad, which we speculate may have an important role in export of testosterone to masculinize the XY embryo.

Comparative Endothelial Biomicroscopy

Calibrating comparative endothelial biomicroscopy with a corneal endothelial microscope (Heyer-Schulte Medical Optics), we have obtained clinically useful estimates of endothelial cell density. This simple and inexpensive technique allows rapid examination and evaluation of a large number of endothelial cells across various corneal diameters. It is, however, a clinical rather than investigative procedure and is not intended to replace the quantitative features of endothelial specular photomicrography for scientific studies.

The Effects of Beta Radiation on the Normal Corneal Endothelium of the Rabbit

No pathologic effects were noted in the eyes after local Sr/sup 90/ irradiation of the central areas of the right eye at doses of 6000 and 18,000 rep. Combined alizarin red and hematoxylin stains of the endothelium were used to study changes in the population of multinucleated giant cells, which were observed in the normal corneal endothelium of the control left eye. After doses of 6000 rep, the difference of multinucleated giant cell counts between the two eyes was within the normal limit for the first day, followed by a period of 3 to 7 days during which the formation of these cells in the irradiated eyes was temporarily inhibited. After this period of inhibition, an overcompensating increase of these cells was noted in the third postirradiation week, reaching its peak in the fourth week. By the end of the sixth week this effect had tapered off. After doses of 18,000 rep, the difference of the multinucleated giant cell counts between the two eyes was within the normal limit for the first day. A decrease in the number of these cells was noted in the irradiated eyes 3 days after irradiation. After this period of inhibition, an increase of thesemore » cells was noted in the first postirradiation week and the count rose consistently to the 6-week period when the experiments were terminated. Cytologic changes in the corneal endothelium were noted only in the doses of 18,000 rep in the 4- and 6- week period after irradiation but the extent of the cellular damage is not sufficient to cause biomicroscopically visible corneal lesions. No pathologic mitoses or nuclear fragmentation were observed with the doses and time intervals used. Perhaps insufficiently high doses of radiation were used to demonstrate these changes, especially in mitoses which almost always are limited to the peripheral endothelium. It is concluded that a BETA -ray dose of 18,000 rep is still not high enough to damage a large number of endothelial cells and, when only a few cells are damaged, these may eventually be replaced or, if the damage to a cell is not severe, recovery is possible. (BBB)« less