The adhesion molecules of inflammation

A systematic review and meta-analysis of circulating adhesion molecules in rheumatoid arthritis

BACKGROUND

The availability of robust biomarkers of endothelial activation might enhance the identification of subclinical atherosclerosis in rheumatoid arthritis (RA). We investigated this issue by conducting a systematic review and meta-analysis of cell adhesion molecules in RA patients.

METHODS

We searched electronic databases from inception to 31 July 2023 for case-control studies assessing the circulating concentrations of immunoglobulin-like adhesion molecules (vascular cell, VCAM-1, intercellular, ICAM-1, and platelet endothelial cell, PECAM-1, adhesion molecule-1) and selectins (E, L, and P selectin) in RA patients and healthy controls. Risk of bias and certainty of evidence were assessed using the JBI checklist and GRADE, respectively.

RESULTS

In 39 studies, compared to controls, RA patients had significantly higher concentrations of ICAM-1 (standard mean difference, SMD = 0.81, 95% CI 0.62-1.00, p < 0.001; I2 = 83.0%, p < 0.001), VCAM-1 (SMD = 1.17, 95% CI 0.73-1.61, p < 0.001; I2 = 95.8%, p < 0.001), PECAM-1 (SMD = 0.82, 95% CI 0.57-1.08, p < 0.001; I2 = 0.0%, p = 0.90), E-selectin (SMD = 0.64, 95% CI 0.42-0.86, p < 0.001; I2 = 75.0%, p < 0.001), and P-selectin (SMD = 1.06, 95% CI 0.50-1.60, p < 0.001; I2 = 84.8%, p < 0.001), but not L-selectin. In meta-regression and subgroup analysis, significant associations were observed between the effect size and use of glucocorticoids (ICAM-1), erythrocyte sedimentation rate (VCAM-1), study continent (VCAM-1, E-selectin, and P-selectin), and matrix assessed (P-selectin).

CONCLUSIONS

The results of our study support a significant role of cell adhesion molecules in mediating the interplay between RA and atherosclerosis. Further studies are warranted to determine whether the routine use of these biomarkers can facilitate the detection and management of early atherosclerosis in this patient group. PROSPERO Registration Number: CRD42023466662.

Study of blood rheological parameters and NO in coronary artery disease patients with and without collaterals

BACKGROUND

In coronary artery disease (CAD), an alternative way of improvement of blood circulation in the ischemic area of the myocardium is coronary collateral circulation. Our study aimed to investigate the rheological parameters of blood and nitric oxide (NO) content in patients with various degrees of collateral development and the likelihood of the influence of blood fluidity on collateral angiogenesis.

METHODS

We studied patients with stable CAD who underwent elective coronary angiography and a control group with the same mean age. We investigated patients with different degrees of developing collaterals and those without them. In studied patients, the blood plasma viscosity, aggregability, and deformability of erythrocytes, as the main indicators of blood rheology. We recorded content of stable metabolic end products of nitric oxide (NOx).

RESULTS

Results of the studies showed that in the blood of studied patients with CAD erythrocyte aggregation was increased and NO content decreased compared to the control level; NO content was as lower, as less was the number of developed collaterals was recorded.

CONCLUSION

In this work, the role of the aggregation ability of erythrocytes and the endothelial origin of NO in the direct and feedback regulatory mechanism of angiogenesis in patients with CAD are discussed.

Modelling inflammatory biomarker dynamics in a human lipopolysaccharide (LPS) challenge study using delay differential equations

Clinical studies in healthy volunteers challenged with lipopolysaccharide (LPS), a constituent of the cell wall of Gram-negative bacteria, represent a key model to characterize the Toll-like receptor 4 (TLR4)-mediated inflammatory response. Here, we developed a mathematical modelling framework to quantitatively characterize the dynamics and inter-individual variability of multiple inflammatory biomarkers in healthy volunteer LPS challenge studies. Data from previously reported LPS challenge studies were used, which included individual-level time-course data for tumour necrosis factor α (TNF-α), interleukin 6 (IL-6), interleukin 8 (IL-8) and C-reactive protein (CRP). A one-compartment model with first-order elimination was used to capture the LPS kinetics. The relationships between LPS and inflammatory markers was characterized using indirect response (IDR) models. Delay differential equations were applied to quantify the delays in biomarker response profiles. For LPS kinetics, our estimates of clearance and volume of distribution were 35.7 L h^-1 and 6.35 L, respectively. Our model adequately captured the dynamics of multiple inflammatory biomarkers. The time delay for the secretion of TNF-α, IL-6 and IL-8 were estimated to be 0.924, 1.46 and 1.48 h, respectively. A second IDR model was used to describe the induced changes of CRP in relation to IL-6, with a delayed time of 4.2 h. The quantitative models developed in this study can be used to inform design of clinical LPS challenge studies and may help to translate preclinical LPS challenge studies to humans.

Poly (ADP-ribose) polymerase: An Overview of Mechanistic Approaches and Therapeutic Opportunities in the Management of Stroke

Stroke is one of the leading causes of morbidity and mortality accompanied by blood supply loss to a particular brain area. Several mechanistic approaches such as inhibition of poly (ADP-ribose) polymerase, therapies against tissue thrombosis, and neutrophils lead to stroke's therapeutic intervention. Evidence obtained with the poly (ADP-ribose) polymerase (PARP) inhibition and animals having a deficiency of PARP enzymes; represented the role of PARP in cerebral stroke, ischemia/reperfusion, and neurotrauma. PARP is a nuclear enzyme superfamily with various isoforms, each with different structural domains and functions, and out of all, PARP-1 is the best-characterized member. It has been shown to perform multiple physiological as well as pathological processes, including its role in inflammation, oxidative stress, apoptosis, and mitochondrial dysfunction. The enzyme interacts with NF-κB, p53, and other transcriptional factors to regulate survival and cell death and modulates multiple downstream signaling pathways. Clinical trials have also been conducted using PARP inhibitors for numerous disorders and have shown positive results. However, additional information is yet to be established for the therapeutic intervention of PARP inhibitors in stroke. These agents' utilization appears to be challenging due to their unknown potential long-term side effects. PARP activity increased during ischemia, but its inhibition provided significant neuroprotection. Despite the increased interest in PARP as a pharmacological modulator for novel therapeutic therapies, the current review focused on stroke and poly ADP-ribosylation.

Natural Compounds as Target Biomolecules in Cellular Adhesion and Migration: From Biomolecular Stimulation to Label-Free Discovery and Bioactivity-Based Isolation

Plants and fungi can be used for medical applications because of their accumulation of special bioactive metabolites. These substances might be beneficial to human health, exerting also anti-inflammatory and anticancer (antiproliferative) effects. We propose that they are mediated by influencing cellular adhesion and migration via various signaling pathways and by directly inactivating key cell adhesion surface receptor sites. The evidence for this proposition is reviewed (by summarizing the natural metabolites and their effects influencing cellular adhesion and migration), along with the classical measuring techniques used to gain such evidence. We systematize existing knowledge concerning the mechanisms of how natural metabolites affect adhesion and movement, and their role in gene expression as well. We conclude by highlighting the possibilities to screen natural compounds faster and more easily by applying new label-free methods, which also enable a far greater degree of quantification than the conventional methods used hitherto. We have systematically classified recent studies regarding the effects of natural compounds on cellular adhesion and movement, characterizing the active substances according to their organismal origin (plants, animals or fungi). Finally, we also summarize the results of recent studies and experiments on SARS-CoV-2 treatments by natural extracts affecting mainly the adhesion and entry of the virus.

Natural Formulations: Novel Viewpoint for Scleroderma Adjunct Treatment

BACKGROUND

Scleroderma is a complex disease involving autoimmune, vascular, and connective tissues, with unknown etiology that can progress through any organ systems.

OBJECTIVE

Yet, no cure is available; the thorough treatment of scleroderma and current treatments are based on controlling inflammation. Nowadays, medicinal plants/natural-based formulations are emerging as important regulators of many diseases, including autoimmune diseases. Here, we provided an overview of scleroderma, also focused on recent studies on medicinal plants/natural-based formulations that are beneficial in scleroderma treatment/prevention.

METHODS

This study is the result of a search in PubMed, Scopus, and Cochrane Library with "scleroderma", "systemic sclerosis", "plant", "herb", and "phytochemical" keywords. Finally, 22 articles were selected from a total of 1513 results entered in this study.

RESULTS

Natural products can modulate the inflammatory and/or oxidative mediators, regulate the production or function of the immune cells, and control the collagen synthesis, thereby attenuating the experimental and clinical manifestation of the disease.

CONCLUSION

Natural compounds can be considered an adjunct treatment for scleroderma to improve the quality of life of patients suffering from this disease.

Biomarkers Associated with Atrial Fibrosis and Remodeling

Atrial fibrillation is the most common rhythm disturbance encountered in clinical practice. Although often considered as solely arrhythmic in nature, current evidence has established that atrial myopathy constitutes both the substrate and the outcome of atrial fibrillation, thus initiating a vicious, self-perpetuating cycle. This myopathy is triggered by stress-induced (including pressure/volume overload, inflammation, oxidative stress) responses of atrial tissue, which in the long term become maladaptive, and combine elements of both structural, especially fibrosis, and electrical remodeling, with contemporary approaches yielding potentially useful biomarkers of these processes. Biomarker value becomes greater given the fact that they can both predict atrial fibrillation occurrence and treatment outcome. This mini-review will focus on the biomarkers of atrial remodeling (both electrical and structural) and fibrosis that have been validated in human studies, including biochemical, histological and imaging approaches.

Toxic proteins from Croton tiglium L. exert a proinflammatory effect by inducing release of proinflammatory cytokines and activating the p38-MAPK signaling pathway

The aim of the present study was to determine the toxic targets of proteins from Croton tiglium L. and to investigate the potential mechanism of their toxicity. The toxic targets were determined by oral medication and intraperitoneal injection. The median lethal dose of oral medication in mice was calculated using Bliss software (2,752.8–3,407.5 mg/kg), and that of intraperitoneal injection was 195.8–272.69 mg/kg. The results of histopathological examination demonstrated that the kidney was primarily impaired by intraperitoneal injection, with slight degeneration of renal tubular epithelial cells. As to oral medication, the digestive tract was primarily injured, which manifested as congestion, bleeding, serious edema and other symptoms. Oral administration of the proteins caused gastrointestinal edema by increasing the intestinal permeability. Severe edema was associated with the inflammatory response, therefore the association between the toxicity of the proteins and inflammation was investigated. The proinflammatory effects of the crude proteins on the release of inflammatory mediator prostaglandin E2 (PGE2) were evaluated through intraperitoneal injection and the production of proinflammatory cytokines in RAW264.7 macrophages. Maximum PGE2 was released in the mice in vivo following intraperitoneal injection with 400 mg crude protein/kg body weight. Proinflammatory cytokines in macrophages, including tumor necrosis factor-α and interleukin-1β, were produced in dose- and time-dependent manners in vitro. furthermore, the expressions of cell signaling molecules were detected by western blotting. The inflammatory response induced by crude protein in macrophages was associated with the mitogen-activated protein kinase (MAPK) signaling pathway mainly including p38-MAPK, extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase 1/2/3 and the activated p38-MAPK signaling pathway. However, extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinases 1–3 exhibited no significant response.

The Distribution of Activation Markers and Selectins on Peripheral T Lymphocytes in Preeclampsia

Introduction

Impaired maternal immune tolerance resulting in systemic inflammation plays a pivotal role in the pathogenesis of preeclampsia. Phenotypical changes of monocytes and neutrophil granulocytes have already been studied in preeclampsia, and some studies also included T lymphocyte activation markers; however, the results are controversial and a comprehensive analysis of activation markers is lacking. The characteristics of cellular adhesion molecules in preeclampsia are yet to be described.

Material and Methods

Peripheral blood samples of 18 preeclamptic patients and 20 healthy pregnant women in the third trimester were evaluated using flow cytometry to characterize the cell surface expression of T lymphocyte activation markers and selectins.

Results

We found an elevated ratio of HLA-DR and CD122-, CD62E-, and CD62L-expressing cells among the CD4+ T lymphocytes in PE in comparison to healthy pregnancy. No alterations were found in the prevalence of CD69-, CD25-, and CD62P-expressing lymphocytes and CD11c-expressing monocytes.

Conclusions

Our findings support the role of activated T lymphocytes and specific cell adhesion molecules in the pathogenesis of preeclampsia.

Controlled Ovarian Hyperstimulation—An Inflammatory State

OBJECTIVE

Controlled ovarian hyperstimulation (COH) is apparently a key factor in the success of in vitro fertilization-embryo transfer. One of the major complications of COH is severe ovarian hyperstimulation syndrome (OHSS), which may be attributable to a massive increase in systemic inflammatory cytokines or to neutrophil activation. The aim of the present review was to investigate the role of COH in the induction of an inflammatory response.

METHODS

Major studies that have reported on the association between COH and inflammation were identified through MEDLINE searches and the published literature.

RESULTS

Several inflammatory mediators, namely, C-reactive protein and leukocyte and endothelial selectins, showed a significant increase after human chorionic gonadotropin (hCG) administration in vivo, reflecting an inflammatory state, and neutrophil and endothelial activation, respectively. On the other hand, hCG showed a direct depressive effect on mononuclear cells in vitro. Because the development of OHSS almost always follows hCG administration, the negative effect of hCG on peripheral mononuclear cells indicates that it probably causes OHSS by an indirect mechanism.

CONCLUSION

We suspect that hCG stimulates the ovaries to produce and secrete a still unknown intermediate factor, which in turn activates inflammatory processes that may lead to an increase in capillary permeability.

Atrial fibrillation coincides with the advanced glycation end product N(ε)-(carboxymethyl)lysine in the atrium

Presence of advanced glycation end products (AGEs) in the heart induces a proinflammatory phenotype. However, the presence of AGEs within atrial tissue of atrial fibrillation (AF) patients is unknown and was analyzed here. Left atrial appendage tissue from 33 AF patients and 9 controls was analyzed for the presence of the major AGEs N(ε)-(carboxymethyl)lysine (CML), VCAM-1, neutrophilic granulocytes, lymphocytes, and macrophages in both the fat tissue and myocardium separately. The total amount of fibrosis was also analyzed. Presence of CML was significantly higher in blood vessels of the left atrial appendage in AF patients as compared to controls, independent of diabetes mellitus. In AF patients, VCAM-1 expression in blood vessels and the numbers of infiltrated neutrophilic granulocytes, lymphocytes, and macrophages significantly increased compared to controls, and were highest in the fat tissue; there was no significant difference in fibrosis compared to controls. Interestingly, total amount of CML and fibrosis in AF and control patients correlated positively. Finally, there was no difference between AF patients based on AF type or surgical indication in the presence of CML, VCAM-1 expression, inflammatory cells, and fibrosis. Our results indicate that in AF the intramyocardial blood vessels of the left atrial appendage have an increased CML presence and proinflammatory status coinciding with a local increase in the number of inflammatory cells.

Pinellia ternata lectin exerts a pro-inflammatory effect on macrophages by inducing the release of pro-inflammatory cytokines, the activation of the nuclear factor-κB signaling pathway and the overproduction of reactive oxygen species

Pinellia ternata (PT) is a widely used traditional Chinese medicine. The raw material has a throat-irritating toxicity that is associated with the PT lectin (PTL). PTL is a monocot lectin isolated from the tubers of PT, which exhibits mouse peritoneal acute inflammatory effects in vivo. The present study aimed to investigate the pro-inflammatory effect of PTL on macrophages. PTL (50 µg/ml)‑stimulated macrophages enhanced the chemotactic activity of neutrophils. PTL (50, 100, 200 and 400 µg/ml) significantly elevated the production of cytokines [tumor necrosis factor‑α (TNF-α) , interleukin (IL)‑1β and IL‑6]. PTL (25, 50 and 100 µg/ml) induced intracellular reactive oxygen species (ROS) overproduction. PTL also caused transfer of p65 from the macrophage cytoplasm to the nucleus and activated the nuclear factor‑κB (NF‑κB) signaling pathway. Scanning electron microscope images revealed severe cell swelling and membrane integrity defection of macrophages following PTL (100 µg/ml) stimulation, which was also associated with inflammation. PTL had pro‑inflammatory activity, involving induced neutrophil migration, cytokine release, ROS overproduction and the activation of the NF-κB signaling pathway, which was associated with the activation of macrophages.

Intraocular soluble intracellular adhesion molecule-1 correlates with subretinal fluid height of diabetic macular edema

Objective:

To investigate the correlations between aqueous concentrations of vascular endothelial growth factor (VEGF), monocyte chemoattractant protein-1 (MCP-1), soluble intracellular adhesion molecule-1 (sICAM-1) and diabetic macular edema (DME).

Materials and Methods:

VEGF, MCP-1 and sICAM-1 concentrations in aqueous humor samples of 22 patients with DME and 23 patients with cataract of a control group were measured with solid-phase chemiluminescence immunoassay.

Results:

Aqueous VEGF (89.2 ± 58.5 pg/ml versus 48.5 ± 27.8 pg/ml, P = 0.006), MCP-1 (684.2 ± 423.4 pg/ml versus 432.4 ± 230.4 pg/ml, P = 0.019) and sICAM-1 (3213.8 ± 2581.6 pg/ml versus 260.2 ± 212.2 pg/ml, P < 0.001) all vary significantly between DME group and control group. Maximum height of submacular fluid measured by Optical coherence tomography (OCT) was significantly associated with aqueous sICAM-1 (r = -0.45, P = 0.034). The maximum height of macular thickness measured by OCT was not significantly associated with either VEGF (P = 0.300), MCP-1 (P = 0.320) or sICAM-1 (P = 0.285).

Conclusions:

Our results suggest that sICAM-1 may majorly contribute to the formation of subretinal fluid in DME patients and imply that MCP-1 and sICAM-1 may be the potential therapy targets, besides VEGF.

Tryptase is a candidate autoantigen in rheumatoid arthritis

Autoimmune processes have been implicated in the development of rheumatoid arthritis (RA); however, specific autoantigens that play a role in the aetiology of RA have been lacking. In this study, we found that sera from RA patients were particularly immunoreactive against the protein tryptase. Compared with osteoarthritis (OA) patients and healthy controls, RA patients had relatively higher levels of tryptase and concomitant anti-tryptase antibodies in their synovial tissues and sera. Similarly, synovial fluid from RA patients, but not from OA patients, contained antibodies that recognized tryptase in vitro. In addition, serum tryptase levels in both early and late RA patients significantly correlated with clinical indices usually used to diagnose RA, such as rheumatoid factor, Disease Activity Score using 28 joint counts and autoantibodies against cyclic citrullinated peptide. Our results identify tryptase as a candidate autoantigen involved in the pathogenesis of RA and monitoring its levels may have diagnostic and prognostic value.

Local and systemic inflammatory responses to experimentally induced gingivitis

This study profiled the local and systemic inflammatory responses to experimentally induced gingivitis. Eight females participated in a 21-day experimental gingivitis model followed by a 14-day resolution phase. Bleeding on probing and plaque index scores were assessed before, during, and after resolution of gingival inflammation, and samples of saliva, GCF, and plasma were collected. Samples were assessed for biomarkers of inflammation using the BioPlex platform and ELISA. There were no significant changes in GCF levels of cytokines during the experimental phase; however, individual variability in cytokine profiles was noted. During resolution, mean GCF levels of IL-2, IL-6, and TNF-α decreased and were significantly lower than baseline levels (P = 0.003, P = 0.025, and P = 0.007, resp.). Furthermore, changes in GCF levels of IL-2, IL-6, and TNF-α during resolution correlated with changes in plaque index scores (r = 0.88, P = 0.004; r = 0.72, P = 0.042; r = 0.79, P = 0.019, resp.). Plasma levels of sICAM-1 increased significantly during the experimental phase (P = 0.002) and remained elevated and significantly higher than baseline levels during resolution (P < 0.001). These results support the concept that gingivitis adds to the systemic inflammatory burden of an individual.

Mechanistic aspects of inflammation and clinical management of inflammation in acute gouty arthritis

It has been recently demonstrated that interleukin 1β (IL-1β) plays a central role in monosodium urate crystal-induced inflammation and that the NALP3 inflammasome plays a major role in IL-1β production. These discoveries have offered new insights into the pathogenesis of acute gouty arthritis. In this review, we discuss the molecular mechanisms by which monosodium urate crystals induce acute inflammation and examine the mechanisms of action (MOAs) of traditional anti-inflammatory drugs (e.g., nonsteroidal anti-inflammatory drugs, colchicine, and glucocorticoids) and biologic agents (e.g., the IL-1β antagonists anakinra, rilonacept, and canakinumab) to understand how their MOAs contribute to their safety profiles. Traditional anti-inflammatory agents may act on the IL-1β pathway at some level; however, their MOAs are broad-ranging, unspecific, and biologically complex. This lack of specificity may explain the range of systemic adverse effects associated with them. The therapeutic margins of nonsteroidal anti-inflammatory drugs, colchicine, and glucocorticoids are particularly low in elderly patients and in patients with cardiovascular, metabolic, or renal comorbidities that are frequently associated with gouty arthritis. In contrast, the IL-1β antagonists act on very specific targets of inflammation, which may decrease the potential for systemic adverse effects, although infrequent but serious adverse events (including infection and administration reactions) have been reported. Because these IL-1β antagonists target an early event immediately downstream from NALP3 inflammasome activation, they may provide effective alternatives to traditional agents with minimal systemic adverse effects. Results of ongoing trials of IL-1β antagonists will likely provide clarification of their potential role in the management of acute gouty arthritis.

A study of the Interaction Between Cetirizine and Plasma Membrane of Eosinophils, Neutrophils, Platelets and Lymphocytes using A fluorescence Technique

The effect of cetirizine on plasma membrane fluidity and heterogeneity of human eosinophils, neutrophils, platelets and lymphocytes was investigated using a fluorescence technique. Membrane fluidity and heterogeneity were studied by measuring the steady-state fluorescence anisotropy and fluorescence decay of 1-(4- trimethylammonium-phenyl)-6-phenyl-1, 3, 5-hexatriene (TMA-DPH) incorporated in the membrane. The results demonstrate that cetirizine (1 μg/ml) induced a significant increase in the Hpid order in the exterior part of the membrane and a decrease in membrane heterogeneity in eosinophils, neutrophils and platelets. Moreover, cetirizine blocked the PAF induced changes in membrane fluidity in these cells. Cetirizine did not influence significantly the plasma membrane of lymphocytes. These data may partially explain the effect ofcetirizine on inflammatory cell activities.

Anti-inflammatory effect of glucose-mannose binding lectins isolated from Brazilian beans

Selectins are essential for leukocyte recruitment in inflammation. Because of a lectin domain present in the selectin structure, we investigated the anti-inflammtory activity of six mannose–glucose binding lectins from brazilian beans: Dioclea guianensis-DguiL; D. grandiflora-DgL; Cratylia floribunda-CfL; D. violacea-D.vL; D. virgata-DvirL and Canavalia brasiliensis-ConBr. The lectins were injected intravenously (i.v.) into rats (0.1 and 1.0 mg/kg; 30 min before irritants) and its activities compared to E. coli endotoxin (LPS,30 μg/kg i.v.). Three lectins (DvL, CfL and DguiL), although less intense than LPS, inhibited the neutrophil migration induced by carrageenan (Cg, 300 μg) in a dose-dependent manner (0.1 and 1.0 mg/kg). DvL activity was reversed by 0.1 M α-D-methyl-mannoside (α-CH3), but not by 0.1 M α-D-galactose. The fMLP (44 ng)-induced neutrophil migration was also reduced by these lectins. Endotoxin contamination of lectin samples could be excluded since α-CH3 treatment reversed the DvL effect, but did not modify LPS inhibitory activity. Carrageenan (300 μg)-induced paw oedema was also reduced by LPS or lectin treatments. Conversely, none of the tested lectins inhibited dextran (Dex, 300 μg)-induced paw oedema, a classical leukocyte independent model, or zymosan (Zy, 1.0 mg)-induced peritonitis and paw oedema. LPS showed no effect upon Dex-induced paw oedema and barely reduced (25%) the oedematogenic effects of zymosan. As proposed for LPS, the lectin inhibitory activity was better observed on neutrophil-mediated inflammatory reactions. We speculate that the plant lectin antiinflammatory activity is probably due to a competitive blockage of a common leukocyte and/or endothelial selectin carbohydrate ligand.

Serum Concentration and Chemotactic Activity of E-selectin (CD62E) in Inflammatory Bowel Disease

E-selectin (CD62E) is an endothelial specific glycoprotein belonging to the selectin family of adhesion molecules. Because a high expression of this molecule at intestinal mucosal surfaces in inflammatory bowel disease (IBD) has been described earlier, the aim was to assess serum levels of E-selectin (sE-selectin) and to correlate it to disease activity, and further to evaluate its chemotactic properties at physiological concentrations. Levels of sEselectin were measured by a sandwich ELISA technique in 31 IBD patients together with 15 healthy volunteers. In ulcerative colitis the median value was 0.46 nM (0.16–0.75), in Crohn’s disease 0.47 nM (0.22–1.24), and in healthy controls 0.34 nM (0.22–0.83). No statistically significant differences in sE-selectin were revealed between these groups (p > 0.05). The in vitro chemotactic capabilities of E-selectin (in the concentration range of 0.10–31.4 nM) were assessed using the leading front technique. A significantly increased migratory response was found at concentrations of 1.00 (p < 0.05) and 3.14 nM (p < 0.02). It is concluded that sE-selectin in contrast to sICAM-1 does not act as a sensitive indicator of local immune activation in IBD. However, E-selectin may be important for recruitment and accumulation of neutrophilic granulocytes and other phagocytes involved in the inflammatory process seen in IBD. Future investigations are encouraged in order to reveal its in vivo effects.

Angiopoietin-1 and vascular endothelial growth factor regulation of leukocyte adhesion to endothelial cells: role of nuclear receptor-77

OBJECTIVE

Vascular endothelial growth factor (VEGF) promotes leukocyte adhesion to endothelial cells (ECs). Angiopoietin-1 (Ang-1) inhibits this response. Nuclear receptor-77 (Nur77) is a proangiogenic nuclear receptor. In the present study, we assessed the influence of Ang-1 and VEGF on Nur77 expression in ECs, and evaluated its role in Ang-1/VEGF-mediated leukocyte adhesion.

METHODS AND RESULTS

Expression of Nur77 was evaluated with real-time polymerase chain reaction and immunoblotting. Adhesion of leukocytes to ECs was monitored with inverted microscopy. Nur77 expression or activity was inhibited using adenoviruses expressing dominant-negative form of Nur77, retroviruses expressing Nur77 in the antisense direction, and small interfering RNA oligos. Both Ang-1 and VEGF induce Nur77 expression, by >5- and 30-fold, respectively. When combined, Ang-1 potentiates VEGF-induced Nur77 expression. Ang-1 induces Nur77 through the phosphoinositide 3-kinase and extracellular signal-regulated protein kinase 1/2 pathways. VEGF induces Nur77 expression through the protein kinase D/histone deacetylase 7/myocyte enhancer factor 2 and extracellular signal-regulated protein kinase 1/2 pathways. VEGF induces nuclear factor-kappaB transcription factor, vascular cell adhesion molecule-1, and E-selectin expressions, and promotes leukocyte adhesion to ECs. Ang-1 inhibits these responses. This inhibitory effect of Ang-1 disappears when Nur77 expression is disrupted, restoring the inductive effects of VEGF on adhesion molecule expression, and increased leukocyte adhesion to ECs.

CONCLUSIONS

Nur77 promotes anti-inflammatory effects of Ang-1, and functions as a negative feedback inhibitor of VEGF-induced EC activation.

Anti-C1q antibodies have higher correlation with flares of lupus nephritis than other serum markers

OBJECTIVE

Autoantibodies are important in the diagnosis and classification of systemic lupus erythematosus (SLE), but whether they correlate with changes in disease activity within individual patients is controversial. We assessed the association between changes in SLE global and renal activity and changes in several autoantibodies and cell adhesion molecules in patients with SLE.

METHODS

Stored sera collected at two or three clinic visits from each of 49 SLE patients (91% female, 59% African-American, 31% Caucasian, 10% other ethnicity, 38% under 30 years, 41% between 30-44 years, and 21% 45-63 years) were analyzed. The visits were chosen to include one visit with proteinuria, and one or two without, for each patient. Global disease activity was measured by the Physician's Global Assessment (PGA), SELENA-SLEDAI (SLE Disease Activity Index modified to exclude anti-dsDNA and complement) and renal activity assessed by urine protein (by urine dipstick) and Renal Activity Score. Sera were assayed for anti-C1q, anti-chromatin, anti-dsDNA, anti-ribosomal P, monocyte chemotactic protein-1 (MCP-1), vascular cell adhesion molecule (VCAM) intercellular adhesion molecule (ICAM) and complement. The associations between changes in disease activity and changes in biomarker levels were assessed.

RESULTS

In terms of global disease activity, anti-C1q had the highest association with the PGA (p = 0.09) and was strongly associated with modified SELENA-SLEDAI (p = 0.009). In terms of renal activity, anti-C1q had the highest association with proteinuria (p = 0.079), and was strongly associated with Renal Activity Score (p = 0.006).

CONCLUSION

Anti-C1q performed the best of the potential biomarkers, being significantly associated with the modified SELENA-SLEDAI and with the Renal Activity Score. This study indicates the potential superior utility of anti-C1q over anti-dsDNA and other measures to track renal activity.

Isolation and anti-inflammatory activity of colchicinoids from Gloriosa superba seeds

Gloriosa superba L. (Liliaceae) seeds, known as "kalihari" (Hindi), were phytochemically investigated for colchicine (well known for gout treatment) and other related alkaloid content. Colchicine, 2- demethylcolchicine, 3-demethylcolchicine, and N-formyl-N-deacetylcolchicine were alkaloids isolated from the seeds. The isolated samples have been standardized for their purity with respect to the reference standard using HPLC. The structures were confirmed by NMR spectroscopy and were analyzed by spiking them along with colchicine reference by HPLC. The purity of colchicine, 2- demethylcolchicine, 3- demethylcolchicine and N-formyl-N-deacetylcolchicine were 99.82, 96.78, 98.71, and 98.13% respectively. The compounds were subjected to an anti-inflammatory study by using the formaldehyde inflammagen-induced inflammation model. Oral administration of colchicine at 2, 4, and 6 mg/kg body weight resulted in 48.9, 68.7, and 79.1% inhibition respectively, while 30.9% inhibition was seen in the phenylbutazone 100 mg/kg treated group once daily for a period of 4 days. The results clearly indicated that the colchicine is more effective as an anti-inflammatory agent compared with phenylbutazone, the standard drug used in the study, whereas the oral administration of 6 mg/kg body weight of 2- demethylcolchicine, 3-demethylcolchicine and N-formyl-N-deacetylcolchicine showed very poor activity (41.6, 40.4, and 41.1% activity respectively).

Correlation between soluble intercellular adhesion molecule 1 level and extracellular superoxide dismutase activity in rheumatoid arthritis: a possible association with disease activity

OBJECTIVE

We investigated serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and the activity of extracellular superoxide dismutase (EC-SOD) in rheumatoid arthritis (RA). We also considered whether there was a correlation between sICAM-1 and EC-SOD and disease activity.

METHODS

Levels of sICAM-1 were measured in serum from 42 patients with active RA and 30 control subjects by enzyme-linked immunosorbent assay (ELISA). EC-SOD activity was determined in sera isolated from patients with active RA and from controls.

RESULTS

The serum levels of sICAM-1 were significantly higher in patients with RA than in control subjects (p<0.001). In contrast, the activity of EC-SOD was significantly lower in RA patients than in healthy controls (p<0.001). A significant negative correlation was found between the levels of sICAM-1 and EC-SOD activity (r=-0.39, p<0.01). There was a statistically positive correlation between sICAM-1 levels with Ritchie articular index (RAI) score and C-reactive protein (CRP) (r=0.32, p<0.05; r=0.44, p<0.01, respectively).

CONCLUSIONS

These results show that the increased levels of sICAM-1 present in active RA patients might be due to the decreased activity of EC-SOD, and increased levels of sICAM-1 may also reflect disease status or activity.

Crude aqueous extract of the root bark of zanthoxylum xanthoxyloides inhibits white blood cells migration in acute inflammation

BACKGROUND

Crude aqueous extract of Zanthoxylum xanthozyloides is used locally to treat inflammatory conditions. Previous study confirmed that the extract has anti-inflammatory activity and also reduced vascular response in inflammation.

OBJECTIVE

To identify the effect of the extract on migration of white blood cells to the site of inflammation.

METHOD

The extract was obtained by Soxhlet extraction and rotatory evaporation, followed by freeze-drying. Cohorts of Wistar rats (150g - 200g) were randomly assigned to 6 treatment cells, and were given, per os, three different treatments: indomethacin (20mg/kg and 40mg/kg), the extract (2000mg/kg and 4000mg/kg), and 0.9% saline (two groups of control). Inflammation was induced with carrageenin in the hind paw of the treated groups of rats and one group of the control (positive control), one hour after treatment. Inflammatory exudates from the inflamed paws were collected and the white blood cells (WBCs) counted.

RESULTS

Carrageenin increased the total WBC count (in the paw fluid) which was reduced by the extract and indomethacin (p<0.05). Neither the extract nor indomethacin had any effect on total WBC count in the non-carrageenin treated control rats.

CONCLUSION

The extract did not affect the pre-existing WBC population at the site of inflammation but rather inhibited migration of the cells to the site.

Increased anisotropy in neonatal meningitis: an indicator of meningeal inflammation

INTRODUCTION

Increased anisotropy in brain abscesses has been shown to be due to adhesion of inflammatory cells and is suggestive of an active inflammatory process. The objective of this study was to determine if similar changes occur in the pia-arachnoid on the surface of the cerebral cortex in patients with pyogenic meningitis, and if these changes regress following antibiotic therapy.

METHODS

Diffusion tensor imaging (DTI) was performed on 14 term neonates (mean age 13 days) with bacterial meningitis and 10 healthy age- and sex-matched controls. Regions of interest (ROIs) were placed on areas including the leptomeninges, the cerebral cortex and adjoining subcortical white matter for quantitation of mean fractional anisotropy (FA) and diffusivity (MD) values. Follow-up MRI was performed in five of the neonates in the patient group after 2 weeks of antibiotic treatment. FA and MD values were compared in patients before and after antibiotic treatment as well as with those in the healthy controls.

RESULTS

Significantly higher FA values but no difference in MD values were observed in the patient group as compared to the healthy controls at both time points (before and after antibiotic treatment). Significantly decreased FA values in the frontal, occipital and temporal cortical regions were observed in patients following antibiotic treatment.

CONCLUSION

DTI-derived FA may be of value in the noninvasive assessment of meningeal inflammatory activity and treatment response in neonates.

Levels of gingival tissue platelet activating factor after conventional and regenerative periodontal surgery

The hypothesis, a relationship between gingival tissue platelet activating factor (PAF) levels and healing after periodontal surgery, was tested by measuring PAF levels in gingival tissues collected from sites that had undergone flap surgery and guided tissue regeneration (GTR) or flap surgery alone. Using a split-mouth design, 20 intrabony defects were randomly assigned to treatment with flap surgery and GTR (group 1) or with flap surgery alone (group 2). Gingival tissue samples were obtained at surgery (baseline) and at 6-month follow-up evaluation visit. One half of each sample was used for analysis of PAF levels by high-performance liquid chromatography, and the other half of the sample was used for histomorphometric analysis that included measurements of number and diameter of blood vessels. PAF levels and diameter of blood vessels were significantly decreased (p < 0.01), and the number of blood vessels was significantly increased (p < 0.05) in both groups after 6 months compared to the baseline values. Postoperative number of blood vessels were significantly higher in group 1 (p < 0.05), whereas there was no significant difference in postoperative PAF levels between the two groups (p > 0.05). Based on the reported results, it is suggested that a decrease in gingival PAF levels might be found after conventional and regenerative periodontal surgery.

Correlation between the Serum Values of Soluble Intercellular Adhesion Molecule-1 and Total Sialic Acid Levels in Patients with Breast Cancer

BACKGROUND

In this study, we aimed to investigate serum total sialic acid (TSA) and soluble intracellular adhesion molecule-1 (sICAM-1) levels in breast cancer patients to find a correlation with the cancer stage.

METHODS

The parameters from sera of 61 patients with breast cancer were measured. The concentrations of serum sICAM-1 and TSA were measured in serum samples from 61 patients with breast cancer and 25 healthy control subjects using enzyme-linked immunoassay and thiobarbituric acid method.

RESULTS

Mean serum sICAM-1 and TSA levels were significantly higher in the total patient group than in the control group (p < 0.001). Thus, the correlation between TSA and sICAM-1 became more significant in metastatic breast cancer. There were significant positive correlations between TSA and sICAM-1 in stage I+II (r = 0.59, p < 0.05), stage III (r = 0.47, p < 0.05), and stage IV (r = 0.89, p < 0.01), and total patient group (r = 0.56, p < 0.001).

CONCLUSION

SerumsICAM-1 and TSA levels were higher in patients with breast cancer, than that of the control group, and also in the metastatic breast cancer group. Significant correlations between serum sICAM-1 and TSA may reflect the similar function of these molecules as adhesion molecules, and their roles in the carcinogenesis of breast cancer as well as metastasis.

Flow cytometrical analysis of adhesion molecules, T-lymphocyte subpopulations and inflammatory markers in pterygium

BACKGROUND/AIM

Pterygium is a relatively frequent ocular surface disease with an unexplained etiopathogenesis. Our study was carried out with the aim to identify the presence of inflammatory cells and mediators such as T-lymphocyte subgroups (CD4 and CD8), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and human leukocyte antigen-DR (HLA-DR) in pterygium tissue.

METHODS

Pterygium tissue, obtained from 24 patients, and normal conjunctival tissue, from the nasal bulbar conjunctiva obtained from 14 patients operated for ocular perforations or vitrectomy, were separated into epithelial and stromal components under the microscope and suspended with phosphate-buffered saline solution to form a suspension. Cell suspensions were treated with specific antibodies for ICAM-1, VCAM-1, and HLA-DR and T-lymphocyte subgroups and evaluated with flow cytometry. The obtained data were compared statistically.

RESULTS

When compared to the control tissue samples, higher rates of ICAM-1-positive cells, VCAM-1-positive cells and HLA-DR-positive cells were recorded in pterygium tissue samples. CD4 and CD8 lymphocytes were also found to be at higher levels when compared to the control group. There was a statistically significant difference between the two groups.

CONCLUSION

When compared with normal conjunctival tissue, pterygium tissue had increased levels of T-lymphocyte infiltration and inflammatory markers demonstrating the possible contribution of cellular immunity to the pathogenesis.

Mooren Ulcer

PURPOSE

To determine the pattern and distribution of mononuclear cells, adhesion, and co-stimulatory molecules in the conjunctiva of patients with Mooren ulcer.

METHODS

Conjunctival biopsy specimens were obtained from 6 patients with Mooren ulcer and 6 healthy individuals. Immunohistochemistry was performed on frozen sections of the cryopreserved human conjunctivas using monoclonal antibodies directed against CD1alpha, CD3, CD4, CD8, CD20, CD25, CD57, and CD68 cells; the adhesion molecules E-selectin, vascular cell adhesion molecule-1 (VCAM-1), very late activation-4 (VLA-4), ICAM-1, and LFA-1; and the co-stimulatory molecules CD28, B7-1, B7-2, and CTLA-4.

RESULTS

Differences in expression on the conjunctival epithelium from patients with Mooren ulcer and normal subjects were noted only for VCAM-1, VLA-4, ICAM-1, and LFA-1. The ratio of CD4+/CD8+ cells in Mooren ulcer specimens was significantly higher (3.5-fold). However, in the substantia propria, Mooren ulcer specimens revealed significantly increased numbers of CD1alpha+, CD3+, CD4+, CD20+, CD28+, B7-1+, B7-2+, and CD68+ cells. The ratios of CD4+/CD8+ cells and B7-2+/antigen-presenting cells in Mooren ulcer specimens were significantly higher (5-fold). All tested adhesion molecules showed significant up-regulation in the patients' conjunctivas. Mooren ulcer vascular endothelial cells prominently expressed E-selectin, VCAM-1, VLA-4, and ICAM-1 compared with normal conjunctiva.

CONCLUSION

The simultaneous presence of multiple types of inflammatory cells, adhesion, and co-stimulatory molecules in Mooren ulcer conjunctiva suggests that their interaction may contribute to a sustained immune activation as at least part of the pathogenic mechanism of this disorder.

Cell populations and adhesion molecules expression in conjunctiva before and after bone marrow transplantation

We were interested to analyse the composition of the cellular infiltrate and adhesion molecules expression in the conjunctiva before and at least one hundred days after autologous and allogenic bone marrow transplantation (BMT) and its relation with the presence of dry eye. We used immunohistochemistry on cryopreserved human conjunctiva with monoclonal antibodies to T-lymphocytes (CD3, CD4 and CD8), B-lymphocytes (CD19), macrophages (CD14), natural killer cells (NK, CD57), intercellular adhesion molecule 1 (ICAM-1), E-selectin, vascular cell adhesion molecule-1 (VCAM-1), lymphocyte function associated antigen-1 (LFA-1), very late antigen-4 (VLA-4), interleukin 2 receptor (IL2r, CD25) and HLA-DR. Our autologous recipients had no graft-versus-host disease (GVHD) but allogenic patients had chronic GVHD. After autologous BMT the conjunctiva had significantly more: (1) T lymphocytes (CD3+, CD4+, CD8+) in the epithelium; (2) CD4+ and CD14+ cells in the stroma; and (3) VLA-4 expression in the stroma than before BMT. After allogenic BMT, the conjunctiva exhibited a significant increase of: (1) CD3+ and CD14+ cells in the epithelium; (2) T lymphocytes (CD3+, CD4+, CD8+) and CD14+ cells in the stroma; and (3) VLA-4 and LFA-1 expression in the stroma than before BMT. After the engraftment, the comparison between autologous and allogenic recipients revealed that: (1) there were no significant differences in adhesion molecule expression; (2) the epithelium of autologous recipients had significantly more CD3+ cells; and (3) the stroma of allogenic patients had significantly more CD3+ and CD8+ cells. Among allogenic recipients, CD14+ cells were significantly increased both in the epithelium and in the stroma of patients with signs or symptoms of dry eye in comparison with patients without ocular involvement. Additionally, those having keratoconjunctivitis sicca (KCS) had CD4/CD8 ratios significantly higher than those without KCS. In conclusion, in the conjunctiva after autologous BMT a subclinical cell mediated immune reaction seems to take place. The conjunctivitis of chronic GVHD is complex, with T cells and macrophages dramatically contributing to the process.

Helianthus tuberosus agglutinin directly induces neutrophil migration, which can be modulated/inhibited by resident mast cells

We investigated the effect of Helianthus tuberosus agglutinin (HTA) on neutrophil migration in vivo and in vitro. The role of resident cells in this effect was analyzed. Peritonitis was induced by injecting stimuli into rat (150–200 g) peritoneal cavities, and in vitro neutrophil chemotaxis was performed using a Boyden microchamber. HTA (80, 200, or 500 µg/mL per cavity) induced significant in vivo neutrophil migration (p < 0.05); in vitro assays showed that this lectin also induced neutrophil chemotaxis, an effect inhibited by the incubation of lectin associated with α-D(+)-mannose, its specific binding sugar. Depletion of the resident-cell population by peritoneal lavage did not alter HTA-induced neutrophil migration (200 µg/mL per cavity). The opposite strategy, increasing peritoneal macrophages by intraperitoneally injecting rats with thioglycollate, did not enhance the neutrophil migration produced by HTA (200 µg/mL per cavity). In addition, injection of supernatant from HTA-stimulated macrophage culture (300 µg/mL) into rat peritoneal cavities did not induce neutrophil migration. However, reduction of the peritoneal mast-cell population potentiated the neutrophil migration (p < 0.05) induced by HTA (200 µg/mL per cavity). Lectin from H. tuberosus has a direct neutrophil chemotatic effect that is modulated by mast cells.Key words: lectins, inflammation, Helianthus tuberosus, neutrophil migration.

Resveratrol as an anti-inflammatory and anti-aging agent: mechanisms and clinical implications

Resveratrol is a phytoalexin polyphenolic compound found in various plants, including grapes, berries, and peanuts. Multiple lines of compelling evidence indicate its beneficial effects on neurological, hepatic, and cardiovascular systems. Also one of the most striking biological activities of resveratrol soundly investigated during the late years has been its cancer-chemopreventive potential. In fact, recently it has been demonstrated that this stilbene blocks the multistep process of carcinogenesis at various stages: tumor initiation, promotion, and progression. One of the possible mechanisms for its biological activities involves downregulation of the inflammatory response through inhibition of synthesis and release of pro-inflammatory mediators, modification of eicosanoid synthesis, inhibition of activated immune cells, or inhibiting such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) via its inhibitory effects on nuclear factor (kappa)B (NF-(kappa)B) or the activator protein-1 (AP-1). More recent data provide interesting insights into the effect of this compound on the lifespan of yeast and flies, implicating the potential of resveratrol as an anti-aging agent in treating age-related human diseases. It is worthy to note that the phenolic compound possesses a low bioavailability and rapid clearance from the plasma. As the positive effects of resveratrol on inflammatory response regulation may comprise relevant clinical implications, the purpose of this article is to review its strong anti-inflammatory activity and the plausible mechanisms of these effects. Also, this review is intended to provide the reader an up-date of the bioavailability and pharmacokinetics of resveratrol and its impact on lifespan.

Pro-inflammatory effect of Arum maculatum lectin and role of resident cells

Arum maculatum agglutinin (AMA) is a monocot lectin isolated from tubers of Arum maculatum L. (Araceae) which exhibits different specificity towards oligo-mannosidic-type and N-acetyllactosaminic-type glycans. We have investigated the effect of this lectin on the cells of the immune system. Models of neutrophil migration in vivo, neutrophil chemotaxis in vitro and macrophage cultures were used to study the lectin inflammatory activity. When administered into rat peritoneal cavities, AMA (80, 200 and 500 microg/mL/cavity) induced significant and dose-dependent neutrophil migration. This effect was inhibited by incubation with alpha-methyl-d-mannoside. A 83% depletion in the number of resident cells following peritoneal lavage did not reduce the AMA-induced neutrophil migration, as compared to sham animals (not washed). However, pre-treatment with 3% thioglycolate which increases the peritoneal macrophage population by 236%, enhanced the neutrophil migration induced by AMA (200 microg/mL/cavity) (119%, p < 0.05). Reduction of peritoneal mast cell population by chronic treatment of cavities with compound 48/80 did not modify AMA-induced neutrophil migration. The neutrophil chemotaxy assay in vitro shows that the lectin (300 microg/mL) induces neutrophil chemotaxy (368% p < 0.05) compared to RPMI. Finally, injection into peritoneal cavities of supernatants from macrophage cultures obtained after stimulation with AMA (300 microg/mL) enhanced neutrophil migration (110% p < 0.05). Summarizing, our data suggest that A. maculatum agglutinin presents pro-inflammatory activity, inducing neutrophil migration by two ways, one which is independent on resident cells and another one dependent on the presence of these cells.

Mechanism by which H-2g, a glucose analog of blood group H antigen, mediates angiogenesis

The 4A11 antigen is a unique cytokine-inducible antigen up-regulated on rheumatoid arthritis (RA) synovial endothelial cells (ECs) compared with normal ECs. Previously, we showed that in soluble form, this antigen, Lewis(y)-6/H-5-2 (Le(y)/H) or its glucose analog, 2-fucosyl lactose (H-2g), induced the expression of EC intercellular adhesion molecule-1 (ICAM-1) and leukocyte-endothelial adhesion through the Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) pathway. Currently, we show that H-2g induces release of EC angiogenic basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), an effect inhibited by decoy nuclear factor kappaB (NFkappaB) oligodeoxynucleotide (ODN). JAK2 and phosphoinositide-3 kinase (PI3K) are 2 upstream kinases of NFkappaB activated by H-2g, as confirmed by an inhibitor of kappa B kinase (IKKbeta) assay. In vitro, H-2g induces vascular sprouting in the rat aortic ring model, whereas blockade of JAK2, PI3K, or NFkappaB inhibits sprouting. Likewise, in the in vivo mouse Matrigel plug angiogenesis assay, chemical inhibitors and antisense or decoy ODNs of JAK2, PI3K, or NFkappaB decrease angiogenesis, confirming the importance of these pathways in H-2g-induced EC signaling. The critical role of Le(y)/H involvement in angiogenesis and its signaling pathways may provide new targets for therapy of diseases characterized by pathologic neovascularization.

Levels of soluble E-selectin in patients with active Behcet's disease

Behcet's disease is a systemic vasculitis of unknown aetiology. Endothelial cell injury plays an important role in the pathogenesis and immunopathology of Behcet's disease. E-selectin is expressed by activated endothelial cells. Because the selectin adhesion molecules are shed from activated cells, soluble forms of these proteins can be used as activation markers of endothelium (E-selectin). The pathogenesis of Behcet's disease (BD) is closely related to endothelial cells, leucocyte functions and immunity. The aim of this study was to investigate circulating E-selectin adhesion molecules, which are known to play a significant part in the immune response especially by regulating interaction of the leucocytes with endothelium in BD. Plasma E-selectin concentrations were evaluated in 23 patients with BD and 20 healthy control subjects. The disease activity was evaluated by clinical manifestations (oral aphthous ulcer, genital ulceration, positive pathergy test, skin lesions, eye involvement, thrombophlebitis and arthritis) and by laboratory investigations [erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)]. The patients were newly or previously diagnosed cases not taking any drug for BD. Levels of E-selectin were measured with commercially available sandwich enzyme-linked immunosorbent assay (ELISA) kits using human sE-selectin (cat. no: BMS 205). Plasma E-selectin concentrations of patients and controls were compared with the Mann-Whitney U test. Statistical significance was assigned to p values lower than 0.05. Serum levels (mean+/-SD) of soluble E-selectin (sE-selectin) were significantly higher in 23 patients with BD than in 20 healthy controls (53.2+/-18.2 ng/ml vs 33.8+/-7.5 ng/ml, p<0.0001). A statistically significant positive correlation was observed between sE-selectin levels and CRP and ESR in patients with BD (r=0.78, p<0.001 and r=0.56, p<0.01, respectively). Increases in the E-selectin in BD may be a direct consequence of the leucocyte and endothelium activations observed during the disease process. The noninvasive investigations can be used as biochemical markers for inflammation. This may provide additional information regarding disease activity along with the traditional indices such as ESR and CRP.

Neutrophil Adhesion Molecule Expression in Familial Mediterranean Fever: Discordance between the Intravascular Regulation of β2 Integrin and L-Selectin Expression in Acute Attack

Background

To determine the surface expression of neutrophil β2 integrin (CD11b/CD18) and L-selectin (LS) adhesion molecules in patients with familial Mediterranean fever (FMF) and to investigate the in vitro regulation of their expression in response to chemoattractant stimuli.

Methods

Neutrophil surface expression of CD11b and LS molecules was analyzed by flow cytometry in anticoagulated whole blood drawn from FMF patients and normal controls, and the in vitro regulation of these molecules induced by the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (FMLP) was assayed.

Results

Patients during acute FMF attacks showed a statistically significant increased neutrophil surface CD11b compared with normal controls (mean fluorescence intensity: 22.8 ± 13.7 vs 12.8 ± 10.41, respectively; p = .03). There was no difference in LS expression between the groups. Neutrophils of FMF patients regulate CD11b and LS expression induced by chemoattractant (FMLP) stimulation to a degree similar to that in controls. Conclusions: β2 Integrin is up-regulated during an acute attack of FMF in dissociation with LS expression, suggesting a unique nonchemoattractant-mediated neutrophil activation.

Inhibitory effects of bucillamine on the expression of vascular cell adhesion molecule-1 in human umbilical vein endothelial cells

Bucillamine (BUC) has been found to have beneficial effects in the treatment of rheumatoid arthritis (RA), in which the activation of endothelial cells plays an important role in the pathogenesis. The current studies examined the effect of BUC and its intramolecular disulfide form (BUC-ID) on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVEC) stimulated with tumor necrosis factor-alpha (TNF-alpha). HUVEC (4 x 10(4)/well) were incubated with medium M199 containing heparin and 20% FCS with endothelial cell growth supplement (ECGS) for 24 h in the presence or absence of BUC or BUC-ID, after which the culture medium was replaced with ECGS free medium. Then the cultures were further carried out for additional 24 h with TNF-alpha (10 ng/ml) in the presence or absence of BUC or BUC-ID. BUC-ID, but not BUC, appeared to suppress the expression of VCAM-1 on HUVEC stimulated with TNF-alpha in a dose-response manner at its pharmacologically relevant concentrations (0.3-3.0 microg/ml), whereas only the 3 microg/ml concentration level of BUC-ID had a statistically significant effect, although the effect was relatively small. By contrast, lower concentrations of BUC-ID (1-3 microg/ml) suppressed the secretion of soluble VCAM-1 by HUVEC much more effectively. Of note, at the concentration of 3 microg/ml neither BUC nor BUC-ID significantly influenced the expression of ICAM-1 and E-selectin on TNF-alpha stimulated HUVEC. These results indicate that BUC-ID, but not BUC, specifically downregulates the surface expression of VCAM-1 as well as the release of soluble VCAM-1 by HUVEC stimulated with TNF-alpha. BUC-ID suppressed the production of solubleVCAM-1 by RA bone marrow CD34+ cells stimulated with SCF, GM-CSF and TNF-alpha more effectively than BUC. The data thus suggest that one of the mechanisms of action of BUC involves the inhibition of the activation of endothelial cells.

Adrenomedullin reduces VEGF-induced endothelial adhesion molecules and adhesiveness through a phosphatidylinositol 3'-kinase pathway

OBJECTIVE

In the initial phase of inflammation, vascular endothelial growth factor (VEGF) can act as a proinflammatory cytokine by inducing adhesion molecules that bind leukocytes to endothelial cells. Adrenomedullin (AM) is known to act as either a proinflammatory or an anti-inflammatory agent. In this study, we examined the effects of AM on adhesion molecule expression and leukocyte adhesiveness in VEGF-stimulated human umbilical vein endothelial cells.

METHODS AND RESULTS

When stimulated with VEGF, the mRNAs of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin were dose-dependently upregulated. AM inhibited the VEGF-induced protein and mRNA expression of ICAM-1, VCAM-1, and E-selectin. Phosphatidylinositol 3'-kinase inhibitor and a dominant-negative form of Akt significantly inhibited the suppressive effect of AM on VEGF-induced adhesion molecule expression. Thus, AM inhibits VEGF-stimulated ICAM-1 and VCAM-1 expression through a phosphatidylinositol 3'-kinase/Akt pathway. AM reduced VEGF-induced endothelial adhesiveness for leukocytes.

CONCLUSIONS

These results suggest that AM might have an anti-inflammatory role in controlling VEGF-induced adhesion molecule gene expression and adhesiveness toward leukocytes in endothelial cells.

Functional alterations in CD11b(+)Gr-1(+) cells in mice injected with allogeneic tumor cells and treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure results in an increased percentage of CD11b(+) (Mac-1(+)) cells in the spleens of mice challenged with P815 tumor cells, coincident with a failure of the mice to generate allospecific CD8(+) CTL activity. Since CD11b(+)Gr-1(+) myeloid suppressor cells (MSC) have been described as that which prevent cytotoxic T lymphocyte (CTL) development in a variety of disease states, we hypothesized that TCDD promoted MSC development, leading to suppression of CTL activity. The purpose of the present studies was to compare the phenotypic and functional characteristics of CD11b(+) cells in vehicle- and TCDD-treated mice during the P815 tumor allograft response to determine their potential to function as MSC. Initial studies showed that virtually all splenic CD11b(+) cells in both vehicle- and TCDD-treated mice co-expressed Gr-1. Consistent with MSC activity, CD11b(+)Gr-1(+) cells isolated from TCDD- but not vehicle-treated mice suppressed the development of CTL activity when added in vitro to mixed lymphocyte-P815 tumor cell cultures. Also consistent with MSC activity, this suppressive effect in vitro required cell-to-cell contact. Surprisingly, however, in vivo depletion of CD11b(+)Gr-1(+) cells failed to affect TCDD-induced suppression of the CTL response, arguing against an immunoregulatory role for the cells in vivo. Immunohistochemical analysis of the spleen showed that CD11b(+)Gr-1(+) cells were localized in the red pulp, and physically separated from the T cells in the white pulp. The localization of CD11b(+)Gr-1(+) cells in the red pulp was indicative of extramedullary myelopoiesis and suggested that TCDD enhanced myelopoiesis. A significantly enhanced neutrophilia in the blood of TCDD-treated mice supported this conclusion. CD11b(+)Gr-1(+) cells isolated from the blood or spleen of TCDD-treated mice produced up to fivefold higher levels of superoxide following PMA stimulation when compared with cells from vehicle-treated mice. However, unlike vehicle-treated mice, CD11b(+)Gr-1(+) cells from TCDD-treated mice were unable to kill YAC-1 target cells. These results indicate that TCDD exposure alters the host response to allogeneic tumor growth, resulting in enhanced myelopoiesis perhaps as a compensatory response to the suppressed T cell-mediated immunity in the face of an increasing P815 tumor burden. Furthermore, within the context of the P815 response, TCDD appears to alter the functional capabilities of mature neutrophils, by enhancing their oxidative burst capacity but reducing their tumoricidal response.

Expression of ICAM-1, VCAM-1, E-selectin and TNF-alpha on the endothelium of femoral and iliac arteries in thromboangiitis obliterans

Immunohistochemical light and electron microscopical analysis of surgical biopsies obtained from femoral and iliac arteries of patients with thromboangiitis obliterans (TAO) were performed to investigate the presence of tumour necrosis factor-alpha (TNF-alpha) and expression of the endothelial cell adhesion molecules intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. Expression of ICAM-1, VCAM-1 and E-selectin was increased on endothelium and some inflammatory cells in the thickened intima in all TAO patients. Ultrastructural immunohistochemistry revealed contacts between mononuclear blood cells and ICAM-1-, and E-selectin-positive endothelial cells. These endothelial cells showed morphological signs of activation. The present data indicate that endothelial cells are activated in TAO and that vascular lesions are associated with TNF-alpha secretion by tissue-infiltrating inflammatory cells, ICAM-1-, VCAM-1- and E-selectin expression on endothelial cells and leukocyte adhesion via their ligands. The preferential expression of inducible adhesion molecules in microvessels and mononuclear inflammatory cells suggests that angiogenesis contributes to the persistence of the inflammatory process in TAO.

Adhesion of dendritic cells derived from CD34+ progenitors to resting human dermal microvascular endothelial cells is down-regulated upon maturation and partially depends on CD11a-CD18, CD11b-CD18 and CD36

DC are sentinels of the immune system. In order to reach the skin, bone-marrow-derived DC precursors need to bind and migrate through microvascular endothelial cells. Binding of DC toprimary endothelial cells of the skin has not been investigated. We therefore determined adhesion of DC at different stages of development to human dermal microvascular endothelial cells (HDMEC). DC were derived from CD34+ progenitors in cord blood. To enhance DC maturation, a defined cocktail of IL-1beta+IL-6+TNF-alpha+PGE2 was applied. Adhesion was quantified by fluorimetric and phase-contrast microscopical assays. Significantly more DC precursors (tested on day 5 after isolation) than mature DC (spontaneously matured or cytokine-cocktail-matured and tested on day 13) bound to unstimulated HDMEC. In contrast, the maturation stage of DC had no influence on their binding to human umbilical vein endothelial cells. Pretreatment of HDMEC with TNF-alpha and IFN-gamma resulted in an enhanced attachment of both DC precursors and mature DC. Mature DC lacked expression of CD31, CD36, CD45RA and CLA, and expressed lower levels of CD11a, CD11b and CD49d as compared with precursors tested on day 5. mAb against CD18, CD11a, CD11b, and CD36 markedly inhibited DC binding, whereas anti-CLA, anti-DC-SIGN, anti-CD29 and anti-CD49 mAb did not. Our data support the hypothesis of immunosurveillance with selective recruitment of blood DC precursors to resting and, more so, to inflamed skin. The data have potential relevance for anti-cancer immunotherapy strategies favoring the intracutaneous application of mature DC.

Chronic heart failure and the immune system

Several lines of evidence support a role of immune mechanisms in the pathogenesis of chronic heart failure (CHF). Proinflammatory cytokines (interleukin-1, -2, -6, and tumor necrosis factor) and chemokines are involved in cardiac depression and in the progression of heart failure. Other components believed to be relevant to the pathogenesis of CHF are adhesion molecules, autoantibodies, nitric oxide (NO), and endothelin-1. The origin of the immune activation in patients with CHF is still unknown, however two hypotheses have been proposed on the basis of experimental and clinical data. One suggests that the bowel wall edema leads to bacterial translocation with subsequent endotoxin release and immune activation. The second suggests that the heart in CHF is the main source of cytokines, as is shown by the fact that TNF alpha is produced by the failing myocardium but not by a normal one. No single source of cytokine production (gut or heart) seems sufficient to fully explain the multiple organ involvement and the systemic inflammation of CHF, which is probably related to systemic hypoxia, a potent stimulus for activation of the immune system and for cytokine production. The effort of define the immune system's role has opened new perspectives of therapeutic strategies, such as anti-cytokine drugs, to treat CHF.