scholarly journals THE MIGRATION OF LYMPHOCYTES ACROSS THE VASCULAR ENDOTHELIUM IN LYMPHOID TISSUE

1972 ◽  
Vol 136 (3) ◽  
pp. 568-588 ◽  
Author(s):  
G. I. Schoefl ◽  
Keyword(s):  
Endothelial Cells ◽  
Vascular Endothelium ◽  
Lymphoid Tissue ◽  
Electron Microscope Study ◽  
Fluid Loss ◽  
Serial Sections ◽  
Lymphocyte Migration ◽  
Cell Cytoplasm ◽  
Endothelial Layer ◽  
Special Adaptation

An electron microscope study was made of the mode of lymphocyte migration across the endothelial layer of venules in the Peyer's patches of mice and rats. Single and serial sections were examined. Of a total of about 800 lymphocytes observed in single sections, 91% were located between endothelial cells and 9% were surrounded by endothelial cytoplasm in the particular plane of section. 62% of the lymphocytes occurred in groups of two or more. In long sequences of serial sections through 21 endothelial cells, all lymphocytes were located external to the endothelial cells though some appeared "internal" at certain levels of sectioning. The probability that a lymphocyte which appears to be surrounded by endothelial cell cytoplasm actually lies within the cell was analyzed with a mathematical model derived from data obtained from single sections. The results of this analysis suggested that at least 93–99% of lymphocytes (within 90% limits of confidence) take an intercellular path in their migration from blood to lymph. It is concluded that lymphocytes migrate across the vascular endothelium by insinuating themselves between endothelial cells and not by passing through them. Rather than constituting an increased barrier to cell migration, the unusual height of the endothelial cells in these vessels is interpreted to be a special adaptation which allows sustained cell traffic without excessive fluid loss taking place concomitantly.

The migration of lymphocytes through the endothelium of venules in lymph nodes: an electron microscope study

1964 ◽  
Vol 159 (975) ◽  
pp. 283-290 ◽  
Keyword(s):  
Endothelial Cells ◽  
Electron Microscope ◽  
Lymph Nodes ◽  
Electron Microscope Study ◽  
Large Scale ◽  
Intercellular Junctions ◽  
Thoracic Duct Lymph ◽  
Serial Sections ◽  
Duct Lymph ◽  
Pass Through

The post-capillary venules in the lymph nodes of rats have been examined with the electron microscope. The walls of these vessels normally contain many small lymphocytes, some of which are penetrating the endothelium while others are passing through the periendothelial sheath; most of the lymphocytes lie between the endothelium and the periendothelial sheath. No other leucocyte is normally present. The evidence suggests that these venules are normally the site of a large-scale migration of lymphocytes from the blood into the lymph nodes. A study of serial sections showed that lymphocytes migrate across the vessel wall by entering the endothelial cells and traversing their cytoplasm; they do not pass through the intercellular junctions. On the other hand, in inflamed lymph nodes polymorphs and monocytes emigrate through the venules by penetrating the junctions between endothelial cells. Some of the ‘large lymphocytes’ in thoracic duct lymph from normal rats were found to contain endoplasmic reticulum while others had a prominent Golgi complex.

PERSPECTIVES OF APPLICATION OF ANTIBODIES AGAINST ENDOGLIN (CD105) FOR VISUALIZATION AND ANTI-ANGIOGENE THERAPY OF TUMORS

2018 ◽  
Vol 64 (4) ◽  
pp. 504-507
Author(s):  
Vladimir Klimovich ◽  
Natalya Vartanyan ◽  
Anastasiya Stolbovaya ◽  
Lidiya Terekhina ◽  
Olga Shashkova ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Monoclonal Antibodies ◽  
Human Plasma ◽  
Vascular Endothelium ◽  
Immune Complexes ◽  
Targeted Delivery ◽  
Biological Fluids ◽  
Therapeutic Drugs ◽  
Cultured Endothelial Cells ◽  
Hybridoma Technology

During last years monoclonal antibodies (MAB) directed against vascular endothelium markers demonstrated their efficiency for visualization and targeted delivery of therapeutic drugs to tumors. Endoglin (CD105) which serves as a key element that determines endothelial cells quiescence or activation is one of such markers. Endoglin is highly expressed on the vascular endothelium of growing tumors. A first panel of MAB against endoglin in our country was produced at the hybridoma technology laboratory of RRC RST named after A.M. Granov. On the basis of these MAB ELISA was created allowing detection of endoglin in human plasma and other biological fluids. Several MAB had been shown to bind endoglin on the membrane of the cultured endothelial cells and to persist there for several hours. During the first 30 min after binding some of the immune complexes “endoglin-MAB” were internalized into the cytoplasm and were found included in the endosomes. In future these MAB can be used to create the reagents for the addressed delivery of isotope tags both on the membrane and into the cytoplasm of endothelial cells.

Deoxycholic acid enhancement of lymphocyte migration through direct interaction with the intestinal vascular endothelium

2021 ◽  
Author(s):  
Naoki Shibuya ◽  
Masaaki Higashiyama ◽  
Yoshihiro Akita ◽  
Kazuhiko Shirakabe ◽  
Suguru Ito ◽  
...  
Keyword(s):  
Vascular Endothelium ◽  
Deoxycholic Acid ◽  
Direct Interaction ◽  
Lymphocyte Migration

Glycocalyx modulates the motility and proliferative response of vascular endothelium to fluid shear stress

2007 ◽  
Vol 293 (2) ◽  
pp. H1023-H1030 ◽  
Author(s):  
Yu Yao ◽  
Aleksandr Rabodzey ◽  
C. Forbes Dewey
Keyword(s):  
Endothelial Cells ◽  
Vascular Endothelium ◽  
Fluid Shear Stress ◽  
Vascular Endothelial Cells ◽  
Surface Profile ◽  
Cell Junctions ◽  
Vascular Endothelial ◽  
Fluid Shear ◽  
New Perspective ◽  
Cell Cell

Flow-induced mechanotransduction in vascular endothelial cells has been studied over the years with a major focus on putative connections between disturbed flow and atherosclerosis. Recent studies have brought in a new perspective that the glycocalyx, a structure decorating the luminal surface of vascular endothelium, may play an important role in the mechanotransduction. This study reports that modifying the amount of the glycocalyx affects both short-term and long-term shear responses significantly. It is well established that after 24 h of laminar flow, endothelial cells align in the direction of flow and their proliferation is suppressed. We report here that by removing the glycocalyx by using the specific enzyme heparinase III, endothelial cells no longer align under flow after 24 h and they proliferate as if there were no flow present. In addition, confluent endothelial cells respond rapidly to flow by decreasing their migration speed by 40% and increasing the amount of vascular endothelial cadherin in the cell-cell junctions. These responses are not observed in the cells treated with heparinase III. Heparan sulfate proteoglycans (a major component of the glycocalyx) redistribute after 24 h of flow application from a uniform surface profile to a distinct peripheral pattern with most molecules detected above cell-cell junctions. We conclude that the presence of the glycocalyx is necessary for the endothelial cells to respond to fluid shear, and the glycocalyx itself is modulated by the flow. The redistribution of the glycocalyx also appears to serve as a cell-adaptive mechanism by reducing the shear gradients that the cell surface experiences.

scholarly journals Lymphocyte Homing to Bronchus-associated Lymphoid Tissue (BALT) Is Mediated by L-selectin/PNAd, α4β1 Integrin/VCAM-1, and LFA-1 Adhesion Pathways

2003 ◽  
Vol 197 (10) ◽  
pp. 1255-1267 ◽  
Author(s):  
Baohui Xu ◽  
Norbert Wagner ◽  
Linh Nguyen Pham ◽  
Vincent Magno ◽  
Zhongyan Shan ◽  
...  
Keyword(s):  
Immune Responses ◽  
Lymphoid Tissue ◽  
Lymphoid Tissues ◽  
Lymphocyte Migration ◽  
High Endothelial Venules ◽  
Level Of Involvement ◽  
Selectin Ligand ◽  
High Level ◽  
Migration Pathways ◽  
B And T Lymphocytes

Bronchus-associated lymphoid tissue (BALT) participates in airway immune responses. However, little is known about the lymphocyte–endothelial adhesion cascades that recruit lymphocytes from blood into BALT. We show that high endothelial venules (HEVs) in BALT express substantial levels of VCAM-1, in marked contrast to HEVs in other secondary lymphoid tissues. BALT HEVs also express the L-selectin ligand PNAd. Anti–L-selectin, anti-PNAd, and anti–LFA-1 mAbs almost completely block the homing of B and T lymphocytes into BALT, whereas anti–α4 integrin and anti–VCAM-1 mAbs inhibit homing by nearly 40%. α4β7 integrin and MAdCAM-1 are not involved. Importantly, we found that mAbs against α4 integrin and VCAM-1 significantly block the migration of total T cells (80% memory phenotype) but not naive T and B cells to BALT. These results suggest that an adhesion cascade, which includes L-selectin/PNAd, α4β1 integrin/VCAM-1, and LFA-1, targets specific lymphocyte subsets to BALT. This high level of involvement of α4β1 integrin/VCAM-1 is unique among secondary lymphoid tissues, and may help unify lymphocyte migration pathways and immune responses in BALT and other bronchopulmonary tissues.

Adenosine inhibits cytokine release and expression of adhesion molecules by activated human endothelial cells

1996 ◽  
Vol 270 (2) ◽  
pp. C522-C529 ◽  
Author(s):  
M. G. Bouma ◽  
F. A. van den Wildenberg ◽  
W. A. Buurman
Keyword(s):  
Endothelial Cells ◽  
Adhesion Molecules ◽  
Adhesion Molecule ◽  
Vascular Endothelium ◽  
Cell Activation ◽  
Umbilical Vein ◽  
Intercellular Adhesion Molecule ◽  
Cytokine Release ◽  
Adenosine Deaminase Activity ◽  
Anti Inflammatory

Ischemia induces excessive ATP catabolism with subsequent local release of its metabolite adenosine, an autacoid with anti-inflammatory properties. Because activation of the vascular endothelium is critical to the inflammatory host response during ischemia and reperfusion, the effects of adenosine on two major determinants of endothelial cell activation (i.e., the release of proinflammatory cytokines and the expression of adhesion molecules) were studied. Adenosine dose dependently inhibited the release of interleukin (IL)-6 and IL-8 by stimulated human umbilical vein endothelial cells (HUVEC). Expression of E-selectin and vascular cell adhesion molecule 1 (VCAM-1), but not intercellular adhesion molecule 1 (ICAM-1), by activated HUVEC was also reduced by adenosine. Inhibition of endogenous adenosine deaminase activity by erythro-9-(2-hydroxy-3-nonyl)adenine or 2'-deoxycoformycin strongly enhanced the inhibitory effects of exogenous adenosine on cytokine release and expression of E-selectin and VCAM-1. However, a clear role for specific adenosine receptors in the described inhibitory events could not be established. Together, these data imply that the vascular endothelium constitutes an important target for the anti-inflammatory actions of adenosine.

scholarly journals Lipoprotein lipase: cellular origin and functional distribution

1990 ◽  
Vol 258 (4) ◽  
pp. C673-C681 ◽  
Author(s):  
L. Camps ◽  
M. Reina ◽  
M. Llobera ◽  
S. Vilaro ◽  
T. Olivecrona
Keyword(s):  
Endothelial Cells ◽  
Mammary Gland ◽  
Lipoprotein Lipase ◽  
Vascular Endothelium ◽  
Muscle Cells ◽  
Plasma Lipoproteins ◽  
Specific Cell ◽  
Protein Distribution ◽  
Brown Adipose ◽  
Positive Hybridization

Lipoprotein lipase (LPL, E.C. 3.3.1.34) is the enzyme responsible for hydrolysis of triacylglycerols in plasma lipoproteins, making the fatty acids available for use by subjacent tissues. LPL is functional at the surface of endothelial cells, but it is not clear which cells synthesize the enzyme and what its distribution is within tissues and vessels. We have searched for specific cell expression of the LPL gene by in situ hybridization using a RNA probe and for the corresponding protein distribution by immunocytochemistry on cryosections of some LPL-producing tissues of guinea pigs. In white and brown adipose tissues, heart and skeletal muscle, and lactating mammary gland, there was positive hybridization for LPL mRNA over all members of the major cell types, indicating that mature and immature adipocytes, muscle cells, and mammary epithelial cells are main sources of LPL. In large vessels, LPL expression was detected in some smooth muscle cells in the media layer. There was no positive hybridization for LPL mRNA over endothelial cells in any of the tissues studied, but there was immunoreaction for LPL protein at endothelial surfaces of all blood vessels. In the kidney, there was strong immunofluorescence at the vascular endothelium, particularly in the glomeruli, but little or no LPL mRNA was detected in the surrounding cells. These observations suggest that in some tissues LPL is synthesized by parenchymal cells and spreads along the vascular mesh. Transfer to the vascular endothelium is, however, not the only route taken by LPL. In the mammary gland most of the enzyme protein appeared to be secreted, partly in association with milk fat droplets.(ABSTRACT TRUNCATED AT 250 WORDS)

Glutamate induces oxidative stress and apoptosis in cerebral vascular endothelial cells: contributions of HO-1 and HO-2 to cytoprotection

2006 ◽  
Vol 290 (5) ◽  
pp. C1399-C1410 ◽  
Author(s):  
Helena Parfenova ◽  
Shyamali Basuroy ◽  
Sujoy Bhattacharya ◽  
Dilyara Tcheranova ◽  
Yan Qu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Endothelial Cells ◽  
Vascular Endothelium ◽  
Vascular Endothelial Cells ◽  
Glutamate Toxicity ◽  
Vascular Endothelial ◽  
Oxygen Species ◽  
Apoptotic Effects ◽  
Cerebral Vascular

In cerebral circulation, epileptic seizures associated with excessive release of the excitatory neurotransmitter glutamate cause endothelial injury. Heme oxygenase (HO), which metabolizes heme to a vasodilator, carbon monoxide (CO), and antioxidants, biliverdin/bilirubin, is highly expressed in cerebral microvessels as a constitutive isoform, HO-2, whereas the inducible form, HO-1, is not detectable. Using cerebral vascular endothelial cells from newborn pigs and HO-2-knockout mice, we addressed the hypotheses that 1) glutamate induces oxidative stress-related endothelial death by apoptosis, and 2) HO-1 and HO-2 are protective against glutamate cytotoxicity. In cerebral endothelial cells, glutamate (0.1–2.0 mM) increased formation of reactive oxygen species, including superoxide radicals, and induced major keystone events of apoptosis, such as NF-κB nuclear translocation, caspase-3 activation, DNA fragmentation, and cell detachment. Glutamate-induced apoptosis was greatly exacerbated in HO-2 gene-deleted murine cerebrovascular endothelial cells and in porcine cells with pharmacologically inhibited HO-2 activity. Glutamate toxicity was prevented by superoxide dismutase, suggesting apoptotic changes are oxidative stress related. When HO-1 was pharmacologically upregulated by cobalt protoporphyrin, apoptotic effects of glutamate in cerebral endothelial cells were completely prevented. Glutamate-induced reactive oxygen species production and apoptosis were blocked by a CO-releasing compound, CORM-A1 (50 μM), and by bilirubin (1 μM), consistent with the antioxidant and cytoprotective roles of the end products of HO activity. We conclude that both HO-1 and HO-2 have anti-apoptotic effects against oxidative stress-related glutamate toxicity in cerebral vascular endothelium. Although HO-1, when induced, provides powerful protection, HO-2 is an essential endogenous anti-apoptotic factor against glutamate toxicity in the cerebral vascular endothelium.

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