Expression of immunologically relevant endothelial cell activation antigens on isolated central neurvous system microvessels from patients with multiple sclerosis

Activation of the vascular endothelium is thought to be an important facet of inflammation, thrombosis, and vasculitis. Activated endothelial cells express a number of immunologically relevant surface markers not expressed by normal endothelial cells. Many of these surface antigens are thought to augment adhesion reactions and migration. Our results show that endothelial activation may play a centrla role in the pathogenesis of multiple sclerosis (MS). Normal human central nervous system microvessels isolated from autopsy material do not express endothelial cell activation markers, including the adhesion proteins vascular cell adhesion molecule-1 (VCAM-1) and endothelial cell leukocyte adhesion molecule-1 (E-selectin/ELAM-1). They exhibit little to no constitutive expression of immunoreactive intercellular adhesion molecule-1 (ICAM-1) or the urokinase plasminogen activator receptor. Control microvessels exhibit no major histocompatibility complex (MHC) class II antigen. MS microvessels express significant levels of MHC class II antigens, ICAM-1, VCAM-1, and urokinase plasminogen activator receptor. E-selectin was expressed by 3 of 5 MS brains tested. Histologically unaffected areas of MS brain expressed less VCAM-1, ICAM-1, and E-selectin than did microvessels from periplaque zones. However, MHC class II antigens and urokinase plasminogen activator receptor were increased in areas exhibiting little to no evidence of leukocyte infiltration. When microvessels were examined for dual expression of activation markers, we found that in periplaque areas, 50% of microvessels coexpressed HLA-Dr. and VCAM-1, 28% of microvessels coexpressed HLA-Dr. and urokinase plasminogen activator receptor, and 43% of microvessels coexpressed HLA-Dr. and ICAM-1.     

Upregulation of intercellular adhesion molecule-1 expression on human endothelial cells by tumour necrosis factor-alpha in an in vitro model of the blood-brain barrier.

Adhesion molecules on the endothelial surface of the blood-brain barrier (BBB) play an important role in the pathogenesis of many encephalopathies, including multiple sclerosis (MS) and cerebral malaria (CM). The expression of four surface molecules of relevance to MS and CM on the immortalized human umbilical vein endothelial cell line, ECV304, was investigated using immunofluorescence flow cytometry. We found that ECV304 cells express intercellular adhesion molecule-1 (ICAM-1) and low levels of CD36, but not vascular cell adhesion molecule-1 (VCAM-1) or E-selectin. This expression pattern was unaltered on ECV304 cells which were co-cultured with C6 glioma cells; conditions under which the endothelial cells display enhanced barrier formation. Tumour necrosis factor-alpha (TNF-alpha), which is elevated in MS and CM, decreased the integrity of the barrier in co-cultured endothelial cells and upregulated the expression of ICAM-1 nine-fold. The significance of elevated ICAM-1 expression in relation to the binding of parasitised erythrocytes at the BBB in CM is discussed.     

Interferon-beta directly influences monocyte infiltration into the central nervous system

Interferon-beta (IFN-beta) has beneficial effects on the clinical symptoms of multiple sclerosis (MS) patients, but its exact mechanism of action is yet unknown. We here suggest that IFN-beta directly modulates inflammatory events at the level of cerebral endothelium. IFN-beta treatment resulted in a marked reduction of perivascular infiltrates in acute experimental allergic encephalomyelitis (EAE), the rat model for MS, which was coupled to a major decrease in the expression of the adhesion molecules ICAM-1 and VCAM-1 on brain capillaries. In vitro, IFN-beta reduced the mRNA levels and protein expression of adhesion molecules of brain endothelial cell cultures and diminished monocyte transendothelial migration. Monocyte adhesion and subsequent migration was found to be predominantly regulated by VCAM-1. These data indicate that IFN-beta exerts direct antiinflammatory effects on brain endothelial cells thereby contributing to reduced lesion formation as observed in MS patients.     

Circulating,soluble adhesion proteins in cerebrospinal fluid and serum of patients with multiple sclerosis: Correlation with clinical activity

Soluble adhesion protein intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and endothelial leukocyte adhesion molecule (E-selectin) were measured in serum and cerebrospinal fluid (CSF) of patients with relapsing-remitting multiple sclerosis (RRMS) in remission and in exacerbation, as well as patients with chronic progressive MS, stable MS, and in patients with other neurological and inflammatory diseases (ONDs). Serum ICAM-1 and E-selectin were significantly elevated in patients with MS over those with ONDs and controls. CSF VCAM-1 and E-selectin were found to be elevated over control and disease control samples. No increase in CSF ICAM-1 was observed. Results were analyzed longitudinally and by MS category. In paired CSF and serum samples from patients in exacerbation, elevated VCAM-1 correlated with increased serum VCAM-1 in 5 of 7 patients. Elevated CSF E-selectin did not correlate with elevations in serum E-selectin.     

Lipoic acid inhibits expression of ICAM-1 and VCAM-1 by CNS endothelial cells and T cell migration into the spinal cord in experimental autoimmune encephalomyelitis

Lipoic acid (LA) suppresses and treats murine experimental autoimmune encephalomyelitis (EAE), which models multiple sclerosis. However, the mechanisms by which LA mediates its effects in EAE are only partially known. In the present study, LA (25, 50 and 100 microg/ml) inhibited upregulation of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-alpha (TNF-alpha) stimulated cultured brain endothelial cells. Immunohistochemical analysis of spinal cords from SJL mice that had received LA (100 mg/kg/day) following immunization to induce EAE exhibited markedly reduced expression of ICAM-1 and VCAM-1 compared with that of EAE mice receiving saline. Co-localization analysis showed that ICAM-1 and VCAM-1 expression increased over endothelial cells (staining positive for von Willebrand factor, vWF) in EAE and that LA decreased the expression levels to that observed in na?ve mice. Spinal cords from mice receiving LA had significantly reduced inflammation (decreased CD4 and CD11b staining) as compared to EAE mice that received saline. Overall, our data suggest that the anti-inflammatory effects of LA in EAE may be partly due to inhibition of ICAM-1 and VCAM-1 expression by central nervous system (CNS) endothelial cells.     

Upregulation of intercellular adhesion molecule-1 expression on human endothelial cells by tumour necrosis factor-α in an in vitro model of the blood–brain barrier

Adhesion molecules on the endothelial surface of the blood–brain barrier (BBB) play an important role in the pathogenesis of many encephalopathies, including multiple sclerosis (MS) and cerebral malaria (CM). The expression of four surface molecules of relevance to MS and CM on the immortalized human umbilical vein endothelial cell line, ECV304, was investigated using immunofluorescence flow cytometry. We found that ECV304 cells express intercellular adhesion molecule-1 (ICAM-1) and low levels of CD36, but not vascular cell adhesion molecule-1 (VCAM-1) or E-selectin. This expression pattern was unaltered on ECV304 cells which were co-cultured with C6 glioma cells; conditions under which the endothelial cells display enhanced barrier formation. Tumour necrosis factor-α (TNF-α), which is elevated in MS and CM, decreased the integrity of the barrier in co-cultured endothelial cells and upregulated the expression of ICAM-1 nine-fold. The significance of elevated ICAM-1 expression in relation to the binding of parasitised erythrocytes at the BBB in CM is discussed.     

Serum and cerebrospinal fluid levels of soluble adhesion molecules in multiple sclerosis: predominant intrathecal release of vascular cell adhesion molecule-1

Activated cerebral vascular endothelial cells express leukocyte, vascular cell, and intracellular adhesion molecules (E-selectin, VCAM-1 and ICAM-1) which facilitate leukocyte adhesion to endothelium and migration into inflammatory lesions. Paired serum and cerebrospinal fluid (CSF) levels of soluble (s) E-selectin, sVCAM-1 and sICAM-1 were determined by ELISA in patients with clinically definite MS in relapse, and patients with other inflammatory (IND) and non-inflammatory neurological disease (NIND). CSF levels of sVCAM-1 and sICAM-1 were significantly increased in MS patients compared to IND and NIND patients. Elevation of CSF sVCAM-1 in MS patients was the most marked finding (P = 0.0001) and an increased sVCAM-1 index indicated that this was due to intrathecal release of sVCAM-1. There were no differences in serum and CSF sE-selectin levels between the study groups. Measurement of the sVCAM-1 index may provide a marker of disease activity in patients with clinically definite MS.     

Regional and temporal expression patterns of interleukin-10, interleukin-10 receptor and adhesion molecules in the rat spinal cord during chronic relapsing EAE

Adhesion molecules intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) mediate leukocyte infiltration into the CNS, in experimental autoimmune encephalomyelitis (EAE) and multiple sclerosis (MS). Because exogenous interleukin-10 (IL-10) inhibits ICAM-1 and VCAM-1 expression and clinical EAE, we hypothesize that endogenous IL-10 signaling may suppress expression of adhesion molecules. In a rat model of chronic relapsing EAE, expression levels of IL-10 and its receptor (IL-10R1), ICAM-1 and VCAM-1 mRNA in the spinal cord are markedly increased, whereas levels of IL-10 mRNA remain relatively low. The temporal pattern of mRNA and protein expression showed marked differences between spinal cord levels. During relapse, IL-10, IL-10R1, ICAM-1, VCAM-1 mRNA levels and neurological scores show positive correlations. We conclude that endogenous IL-10 is not a crucial factor inhibiting adhesion molecule expression in this model.     

Differential expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in chronic murine retroviral encephalitis

The cell adhesion molecules, intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1, are important mediators of immune interactions within the central nervous system (CNS). A wide variety of pro-inflammatory insults to the brain, including viral infection, result in upregulation of these molecules on brain endothelial cells, astrocytes, and microglia. This study investigated the expression of ICAM-1 and VCAM-1 in chronic encephalitis induced by infection with a temperature sensitive (ts-1) strain of Moloney murine leukaemia virus (MoMuLV), an ecotropic murine retrovirus. During the late stages of disease, viral antigen was present in both endothelial cells and microglia, but not astrocytes, in regions of spongiform change and gliosis. In these areas, ICAM-1 staining was detected on activated microglia, but not on endothelial cells or astrocytes. In contrast, no cells showed increased VCAM-1 expression in the CNS. These findings demonstrate that there is cell-specific, differential expression of these adhesion molecules in ts-1 retroviral encephalitis. The lack of endothelial cell expression correlates with the characteristic lack of lymphocytic infiltrate in this chronic retroviral encephalitis and suggests that increased microglial ICAM-1 expression may play a role in the pathogenesis of MoMuLV (ts-1)-mediated neurodegeneration.     

Adhesion molecules in multiple sclerosis: relation to subtypes of disease and methylprednisolone therapy

OBJECTIVES: To determine levels of adhesion molecules in blood and cerebrospinal fluid (CSF) samples from patients with different subtypes and activities of multiple sclerosis (MS) and to assess the effect of intravenous methylprednisolone sodium succinate treatment on the levels of soluble adhesion molecules. DESIGN: The expressions of very late activation antigen 4 (VLA-4), lymphocyte function associated antigen 1 (LFA-1), vascular cell adhesion molecule 1 (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1) were determined immunocytochemically, and levels of soluble VCAM-1, ICAM-1, and E-selectin, by means of enzyme immunoassay technique. The volumes of T2- and T1-weighted MS plaques and brain atrophy were determined by means of the semiautomatic magnetic resonance imaging (MRI) segmentation technique. SETTING: A university hospital in Finland. PATIENTS: One hundred subjects (71 patients with MS and 29 healthy control subjects). The subtypes of MS were relapsing-remitting (RRMS [n = 26]), secondary progressive (SPMS [n = 20]), and primary progressive (PPMS [n = 25]). RESULTS: In patients with RRMS and SPMS, the expressions of VLA-4 and LFA-1 on immune cells from blood were at least 1.5- to 3-fold higher than in controls (RRMS, P = .002 and P<.001, respectively; SPMS, P = .03 and P =.001, respectively). In RRMS, LFA-1 and ICAM-1 expression in blood was more up-regulated than in SPMS (P = .03 and P = .01, respectively). The expressions of adhesion molecules on CSF lymphocytes in RRMS and SPMS were of similar magnitude, but the proportions of CSF VLA-4- and LFA-1-expressing lymphocytes were 3- to 4-fold higher than in controls (P = .04 and P = .008, respectively). The levels of serum soluble VCAM-1 were higher in SPMS than in RRMS (P = .005) or PPMS (P = .04). Intravenous methylprednisolone treatment of patients with RRMS in exacerbation caused a significant reduction in the serum levels of soluble VCAM-1 and E-selectin (P<.001). In SPMS, the volumes of T2-weighted plaques correlated with the serum level of soluble ICAM-1 (r = 0.64; P = .03). CONCLUSIONS: Up-regulated adhesion molecules in blood and CSF indicate sustained potential for inflammation in the CNS throughout the clinical spectrum of MS. Therapies interfering with cell adhesion may be of key importance in suppressing MS.     

Vascular cell adhesion molecule-1 modulation by tumor necrosis factor in experimental allergic encephalomyelitis

Anti-tumor necrosis factor (TNF) antibodies inhibit passively transferred experimental allergic encephalomyelitis (EAE) in SJL mice. The possibility that this occurs through interference in TNF's upregulation of endothelial cell adhesion molecules was investigated. Expression of both vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) on spinal cord vessels increased during EAE. The upregulation of VCAM-1 was markedly reduced or prevented by anti-TNF treatment. Leukocytic infiltration was 15-fold lower in anti-TNF-treated than diseased animals. Spinal cord endothelial expression of VCAM-1, though not ICAM-1 or fibronectin, positively correlated with the extent of T cell, B cell or monocyte infiltration in each animal.     

Adhesion and migration of polymorphonuclear leukocytes across human brain microvessel endothelial cells are differentially regulated by endothelial cell adhesion molecules and modulate monolayer permeability

The mechanisms by which polymorphonuclear leukocytes (PMN) cross the human blood-brain barrier have not been fully elucidated. Using a well characterized in vitro model of the human BBB, we examined the role of endothelial cell adhesion molecules on the adhesion and transendothelial migration of PMN across primary cultures of human brain microvessel endothelial cells (HBMEC). A small number of PMN (0.06%) adhered to unstimulated HBMEC, and the basal adhesion was not affected by anti-adhesion molecule antibodies. Treatment of HBMEC with tumor necrosis factor (TNF)-alpha resulted in increased PMN adhesion that was significantly inhibited by blocking antibodies to E-selectin and ICAM-1, but not VCAM-1 or PECAM-1. A very small number of adherent PMN migrated across unstimulated HBMEC monolayers. Migration increased 2 to 20 fold following stimulation of HBMEC with TNF-alpha. Monoclonal antibody blocking studies showed that PMN used ICAM-1, but not VCAM-1, E-selectin or PECAM-1 to move across activated monolayers. Anti-adhesion molecule antibodies did not diminish the basal PMN migration. Ultrastructurally, PMN often aggregated on top and between adjacent endothelial cells and adhered by first extending pseudopodia along the apical endothelial surface. They then flattened and inserted themselves between endothelial cells in order to migrate across the monolayers. At the end of the migration period, the cultures resumed their continuity with no evidence of disruption. Transendothelial migration of PMN decreased the transendothelial electrical resistance and increased the permeability to horseradish peroxidase, which penetrated alongside the migrating leukocytes. A blocking antibody to ICAM-1 that greatly decreased migration, had no effect on the permeability changes. These studies provide insights into the mechanisms that regulate the entry of PMN into the brain and the increased permeability of the BBB in CNS inflammation.     

Expression of ICAM-1, VCAM-1, L-selectin, and leukosialin in the mouse central nervous system during the induction and remission stages of experimental allergic encephalomyelitis

Adhesion molecules facilitate infiltration of leukocytes into the central nervous system (CNS) of mice with experimental allergic encephalomyelitis (EAE). Expression of the adhesion molecules ICAM-1 (CD54), VCAM-1 (CD106), L-selectin (CD62L), and leukosialin (CD43) was analyzed via immunocytochemistry 4–28 days after the injection of encephalitogen into EAE-susceptible SWXJ mice. Constitutive ICAM-1 expression on large-diameter CNS vessels was upregulated on post-injection days 8, 11, 14 and 18 (concurrent with de novo expression on smaller capillaries and glial cells), partially downregulated by day 23, and back to control levels by day 28, Constitutive VCAM-1 expression was upregulated by day 14 and back to control levels by day 28. Upregulation of ICAM-1 temporally coincided with the immigration of CD4⁺ lymphocytes and L-selectin⁺ leukocytes into the CNS, while downregulation coincided with their emigration. The infiltration of CDA3⁺ leukocytes also coincided with the upregulation of vascular adhesion molecules, but CDA3⁺ cells remained in the CNS after ICAM-1 and VCAM-1 had returned to control levels. Cellular infiltration and adhesion-molecule expression preceded EAE clinical symptoms by a minimum of 3 days, suggesting a causal role of adhesion molecules in the initiation of CNS inflammation. However, prophylactic injections of monoclonal antibodies against either ICAM-1, L-selectin, or CD43, did not ameliorate the clinical severity of EAE in this model.     

Endothelial cell activation following moderate traumatic brain injury

Traumatic brain injury (TBI) initiates a cascade of acute and chronic injury responses which include disturbances in the cerebrovasculature that may result in the activation of the microvascular endothelial development of a dysfunction endothelium. The present study examines endothelial cell (EC) activation in a percussion model of moderate TBI. The criteria for endothelial activation used in these studies was surface expression of a number of markers collectively termed endothelial activation antigens. Temporal induction of the major histocompatibility (MHC) class II molecules, E-selectin (CD62E), vascular cell adhesion molecule (VACM-1) (CD106) as well as altered expression of constitutively expressed intercellular adhesion molecule-1 (ICAM-1) (CD54), the glucose transporter protein (glut-1), the transferrin receptor (tfR) (CD71), and MHC class I molecules was examined at various times following impact. Induction of E-selectin and increased expression of ICAM-1 was seen by 2 h post-impact (PI) and was sustained through 24 h PI. Decreased expression of immunologically reactive glut-1 and tfR was observed by 2-4 h PI and remained low up to 24 h PI. No induction of VCAM-1, MHC class II molecules or altered constitutive expression or MHC class I molecules was seen. Changes in EC activation were observed predominantly at the site of impact and were diminished temporarily. These results indicate that mild concussive injury to the brain results in activation of the endothelium.     

Inflammatory molecule expression in cerebral arteriovenous malformations.

Inflammatory proteins may play a role in the pathophysiology of cerebral arteriovenous malformations and their response to radiosurgery. The aim of this study was to compare the expression of inflammatory molecules in arteriovenous malformations (AVMs) with that in normal cerebral vessels. Fresh-frozen surgical specimens from 15 AVMs and three control specimens were studied. The expression of P- and E-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), platelet-endothelial cell adhesion molecule (PECAM-1) and von Willebrand factor were examined using immunohistochemistry. AVMs had significant upregulation of E-selectin. VCAM-1 and ICAM-1 upregulation was also observed in AVMs. Pre-operative embolization was associated with increased expression of E-selectin and VCAM-1. This study has provided further evidence that the endothelium of AVMs has different molecular properties than the endothelium of normal cerebral vasculature. Inflammatory molecules may be biologically relevant in the response of vascular malformations to radiosurgery and embolization.     

In vitro adhesion and migration of T lymphocytes across monolayers of human brain microvessel endothelial cells: regulation by ICAM-1, VCAM-1, E-selectin and PECAM-1

Increased lymphocyte traffic across an altered blood-brain barrier (BBB) is a prominent and early event in inflammatory and immune-mediated CNS diseases. The factors that control the entry of lymphocytes into the brain have not been fully elucidated. In this study, primary cultures of human brain microvessel endothelial cells (HBMEC) were used to investigate the role of endothelial cell (EC) adhesion molecules in the adhesion and migration of peripheral blood T lymphocytes across TNF-alpha treated and untreated monolayers. Adhesion of T cells to unstimulated HBMEC was minimal and few of the adherent cells migrated across the monolayers. Treatment of HBMEC with TNF-alpha augmented adhesion by 5-fold. The binding to activated EC was significantly, but not completely, inhibited by monoclonal antibodies (mAbs) to ICAM-1 and VCAM-1, whereas adhesion to unstimulated EC was blocked by mAb to ICAM-1 but not VCAM-1. Transendothelial migration of lymphocytes increased by up to 30-fold following treatment of HBMEC with TNF-alpha. Migration across activated monolayers, but not across untreated EC, was almost completely blocked by Ab to ICAM-1 and significantly inhibited by Abs to PECAM-1 and E-selectin. VCAM-1 was not utilized during transendothelial migration. Ultrastructurally, pseudopodia from lymphocytes contacted finger-like cytoplasmic projections on EC and eventually penetrated the EC cytoplasm at focal points along the apical surface. Migrating lymphocytes moved either through the EC cytoplasm or between adjacent EC across intercellular contacts. The overlying monolayers showed no evidence of disruption and intercellular junctions appeared intact over the migrated T cells. These studies indicate that adhesion and migration of T lymphocytes across the cerebral endothelial barrier are distinct processes that depend upon the activation state of EC and are controlled by diverse receptor-ligand interactions.     

A cannabinoid agonist interferes with the progression of a chronic model of multiple sclerosis by downregulating adhesion molecules

Adhesion molecules are critical players in the regulation of transmigration of blood leukocytes across the blood–brain barrier in multiple sclerosis (MS). Cannabinoids (CBs) are potential therapeutic agents in the treatment of MS, but the mechanisms involved are only partially known. Using a viral model of MS we observed that the cannabinoid agonist WIN55,212-2 administered at the time of virus infection suppresses intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) in brain endothelium, together with a reduction in perivascular CD4⁺ T lymphocytes infiltrates and microglial responses. WIN55,212-2 also interferes with later progression of the disease by reducing symptomatology and neuroinflammation. In vitro data from brain endothelial cell cultures, provide the first evidence of a role of peroxisome proliferator-activated receptors gamma (PPARγ) in WIN55,212-2-induced downregulation of VCAM-1. This study highlights that inhibition of brain adhesion molecules by WIN55,212-2 might underline its therapeutic effects in MS models by targeting PPAR-γ receptors.     

Lymphocyte adhesion molecule ligands and extracellular matrix proteins in gliomas and normal brain: expression of VCAM-1 in gliomas

To identify antigenic differences between gliomas and normal brain, we have immunohistochemically studied the expression of lymphocyte adhesion molecules (ICAM-1, ICAM-2, ICAM-3, VCAM-1, E-selectin and CD58), epidermal growth factor receptor (EGFR) and extracellular matrix proteins (collagen IV, fibronectin, laminin, merosin, tenascin and vitronectin) in these tissues. Gliomas expressed high levels of ICAM-1, CD58 (LFA-3), EGFR, tenascin and vitronectin, whereas only very low levels were detected in normal brain. VCAM-1 expression was detected in 15 out of 25 gliomas but not in normal brain. The presence of VCAM-1 in gliomas was verified by immunoblotting and RNase protection assay, and in glioma cell lines by Northern blotting. Expression of VCAM-1 in gliomas may partially explain lymphocytic infiltration, and anti-VCAM-1 antibodies may be of potential in antibody mixtures for targeted therapy of gliomas. Received: 9 December 1996 / Revised, accepted: 20 February 1997     

Differential effects of moderate or heavy alcohol consumption on circulating adhesion molecule levels

Epidemiological studies suggest that moderate but not heavy alcohol consumption provides protection against coronary heart disease. We assessed the relationship between alcohol consumption and serum levels of adhesion molecules involved in the pathogenesis of early atherosclerosis. One-hundred apparently healthy men with similar cardiovascular risk factors were divided into four groups according to ethanol intake. Moderate drinkers (20-40 g/day) showed lower serum intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) levels than abstainers (p < 0.05; both), as well as lower serum ICAM-1, VCAM-1 and E-selectin levels than heavy drinkers (p = 0.01; all). The latter also showed higher serum ICAM-1 and E-selectin levels than abstainers (p < 0.001; both). We conclude that moderate drinkers show a significant reduction of soluble endothelial adhesion molecule levels compared to abstainers and heavy drinkers, that may contribute to the protective effect of moderate alcohol consumption against atherosclerosis.