Platelet glycoprotein IIb-IIIa-like proteins mediate endothelial cell attachment to adhesive proteins and the extracellular matrix.

SummaryPurpose: Successful development of a vascular prosthesis lined with endothelial cells (EC) may depend on the ability of the attached cells to resist shear forces after implantation. The present study was designed to investigate EC detachment from extracellular matrix (ECM) precoated vascular prostheses, caused by shear stress in vitro and to test the performance of these grafts in vivo. Methods: Bovine aortic endothelial cells were seeded inside untreated polytetrafluoro-ethylene (PTFE) vascular graft (10 X 0.6 cm), PTFE graft precoated with fibronectin (FN), or PTFE precoated with FN and a naturally produced ECM (106 cells/graft). Sixteen hours after seeding the medium was replaced and unattached cells counted. The strength of endothelial cell attachment was evaluated by subjecting the grafts to a physiologic shear stress of 15 dynes/cm2 for 1 h. The detached cells were collected and quantitated. PTFE or EC preseeded ECM coated grafts were implanted in the common carotid arteries of dogs. Results: While little or no differences were found in the extent of endothelial cell attachment to the various grafts (79%, 87% and 94% of the cells attached to PTFE, FN precoated PTFE, or FN+ECM precoated PTFE, respectively), the number of cells retained after a shear stress was significanly increased on ECM coated PTFE (20%, 54% and 85% on PTFE, FN coated PTFE, and FN+ECM coated PTFE, respectively, p <0.01). Implantation experiments in dogs revealed a significant increase in EC coverage and a reduced incidence of thrombus formation on ECM coated grafts that were seeded with autologous saphenous vein endothelial cells prior to implantation. Conclusion: ECM coating significantly increased the strength of endothelial cell attachment to vascular prostheses subjected to shear stress. The presence of adhesive macromolecules and potent endothelial cell growth promoting factors may render the ECM a promising substrate for vascular prostheses.

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PLATELET GLYCOPROTEIN IIb-IIIa-LIKE PROTEINS MEDIATE ENDOTHELIAL CELL ATTACHMENT TO ADHESIVE MATRIX PROTEINS AND ARE UP-REGULATED BY PHORBOL ESTERS

10.1055/s-0038-1642816 ◽

1987 ◽

Cited By ~ 1

Author(s):

I F Charo ◽

L A Fitzgerald ◽

D Meyer ◽

L S Bekeart ◽

D R Phillips

Keyword(s):

Monoclonal Antibody ◽

Extracellular Matrix ◽

Endothelial Cells ◽

Endothelial Cell ◽

Phorbol Esters ◽

Matrix Proteins ◽

Platelet Glycoprotein ◽

Mrna Levels ◽

Platelet Receptor ◽

Adhesive Proteins

Human endothelial cells (EC) express glycoproteins that are similar to the platelet glycoprotein IIb-IIIa complex (GP IIb-IIIa), the platelet receptor for adhesive proteins. Although GP IIb—IIIa is abundant in both platelets and EC, its only known function is to mediate platelet aggregation. The present study tests the hypotheses that EC attachment to adhesive proteins in the extracellular matrix is mediated by the GP IIb-IIIa-1ike proteins. Endothelial cells attached well to glass slides that were previously coated with adhesive proteins, but not albumin. To determine whether GP IIb-IIIa was involved, EC adherence was measured in the presence and absence of a GP IIb-IIIa monoclonal antibody (7E3) which inhibits fibrinogen (Fg) binding to platelets. The attachment of EC to Fg and von Willebrand factor (vWf), but not fibronectin (Fn) coated slides, was completely inhibited by 7E3. Attachment to vitronectin was partially inhibited. In contrast, EC attachment to Fn was specifically inhibited by a Fn-receptor antibody. Endothelial cell adherence to vWf was also inhibited by a monoclonal antibody (Mab9) against the GP IIb-IIIa binding domain of vWf, but not by antibodies agains.t other portions of vWf. We have further found that 7E3 disrupts monolayers of endothelial cells by detaching the cells from their extracellular matrix. EC incubated in phorbol myris-tate.acetate (PMA) increase in size and appear more tightly adherent to their extracellular matrix. To determine if PMA increases synthesis of cellular receptors for matrix proteins, we have used cDNA probes to measure the mRNA levels of the large subunit of the Fn-receptor (FnRα) and GP IIIa in EC. After a 4 hour incubation in the presence of PMA (10 nM), there was a 2-fold increase in the mRNA levels of both FnRα and GP IIIa, as well as increased cell spreading on the matrix. We conclude: i) the GP Ilb-IIIa complex in EC is a surface receptor for specific adhesive proteins, and is distinct from the FnR, and ii) both GP IIIa and FnRα synthesis are increased by PMA, which causes a concomittant change in cell morphology.

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Hypoxia Induced Heparan Sulfate Primes the Extracellular Matrix for Endothelial Cell Recruitment by Facilitating VEGF-Fibronectin Interactions

International Journal of Molecular Sciences ◽

10.3390/ijms20205065 ◽

2019 ◽

Vol 20 (20) ◽

pp. 5065 ◽

Cited By ~ 3

Author(s):

Jo Ann Buczek-Thomas ◽

Celeste B. Rich ◽

Matthew A. Nugent

Keyword(s):

Extracellular Matrix ◽

Endothelial Cell ◽

Cell Attachment ◽

Retinal Cell ◽

Growth And Survival ◽

Cell Recruitment ◽

Rpe Cells ◽

Binding Forms ◽

Endothelial Cell Attachment ◽

Endothelial Cell Recruitment

Vascular endothelial growth factor-A (VEGF) is critical for the development, growth, and survival of blood vessels. Retinal pigmented epithelial (RPE) cells are a major source of VEGF in the retina, with evidence that the extracellular matrix (ECM)-binding forms are particularly important. VEGF associates with fibronectin in the ECM to mediate distinct signals in endothelial cells that are required for full angiogenic activity. Hypoxia stimulates VEGF expression and angiogenesis; however, little is known about whether hypoxia also affects VEGF deposition within the ECM. Therefore, we investigated the role of hypoxia in modulating VEGF-ECM interactions using a primary retinal cell culture model. We found that retinal endothelial cell attachment to RPE cell layers was enhanced in cells maintained under hypoxic conditions. Furthermore, we found that agents that disrupt VEGF-fibronectin interactions inhibited endothelial cell attachment to RPE cells. We also found that hypoxia induced a general change in the chemical structure of the HS produced by the RPE cells, which correlated to changes in the deposition of VEGF in the ECM, and we further identified preferential binding of VEGFR2 over VEGFR1 to VEGF laden-fibronectin matrices. Collectively, these results indicate that hypoxia-induced HS may prime fibronectin for VEGF deposition and endothelial cell recruitment by promoting VEGF-VEGFR2 interactions as a potential means to control angiogenesis in the retina and other tissues.

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Glycoprotein Ib Can Mediate Endothelial Cell Attachment to a von Willebrand Factor Substratum

Thrombosis and Haemostasis ◽

10.1055/s-0038-1653770 ◽

1995 ◽

Vol 73 (02) ◽

pp. 309-317 ◽

Cited By ~ 16

Author(s):

Dorothy A Beacham ◽

Miguel A Cruz ◽

Robert I Handin

Keyword(s):

Endothelial Cell ◽

Von Willebrand Factor ◽

Cell Attachment ◽

Umbilical Vein ◽

Single Amino Acid ◽

Cell Surface Expression ◽

Platelet Glycoprotein ◽

Glycoprotein Ib ◽

Von Willebrand ◽

Willebrand Factor

SummaryIntroduction of single amino acid substitutions into the C-terminal Arg-Gly-Asp-Ser (RGDS) site of von Willebrand Factor, referred to as RGD mutant vWF, selectively abrogated vWF binding to platelet glycoprotein IIb/IIIa (GpIIb/IIIa, αIIbβ3 and abolished human umbilical vein endothelial cell (HUVEC) spreading, but not attachment, to RGD mutant vWF (Beacham, D. A., Wise, R. J., Turci, S. M. and Handin, R. I. 1992. J. Biol. Chem. 167, 3409-3415). These results suggested that in addition to the vitronectin receptor (VNR, αvβ3), a second endothelial membrane glycoprotein can mediate HUVEC adhesion to vWF. HUVEC attachment to wild-type (WT) and RGD-mutant vWF was reduced by two proteins known to block the vWF-platelet glycoprotein Ib/IX (GpIb/IX) interaction, the monoclonal antibody AS-7 and the recombinant polypeptide, vWF-A1. The addition of cytochalasin B or DNase I to disrupt potential GPIbα-cytoskeletal interactions enhanced the immunoprecipitation of endothelial GPIbα, caused HUVEC to round up, and increased HUVEC adhesion to RGD mutant vWF. These results indicate that while the VNR is the primary adhesion receptor for vWF, endothelial GPIbα can mediate HUVEC attachment to vWF. GpIb-dependent attachment could contribute to HUVEC adhesion under conditions when cell surface expression of the VNR is downregulated, and VNR-dependent adhesion is reduced.

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Shape Memory Polymers Containing Higher Acrylate Content Display Increased Endothelial Cell Attachment

Polymers ◽

10.3390/polym9110572 ◽

2017 ◽

Vol 9 (11) ◽

pp. 572 ◽

Cited By ~ 4

Author(s):

Tina Govindarajan ◽

Robin Shandas

Keyword(s):

Endothelial Cell ◽

Shape Memory ◽

Cell Attachment ◽

Shape Memory Polymers ◽

Endothelial Cell Attachment

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Serum enhancement of human endothelial cell attachment to and spreading on collagens I and IV does not require serum fibronectin or vitronectin

Journal of Cell Science ◽

10.1242/jcs.95.2.255 ◽

1990 ◽

Vol 95 (2) ◽

pp. 255-262

Author(s):

W.D. Norris ◽

J.G. Steele ◽

G. Johnson ◽

P.A. Underwood

Keyword(s):

Endothelial Cell ◽

Culture Medium ◽

Type I Collagen ◽

Cell Attachment ◽

Cell Spreading ◽

Human Endothelial Cell ◽

Collagen Type Iv ◽

Type I ◽

Type Iv ◽

Endothelial Cell Attachment

The initial attachment and spreading of endothelial cells from human umbilical artery onto type I collagen, type IV collagen or gelatin substrata was shown to be enhanced by inclusion of serum in the culture medium. To test whether this serum effect was mediated by adsorption of serum fibronectin or vitronectin onto the collagen, these adhesive glycoproteins were selectively removed from the serum prior to addition to the culture medium. The stimulatory effect of serum on human endothelial cell spreading on collagens I and IV was also observed with serum from which either fibronectin or vitronectin, or both, had been selectively removed. The stimulatory effect for cell spreading on gelatin was diminished by selective removal of serum fibronectin, but unaffected by removal of vitronectin. Human endothelial cell attachment and spreading onto tissue culture plastic was abolished by removal of vitronectin from the serum in the culture medium. These results emphasize that the native structure of collagens is required for serum-enhancement of human endothelial cell attachment and spreading on native collagen types I and IV, and show that on these substrata the stimulated adhesion and spreading are not dependent upon adsorption of serum fibronectin or vitronectin onto the collagen substratum.

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