Leukocyte Adhesion Molecules Research Articles

Early Life Adversity and Inflammation in African Americans and Whites in the Midlife in the United States Survey

To determine whether early life adversity (ELA) was predictive of inflammatory markers and to determine the consistency of these associations across racial groups. We analyzed data from 177 African Americans and 822 whites aged 35 to 86 years from two preliminary subsamples of the Midlife in the United States biomarker study. ELA was measured via retrospective self-report. We used multivariate linear regression models to examine the associations between ELA and C-reactive protein, interleukin-6, fibrinogen, endothelial leukocyte adhesion molecule-1, and soluble intercellular adhesion molecule-1, independent of age, gender, and medications. We extended race-stratified models to test three potential mechanisms for the observed associations. Significant interactions between ELA and race were observed for all five biomarkers. Models stratified by race revealed that ELA predicted higher levels of log interleukin-6, fibrinogen, endothelial leukocyte adhesion molecule-1, and soluble intercellular adhesion molecule-1 among African Americans (p < .05), but not among whites. Some, but not all, of these associations were attenuated after adjustment for health behaviors and body mass index, adult stressors, and depressive symptoms. ELA was predictive of high concentrations of inflammatory markers at midlife for African Americans, but not whites. This pattern may be explained by an accelerated course of age-related disease development for African Americans.

615 TGF-beta regulation of the inflammatory tumour microenvironment

To provide a more complete picture of the effect of interleukin-1 beta (IL-1β) on adult human articular chondrocyte gene expression, in contrast to the candidate gene approach.Chondrocytes from human knee cartilage were cultured in medium containing IL-1β. Changes in gene expression were analyzed by microarray and reverse transcriptase-polymerase chain reaction analysis. The ability of transforming growth factor beta-1 (TGF-β1), fibroblast growth factor (FGF)-18, and bone morphogenetic protein 2 (BMP-2) to alter the effects of IL-1β was analyzed. Computational analysis of the promoter regions of differentially expressed genes for transcription factor binding motifs was performed.IL-1β-treated human chondrocytes showed significant increases in the expression of granulocyte colony stimulating factor-3, endothelial leukocyte adhesion molecule 1 and leukemia inhibitory factor as well as for a large group of chemokines that include CXCL1, CXCL2, CXCL3, CXCL5, CXCL6, CXCL8, CCL2, CCL3, CCL4, CCL5, CCL8, CCL20, CCL3L1, CX3CL1 and the cytokine IL-6. As expected, the mRNA for matrix metalloproteinase (MMP)-13 and BMP-2 also increased while mRNA for the matrix genes COL2A1 and aggrecan was down-regulated. A subset of chemokines increased rapidly at very low levels of IL-1β. The phenotype induced by IL-1β was partially reversed by TGF-β1, but not by BMP-2. In the presence of IL-1β, FGF-18 increased expression of ADAMTS-4, aggrecan, BMP-2, COL2A1, CCL3, CCL4, CCL20, CXCL1, CXCL3, CXCL6, IL-1β, IL-6, and IL-8 and decreased ADAMTS-5, MMP-13, CCL2, and CCL8. Computational analysis revealed a high likelihood that the most up-regulated chemokines are regulated by the transcription factors myocyte enhancer binding factor-3 (MEF-3), CCAAT/enhancer binding protein (C/EBP) and nuclear factor-kappa B (NF-κB).IL-1β has a diverse effect on gene expression profile in human chondrocytes affecting matrix genes as well as chemokines and cytokines. TGF-β1 has the ability to antagonize some of the phenotype induced by IL-1β.

Gardenia jasminoides inhibits tumor necrosis factor‐alpha‐induced vascular inflammation in endothelial cells

Inflammatory mediators such as tumor necrosis factor-alpha (TNF-alpha) enhance binding of low-density lipoprotein to endothelium and upregulate the expression of endothelial leukocyte adhesion molecules during atherogenesis. The present study examined the effect of ethanol extract of Gardenia jasminoides (EGJ) on vascular inflammation in primary cultured human umbilical vein endothelial cells (HUVEC). TNF-alpha-induced the expression of vascular cell adhesion molecule-1 (VCAM-1) and endothelial cell-selectin (E-selectin) expression was inhibited in HUVEC pretreated with EGJ. In a functional study, EGJ dose-dependently attenuated adhesion of HL-60 monocytes to endothelial monolayers. A further analysis indicated that EGJ attenuated TNF-alpha-induced nuclear p65 nuclear factor-kappa B (NF-kappaB) translocation, suggesting that EGJ primarily affects the TNF-alpha-induced NF-kappaB signaling pathway. Taken together, we provided here the first evidence showing that EGJ is able to inhibit TNF-alpha-induced NF-kappaB activation, adhesion molecule expression, and monocyte-endothelial interaction, suggesting an anti-inflammatory role of EGJ, which may be useful in preventing vascular diseases, such as atherosclerosis.

Diabetic macular oedema: physical, physiological and molecular factors contribute to this pathological process

Diabetic macular oedema (DMO) is an important cause of vision loss in patients with diabetes mellitus. The underlying mechanisms of DMO, on both macrocellular and microcellular levels, are discussed in this review. The pathophysiology of DMO can be described as a process whereby hyperglycaemia leads to overlapping and inter-related pathways that play a role not only in the initial vascular events, but also in the continued tissue insult that leads to chronic DMO. On a macrocellular level, DMO is believed to be in part caused by alterations in hydrostatic pressure, oxygen tension, oncotic pressure and shear stress. Three key components of the microvascular pathways include angiogenic factor expression, inflammation and oxidative stress. These molecular mediators, acting in conjunction with macrocellular factors, which are all stimulated in part by the hyperglycaemia and hypoxia, can have a direct endothelial effect leading to hyperpermeability, disruption of vascular endothelial cell junctions, and leukostasis. The interactions, signalling events and feedback loops between the various molecules are complicated and are not completely understood. However, by attempting to understand the pathways involved in DMO, we can help guide new treatment options targeted towards specific factors or mediators.

NAD(P)H:quinone oxidoreductase 1-compromised human bone marrow endothelial cells exhibit decreased adhesion molecule expression and CD34+ hematopoietic cell adhesion.

NAD(P)H:quinone oxidoreductase 1 (NQO1) deficiency resulting from a homozygous NQO1*2 polymorphism has been associated with an increased risk of benzene-induced myeloid toxicity and a variety of de novo and therapy-induced leukemias. Endothelial cells in human bone marrow form one of the two known hematopoietic stem cell microenvironments and are one of the major cell types that express NQO1 in bone marrow. We have used a transformed human bone marrow endothelial cell (TrHBMEC) line to study the potential impact of a lack of NQO1 activity on adhesion molecule [endothelial leukocyte adhesion molecule 1 (E-selectin), vascular cell adhesion molecule (VCAM)-1, and intercellular adhesion molecule (ICAM)-1] expression and functional adhesion to bone marrow progenitor cells. We used both 5-methoxy-1,2-dimethyl-3-[(4-nitrophenoxy)methyl]indole-4,7-dione (ES936), a mechanism-based inhibitor of NQO1, and anti-NQO1 small interfering RNA to abrogate NQO1 activity. Real-time reverse transcription-polymerase chain reaction data demonstrated a significant inhibition of tumor necrosis factor (TNF)alpha-induced E-selectin mRNA levels after ES936 pretreatment. Immunoblot assays demonstrated a significant reduction in TNFalpha-stimulated E-selectin, VCAM-1, and ICAM-1 proteins after inhibition or knockdown of NQO1. The mechanisms underlying this effect remain undefined, but modulation of nuclear factor-kappaB (p65), c-Jun, and activating transcription factor 2, transcriptional regulators of adhesion molecules, were observed after inhibition or knockdown of NQO1. Decreased level of E-selectin, VCAM-1, and ICAM-1 also resulted in a functional deficit in adhesion. A parallel plate flow chamber study demonstrated a marked reduction in CD34(+) cell (KG1a) adhesion to NQO1-deficient TrHBMECs relative to controls. The reduced adhesive ability of TrHBMECs may affect the function of the vascular stem cell niche and also may contribute to the increased susceptibility of polymorphic individuals lacking NQO1 to leukemias and hematotoxicants such as benzene.

Low anticoagulant heparin targets multiple sites of inflammation, suppresses heparin-induced thrombocytopenia, and inhibits interaction of RAGE with its ligands

While heparin has been used almost exclusively as a blood anticoagulant, important literature demonstrates that it also has broad anti-inflammatory activity. Herein, using low anti-coagulant 2-O,3-O-desulfated heparin (ODSH), we demonstrate that most of the anti-inflammatory pharmacology of heparin is unrelated to anticoagulant activity. ODSH has low affinity for anti-thrombin III, low anti-Xa, and anti-IIa anticoagulant activities and does not activate Hageman factor (factor XII). Unlike heparin, ODSH does not interact with heparin-platelet factor-4 antibodies present in patients with heparin-induced thrombocytopenia and even suppresses platelet activation in the presence of activating concentrations of heparin. Like heparin, ODSH inhibits complement activation, binding to the leukocyte adhesion molecule P-selectin, and the leukocyte cationic granular proteins azurocidin, human leukocyte elastase, and cathepsin G. In addition, ODSH and heparin disrupt Mac-1 (CD11b/CD18)-mediated leukocyte adhesion to the receptor for advanced glycation end products (RAGE) and inhibit ligation of RAGE by its many proinflammatory ligands, including the advanced glycation end-product carboxymethyl lysine-bovine serum albumin, the nuclear protein high mobility group box protein-1 (HMGB-1), and S100 calgranulins. In mice, ODSH is more effective than heparin in reducing selectin-mediated lung metastasis from melanoma and inhibits RAGE-mediated airway inflammation from intratracheal HMGB-1. In humans, 50% inhibitory concentrations of ODSH for these anti-inflammatory activities can be achieved in the blood without anticoagulation. These results demonstrate that the anticoagulant activity of heparin is distinct from its anti-inflammatory actions and indicate that 2-O and 3-O sulfate groups can be removed to reduce anticoagulant activity of heparin without impairing its anti-inflammatory pharmacology.

Estrogen is a modulator of Tumor Necrosis Factor responses in the human vascular endothelium

Premenopausal women are protected against cardiovascular diseases compared to age‐matched men. However, these women are also at an increased risk of inflammatory and autoimmune diseases. Higher circulating levels of estrogen may exert an immunomodulatory effect. Given this background, we hypothesized that chronic estrogen exposure alters the endothelial response to inflammatory stimulation. We treated confluent monolayers of second passage human umbilical vein endothelial cells (HUVECs) for 24 hours with physiologically relevant doses of 17‐beta estradiol (E2) prior to stimulation with the pro‐inflammatory cytokine tumor necrosis factor (TNF). We found that E2 treatment increased TNFR2 levels without affecting TNFR1. There was a trend towards aggravation of TNF induced upregulation of leukocyte adhesion molecules such as intercellular adhesion molecule‐1 (ICAM‐1) and vascular cell adhesion molecule‐1 (VCAM‐1) on E2 pre‐treatment. There was also a change in the activation profile of nuclear factor kappa B on TNF stimulation between E2 treated and control cells. In summary, chronic E2 treatment altered the endothelial responses to TNF stimulation, involving modulation at the levels of receptors, transcriptional pathways and adhesion molecule expression. This work provides a better understanding of the interplay between estrogen and the endothelial inflammatory response in health and disease.

The role of endothelial function and its assessment in rheumatoid arthritis

Patients with rheumatoid arthritis (RA) have a reduced life expectancy when compared with the general population, largely attributable to cardiovascular disease. Factors that contribute to this increased cardiovascular risk include traditional risk factors, which account for only part of the excess, along with manifestations of the disease itself. RA is characterized by inflammation, which also is a key component in the development of atherosclerosis. Inflammation leads to the activation of endothelial cells, which, through an increase in the expression of leukocyte adhesion molecules, promotes a pro-atherosclerotic environment. Endothelial dysfunction is an early preclinical marker of atherosclerosis, and is commonly found in patients with RA. Several methods are available for the assessment of endothelial function, such as flow-mediated dilatation and laser Doppler flowmetry combined with iontophoresis, each with its own advantages and limitations. Studies have shown that endothelial dysfunction in RA is closely associated with inflammation, and therapeutic reduction of inflammation leads to improvements in endothelial function. As such, assessments of endothelial function could prove to be useful tools in the identification and monitoring of cardiovascular risk in patients with RA. Given the increase in cardiovascular mortality associated with RA, effective management must involve prevention of cardiovascular risk, in addition to control of disease activity and inflammation.

Steroid-Resistant Lymphatic Remodeling in Chronically Inflamed Mouse Airways

Angiogenesis and lymphangiogenesis participate in many inflammatory diseases, and their reversal is thought to be beneficial. However, the extent of reversibility of vessel remodeling is poorly understood. We exploited the potent anti-inflammatory effects of the corticosteroid dexamethasone to test the preventability and reversibility of vessel remodeling in Mycoplasma pulmonis-infected mice using immunohistochemistry and quantitative RT-PCR. In this model robust immune responses drive rapid and sustained changes in blood vessels and lymphatics. In infected mice not treated with dexamethasone, capillaries enlarged into venules expressing leukocyte adhesion molecules, sprouting angiogenesis and lymphangiogenesis occurred, and the inflammatory cytokines tumor necrosis factor and interleukin-1 increased. Concurrent dexamethasone treatment largely prevented the remodeling of blood vessels and lymphatics. Dexamethasone also significantly reduced cytokine expression, bacterial burden, and leukocyte influx into airways and lungs over 4 weeks of infection. In contrast, when infection was allowed to proceed untreated for 2 weeks and then was treated with dexamethasone for 4 weeks, most blood vessel changes reversed but lymphangiogenesis did not, suggesting that different survival mechanisms apply. Furthermore, dexamethasone significantly reduced the bacterial burden and influx of lymphocytes but not of neutrophils or macrophages or cytokine expression. These findings show that lymphatic remodeling is more resistant than blood vessel remodeling to corticosteroid-induced reversal. We suggest that lymphatic remodeling that persists after the initial inflammatory response has resolved may influence subsequent inflammatory episodes in clinical situations.

Oxidative Stress and Vascular Smooth Muscle Cell Growth: A Mechanistic Linkage by Cyclophilin A

Inflammation and oxidative stress contribute to the pathology of many diseases, but specific therapeutic targets remain elusive. Oxidative stress, generated by excessive reactive oxygen species (ROS), promotes cardiovascular disease. However, the precise mechanism of how ROS deteriorate vascular function and promote vascular remodeling in vivo has not been clearly elucidated. Cyclophilin A (CyPA) is a 20 kD chaperone protein that is secreted from vascular smooth muscle cells (VSMC) in response to ROS, and stimulates VSMC proliferation and inflammatory cell migration in vitro and in vivo. CyPA (both intracellular and extracellular) contributes to inflammation and atherosclerosis by promoting endothelial cell (EC) apoptosis and EC expression of leukocyte adhesion molecules, stimulating leukocyte migration, enhancing T helper cell type 1 (Th1) responses, increasing proliferation of macrophages and vascular smooth muscle cells (VSMC), and increasing pro-inflammatory signal transduction in VSMC. We tested the hypothesis that CyPA contributes to cardiovascular diseases by analyzing several genetic interventions that include the CyPA knockout mouse and the CyPA overexpressing transgenic mouse (VSMC-Tg). CyPA plays a crucial role in VSMC proliferation/migration and inflammatory cell recruitment, resulting in cardiovascular diseases in vivo.

Ibudilast Inhibits Cerebral Aneurysms by Down-Regulating Inflammation-Related Molecules in the Vascular Wall of Rats

Phosphodiesterase-4 (PDE-4) is a cyclic adenosine monophosphate-specific enzyme involved in various inflammatory diseases. We studied its role in and the effect of ibudilast, which predominantly blocks PDE-4, on rat cerebral aneurysms. Cerebral aneurysms were induced at the anterior cerebral artery-olfactory artery bifurcation of female rats subjected to hypertension, increased hemodynamic stress, and estrogen deficiency. The effect of ibudilast (30 or 60 mg/kg/d for 3 months) on their cerebral aneurysms was studied by morphological and immunohistochemical assessment and quantitative real-time polymerase chain reaction assay. In our in vitro study, we grew endothelial cells stimulated by angiotensin II under estrogen-free conditions and examined the effect of ibudilast on PDE-4 activation and the cyclic adenosine monophosphate level. Morphological evaluation using vascular corrosion casts showed ibudilast significantly suppressed cerebral aneurysms in a dose-dependent manner. In rats with induced cerebral aneurysms, the gene and protein expression of PDE-4 was high, and endothelial leukocyte adhesion molecules (P-selectin, intracellular adhesion molecule 1, and vascular adhesion molecule 1), matrix metalloproteinase-9, and tumor necrosis alpha were expressed. Macrophage migration was also increased. Treatment with ibudilast down-regulated these molecules, suppressed macrophage migration into the aneurysm wall, and inhibited PDE-4 activation and the elevation of cyclic adenosine monophosphate in endothelial cells. These results suggest that blocking of PDE4 is associated with the reduction of inflammation-related molecules and macrophage migration, thereby reducing the progression of cerebral aneurysms. It may represent a new conservative therapy to treat patients with cerebral aneurysms.

Association between homocysteine and endothelial dysfunction markers in stroke disease

Background: Evidence shows that there is an increase in concentrations of markers of endothelial dysfunction immediately following acute ischaemic stroke. Several studies suggest that endothelial dysfunction may be partly caused by oxidation related to the effects of raised total plasma homocysteine.Objective: The aim of this study was to measure changes in total plasma homocysteine and markers of endothelial dysfunction in stroke disease within a known period of time post infarct.Subjects and methods: We studied 40 acute ischaemic stroke patients (mean age ± SD, 50.2 ± 9.5 years) and 42 hospitalised non-stroke patients (mean age, 44.3 ± 14.9 years). Fasting venous blood was obtained within 24 h, 3 days and 7 days after the stroke onset and hospitalisation for non-stroke patients for measurements of total plasma homocysteine, markers of endothelial dysfunction including intracellular adhesion molecule (i-CAM), vascular cell adhesion molecule-1 (v-CAM) and leukocyte adhesion molecule-1 (E-selectin) and C-reactive proteins (CRPs).Results: We found no significant differences in baseline total plasma homocysteine, E-selectin, v-CAM, vitamin B12, and folate concentrations between ischaemic stroke patients and non-stroke controls. i-CAM concentrations were significantly higher and CRPs non-significantly lower at baseline in stroke patients compared with controls. Although all endothelial dysfunction markers increased significantly during the study period, the rise in E-selectin levels was less than that seen in i-CAM, and v-CAM. Total plasma homocysteine concentrations showed positive correlations with creatinine (r = 0.537; P < 0.02), and inverse correlations with both vitamin B12 (r = –0.560; P < 0.001) and folate (r = –0.469; P < 0.002); however, there were no significant correlations between total plasma homocysteine or B-vitamins and markers of endothelial dysfunction in ischaemic stroke patients or controls.Conclusions: We found evidence of an increase in markers of endothelial dysfunction following acute ischaemic stroke but this had no relationship with total plasma homocysteine concentrations.

Endothelial activation with prothrombotic response in irradiated microvascular recipient veins

Surgical wounds within previously irradiated tissues are common in reconstructive surgery and subject to an increased incidence of postoperative complications due to vascular dysfunction, including thrombosis in both microvascular anastomosis and the microcirculatory bed. However, there is no study that has described gene expression patterns in radiated human blood vessels. This study aims to determine if radiation can induce changes in gene expression that can promote thrombus formation in human microvascular recipient veins. Paired biopsies from radiated recipient veins and non-radiated flap veins were simultaneously harvested from 15 patients during free-flap reconstruction, 4-215 weeks from termination of radiation. Radiated and non-radiated veins were compared using a custom-made Taqman(®) low-density array (TLDA) to analyse differential gene expression in a large number of genes involved in inflammation and coagulation. Results were confirmed by real-time polymerase chain reaction (RT-PCR) and immunohistochemistry. Results from TLDA indicate an acute increase of cytokines and leucocyte adhesion molecules related to activation of transcription factor nuclear factor kappa-B (NF-kB), confined to the first 3 months after radiotherapy treatment. Results were confirmed by RT-PCR and activity localised to the endothelium by immunohistochemistry. RT-PCR analyses of genes associated with coagulation showed sustained expression of plasminogen activator inhibitor-1 (PAI-1) in radiated veins. We found an acute inflammatory response with endothelial activation, followed by a sustained PAI-1 gene expression in irradiated microvascular recipient veins that can explain adverse effects years after radiation, such as microvascular occlusion and poor surgical wound healing. We believe that the results contribute to the search for therapeutic adjuncts to cope with the adverse effects of radiation therapy and strongly advocate postoperative, rather than preoperative, radiotherapy whenever possible.

Association of the 98T ELAM-1 Polymorphism With Increased Bleeding After Cardiac Surgery

Hemorrhage continues to be a major problem after cardiac surgery despite the routine use of antifibrinolytic drugs, with striking inter-patient variability poorly explained by already known risk factors. The authors tested the hypothesis that genetic polymorphisms of inflammatory mediators and cellular adhesion molecules are associated with bleeding after cardiac surgery. Prospective, observational study. Single, tertiary referral university heart center. Adult patients undergoing aortocoronary surgery with cardiopulmonary bypass. Patients (n = 759) had 10 mL of blood drawn preoperatively and genomic DNA isolated then genotyped for 17 polymorphisms in 7 candidate genes: tumor necrosis factor, interleukins 1beta and 6, interleukin 1 receptor antagonist, intercellular adhesion molecule-1 (ICAM-1), P-selectin and endothelial leucocyte adhesion molecule-1 (E-selectin). Multivariate analyses were used to relate clinical and genetic factors to bleeding and transfusion. The 98G/T polymorphism of the E-selectin gene was independently associated with bleeding after cardiac surgery (p = 0.002), after adjusting for significant clinical predictors (patient size and baseline hemoglobin concentration). There was a gene dose effect according to the number of minor alleles in the genotype; carriers of the minor allele bled 17% (GT) and 54% (TT) more than wild type (GG) genotypes, respectively (p = 0.01). Carriers of the minor allele also had longer activated partial thromboplastin times (p = 0.0023) and increased fresh frozen plasma transfusion (p = 0.03) compared with wild type. The authors found a dose-related association between the 98T E-selectin polymorphism and bleeding after cardiac surgery, independent of and additive to standard clinical risk factors.

Prehospital resuscitation with hypertonic saline-dextran modulates inflammatory, coagulation and endothelial activation marker profiles in severe traumatic brain injured patients

BackgroundTraumatic brain injury (TBI) initiates interrelated inflammatory and coagulation cascades characterized by wide-spread cellular activation, induction of leukocyte and endothelial cell adhesion molecules and release of soluble pro/antiinflammatory cytokines and thrombotic mediators. Resuscitative care is focused on optimizing cerebral perfusion and reducing secondary injury processes. Hypertonic saline is an effective osmotherapeutic agent for the treatment of intracranial hypertension and has immunomodulatory properties that may confer neuroprotection. This study examined the impact of hypertonic fluids on inflammatory/coagulation cascades in isolated head injury.MethodsUsing a prospective, randomized controlled trial we investigated the impact of prehospital resuscitation of severe TBI (GCS < 8) patients using 7.5% hypertonic saline in combination with 6% dextran-70 (HSD) vs 0.9% normal saline (NS), on selected cellular and soluble inflammatory/coagulation markers. Serial blood samples were drawn from 65 patients (30 HSD, 35 NS) at the time of hospital admission and at 12, 24, and 48-h post-resuscitation. Flow cytometry was used to analyze leukocyte cell-surface adhesion (CD62L, CD11b) and degranulation (CD63, CD66b) molecules. Circulating concentrations of soluble (s)L- and sE-selectins (sL-, sE-selectins), vascular and intercellular adhesion molecules (sVCAM-1, sICAM-1), pro/antiinflammatory cytokines [tumor necrosis factor (TNF)-α and interleukin (IL-10)], tissue factor (sTF), thrombomodulin (sTM) and D-dimers (D-D) were assessed by enzyme immunoassay. Twenty-five healthy subjects were studied as a control group.ResultsTBI provoked marked alterations in a majority of the inflammatory/coagulation markers assessed in all patients. Relative to control, NS patients showed up to a 2-fold higher surface expression of CD62L, CD11b and CD66b on polymorphonuclear neutrophils (PMNs) and monocytes that persisted for 48-h. HSD blunted the expression of these cell-surface activation/adhesion molecules at all time-points to levels approaching control values. Admission concentrations of endothelial-derived sVCAM-1 and sE-selectin were generally reduced in HSD patients. Circulating sL-selectin levels were significantly elevated at 12 and 48, but not 24 h post-resuscitation with HSD. TNF-α and IL-10 levels were elevated above control throughout the study period in all patients, but were reduced in HSD patients. Plasma sTF and D-D levels were also significantly lower in HSD patients, whereas sTM levels remained at control levels.ConclusionsThese findings support an important modulatory role of HSD resuscitation in attenuating the upregulation of leukocyte/endothelial cell proinflammatory/prothrombotic mediators, which may help ameliorate secondary brain injury after TBI.Trial registrationNCT00878631.

Chemokine patterning by glycosaminoglycans and interceptors

Chemokines mediate leukocyte emigration from blood into tissues. This process is triggered by chemokines binding and signaling through their cognate G-protein-coupled receptors on leukocytes and requires the involvement of leukocyte and endothelial cell adhesion molecules. Additionally, in vivo chemokine activity depends on their interaction with "auxiliary" molecules expressed by the vascular endothelial cells. Secreted chemokines can be immobilized on the luminal and abluminal endothelial cell surfaces by glycosaminoglycans. In order to be targeted to their presentation sites on the luminal endothelial cell surface, the tissue-derived chemokines have to cross the endothelial cell barrier. For inflammatory chemokines this is accomplished by active transport involving Duffy antigen, an 'interceptor' expressed by venular endothelial cells. Other chemokine interceptors, D6 in particular, may act as scavenging decoys and are involved in clearance of chemokines. The interceptor-mediated transport or elimination of chemokines, together with their immobilization by glycosaminoglycans, lead to chemokine patterning at the blood-tissue interface and within tissues. The resulting chemokine gradients induce leukocyte emigration from blood and may also be necessary for directed leukocyte migration within tissues.

CD73 represses pro-inflammatory responses in human endothelial cells

BackgroundCD73 is a 5'-ectonucleotidase that produces extracellular adenosine, which then acts on G protein-coupled purigenic receptors to induce cellular responses. CD73 has been reported to regulate expression of pro-inflammatory molecules in mouse endothelium. Our aim is to determine the function of CD73 in human endothelial cells.MethodsWe used RNAi to deplete CD73 levels in human umbilical cord endothelial cells (HUVECs).ResultsCD73 depletion resulted in a strong reduction in adenosine production, indicating that CD73 is the major source of extracellular adenosine in HUVECs. We find that CD73 depletion induces a similar response to pro-inflammatory stimuli such as the cytokine TNF-α. In CD73-depleted cells, surface levels of the leukocyte adhesion molecules ICAM-1, VCAM-1 and E-selectin increase. This correlates with increased translocation of the transcription factor NF-kB to the nucleus, which is known to regulate ICAM-1, VCAM-1 and E-selectin expression in response to TNF-α. Adhesion of monocytic cells to endothelial cells is enhanced. In addition, CD73-depleted cells become elongated, have higher levels of stress fibres and increased endothelial permeability, resembling known responses to TNF-α.ConclusionsThese results indicate that CD73 normally suppresses pro-inflammatory responses in human endothelial cells.

Puerarin Inhibits Adhesion Molecule Expression in TNF-α-Stimulated Human Endothelial Cells via Modulation of the Nuclear Factor ĸB Pathway

Background: The isoflavone puerarin is the most abundant isoflavone-C-glucoside extracted from the root (radix puerariae) of the plant Pueraria lobata and possesses many biological activities. In this report, the ability of puerarin to modulate intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and endothelial leukocyte adhesion molecule 1 (E-selectin), and to induce changes in the nuclear factor ĸB (NF-ĸB) pathway in human umbilical vein endothelial cells (HUVECs) was examined. Methods: The protein and mRNA levels of tumor-necrosis-factor-α (TNF-α)-induced ICAM-1, VCAM-1 and E-selectin were determined in HUVECs. Inhibitor ĸB (I-ĸB) phosphorylation and p65 NF-ĸB expression in HUVECs were also examined. Results: Puerarin inhibited the expression of TNF-α-induced ICAM-1, VCAM-1 and E-selectin proteins and mRNAs in HUVECs. Subsequently, we determined that the inhibition of ICAM-1, VCAM-1 and E-selectin expression was due to a dose-dependent suppression of phosphorylation and degradation of I-ĸB, which resulted in a reduction of p65 NF-ĸB nuclear translocation. Conclusion: These data suggested that the effect of puerarin-mediated inhibition of TNF-α-induced ICAM-1, VCAM-1 and E-selectin expression is attributed to suppressed NF-ĸB activation on the transcriptional level.

Abstract B122: Human monoclonal antibodies to sialyl-Lewis-A with potent CDC and ADCC activity

Abstract The carbohydrate antigen sialyl-Lewis A (sLea) is widely expressed on epithelial tumors of the gastrointestinal tract, on breast cancer cells, and also on small cell lung cancer cells, but is expressed minimally or not at all on normal tissues. sLea serves as a ligand for epithelial leukocyte adhesion molecules and higher expression of sLea was observed in patients with greater node involvement. Since over-expression of sLea appears to be a key event in invasion and metastasis of many tumor cells and tumor cells expressing sLea are highly susceptible to antibody mediated lysis mechanisms, sLea presents an attractive molecular target for tumor therapy in a minimal disease setting. Here we report the discovery and initial characterization of fully human antibodies that were generated from blood lymphocytes from individuals immunized with sLea vaccine at MSKCC. Antibodies were identified by ELISA using sLea-HSA conjugates and binding to the native antigen was verified by FACS analysis on DMS-79 cells. Two antibodies were selected for further studies based on the apparent high affinity, which was estimated by Biacore at 0.14 nM for 5B1 (IgG/λ) and 0.04 nM for 7E3 (IgM/κ). These antibodies did not bind to sialyl-Lewis X, Lewis A and other related carbohydrates. Both antibodies have been expressed as fully functional human recombinant antibodies in CHO cells. Complement dependent cytotoxicity (CDC) against DMS-79 cells was approximately 60% and 70–90% for r5B1 and r7E3, respectively. Moreover, r5B1 antibodies showed approximately 50% ADCC of DMS-79 cells with human NK cells (at 5:1 ratio) and 80–90% ADCC with human peripheral blood mononuclear cells with two different blood donors (at 100:1 ratio). These results are very encouraging and we believe that further studies to scale up and test these antibodies in various tumor challenge models are warranted. Since sLea is widely expressed on human cancers, such antibodies could eventually find utility in approximately half of the new cancer cases occurring each year. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B122.

Left ventricular-assisted myocardial revascularization favorably affects levels of circulating adhesion molecules and lung function

We investigated whether the use of left ventricular-assisted (LVA) technique in beating heart myocardial revascularization would exert less impact on patients adhesion molecules and oxygenation index as compared with conventional cardiopulmonary bypass (CPB). Sixty-six consecutive patients undergoing myocardial revascularization were randomly assigned either to LVA (group A, 34 patients) or CPB (group B, 32 patients). Adhesion molecules and oxygenation indexes were measured at baseline and at various time points postoperatively. Pre-operative clinical and demographic data did not differ between the 2 groups. The 2 groups were also similar with respect to mortality, number of grafts performed, duration of extracorporeal circulation, and need for inotropes. However, postoperatively patients treated with LVA had a reduced levels of adhesion molecules compared with patients treated with CPB, as indicated by a significant difference in endothelial leukocyte adhesion molecule-1 (P = .002), intercellullar adhesion molecule-1 (P = .0001), and vascular cell adhesion molecule-1 (P = .004). The oxygenation index at 1 (P = .04) and 3 hours (P = .03) postoperatively was better in the LVA group than in the CPB group. Patients undergoing beating heart myocardial revascularization with LVA show reduced levels of adhesion molecules and better oxygenation index than patients treated with CPB.