C5b-9 membrane attack complex mediates endothelial cell apoptosis in experimental glomerulonephritis

We studied the role of the C5b-9 membrane attack complex in two models of inflammatory glomerulonephritis (GN) initiated by acute glomerular endothelial injury in Piebold-viral-Glaxo (PVG) complement-sufficient rats (C+), C6-deficient rats (C6−), and rats systematically depleted of complement with cobra venom factor (CVF). GN was induced by performing a left nephrectomy and selectively perfusing the right kidney with either 1) the lectin concanavalin A (Con A) followed by complement-fixing anti-Con A (Con A GN) or 2) purified complement-fixing goat anti-rat glomerular endothelial cell (GEN) antibody [immune-mediated thrombotic microangiopathy (ITM)]. Comparable levels of GEN apoptosis were detected in C+ animals in both models. CVF administration reduced GEN apoptosis by 10- to 12-fold. GEN apoptosis was C5b-9 dependent because PVG C6− rats were protected from GEN loss. Furthermore, functional inhibition of the cell surface complement regulatory protein CD59 by renal perfusion with anti-CD59 antibody in ITM resulted in a 3.5-fold increase in GEN apoptosis. Last, in Con A GN, abrogation of GEN apoptosis preserved endothelial integrity and renal function. This study demonstrates the specific role of C5b-9 in the induction of GEN apoptosis in experimental inflammatory GN, a finding with implications for diseases associated with the presence of antiendothelial cell antibodies.

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PREFERENTIAL RECOGNITION OF VITRONECTIN (S-PR0TEIN) BY A MONOCLONAL ANTIBODY UPON INTERACTION WITH THROMBIN, ANTITHROMBIN AND GLYCOSAMINOGLYCANS

10.1055/s-0038-1643634 ◽

1987 ◽

Author(s):

B R Tomaslni ◽

D F Mosher

Keyword(s):

Monoclonal Antibody ◽

Conformational Change ◽

Membrane Attack Complex ◽

Physiological Role ◽

Keratan Sulfate ◽

Fold Increase ◽

Antigenic Determinants ◽

Preferential Recognition ◽

Relative Potencies

V1tronect1n/S-Prote1n (VN/SP) is a glycoprotein present at a concentration of 200-400 ug/ml 1n plasma and serum. It has been shown to promote cel 1-substratum adhesion and to act as an Inhibitor of the membrane attack complex of complement and of the inactivation of thrombin by antithrombin III in the presence of low levels of heparin. We have previously shown that VN/SP binds more avidly to heparln-agarose and to a monoclonal antibody (MaVN/SP)-Sepharose column when present 1n serum rather than 1n plasma. In order to examine the possibility of a serum-induced conformational change, we utilized, 1n this study, an Indirect enzyme-linked Immunosorbent system to test for the exposure of new antigenic determinants. When MaVN/SP was Incubated with plasma or serum, recognition of VN/SP 1n serum was approximately 50 fold greater than recognition of VN/SP in plasma. Since VN/SP has been shown to Interact strongly with the thromb1n-ant1thrombin complex, we examined the antigenicity of VN/SP when Incubated with thrombin and antithrombin 1n the presence and absence of heparin. Incubation of VN/SP with heparin promoted a 2.5-fold Increase 1n recognition by MaVN/SP. When MaVN/SP was Incubated with thromb1n-ant1thrombin but not thrombin or antithrombin alone, recognition was Increased by 7-fold 1n the absence of heparin and by 32-fold 1n the presence of heparin. This differential recognition of VN/SP was not observed with a second monoclonal antibody raised originally against S-Prote1n. Treatment of VN/SP with various glycosaminoglycans and polysaccharides demonstrated the following relative potencies for Induction of the partial antigenic change: dextran sulfate>fucoidan>heparin> dermatan suIfate>hyaluronic acid. No effect was detected upon Incubation of VN/SP with keratan sulfate, heparan sulfate or chondroltln sulfate. These data suggest a conformational change Induced by thrombin-antlthrombin which may allow VN/SP to Interact more avidly with other molecules such as heparin. The physiological role of this putative conformational change is under investigation.

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Peripheral hypertension and alterations in pulmonary vascular regulation

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1997.273.1.l113 ◽

1997 ◽

Vol 273 (1) ◽

pp. L113-L118

Author(s):

T. Burke-Wolin ◽

P. Pino ◽

M. Itani ◽

M. Talerico ◽

M. Pucci ◽

...

Keyword(s):

Endothelial Cell ◽

Soluble Guanylate Cyclase ◽

Systemic Hypertension ◽

Control Group ◽

Vascular Regulation ◽

Basal Tone ◽

Dependent Model ◽

The Right ◽

Guanylate Cyclase Activation

We have recently reported in normal isolated-perfused rat lungs that low basal tone appears to be regulated by nitric oxide (NO)-dependent and -independent mechanisms of soluble guanylate cyclase activation. In this study, we examined the role of NO in the regulation of pulmonary artery (PA) tone from rats with renin-dependent hypertension. Rats were made hypertensive by ligating the abdominal aorta above the left and below the right renal artery (aortic coarctation, AC). Mean arterial pressure significantly increased from 119 +/- 8.4 mmHg in control animals to 156 +/- 15 mmHg 7-14 days after AC surgery. PA pressures, however, remained unchanged (8.5 +/- 3.4 mmHg in control animals vs. 11 +/- 3.3 mmHg in AC animals). Hypoxic contractions in U-46619 precontracted isolated small PA (160-260 microns diameter) were significantly increased from 51 +/- 13 mg in the control group to 142 +/- 38 mg (P < or = 0.05) in AC animals. Nitro-L-arginine (NLA; 100 microM) contractions were also enhanced in the AC animal. The enhanced NLA response may correlate with an increase in endothelial cell NO synthase (NOS) as detected by Western blotting (132 +/- 28% of control; P < 0.05). These data suggest that, in this renin-dependent model of systemic hypertension, there is increased endothelial cell NOS activity that maintains low PA tone, preventing the lung from developing increased pressures.

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Role of Junction‐Mediating and Regulatory Protein in the Pathogenesis of Glucocorticoid‐Induced Endothelial Cell Lesions

Orthopaedic Surgery ◽

10.1111/os.12680 ◽

2020 ◽

Vol 12 (3) ◽

pp. 964-973

Author(s):

Wei Zuo ◽

Wan‐shou Guo ◽

Hua‐chen Yu ◽

Pei Liu ◽

Qi‐dong Zhang

Keyword(s):

Endothelial Cell ◽

Regulatory Protein

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Thromboxane Modulates Endothelial Permeability

Mediators of Inflammation ◽

10.1155/s0962935194000190 ◽

1994 ◽

Vol 3 (2) ◽

pp. 149-153 ◽

Cited By ~ 8

Author(s):

J. M. Klausner ◽

S. Abu-Abid ◽

J. S. Alexander ◽

R. Hanshke-Mineau ◽

G. Goldman ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Receptor Antagonist ◽

Endothelial Permeability ◽

Fold Increase ◽

Gap Formation ◽

Aortic Endothelial Cells ◽

Bovine Aortic Endothelial Cells

The study tests the role of thromboxane in modulating microvascular permeabilityin vitro. Cultured monolayers of bovine aortic endothelial cells were challenged with the thromboxane (Tx) mimic U46619. This led to disassembly of actin microfilaments, cell rounding, border retraction and interendotheHal gap formation. Pretreatment with the Tx receptor antagonist SQ 29,548 prevented the Tx mimic-induced cytoskeletal changes. The Tx mimic also altered endothelial cell barrier function. Increased permeability was indicated by the increased passage of labelled albumin across monolayers cultured on microcarriers, relative to untreated endothelial cells (p<0.05). Furthermore, electron microscopy of endothelial cells cultured on the basement membrane of human placental amnion indicated increased permeability based on wide, interendotheHal gap formation and transit of the tracer horseradish peroxidase. Quantification of interendothelial gaps revealed an eleven-fold increase with the Tx mimic relative to untreated endothial cells (p<0.05) and prevention by pretreatment with the Tx receptor antagonist (p<0.05). These data indicate that Tx directly modulates the permeability of endothelial cellin vitro.

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CD59 protects glomerular endothelial cells from immune-mediated thrombotic microangiopathy in rats.

Journal of the American Society of Nephrology ◽

10.1681/asn.v94590 ◽

1998 ◽

Vol 9 (4) ◽

pp. 590-597 ◽

Cited By ~ 4

Author(s):

M Nangaku ◽

C E Alpers ◽

J Pippin ◽

S J Shankland ◽

K Kurokawa ◽

...

Keyword(s):

Renal Artery ◽

Thrombotic Microangiopathy ◽

Regulatory Protein ◽

Protective Role ◽

Immune Mediated ◽

Glomerular Endothelium ◽

A Cell ◽

Membrane Bound ◽

Artery Perfusion

CD59 is a cell membrane-bound complement regulatory protein on glomerular cells that inhibits C5b-9 assembly and insertion. This report describes a recently developed model of immune thrombotic microangiopathy (TMA) induced by the renal artery perfusion of anti-glomerular endothelial cell (anti-GEN) antibody. To examine the role of CD59 in protecting the GEN from immune-mediated injury, rats underwent selective renal artery perfusion with F(ab')2 fragments of anti-CD59 monoclonal antibody to block CD59 activity or control mouse IgG followed by anti-GEN antibody or control goat IgG. Neutralization of CD59 in normal rats did not result in any significant functional or histologic changes. Perfusion with anti-CD59 did not change deposition of the pathogenic anti-GEN IgG used to induce the TMA model. However, neutralization of CD59 in the TMA model resulted in more C5b-9 formation in glomeruli, accompanied by increased platelet and fibrin deposition, more severe endothelial injury, and reduced renal function compared with the animals perfused with control F(ab')2 fragments. These results demonstrate directly that CD59 serves a protective role for GEN in this TMA model of rats, and confirm that C5b-9 formation has a critical pathogenic role in the mediation of the disease. CD59 may play an important role in protecting glomerular endothelium from other complement-mediated types of injury.

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