Adhesion molecules in human pancreatic cancer.

In order to study the relevance of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and endothelial leukocyte adhesion molecule 1 (ELAM-1) for lymphocyte extravasation in the early phase of allergic contact dermatitis, the time courses of lymphocyte infiltration and adhesion molecule expression during initiation of this disorder were determined. Sequential biopsies of positive allergic patch test reactions were obtained 4, 8, 16 and 24 h after antigen application, cryostat sectioned and stained with monoclonal antibodies for ICAM-1, VCAM-1, ELAM-1 and lymphocytes by use of an immunoperoxidase technique. The slides were evaluated semiquantitatively according to appropriate gradation scales that had been defined separately for the staining with each antibody. Our results show that there is a significant upregulation of VCAM-1 and ELAM-1 expression within the first 8 h after antigen application, when lymphocyte extravasation is just beginning. In contrast, ICAM-1 is already expressed in higher levels in normal skin and is hardly enhanced during the first 8 h of patch test reactions. The main influx of lymphocytes occurs 16-24 h after antigen application and is accompanied by a further increase in all three adhesion molecules. We conclude that VCAM-1 and ELAM-1 rather than ICAM-1 may be of particular importance for the start phase of allergic contact dermatitis and that all three of them contribute to an amplification of this inflammation.

The clinical complications associated with severe and cerebral malaria occur as a result of the intravascular mechanical obstruction of erythrocytes infected with the asexual stages of the parasite, Plasmodium falciparum. We now report that a primary P. falciparum- infected erythrocyte (parasitized red blood cell [PRBC]) isolate from a patient with severe complicated malaria binds to cytokine-induced human vascular endothelial cells, and that this adhesion is in part mediated by endothelial leukocyte adhesion molecule 1 (ELAM-1) and vascular cell adhesion molecule 1 (VCAM-1). PRBC binding to tumor necrosis factor alpha (TNF-alpha)-activated human vascular endothelial cells is partially inhibited by antibodies to ELAM-1 and ICAM-1 and the inhibitory effects of these antibodies is additive. PRBCs selected in vitro by sequential panning on purified adhesion molecules bind concurrently to recombinant soluble ELAM-1 and VCAM-1, and to two previously identified endothelial cell receptors for PRBCs, ICAM-1, and CD36. Post-mortem brain tissue from patients who died from cerebral malaria expressed multiple cell adhesion molecules including ELAM-1 and VCAM-1 on cerebral microvascular endothelium not expressed in brains of individuals who died from other causes. These results ascribe novel pathological functions for both ELAM-1 and VCAM-1 and may help delineate alternative adhesion pathways PRBCs use to modify malaria pathology.

Upregulation of adhesion proteins plays an important role in mediating inflammation. The induction of adhesive molecules has been well studied, but the reversibility of their expression has not been well characterized. A neutralizing anti-TNF monoclonal antibody (cA2) was used to study the down regulation of TNF-induced E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) on cultured human umbilical vein endothelial cells (HUVECs). Addition of cA2 following TNF stimulation of HUVECs enhanced the rate of E-selectin and VCAM-1 down-regulation from the cell surface and also reduced steady state E-selectin and VCAM-1 mRNA levels. The cA2-mediated disappearance of E-selectin, but not VCAM-1 protein was microtubule and not microfilament dependent. Neutralization of TNF only slightly reduced ICAM-1 cell surface levels following initial TNF stimulation, suggesting a slower turnover of ICAM-1 compared to E-selectin and VCAM-1. Microtubule inhibition during TNF stimulation partially inhibited E-selectin, VCAM-1 and ICAM-1 mRNA upregulation. VCAM-1 and ICAM-1 cell surface expression were similarly partially inhibited, however, E-selectin levels were unaffected, presumably due to the dual, opposing effect of inhibiting protein expression and inhibiting internalization. Microfilament inhibition during protein induction specifically inhibited the maximal expression of VCAM-1 protein and mRNA, without affecting E-selectin or ICAM-1. These data support the notion that E-selectin, VCAM-1, and ICAM-1 expression are differentially regulated on HUVECs and suggest that TNF neutralizing therapies may be effective because of their ability to reduce the levels of pre-existing adhesion proteins.

The present studies were performed to explore potentially selective mechanisms of leukocyte adhesion in an attempt to understand how preferential recruitment of eosinophils and basophils might occur during allergic and other inflammatory reactions. Stimulation of human vascular endothelial cells for 24 h with IL-4 (30 to 1,000 U/ml) induced adhesion for eosinophils (up to approximately four-fold of control) and basophils (up to approximately twofold of control) but not neutrophils (less than 125% of control). Analysis of endothelial expression of adhesion molecules by flow cytometry revealed that IL-4 treatment induced vascular cell adhesion molecule-1 (VCAM-1) expression without significantly affecting the expression of other adhesion molecules, namely endothelial-leukocyte adhesion molecule-1 (ELAM-1) or intercellular adhesion molecule-1 (ICAM-1). The concentration-response curve for IL-4-induced VCAM-1 expression paralleled that for adhesion. Endothelial cells stimulated with IL-4 expressed adhesive properties for eosinophils by 3 h; the response increased steadily during a 24-h time course study. Eosinophils and basophils adhered to plates coated with a recombinant form of VCAM-1. This adhesion was blocked with antibodies to VCAM-1 but not ELAM-1. mAb directed against either VCAM-1 or VLA-4 inhibited (by approximately 75%) the binding of eosinophils and basophils to IL-4-stimulated endothelial cells. Because VLA-4 and VCAM-1 have been demonstrated to bind to each other in other adhesion systems, these results suggest that IL-4 stimulates eosinophil and basophil adhesion by inducing endothelial cell expression of VCAM-1 which binds to eosinophil and basophil VLA-4. The lack of expression of VLA-4 on neutrophils and the failure of IL-4 to stimulate neutrophil adherence support this conclusion. It is proposed that local release of IL-4 in vivo in allergic diseases or after experimental allergen challenge may partly explain the enrichment of eosinophils and basophils (vs neutrophils) observed in these situations.

Expression of Stress Proteins, Adhesion Molecules, and Interleukin-8 in Endothelial Cells after Preservation and Reoxygenation

Cell-Surface Proteomics to Unravel Cytokine-Induced Endothelial Activation

Role of Adhesion Molecule Expression and Soluble Fractions in Hepatic Resection

Porphyromonas gingivalis has been shown to actively invade endothelial cells and induce vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) overexpression. Nucleotide-binding oligomerization domain 1 (NOD1) is an intracellular pattern recognition reporter, and its involvement in this process was unknown. This study focused on endothelial cells infected with P.gingivalis, the detection of NOD1 expression and the role that NOD1 plays in the upregulation of VCAM-1 and ICAM-1. The human umbilical vein endothelial cell line (ECV-304) was intruded by P.gingivalis W83, and cells without any treatment were the control group. Expression levels of NOD1, VCAM-1, ICAM-1, phosphorylated P65 between cells with and without treatment on both mRNA and protein levels were compared. Then we examined whether mesodiaminopimelic acid (NOD1 agonist) could increase VCAM-1 and ICAM-1 expression, meanwhile, NOD1 gene silence by RNA interference could reduce VCAM-1, ICAM-1 and phosphorylated P65 release. At last, we examined whether inhibition of NF-κB by Bay117082 could reduce VCAM-1 and ICAM- 1 expression. The mRNA levels were measured by real-time polymerase chain reaction, and protein levels by western blot or electrophoretic mobility shift assays (for phosphorylated P65). P.gingivalis invasion showed significant upregulation of NOD1, VCAM-1 and ICAM-1. NOD1 activation by meso-diaminopimelic acid increased VCAM-1 and ICAM-1 expression, and NOD1 gene silence reduced VCAM-1 and ICAM-1 release markedly. The NF-κB signaling pathway was activated by P.gingivalis, while NOD1 gene silence decreased the activation of NF-κB. Moreover, inhibition of NF-κB reduced VCAM-1 and ICAM-1 expression induced by P.gingivalis in endothelial cells. The results revealed that P.gingivalis induced NOD1 overexpression in endothelial cells and that NOD1 played an important role in the process of VCAM-1 and ICAM-1 expression in endothelial cells infected with P.gingivalis through the NF-κB signaling pathway.

Monocytes recruitment and adhesion to the endothelium are critical steps in the early phase of atherosclerosis and are mediated by specific adhesion molecules on endothelium and monocytes. 3,4 oxo-isopropylidene-shikimic acid ( ISA ) was one of the derivatives of shikimic acid which was extracted from the Chinese herb Bajiao Huixiang ( Illicium verm Hookfil ). Here, we investigated the effect of ISA on the key early atherogenic events of monocytes adhesion to endothelial cells and adhesion molecule expression. Adhesion was assessed by MTT assay. Cell-ELISA and RT-PCR were employed to examine the expression of intercellular adhesion molecule-1 ( ICAM-1 ) and vascular cell adhesion molecule-1 ( VCAM-1 ). The nuclear translocation of NF-kB was detected by immunocytochemistry. Pretreatment of human umbilical vein endothelial cells ( HUVEC ) with ISA ( 1-100 ¦Ìmol/L ) significantly reduced U937 monocytes adhesion to TNF-a-induced HUVEC in a dose-dependent manner whereas exerted no effect on monocytes adhesion to normal HUVEC. The expression of adhesion molecules ICAM-1 and VCAM-1 induced by TNF-a 400 ( kU/L ) were significantly inhibited by ISA ( 10 and 100 ¦Ìmol/L ). ISA also suppressed the mRNA expression of ICAM-1 and VCAM-1, but did not suppress the nuclear translocation of NF-kB induced by TNF-a. Taken together, our results first demonstrate that ISA inhibited the adhesion of U937 monocyte to HUVEC by down-regulation of the expression of ICAM-1, VCAM-1 on HUVEC. (Project supported by the State Science and Technology Commission grant, No2001BA701A07-14, P.R. China)

Immune receptors and adhesion molecules in human pulmonary leptospirosis

Cardiopulmonary bypass (CPB) may be associated with the risk of a "whole body inflammation." Adhesion molecules, such as endothelial leukocyte adhesion molecule (ELAM-1), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1), seem to play a pivotal role in the inflammatory response. Soluble forms of these adhesion molecules may serve as markers of endothelial activation or damage. To elucidate whether plasma levels of soluble adhesion molecules differ between pediatric and adult cardiac surgery patients, 15 consecutive children younger than 5 yr undergoing CPB were prospectively studied and compared with adults scheduled for elective coronary artery bypass grafting and valve replacement. Plasma levels of circulating (soluble) adhesion molecules (sELAM-1, sICAM-1, sVCAM-1) were measured from arterial blood samples using enzyme-linked immunosorbent assays after induction of anesthesia (= "baseline"), during CPB, at the end of surgery, and on postoperative days 1 and 2. At baseline, plasma levels of all three soluble adhesion molecules were significantly higher in children than in adults. sELAM-1 and sICAM-1 plasma concentrations were even beyond normal in the children (sELAM-1: 88.8 +/- 13.8 ng/mL; sICAM-1: 349 +/- 27 ng/mL). During CPB and until the end of surgery, plasma levels of all adhesion molecules decreased in the children and remained almost unchanged in the adults. In the children, sELAM-1 remained lower than baseline values until the second postoperative day (45.2 +/- 12.2 ng/mL), whereas sICAM-1 increased in the postbypass period without, however, reaching baseline values (254 +/- 40 ng/mL).(ABSTRACT TRUNCATED AT 250 WORDS)

Puerarin inhibits the inflammatory response in atherosclerosis via modulation of the NF-κB pathway in a rabbit model.

To compare intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) serum levels between patients with stable (SAP) and unstable angina pectoris (USAP) undergoing coronary angiography (CAG), investigate effects of CAG on ICAM-1, VCAM-1 levels in SAP, USAP patients; probable different effects of non-ionic radiocontrast media (RCM), iso-osmotic iodixanol and low osmolar iopamidol, on these adhesion molecules (AM). In this randomized, prospective study, 2 groups consisting of patients with SAP (n=22) and USAP (n=22) undergoing CAG were included. For halves of each group iopamidol, for the other halves iodixanol were used as RCM, in turn for randomization. The patients were divided into 4 subgroups according to clinical presentations and used RCM(SAP-iodixanol, SAP-iopamidol USAP-iodixanol, USAP-iopamidol). ICAM-1, VCAM-1 levels were measured just before and 12 hours after CAG. Repeated measurements were compared with two-way ANOVA test. Baseline VCAM-1 concentration was higher in USAP group than SAP group (p=0.001). ICAM-1, VCAM-1 concentrations increased significantly following CAG in SAP, USAP groups. ICAM-1, VCAM-1 concentration increments; didn't reach statistical significance in SAP-iodixanol subgroup, reached a borderline significance in SAP-iopamidol subgroup (p=0.06). In USAP-iodixanol subgroup; only VCAM-1 (p<0.001), in USAP-iopamidol subgroup; ICAM-1 (p=0.009), VCAM-1 (p=0.006) levels increased significantly following CAG. No complication was observed. To our knowledge, this is the first study indicating ICAM-1, VCAM-1 inducing effect of CAG in patients with SAP, USAP and differential effects of iodixanol and iopamidol on ICAM-1, VCAM-1 serum levels. Further studies are needed to clarify the effects of CAG and different RCM on vascular inflammation, vessel injury, serum AM levels and their clinical significance. This study should be taken as a pilot, hypothesis-generating study.

To assess the effects of the angiotensin-converting enzyme inhibitor enalaprilat on endothelial cells in septic patients. Prospective, randomized, placebo-controlled, blinded study. Clinical investigation on a surgical intensive care unit of a university hospital. Forty surgical septic patients (noncardiac/nonneurosurgical patients). After inclusion in the study and after baseline data were obtained, either 0.25 mg/hr (enalaprilat group, n = 20) or saline solution as placebo (control group, n = 20) was continuously given and continued throughout the following 5 days. Extensive hemodynamic monitoring was carried out in all patients. Plasma concentrations of endothelin-1, angiotensin II, soluble thrombomodulin, and soluble adhesion molecules (endothelial leukocyte adhesion molecule-1, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and granule membrane protein-140) were measured from arterial blood samples. All measurements were carried out before the start of the infusion ("baseline" values) and daily during the following 5 days. All endothelial-derived substances (thrombomodulin, endothelin-1, and all soluble adhesion molecules) were similarly increased beyond normal in both group. Endothelin-1 increased only in the untreated control patients (from 6.9 +/- 0.7 to 14.3 +/- 1.4 mg/mL). Soluble thrombomodulin increased in the untreated control patients (from 58 +/- 9 to 79 +/- 14 ng/mL [p < .05]), but significantly decreased in the enalaprilat-treated patients. Soluble adhesion molecules increased in the untreated control group (endothelial leukocyte adhesion molecule from 92 +/- 14 to 192 +/- 29 ng/mL; intercellular adhesion molecule-1 from 480 +/- 110 to 850 +/- 119 ng/ mL) and returned almost to normal values in the enalaprilat patients. The survival rate did not differ significantly between the two groups. Control patients developed severe sepsis and septic shock more often than the enalaprilat-treated group. The complex pathogenesis of endothelial function abnormalities in sepsis may offer a large number of pharmacologic interventions. Administration of the angiotensin-converting enzyme inhibitor enalaprilat resulted in a reduced release of soluble endothelial-derived substances into the circulating blood, which may indicate an improved endothelial function. The specific actions of enalaprilat on the endothelium have to be elucidated in further studies.

The adhesion of leukocytes to endothelial cells (EC) is the first step required for the migration of leukocytes from blood to the tissue at sites of inflammation. These leukocyte-EC interactions are mediated by surface proteins (adhesion molecules) on both the leukocytes and the EC. Adhesion molecules that play a role in leukocyte-EC interactions are the β1- and β2-integrins on leukocytes and granule membrane protein-140 (GMP-140), endothelial leukocyte adhesion molecule-1 (ELAM-1), intercellular adhesion molecule-1 and 2 (ICAM-1 and ICAM-2) and vascular cell adhesion molecule-1 (VCAM-1) on EC. From earlier studies (1–11) with cultured human EC it is known that cytokines, like IL-la and TNF-a, can induce or up-regulate membrane expression of adhesion molecules on EC, thereby increasing leukocyte adhesion to the endothelium. Stimulation of EC with, for example, IL-la or TNF-a induces ELAM-1, an adhesion molecule involved in monocyte and granulocyte adhesion (2, 6). On the other hand IFN-7 increases the adhesiveness of EC for both monocytes and lymphocytes but not for neutrophils (12). Therefore the local production and release of various cytokines regulates the type and number of infiltrating leukocytes at the site of inflammation.