Adhesion molecules and their role in inflammation

Gene Set Enrichment Analysis Detected Immune Cell-Related Pathways Associated with Primary Sclerosing Cholangitis

Aim

To explore various immune cell-related causal pathways for primary sclerosing cholangitis (PSC).

Methods

Immune cell-related pathway association study was conducted via integrative analysis of PSC GWAS summary and five immune cell-related eQTL datasets. The GWAS summary data of PSC was driven from 4,796 PSC cases and 19,955 healthy controls. The eQTL datasets of CD4+ T cells, CD8+ T cells, B cells, natural killer cells (NK), monocytes, and peripheral blood cells (PB) were collected from recently eQTL study. The PSC GWAS summary dataset was first aligned with eQTL datasets of six blood cells to obtain the GWAS summary data at overlapped eQTL loci, separately. For each type of cell, the obtained PSC GWAS summary dataset of eQTLs was subjected to pathway enrichment analysis. 853 biological pathways from Kyoto Encyclopedia of Genes and Genomes, BioCarta, and Reactome pathway databases were analyzed.

Results

We identified 36 pathways for B cells, 33 pathways for CD4+ T cells, 28 pathways for CD8+ T cells, 33 pathways for monocytes (MN), 35 pathways for NK cells, and 33 for PB cells (all empirical P values <5.0 × 10-5). Comparing the pathway analysis results detected 25 pathways shared by five immune cells, such as KEGG_CELL_ADHESION_MOLECULES_CAMS (P value <5.0 × 10-5) and REACTOME_MHC_CLASS_II_ANTIGEN_ PRESENTATION (P value <5.0 × 10-5). Several cell-specific pathways were also identified, including BIOCARTA_INFLAM_PATHWAY (P value <5 × 10-5) for B cell.

Conclusion

Our study holds potential to identify novel candidate causal pathways and provides clues for revealing the complex genetic mechanism of PSC.

Serum Inflammation Markers in Tuberculosis

Tuberculosis remains one of the leading infectious cause of death in the world. The goals of screening are to detect active tuberculosis early enough and to identify individuals eligible for preventive therapy to reduce a po tential co-infection by tuberculosis. Plasma/serum screening for selected potential biomarkers could represent a suitable method of tuberculosis diagnosis and treatment outcome. Furthermore, monitoring of tuberculosis treatment is crucial to clinical decision-making and besides the plasmatic concentration of administered antituberculosis drugs, the biomarkers appear to play a significant role in the estimation of the real therapeutical impact.

The current standard remains focused on culture conversion, especially two-month culture status, which has a relatively low sensitivity. Identification of non-sputum-based biomarkers of the treatment respond would be beneficial for individual monitoring of tuberculosis patients.

This mini-review describes several serological/plasmatic markers that can be analyzed by simple immunoassays as ELISA method, e.g. C-reactive protein, soluble intercellular adhesion molecule-1, soluble urokinase plasminogen activator receptor, soluble lymphocyte activation gene-3, granzyme B and soluble tumor necrosis factor receptor one and two as reliable enough as an indicator of successful treatment of tuberculosis.

Bergenin-activated SIRT1 inhibits TNF-α-induced proinflammatory response by blocking the NF-κB signaling pathway

BACKGROUND

Bergenin, a type of polyphenol compound, exhibits antiulcerogenic, anti-inflammatory, antitussive, and burn wound-healing properties. However, its therapeutic effect on tumor necrosis factor α (TNF-α)-induced proinflammatory responses in the airway and potential mechanisms of actions are still unclear. This study aimed to investigate the anti-inflammatory effects and mechanism of bergenin in TNF-α-stimulated human bronchial epithelial (16-HBE) cells.

METHODS

Cell Counting Kit-8 was used to evaluate cytotoxicity. Cytokine expression was analyzed by reverse transcription-quantitative PCR (RT-qPCR) and enzyme-linked immunosorbent assay. Immunofluorescence, western blot, and sirtuin-1 (SIRT1) activity assays were employed to investigate potential molecular mechanisms.

RESULTS

Bergenin obviously decreased both mRNA and protein expression levels of interleukins 6 and 8 (IL-6 and IL-8) in TNF-α-stimulated 16-HBE cells. Bergenin blocked TNF-α-mediated activation of nuclear factor κB (NF-κB) signaling and NF-κB nuclear translocation. Interestingly, RT-qPCR and western blotting results revealed that bergenin did not affect SIRT1 expression, but significantly increased its activity. Bergenin-mediated SIRT1 activation was further confirmed by results indicating decreased acetylation levels of NF-κB-p65 and p53. Moreover, the inhibitory effects of bergenin on mRNA and protein expression levels of IL-6 and IL-8 were reversed by a SIRT1 inhibitor. In addition, combining bergenin and dexamethasone (DEX) yielded additive effects on the reduction of IL-6 and IL-8 expression.

CONCLUSIONS

These findings demonstrate that bergenin could suppress TNF-α-induced proinflammatory responses by augmenting SIRT1 activity to block the NF-κB signaling pathway, which may provide beneficial effects for the treatment of airway inflammation associated with asthma.

An underestimated pathogen: Staphylococcus epidermidis induces pro-inflammatory responses in human alveolar epithelial cells

OBJECTIVES

Conventionally regarded as a harmless skin commensal, Staphylococcus epidermidis accounts for the majority of neonatal late-onset sepsis and is shown to be associated with neonatal inflammatory morbidities, especially bronchopulmonary dysplasia. This study addressed the pro-inflammatory capacity of different S. epidermidis strains on human alveolar epithelial cells.

METHODS

A549 cell monolayers were stimulated by live bacteria of S. epidermidis RP62A strain (biofilm-positive) and ATCC 12228 strain (biofilm-negative) at a multiplicity of infection ratio of 10 for 24 h. LPS (100 ng/ml) and Pam3CSK4 (1 µg/ml) were used for comparisons. Cell viability was measured by MTT method. The mRNA and protein expression of inflammatory mediators and toll-like receptor (TLR)-2 were assessed using RT-PCR, immunoassays and immunofluorescence.

RESULTS

Both S. epidermidis strains induced expression of tumor necrosis factor (TNF)-α, IL-1β, interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1, interferon γ-induced protein 10 (IP-10) and intercellular adhesion molecule (ICAM)-1, but not IL-10. The stimulatory effect of RP62A exceeded that of LPS (p < 0.05). RP62A strain showed a trend towards higher induction of pro-inflammatory mediators than ATCC 12228 strain. The co-stimulation with RP62A strain decreased cell viability compared to control and TLR agonists (p < 0.05). RP62A but not ATCC 12228 stimulated mRNA and protein expression of TLR2.

CONCLUSIONS

S. epidermidis drives pro-inflammatory responses in lung epithelial cells in vitro. The pro-inflammatory capacity of S. epidermidis may differ between strains. Biofilm-positive S. epidermidis strain seems to induce more potent pulmonary pro-inflammation than biofilm-negative S. epidermidis strain.

Ureaplasma isolates differentially modulate growth factors and cell adhesion molecules in human neonatal and adult monocytes

Generally regarded as commensal bacteria, the pathogenicity of Ureaplasma has often been considered low. Controversy remains concerning the clinical relevance of Ureaplasma infection in the pathogenesis of inflammation-related morbidities. Recently, we demonstrated Ureaplasma-driven pro-inflammatory cytokine responses in human monocytes in vitro. We hypothesized that Ureaplasma may induce further inflammatory mediators. Using qRT-PCR and multi-analyte immunoassay, we assessed the expression of granulocyte-colony stimulating factor (G-CSF), vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in term neonatal and adult monocytes exposed to Ureaplasma urealyticum serovar 8 (Uu8) and U. parvum serovar 3 (Up3). Ureaplasma significantly induced VEGF mRNA in neonatal (Up3: p < 0.05, versus broth control) and adult monocytes (Uu8: p < 0.05) as well as ICAM-1 mRNA in neonatal cells (p < 0.05 each). As far as protein expression was concerned, Up3 stimulated VEGF release in both monocyte subsets (p < 0.01) and enhanced secretion of ICAM-1 protein in neonatal monocytes (p < 0.05). In adult cells, ICAM-1 protein release was increased upon exposure to both isolates (Uu8: p < 0.05, Up3: p < 0.01). Ureaplasma-induced responses did not significantly differ from corresponding levels mediated by E. coli lipopolysaccharide (LPS). The stimulatory effects were dose-dependent. Ureaplasma infection, on the contrary, did not affect G-CSF and VCAM-1 expression. Of note, co-infection of LPS-primed neonatal monocytes with Ureaplasma enhanced LPS-induced ICAM-1 release (Uu8: p < 0.05). Our results confirm Ureaplasma-driven pro-inflammatory activation of human monocytes in vitro, demonstrating a differential modulation of growth factors and cell adhesion molecules, that might promote unbalanced monocyte responses and adverse immunomodulation.

Differential expression of adhesion molecules by sinonasal fibroblasts among control and chronic rhinosinusitis patients

BACKGROUND

Chronic rhinosinusitis (CRS) is characterized by inflammatory cell migration into sinus tissue with resultant inflammation fueled by a milieu of cytokines. Fibroblasts may contribute to inflammation through expression of leukocyte adhesion molecules such as vascular cell adhesion molecule (VCAM) and intercellular adhesion molecule (ICAM). VCAM attracts eosinophils and mast cells contributing to Th2 skewing, and ICAM attracts neutrophils and to a lesser degree, eosinophils, and contributes to mixed Th1/Th2 skewing. The purpose of this study was to compare sinus fibroblast adhesion molecule expression ex vivo among CRS subtypes and in vitro after cytokine stimulation.

METHODS

Sinus biopsy specimens were taken from control patients (n = 13), CRS without nasal polyposis (CRSsNP, n = 6), and CRS with nasal polyposis (CRSwNP, n = 15). ex vivo levels of VCAM and ICAM were measured by flow cytometry from single cell suspensions of tissue biopsy specimens. Changes in VCAM and ICAM expression to cytokine exposure were assessed using in vitro cultured sinonasal fibroblasts treated with tumor necrosis factor (TNF)-α, interleukin (IL)-4, or interferon (IFN)-γ.

RESULTS

ex vivo VCAM expression was lowest in controls, higher in CRSsNP, and highest in CRSwNP. in vitro stimulation with TNF-α and IL-4, but not IFN-γ, increased VCAM among CRSsNP, while expression in CRSwNP remained elevated with all treatments except IFN-γ. ex vivo ICAM expression was elevated in both CRS subtypes. in vitro stimulation with TNF-α and IFN-γ, but not IL-4, increased ICAM expression in all patients with the largest effects among the CRSsNP subgroup.

CONCLUSION

Sinonasal fibroblast expression of adhesion molecules in sinusitis varies by disease state and is selectively influenced by exposure to inflammatory cytokines.

Integrative genomic analysis identifies a role for intercellular adhesion molecule 1 in childhood asthma

BACKGROUND

Childhood asthma is characterized by chronic airway inflammation. Integrative genomic analysis of airway inflammation on genetic and protein level may help to unravel mechanisms of childhood asthma. We aimed to employ an integrative genomic approach investigating inflammation markers on DNA, mRNA, and protein level at preschool age in relationship to asthma development.

METHODS

In a prospective study, 252 preschool children (202 recurrent wheezers, 50 controls) from the Asthma DEtection and Monitoring (ADEM) study were followed until the age of six. Genetic variants, mRNA expression in peripheral blood mononuclear cells, and protein levels in exhaled breath condensate for intercellular adhesion molecule 1 (ICAM1), interleukin (IL)4, IL8, IL10, IL13, and tumor necrosis factor α were analyzed at preschool age. At six years of age, a classification (healthy, transient wheeze, or asthma) was based on symptoms, lung function, and medication use.

RESULTS

The ICAM1 rs5498 A allele was positively associated with asthma development (p = 0.02) and ICAM1 gene expression (p = 0.01). ICAM1 gene expression was positively associated with exhaled levels of soluble ICAM1 (p = 0.04) which in turn was positively associated with asthma development (p = 0.01). Furthermore, rs1800872 and rs1800896 in IL10 were associated with altered IL10 mRNA expression (p < 0.01). Exhaled levels of IL4, IL10, and IL13 were positively associated with asthma development (p < 0.01).

CONCLUSIONS

In this unique prospective study, we demonstrated that ICAM1 is associated with asthma development on DNA, mRNA, and protein level. Thus, ICAM1 is likely to be involved in the development of childhood asthma.

Rhinovirus infections and adenoidal hypertrophy: do they interact with atopy in children?

Modern diagnostic methods allow the evaluation of the connection between rhinoviruses and atopy. Recent studies suggest that rhinoviruses are present in the adenoids at higher titers than in other specific sites, after inoculation of nasal mucosa or conjunctiva in volunteers. Therefore, it is possible that they might be responsible for specific local changes, while such changes may be influenced by atopy. This review focuses on the interactions between rhinoviral infection, the host's immune status and adenoidal disease.

Cell surface antigen expression by peripheral blood monocytes in allergic asthma: results of 2.5 years therapy with inhaled beclomethasone dipropionate

At present, inhaled glucocorticoids are widely accepted as the therapy of choice in chronic asthma. Treatment with inhaled glucocorticoids significantly suppresses local airway inflammation in asthmatics, but may also have systemic effects, e.g. a reduction of the number of circulating hypodense eosinophils or a down-modulation of HLA-DR antigen (Ag) expression by T lymphocytes in peripheral blood. However, the effect of long-term therapy with inhaled glucocorticoids on peripheral blood monocytes (PBM), which are the precursors of the most numerous cell type in the lung, the alveolar macrophage, have not yet been evaluated. We therefore investigated the expression of various cell surface Ag on PBM from non-smoking patients with allergic asthma who were treated for 2.5 years with a β₂-receptor agonist plus either an inhaled glucocorticoid (beclomethasone dipropionate, BDP) (n = 4) or an anticholinergic or placebo (n = 8). We compared the results with healthy volunteers (n = 7). Long-term treatment of allergic asthmatics with inhaled BDP, but not anticholinergic or placebo therapy, was associated with a significantly lower CDllb Ag expression (p < 0.04) and higher expression of CD13, CD14 and CD18 Ag (p < 0.05, p < 0.02 and p < 0.04, respectively) when compared with the healthy control subjects (n = 7). Most interestingly, PBM of asthmatics treated with inhaled BDP expressed an almost two-fold higher level of CD14 Ag on their cell surface than PBM of patients treated with anticholinergic or placebo (p < 0.03). No significant differences in the expression of CD16, CD23, CD25, CD32 and CD64 Ag or HLA-DR were observed between PBM from the different patient groups or healthy controls. Taken together, this study shows that long-term local therapy with inhaled BDP coincides with an altered expression of at least one cell surface Ag on PBM from allergic asthmatics.

RG-II from Panax ginseng C.A. Meyer suppresses asthmatic reaction

In asthma, T helper 2 (T(H)2)-type cytokines such as interleukin (IL)-4, IL-5, and IL-13 are produced by activated CD4(+) T cells. Dendritic cells played an important role in determining the fate of naive T cells into either T(H)1 or T(H)2 cells. We determined whether RG-II regulates the T(H)1/T(H)2 immune response by using an ovalbumin-induced murine model of asthma. RG-II reduced IL-4 production but increased interferon- gamma production, and inhibited GATA-3 gene expression. RG-II also inhibited asthmatic reactions including an increase in the number of eosinophils in bronchoalveolar lavage fluid, an increase in inflammatory cell infiltration in lung tissues, airway luminal narrowing, and airway hyperresponsiveness. This study provides evidence that RG-II plays a critical role in ameliorating the pathogenic process of asthmatic inflammation in mice. These findings provide new insights into the immunotherapeutic role of RG-II in terms of its effects in a murine model of asthma.

Mast cells play a key role in Th2 cytokine-dependent asthma model through production of adhesion molecules by liberation of TNF-α

Mast cells are well recognized as key cells in allergic reactions, such as asthma and allergic airway diseases. However, the effects of mast cells and TNF-α on T-helper type 2 (Th2) cytokine-dependent asthma are not clearly understood. Therefore, an aim of this study was to investigate the role of mast cells on Th2 cytokine-dependent airway hyperresponsiveness and inflammation. We used genetically mast cell-deficient WBB6F1/J-Kitw/Kitw-v (W/Wv), congenic normal WBB6F1/J-Kit+/Kit+ (+/+), and mast cell-reconstituted W/Wv mouse models of allergic asthma to investigate the role of mast cells in Th2 cytokine-dependent asthma induced by ovalbumin (OVA). And we investigated whether the intratracheal injection of TNF-α directly induce the expression of ICAM-1 and VCAM-1 in W/Wv mice. This study, with OVA-sensitized and OVA-challenged mice, revealed the following typical histopathologic features of allergic diseases: increased inflammatory cells of the airway, airway hyperresponsiveness, and increased levels of TNF-α, intercellular adhesion molecule (ICAM)-1, and vascular cellular adhesion molecule (VCAM)-1. However, the histopathologic features and levels of ICAM-1 and VCAM-1 proteins in W/Wv mice after OVA challenges were significantly inhibited. Moreover, mast cell-reconstituted W/Wv mice showed restoration of histopathologic features and recovery of ICAM-1 and VCAM-1 protein levels that were similar to those found in +/+ mice. Intratracheal administration of TNF-α resulted in increased ICAM-1 and VCAM-1 protein levels in W/Wv mice. These results suggest that mast cells play a key role in a Th2 cytokine-dependent asthma model through production of adhesion molecules, including ICAM-1 and VCAM-1, by liberation of TNF-α.

Modulation by flunisolide of tumor necrosis factor-alpha-induced stimulation of airway epithelial cell activities related to eosinophil inflammation

BACKGROUND

Tumor necrosis factor (TNF)-alpha, a proinflammatory cytokine involved in the pathogenesis of asthma, displays multiple functions on a variety of cells, including bronchial epithelial cells (BECs).

OBJECTIVE

To characterize in vitro changes induced by TNF-alpha on the function of BECs that may be related to eosinophilic inflammation and to evaluate their modulation by an inhaled corticosteroid, flunisolide.

METHODS

A normal human bronchial epithelial cell line (BEAS-2B) was incubated with TNF-alpha (10 ng/ml) to evaluate (a) intercellular adhesion molecule (ICAM)-1 expression and granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-5 release by BEAS-2B; (b) eosinophil adhesion to BEAS-2B; and (c) the modulation of these activities by flunisolide (0.1 to 10 microM).

RESULTS

Stimulation of BEAS-2 with TNF-alpha generated an increase in ICAM-1 expression (p = .0012), in GM-CSF and IL-5 release (p < .01), and in eosinophil adhesion to BEAS-2B, but this latter effect did not reach statistical significance. Flunisolide at all the tested concentrations effectively inhibited ICAM-1 expression and GM-CSF and IL-5 release (p < .05). The percent inhibition induced by the highest flunisolide concentration (10 muM) for the various BEAS-2B functions was 30%, 60%, and 70%, respectively. The effect of flunisolide appeared to be related to an inhibition of "TNF-alpha-induced" ICAM-1 expression and cytokine release with little or no involvement of the "constitutive" expression and release.

CONCLUSION

An increase in ICAM-1 expression in BECs was found to be induced by TNF-alpha and associated with enhancement of the constitutive secretion of GM-CSF and IL-5, cytokines related to eosinophilic inflammation. The ability of flunisolide to modulate these BECs activities appears to be mostly related to the inhibition of the "TNF-alpha-induced" responses.

PTEN as a unique promising therapeutic target for occupational asthma

The tumor suppressor phosphatase and tensin homologue deleted on chromosome ten (PTEN) dephophorylates phosphatidylinositol 3,4,5-triphosphate (PIP3) and is a key negative regulator of phosphoinositide kinase-3 (PI3K) signaling pathway. PTEN also suppresses cellular motility through mechanisms that may be partially independent of phosphatase activity. PTEN is one of the most commonly lost tumor suppressors in human cancers, and its down-regulation is also implicated in several other diseases including airway inflammatory diseases. There is increasing evidence regarding the protective effects of PTEN on the bronchial asthma which is induced by complex signaling networks. Very recently, as for the occupational asthma (OA) with considerable controversy for its pathobiologic mechanisms, PTEN has been considered as a key molecule which is capable of protecting toluene diisocyanate (TDI)-induced asthma, suggesting that PTEN is located at switching point of various molecular signals in OA. Knowledge of the mechanisms of PTEN regulation/function could direct to the pharmacological manipulation of PTEN. This article reviews the latest knowledge and studies on the roles and mechanisms of PTEN in OA.

Apigenin protects ovalbumin-induced asthma through the regulation of GATA-3 gene

Apigenin, a dietary plant-flavonoid has shown anti-inflammatory and anticancer properties, however the molecular basis of this effect remains to be elucidated. Thus we elucidated to anti-allergic effect of apigenin in ovalbumin (OVA)-induced asthma model mice. The OVA-induced mice showed allergic airway reactions. It included an increase in the number of eosinophils in bronchoalveolar lavage (BAL) fluid, an increase in inflammatory cell infiltration into the lung around blood vessels and airways, airway luminal narrowing, and the development of airway hyper-responsiveness (AHR). The administration of apigenin before the last airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. Accordingly, this study may provide evidence that apigenin plays a critical role in the amelioration of the pathogenetic process of asthma in mice. These findings provide new insight into the immunopharmacological role of apigenin in terms of its effects in a murine model of asthma.

Angiopoietin-1 variant, COMP-Ang1 attenuates hydrogen peroxide-induced acute lung injury

Reactive oxygen species (ROS) play a crucial role in acute lung injury. Tissue inflammation, the increased vascular permeability, and plasma exudation are cardinal features of acute lung injury. Angiopoietin-1 (Ang1) has potential therapeutic applications in preventing vascular leakage and also has beneficial effects in several inflammatory disorders. Recently developed COMP-Ang1 is more potent than native Ang1 in phosphorylating tyrosine kinase with immunoglobulin and EGF homology domain 2 receptor in endothelial cells. However, there are no data on effects and related molecular mechanisms of COMP- Ang1 on ROS-induced acute lung injury. We used hydrogen peroxide (H2O2)-inhaled mice to evaluate the effect of COMP-Ang1 on pulmonary inflammation, bronchial hyper-responsiveness, and vascular leakage in acute lung injury. The results have revealed that VEGF expression, the levels of IL-4, TNF-alpha, IL-1beta, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 in lungs, the levels of hypoxia-inducible factor-1alpha (HIF-1alpha) and NF-kappaB in nuclear protein extracts, phosphorylation of Akt, and vascular permeability were increased after inhalation of H2O2 and that the administration of COMP-Ang1 markedly reduced airway hyper-responsiveness, pulmonary inflammation, plasma extravasation, and the increases of cytokines, adhesion molecules, and VEGF in lungs treated with H2O2. We have also found that the activation of HIF-1a and NF-kB and the increase of phosphoinositide 3-kinase activity in lung tissues after H2O2 inhalation were decreased by the administration of COMP-Ang1. These results suggest that COMP-Ang1 ameliorates ROS-induced acute lung injury through attenuating vascular leakage and modulating inflammatory mediators.

Quercetin regulates Th1/Th2 balance in a murine model of asthma

Quercetin is found to be the most active of the flavonoids in studies and many medicinal plants owe much of their activity to their high Quercetin content. Quercetin has demonstrated significant anti-inflammatory activity because of direct inhibition of several initial processes of inflammation. However, its anti-allergic effect in the Th1/Th2 immune response was poorly understood. Recently, it was shown that T-bet and GATA-3 were master Th1 and Th2 regulatory transcription factors. In this study, we have attempted to determine whether Quercetin regulates Th1/Th2 cytokine production, T-bet and GATA-3 gene expression in OVA-induced asthma model mice. Quercetin reduced the increased levels of IL-4, Th2 cytokine production in OVA-sensitized and -challenged mice. The other side, it increased IFN-gamma, Th1 cytokine production in Quercetin administrated mice. We also examined to ascertain whether Quercetin could influence Eosinophil peroxidase (EPO) activity. The administration of Quercetin before the last airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. Accordingly, this study may provide evidence that Quercetin plays a critical role in the amelioration of the pathogenetic process of asthma in mice. These findings provide new insight into the immunopharmacological role of Quercetin in terms of its effects in a murine model of asthma, and also broaden current perspectives in our understanding of the immunopharmacological functions of Quercetin.

Lycopene suppresses ovalbumin-induced airway inflammation in a murine model of asthma

In this study, we attempt to determine whether lycopene regulates inflammatory mediators in the ovalbumin (OVA)-induced murine asthma model. To address this, mice were sensitized and challenged with OVA, and then treated with lycopene before the last OVA challenge. Administration of lycopene significantly alleviated the OVA-induced airway hyperresponsiveness to inhaled methacholine. Administration of lycopene also resulted in a significant inhibition of the infiltration of inflammatory immunocytes into the bronchoalveolar lavage, and attenuated the gelatinolytic activity of matrix metalloproteinase-9 and the expression of eosinophil peroxidase. Additionally, lycopene reduced the increased levels of GATA-3 mRNA level and IL-4 expression in OVA-challenged mice. However, it increased T-bet mRNA level and IFN-gamma expression in lycopene-challenged mice. These findings provide new insight into the immunopharmacological role of lycopene in terms of its effects in a murine model of asthma.

Circulating adhesion molecules in tuberculosis

Leucocyte-endothelial adhesion molecules have been implicated in the pathogenesis of inflammatory diseases. To evaluate their role as markers of disease activity in tuberculosis, we have used an antigen capture ELISA to measure the serum concentrations of circulating intercellular adhesion molecule-1 (cICAM-1), E-selectin (cE-selectin) and vascular cell adhesion molecule-1 (cVCAM-1) in 34 patients with active tuberculosis (27 with pulmonary disease and seven with lymph node disease) before the commencement of standard chemotherapy, 15 subjects who had previously completed treatment for pulmonary tuberculosis, and 27 healthy volunteers. Circulating ICAM-1 and E-selectin levels were significantly elevated in patients with active tuberculosis when compared to those with treated disease (P⩽0.01), and healthy controls (P&lt; 0.02). Circulating VCAM-1 was raised in patients with active or old pulmonary tuberculosis (P&lt;0.02 versus healthy controls) but not in those with tuberculous lymphadenitis. Significant correlations were observed between the levels of cICAM-1 and cE-selectin (ρ= 0-63, P=0 0001), and between cICAM-1 and cVCAM-1 (ρ = 0.28, P=0.016). Taking the mean +2 s.d. of the serum level in healthy controls as the upper limit of normal range, circulating ICAM-1 had the best discriminative power in identifying active tuberculosis, being elevated in about 80% of patients but was raised in only 6.7% of subjects with treated disease and in 3.7% of normal subjects. Our data support the possibility that three adhesion molecules may be involved in the pathogenesis of tuberculosis and cICAM-1 may be a useful marker of disease activity.

The histamine-induced enhanced expression of vascular cell adhesion molecule-1 by nasal polyp-derived fibroblasts is inhibited by levocetirizine

BACKGROUND

Histamine, a key chemical mediator in allergic reaction, exhibits an array of pro-inflammatory effects that include the activation of fibroblasts. The aim of this study was to evaluate whether histamine could stimulate nasal polyp-derived fibroblasts to express vascular cell adhesion molecule (VCAM)-1, a surface molecule involved in structural-inflammatory cell interaction and whether levocetirizine could inhibit this induction.

METHODS

Primary nasal polyp tissue-derived fibroblasts were stimulated with histamine (10-1000 microM) or interleukin (IL)-4 plus tumor necrosis factor (TNF)-alpha (0.5-5 ng/mL) and VCAM-1 expression was evaluated by flow cytometry analysis. The inhibitory effect of the selective H1-antagonist levocetirizine (0.01-10.0 microM) on VCAM-1 expression was also tested.

RESULTS

Compared with unstimulated cultures, histamine or IL-4 + TNF-alpha, at the highest concentrations tested, significantly increase VCAM-1 expression (p < 0.05). To evaluate the ability of levocetirizine to downregulate VCAM-1 expression, fibroblasts were stimulated with histamine (1000 microM) or IL-4 + TNF-alpha (5 ng/mL), in the presence of the drug (0.01-10.0 microM). The histamine-induced VCAM-1 expression was effectively inhibited by levocetirizine (0.1-10.0 microM) (p < 0.05). No effect of the drug on IL-4 + TNF-alpha-induced VCAM-1 expression was observed.

CONCLUSIONS

Histamine upregulates VCAM-1 expression on nasal polyp-derived fibroblasts and this phenomenon, relevant to allergic late-phase inflammation, is effectively inhibited by levocetirizine.

D-pinitol regulates Th1/Th2 balance via suppressing Th2 immune response in ovalbumin-induced asthma

D-pinitol has been demonstrated to exert insulin-like and anti-inflammatory activities. However, its anti-allergic effect in the Th1/Th2 immune response is poorly understood. Recently, it was shown that T-bet and GATA-3 are master Th1 and Th2 regulatory transcription factors. In this study, we have attempted to determine whether D-pinitol regulates Th1/Th2 cytokine production, T-bet and GATA-3 gene expression in OVA-induced asthma model mice. We also examined to ascertain whether D-pinitol could influence eosinophil peroxidase (EPO) activity. After being sensitized and challenged with ovalbumin (OVA) showed typical asthmatic reactions. These reactions included an increase in the number of eosinophils in bronchoalveolar lavage (BAL) fluid, an increase in inflammatory cell infiltration into the lung tissue around blood vessels and airways, airway luminal narrowing, and the development of airway hyper-responsiveness (AHR). The administration of D-pinitol before the last airway OVA challenge resulted in a significant inhibition of all asthmatic reactions. Accordingly, this study may provide evidence that D-pinitol plays a critical role in the amelioration of the pathogenetic process of asthma in mice. These findings provide new insight into the immunopharmacological role of D-pinitol in terms of its effects in a murine model of asthma, and also broaden current perspectives in our understanding of the immunopharmacological functions of D-pinitol.

Comparative study of topical anti-allergic eye drops on human conjunctiva-derived cells: responses to histamine and IFNγ and toxicological profiles

BACKGROUND

The purpose of the study was to compare toxic effects and responses to histamine and IFN gamma associated with the use of some widely used anti-allergic eye drops commercially available today.

METHODS

For dynamic studies, the Wong-Kilbourne cell line was stimulated for 24 h with histamine or IFN gamma in the presence or absence of anti-allergic eye drops. Supernatants of histamine-stimulated cells were evaluated for the production of IL-6 and IL-8 by ELISA, while the expression of ICAM-1 was evaluated by flow cytometry on IFN gamma-stimulated cells. Toxicological assays were performed using cold light cytofluorometry: viability and apoptosis as well as reactive oxygen species (ROS) and O2(.)- production were assessed using neutral red, Hoechst/propidium iodide, H(2)-DCFDA and hydroethidine tests, respectively.

RESULTS

Antihistamines reduced IL-6 release and presented dose-dependent inhibitory effects on IL-8 production. None of the eye drops decreased the basal or IFN gamma-stimulated expression of ICAM-1. Conversely, eye drops preserved with benzalkonium chloride (BAC) induced even higher ICAM-1 expression levels on IFN gamma-stimulated cells than did IFN gamma alone, whereas unpreserved drugs had no effect. Toxicological assays confirmed the pivotal role of BAC in proportionally reducing cell viability while increasing apoptosis and oxidative stress.

CONCLUSIONS

The ability of topical ocular anti-H(1) drugs to significantly reduce the production of IL-6 and IL-8 argues that they may help treat the inflammatory processes occurring in allergic ocular surface disorders. Nevertheless, preserved ophthalmic formulations may enhance epithelial conjunctival expression of ICAM-1 in the presence of a low inflammatory stimulus, such as IFN gamma, and displayed toxic as well as pro-oxidative effects on these cells. Therefore, BAC used as preservative might in part interfere with the potential anti-inflammatory properties of the active compound by modulating the immuno-inflammatory response of epithelial conjunctival cells.

Inhibition of phosphoinositide 3-kinase delta attenuates allergic airway inflammation and hyperresponsiveness in murine asthma model

P110delta phosphoinositide 3-kinase (PI3K) plays a pivotal role in the recruitment and activation of certain inflammatory cells. Recent findings revealed that the activity of p110delta also contributes to allergen-IgE-induced mast cell activation and vascular permeability. We investigated the role of p110delta in allergic airway inflammation and hyperresponsiveness using IC87114, a selective p110delta inhibitor, in a mouse asthma model. BALB/c mice were sensitized with OVA and, upon OVA aerosol challenge, developed airway eosinophilia, mucus hypersecretion, elevation in cytokine and chemokine levels, up-regulation of ICAM-1 and VCAM-1 expression, and airway hyperresponsiveness. Intratracheal administration of IC87114 significantly (P<0.05) attenuated OVA-induced influx into lungs of total leukocytes, eosinophils, neutrophils, and lymphocytes, as well as levels of IL-4, IL-5, IL-13, and RANTES in a dose-dependent manner. IC87114 also significantly (P<0.05) reduced the serum levels of total IgE and OVA-specific IgE and LTC(4) release into the airspace. Histological studies show that IC87114 inhibited OVA-induced lung tissue eosinophilia, airway mucus production, and inflammation score. In addition, IC87114 significantly (P<0.05) suppressed OVA-induced airway hyperresponsiveness to inhaled methacholine. Western blot analyses of whole lung tissue lysates shows that IC87114 markedly attenuated the OVA-induced increase in expression of IL-4, IL-5, IL-13, ICAM-1, VCAM-1, RANTES, and eotaxin. Furthermore, IC87114 treatment markedly attenuated OVA-induced serine phosphorylation of Akt, a downstream effector of PI3K signaling. Taken together, our findings implicate that inhibition of p110delta signaling pathway may have therapeutic potential for the treatment of allergic airway inflammation.

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) reduces vascular endothelial growth factor expression in allergen-induced airway inflammation

Vascular endothelial growth factor (VEGF) plays a pivotal role in the pathogenesis of bronchial asthma. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) has been implicated in regulating cell survival signaling through the phosphoinositide 3-kinase (PI3K)/Akt pathway. The key role of PI3K in VEGF-mediated signal transduction is established. However, the effects of PTEN on VEGF-mediated signaling in asthma are unknown. This study aimed to determine the effect of PI3K inhibitors and PTEN on VEGF expression in allergen-induced airway inflammation. We have used a female C57BL/6 mouse model for asthma to determine the role of PTEN in allergen-induced airway inflammation, specifically in the expression of VEGF. Allergen-induced airway inflammation leads to increased activity of PI3K in lung tissue. These mice develop the following typical pathophysiological features of asthma in the lungs: increased numbers of inflammatory cells of the airways; airway hyper-responsiveness; increased expression of interleukin (IL)-4, IL-5, IL-13, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, regulated on activation normal T cell expressed and secreted (RANTES), and eotaxin; increased vascular permeability; and increased levels of VEGF. Administration of PI3K inhibitors or adenoviruses carrying PTEN cDNA reduced the symptoms of asthma and decreased the increased levels of plasma extravasation and VEGF in allergen-induced asthmatic lungs. These results indicate that PTEN reduces VEGF expression in allergen-induced airway inflammation.

Epigallocatechin-3-gallate protects toluene diisocyanate-induced airway inflammation in a murine model of asthma

Epigallocatechin-3-gallate (EGCG), a major form of tea catechin, has anti-allergic properties. To elucidate the anti-allergic mechanisms of EGCG, we investigated its regulation of matrix metalloproteinase (MMP-9) expression in toluene diisocyanate (TDI)-inhalation lung tissues as well as TNF-alpha and Th2 cytokine (IL-5) production in BAL fluid. Compared with untreated asthmatic mice those administrated with EGCG had significantly reduced asthmatic reaction. Also, increased reactive oxygen species (ROS) generation by TDI inhalation was diminished by administration of EGCG in BAL fluid. These results suggest that EGCG regulates inflammatory cell migration possibly by suppressing MMP-9 production and ROS generation, and indicate that EGCG may be useful as an adjuvant therapy for bronchial asthma.

Modulation of the constitutive or cytokine-induced bronchial epithelial cell functions in vitro by fluticasone propionate

When exposed to proinflammatory mediators, human bronchial epithelial cells (HBECs) upregulate the 'constitutive' adhesion molecule expression and cytokine/chemokine release. We tested whether and to what extent the inhibitory effect of fluticasone propionate on HBECs could involve the 'constitutive' and 'cytokine-induced' proinflammatory functions. Stimulation of the HBECs with interleukin (IL)-4 plus tumour necrosis factor (TNF)-alpha was more effective in upregulating intercellular adhesion molecule (ICAM)-1 ( approximately 2.2-fold increase) than vascular adhesion molecule (VCAM)-1 ( approximately 1.6-fold increase) expression (P<0.05) and in increasing the release of 'regulated on activation normal T cell expressed' (RANTES, 5.7-fold increase) than of IL-8 (3.5-fold increase) and granulocyte macrophage-colony stimulating factor (GM-CSF, 2.8-fold increase), (P<0.01). Fluticasone propionate, at the two concentrations tested (10 and 100 nM), was more effective in inhibiting the 'IL-4 plus TNF-alpha-induced' ICAM-1 expression than VCAM-1 expression (P<0.05) and in downregulating RANTES than IL-8 or GM-CSF secretion (P<0.05). The degree of inhibition demonstrated by fluticasone propionate appeared to be related to the degree of cell activation. In addition, for both adhesion molecules, the effect of fluticasone propionate at both concentrations tested appeared to be related to a complete inhibition of 'IL-4 plus TNF-alpha-induced' expression with no involvement of the 'constitutive' expression. Slightly different results were observed for cytokine/chemokine release. Indeed, evaluating RANTES, a complete inhibition of the 'IL-4 plus TNF-alpha-induced' release with a partial inhibition also of the 'constitutive' release at both concentrations of the drug tested was found, whereas for GM-CSF and IL-8, only a partial inhibition of the 'IL-4 plus TNF-alpha-induced' release in the presence of fluticasone propionate 10 and 100 nM. Thus, HBECs can constitutively or upon activation express adhesion molecules and secrete proinflammatory proteins at various levels and the different ability of fluticasone propionate to modulate the HBEC functions appears to be mostly related to the different inhibition of the various 'IL-4 plus TNF-alpha-induced' responses.

Epithelial cells and fibroblasts: structural repair and remodelling in the airways

Extensive lesions and changes in the architecture of the airway walls are commonly described in patients with respiratory infections, asthma, chronic bronchitis and interstitial lung diseases. Current knowledge identifies in airway epithelial cells and in fibroblasts the two cell types mainly involved in tissue repair after injury. During inflammatory respiratory disorders, extensive injury of airway epithelium may occur, with shedding of a large sheet of damaged cells in the bronchial and alveolar lumen but also with activation of the surviving epithelial cells and of the underlying fibroblasts. Indeed, besides acting as a physical and functional barrier to external agents, the epithelial surface of the bronchi has the capability to modulate the repair processes through the secretion of extracellular matrix proteins and the interaction with interstitial fibroblasts. Besides releasing pro-inflammatory cytokines and chemokines, the surviving epithelial cells and the underlying fibroblasts secrete factors contributing to airway repair, including the formation of the provisional extracellular matrix. This is indeed the substrate to which the epithelial cells at the edge of the lesion can attach to migrate in order to reconstitute the surface layer. In these processes airway epithelial cells receive the support of bronchial wall fibroblasts which actively release cytokines stimulating epithelial cell functions.

Concentration-dependent effects of mometasone furoate and dexamethasone on foetal lung fibroblast functions involved in airway inflammation and remodeling

Lung fibroblasts play a key role in the pathogenesis of airway inflammation and remodeling through the release of mediators and the expression of surface molecules connected with cell-cell and cell-extracellular matrix interaction. The aim of the study was to evaluate the inhibitory effect of two corticosteroids, mometasone furoate (MOM) and dexamethasone (DEX), respectively, on a variety of fibroblast functions: DNA synthesis and proliferation, expression of adhesion molecules [intercellular adhesion molecule-1 (ICAM-1, CD54) and hyaluronic cellular adhesion molecule (HCAM, CD44)] and release of chemokines/cytokines [monocyte chemoattractant protein (MCP)-1, eotaxin, interleukin (IL)-6 and transforming growth factor (TGF)-beta]. Cells from a human foetal lung fibroblast cell line (GM 06114) were stimulated with basic fibroblast growth factor (bFGF) or tumour necrosis factor (TNF)-alpha in the presence of different concentrations (0.01-100.0nM) of MOM or DEX. A significant increase in fibroblast DNA synthesis and proliferation was observed when the cells were stimulated with bFGF (p<0.05), whereas TNF-alpha induced a significant upregulation in ICAM-1 expression and in MCP-1, eotaxin and IL-6 release (p<0.05, each comparison). No changes in HCAM expression and in TGF-beta release were observed (p>0.05, each comparison). The addition of MOM or DEX at the beginning of the cell cultures induced a significant downregulation in fibroblast DNA synthesis and proliferation, ICAM-1 and HCAM expression and chemokine/cytokine release (p<0.05, each comparison). At all the concentrations tested, MOM was more effective than DEX in inhibiting ICAM-1 expression and MCP-1 release (p<0.05, each comparison), whereas no potency advantage for MOM was detected in DNA synthesis, cell proliferation, HCAM expression and in eotaxin, IL-6 and TGF-beta release (p>0.05, each comparisons). These results extend the profile of the anti-inflammatory activity of mometasone furoate to lung fibroblast functions involved in airway inflammation and remodeling.

Cytokine release and adhesion molecule expression by stimulated human bronchial epithelial cells are downregulated by salmeterol

Summary beta2-adrenoreceptor agonists are able to modulate various aspects of airway cell functions involved in the inflammatory and repair processes characterizing a variety of respiratory disorders. Human bronchial epithelial cells (HBECs), which can act as immune effector cells and express beta2-adrenoreceptors, were used to test the effects of different concentrations (0.1-100.0 nM) of salmeterol (Salm) on adhesion molecule expression and chemokine/cytokine release. HBECs, freshly isolated from resected bronchi at the time of surgery in ex-smokers with lung cancer, constitutively expressed over 3 times more ICAM-1 than VCAM-1 (P<0.05) and secreted greater amounts of IL-8 than of GM-CSF or RANTES (P<0.001). Stimulation of HBECs with IL-4, TNF-alpha or IL-4 plus TNF-alpha-upregulated ICAM-1 expression (P<0.05) and increased GM-CSF and IL-8 secretion (P<0.05). Similarly, VCAM-1 expression was significantly increased by IL-4 plus TNF-alpha, while RANTES release was significantly enhanced by IL-4 or by IL-4 plus TNF-alpha (P<0.05), but not by TNF-alpha alone (P>0.05). Dose-response curves showed that Salm, at concentration >1.0 nM, was effective in inhibiting adhesion molecule expression and cytokine release by HBECs (P<0.05). At a Salm concentration of 10 nM the degree of inhibition observed was similar for ICAM-1 and VCAM-1 expression (37.2 +/- 9.3% and 32.9 +/- 9.6%, respectively; P>0.05), but higher for RANTES (88.4 +/- 4.4%), as compared to IL-8 (21.8 +/- 7.0%) or GM-CSF (30.1 +/- 6.6%; P<0.05, each comparison). Thus, adhesion molecules and cytokines may be expressed/released at very different levels by unstimulated or stimulated HBECs and those activities appear to be modulated by Salm.

Elevated levels of circulating adhesion molecules in patients with active pulmonary tuberculosis

OBJECTIVE

Recent studies have indicated the importance of cell adhesion molecules in the pathogenesis of various inflammatory lung diseases. Our study was designed to determine whether five soluble adhesion molecules including soluble L-, E- and P-selectin (sL-, sE- and sP-selectin), intercellular adhesion molecule-1 (sICAM-1), and vascular cell adhesion molecule-1 (sVCAM-1) in serum reflect the severity of active pulmonary tuberculosis (TB), and whether there is a distinct profile of these soluble molecules in this disease.

METHODOLOGY

Using enzyme-linked immunosorbent assays, we measured the serum levels of these five soluble adhesion molecules in 31 patients with active TB and 11 healthy volunteers.

RESULTS

Serum levels of sE-selectin, sP-selectin and sICAM-1, but not sL-selectin or sVCAM-1, were significantly higher in patients with active TB than in the control subjects (P < 0.001, each). Significant correlations were detected only between serum levels of sE-selectin and sP-selectin, sE-selectin and sICAM-1, and sP-selectin and sICAM-1. There was a significant correlation between the Gaffky scale result (a scale assessing the number of mycobacteria bacilli present) and all of the above adhesion molecules, except for sL-selectin. Serum levels of sE-selectin, sL-selectin and sICAM-1 also correlated with the CXR radiological score. Higher levels of sL-selectin and sICAM-1 were detected in the serum of patients with radiological cavity formation compared to those without. The ESR, C-reactive protein and circulating neutrophil counts all correlated significantly with sE-selectin, sP-selectin, sICAM-1 and sVCAM-1.

CONCLUSION

The results suggest that there is a distinct profile of soluble adhesion molecules in active pulmonary TB and that sE-selectin, sP-selectin, and especially sICAM-1 appear to be the most sensitive clinical measures of disease severity.

Matrix metalloproteinase inhibitor regulates inflammatory cell migration by reducing ICAM-1 and VCAM-1 expression in a murine model of toluene diisocyanate-induced asthma

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) has been reported to play a crucial role in the transmigration of neutrophils, lymphocytes, and eosinophils. Neutrophils, eosinophils, and lymphocytes migrate from the blood to the lungs in response to inflammatory mediators produced in the airways and are subsequently released into the circulation. This traffic is mediated by adhesion molecules. However, little is known about the migration of inflammatory cells through the endothelial and epithelial basement membranes in toluene diisocyanate (TDI)-induced asthma.

OBJECTIVES

An aim of this study was to evaluate the effect of MMP inhibitors on the expression of ICAM-1 and VCAM-1 in the migration of inflammatory cells in a murine model of TDI-induced asthma.

METHODS

We used a murine model to investigate TDI-induced asthma to examine the possible involvement of ICAM-1 and VCAM-1 in the pathogenesis of that disease and the effect of MMP inhibitors on the expression of ICAM-1 and VCAM-1.

RESULTS

In mice, the following typical pathophysiologic features develop in the lungs: increased numbers of inflammatory cells and increased expression of MMP-9, ICAM-1, and VCAM-1 mRNA and protein. Administration of MMP inhibitors reduced the increased numbers of inflammatory cells and the increased expression of ICAM-1 and VCAM-1 mRNA expression and protein. In addition, MMP inhibitors significantly abrogated the increased expression of IL-1beta, IL-4, and TNF-alpha mRNA in lung tissues and levels of IL-1beta, IL-4, and TNF-alpha in bronchoalveolar lavage fluids after TDI inhalation.

CONCLUSIONS

These results suggest that MMP inhibitors regulate inflammatory cell migration by reducing ICAM-1 and VCAM-1 expression and possibly also by suppressing IL-1beta, IL-4, and TNF-alpha expression.

The antiinflammatory activity of budesonide on human airway epithelial cells is lasting after removal of the drug from cultures

Because of its ability to conjugate extensively with fatty acids within lung cells, it has been suggested that budesonide (Bud) may have a prolonged pharmacologic activity, related to retention of the drug in airway tissues. Using human bronchial epithelial cells (HBECs) as target cells, we evaluated whether Bud could have a long-lasting inhibitory effect on ICAM-1 expression and GM-CSF release. HBECs were cultured in Bud (10 microM) or in medium alone (Ctr) for 24 hr, then extensively washed (to remove Bud) and incubated for an additional 6, 12, or 24 hr with IFN-gamma. ICAM-1 expression and GM-CSF release were then measured by flow cytometric analysis. In Ctr HBECs, IFN-gamma induced a time-dependent upregulation of ICAM-1 expression, significant at 6, 12, or 24 hr (p < 0.05, each comparison), and an increase in GM-CSF release, significant at 24 hr (p < 0.05). The inhibitory effects of Bud preexposure on IFN-gamma-induced ICAM-1 expression and GM-CSF release were then compared with those of a continuous exposure to the drug during IFN-gamma stimulation. Preexposure to Bud (1 and 10 microM) induced a significant inhibition of IFN-gamma-induced ICAM-1 expression (p < 0.05, each comparison), but lower than that observed in HBECs continuously exposed at the same Bud concentrations (p < 0.01, each comparison). In contrast, the inhibition of GM-CSF release was similar in preexposed and in exposed HBECs and statistically significant only at the highest Bud concentration tested (p < 0.05, each comparison). Thus, Bud is effective in vitro in inducing a downregulation lasting 24 hr of mechanisms involved in leukocyte recruitment.

Expression of integrins in human cultured mesothelial cells: the roles in cell-to-extracellular matrix adhesion and inhibition by RGD-containing peptide

Integrins play key roles in cell-to-cell and cell-to-extracellular matrix (ECM) adhesion. We investigated integrin expression on pleural mesothelial cells (PMCs) and the inhibitory effect of arginine-glycine-asparate (RGD)-containing peptide on the adhesion of PMCs to fibronectin and collagen. Using flow cytometry and immunostaining, PMCs freshly isolated from pleural effusions and one mesothelial cell line were screened for different integrins. Intact pleural tissue was evaluated by immunohistochemistry. The adhesion of Met-5A cells to fibronectin and collagen types I, III and IV was assayed with prior treatment of various concentrations of glycine-arginine-glycine aspartate-serine (GRGDS). On primary PMCs, alpha2, alpha3, alpha5, beta1, beta3 and alphavbeta3 were highly expressed (>70%); alpha1 expression was intermediate (30-70%); and alpha4 and alpha6 expressions were low (< 30%). On Met-SA cells, alpha3, alpha5, alpha6 and beta1 were highly expressed (>70%); alpha1 was intermediate (30-70%); and alpha2, alpha4, beta3 and alphavbeta3 were low (<30%). The patterns of immunostaining on pleural tissues were similar to the results of flow cytometry for primary PMCs except for beta3. There was no statistically different expression in various disease states (transudate vs. exudate, benign vs. malignant). The inhibitory effect of GRGDS peptide on Met-5A cell adhesion to all four matrix proteins was dose-dependent.

Inflammatory responses in the cerebral cortex after ischemia in the P7 neonatal Rat

BACKGROUND AND PURPOSE

The contribution of inflammatory response to the pathogenesis of ischemic lesions in the neonate is still uncertain. This study described the chronological sequence of inflammatory changes that follow cerebral ischemia with reperfusion in the neonatal P7 rat.

METHODS

P7 rats underwent left middle cerebral artery electrocoagulation associated with 1-hour left common carotid artery occlusion. The spatiotemporal pattern of cellular responses was characterized immunocytochemically with the use of antibodies against rat endogenous immunoglobulins to visualize the area of the breakdown of the blood-brain barrier. Infiltration of neutrophils and T lymphocytes was demonstrated by antibodies against myeloperoxidase and a pan-T cell marker, respectively. Antibodies ED1 and OX-42 were applied to identify microglial cells and macrophages. The response of astrocytes was shown with antibodies against glial fibrillary acidic protein. Cell survival was assessed by Bcl-2 expression. Cell death was demonstrated by DNA fragmentation with the use of the terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end labeling (TUNEL) assay and Bax immunodetection.

RESULTS

Endogenous immunoglobulin extravasation through the blood-brain barrier occurred at 2 hours of recirculation and persisted until 1 month after ischemia. Neutrophil infiltration began at 24 hours and peaked at 72 to 96 hours (30+/-3.4 neutrophils per 0.3 mm(2); P<0.0001), then disappeared at 14 days after ischemia. T cells were observed between 24 and 96 hours of reperfusion. Resident microglia-macrophages exhibited morphological remnants and expressed the cell death inhibitor Bcl-2 at 24 hours of recirculation. They became numerous within the next 48 hours and peaked at 7 days after ischemia. Phenotypic changes of resident astrocytes were apparent at 24 hours, and they proliferated between 48 hours and 7 days after ischemia. Progressively inflammatory cells showed DNA fragmentation and the cell death activator Bax expression. Cell elimination continued until there was a complete disappearance of the frontoparietal cortex.

CONCLUSIONS

These data demonstrate that perinatal ischemia with reperfusion triggers acute inflammatory responses with granulocytic cell infiltration, which may be involved in accelerating the destructive processes.

Modulation of HLA-DR antigen and ICAM-1 molecule expression on airway epithelial cells by sodium nedocromil

OBJECTIVE

To test in vitro and in vivo the hypothesis that sodium nedocromil could modulate the expression of surface molecules on airway epithelial cells.

METHODS

Human bronchial epithelial cells, obtained from surgically resected bronchi, were cultured and stimulated with recombinant IFN-gamma in the presence of sodium nedocromil. The intensity of the expression of surface molecules HLA-DR and ICAM-1 molecules on bronchial epithelial cells in vitro, was quantified by specific antibody staining and flow-cytometry analysis. Furthermore, we studied the effect of the drug on airway inflammation in vivo and on allergic rhinitis patients sensitized to house dust mites. Nasal epithelial cells were collected by brushing, at baseline and 2 to 3 weeks after treatment with sodium nedocromil. The expression of HLA-DR and ICAM-1 molecules was measured by flow-cytometry, and the proportions of neutrophils and eosinophils "contaminating" the epithelial cells evaluated by light microscopy examination of nasal brushings.

RESULTS

The enhanced HLA-DR and ICAM-1 expression, induced by IFN-gamma, was effectively downregulated, in a dose-dependent manner, by sodium nedocromil. At all the concentrations tested (10(-9) to 10(-4) M), the inhibitory activity of the drug was stronger on HLA-DR than on ICAM-1 expression (P<.05, all comparisons). As compared with healthy subjects, patients with allergic rhinitis had a higher expression of HLA-DR (P<.05) but not of ICAM-1 molecules (P>.05) on nasal epithelial cells, and higher proportions of nasal eosinophils (P<.05). Treatment with sodium nedocromil downregulated the expression of HLA-DR (P<.05), but not of ICAM-1 (P>.05), and induced a mild, but not statistically significant, decrease of nasal eosinophilia (P>.05).

CONCLUSION

These data demonstrate that the antiinflammatory activity of sodium nedocromil may include modulation of surface molecule expression on airway epithelial cells.

Expression of intercellular adhesion molecule-1 in rat inner ear due to bacterial otitis media

Expressions of anti-Streptococcus pneumoniae antibody and anti-intercellular adhesion molecule-1 (ICAM-1) antibody in the inner ear were studied immunohistochemically in rats following inoculation of S pneumoniae type 6A into the middle ear cavity. Positive staining with anti-S pneumoniae antibody was detected in the marginal cells of the stria vascularis of rats sacrificed 3 days after S pneumoniae inoculation, but almost no staining was detected in those sacrificed at 14 days. Strong ICAM-1 expression was detected in the basal cell layer of the stria vascularis of rats sacrificed 3 days after inoculation, but the intensity of the staining had decreased by 14 days. These results suggest that the stria vascularis may be a site of the inner ear damage that follows bacterial inoculation into the middle ear cavity. The up-regulated expression of ICAM-1 in the basal cell layer may represent a reaction of the inner ear to the bacterial otitis media.

Up-regulation of intercellular adhesion molecule-1 (ICAM-1), endothelial leucocyte adhesion molecule-1 (ELAM-1) and class II MHC molecules on pulmonary artery endothelial cells by antibodies against U1-ribonucleoprotein

In order to elucidate the pathogenic role(s) of autoantibodies in connective tissue disease (CTD), we examined whether autoantibodies against U1-ribonucleoprotein (RNP) and double-stranded (ds) DNA can up-regulate ICAM-1, ELAM-1 and class I and II MHC molecule expression on pulmonary artery endothelial cells (HPAEC). ICAM-1, ELAM-1 and class II MHC molecule expression on HPAEC cultured in the presence of anti-U1-RNP-containing and anti-dsDNA-containing IgG from CTD patients was up-regulated significantly in comparison with that on HPAEC cultured with IgG from normal healthy volunteers. Affinity chromatographic enrichment and depletion of the anti-U1-RNP antibody content of anti-U1-RNP-containing IgG confirmed that the anti-U1-RNP antibody did up-regulate ICAM-1, ELAM-1 and class II MHC molecule expression. The finding that an IgG F(ab')2-purified anti-U1-RNP antibody also up-regulated expression of these molecules may indicate that mechanisms other than Fc receptor-mediated stimulation are involved. These in vitro findings suggest that autoantibodies against U1-RNP and dsDNA play important roles in the immunopathological processes leading to the proliferative pulmonary arterial vasculopathy observed in CTD patients with pulmonary hypertension by up-regulating adhesion and class II MHC molecule expression on endothelial cells.

Terfenadine and fexofenadine reduce in vitro ICAM-1 expression on human continuous cell lines

BACKGROUND

Epithelial cells and fibroblasts play an important role in allergic inflammation. Modulation of surface expression of adhesion molecules on epithelial cells by antiallergic drugs has been shown by both in vivo and in vitro studies.

OBJECTIVE

The aim of the study was to evaluate the effect exerted by terfenadine and fexofenadine on adhesion molecules expression (CD54/ICAM-1 and CD29) of a human continuously cultured conjunctival epithelial cell line (WK) and a fibroblast cell line (HEL).

METHODS

By means of flow cytometry analysis, we evaluated ICAM-1 and CD29 expression by WK and HEL epithelial cells in basal condition (at baseline) or after IFN gamma or TNF alpha stimulation in the presence or in the absence of terfenadine and fexofenadine. We also performed immunoenzymatic assays in order to evaluate soluble ICAM-1 released by WK cells and procollagen type I and III and IL6 released by HEL cells.

RESULTS

Terfenadine and fexofenadine significantly reduced ICAM-1 basal expression on WK cells at the concentration of 1 microg/mL and 50 microg/mL, respectively. In addition, both terfenadine and fexofenadine were able to decrease soluble ICAM-1 levels in IFN gamma-stimulated WK cells. On HEL fibroblasts, fexofenadine only was able to inhibit ICAM-1 upregulation induced by IFN gamma. Concerning the release of fibroblast products, we observed a dose-dependent decrease of spontaneous IL6 release only in the presence of fexofenadine.

CONCLUSION

This study shows that terfenadine and fexofenadine exert a biologic effect directly on epithelial cells and fibroblasts reducing ICAM-1 expression and partially reducing soluble ICAM-1 release.

Downregulation of the expression of intercellular adhesion molecule (ICAM)-1 on bronchial epithelial cells by fenoterol, a beta2-adrenoceptor agonist

Inflammatory airway disorders, such as asthma and chronic bronchitis, are characterized by overexpression of adhesion molecules on airway epithelial and endothelial cells. This phenomenon is associated with increased adherence and activation of polymorphonuclear leukocytes (PMNs). With the knowledge that beta2-adrenoceptor agonists demonstrate some anti-inflammatory activity in vitro, the present study was designed to evaluate whether fenoterol could interfere with adhesion molecule expression on airway epithelium. Human bronchial epithelial cells (HBECs), obtained by protease digestion from surgically resected bronchi, were stimulated with human recombinant interferon-gamma (rh IFN-gamma) in the presence of (a) fenoterol (10(-12)-10(-5) M); (b) dexamethasone (10(-12)-10(-5) M); and (c) fenoterol and dexamethasone. Because desensitization after high-dose exposure to agonists has been described for many membrane-associated receptors, in additional sets of experiments HBECs were preexposed to fenoterol and, as control, to dexamethasone for 8 hr, then washed and stimulated with rh IFN-gamma in the presence of fresh drugs. The cells were harvested after 24-hr culture and stained by specific monoclonal antibodies. The intensity of intercellular adhesion molecule-1 (ICAM-1) expression was then measured by flow cytometry analysis and expressed as mean fluorescence channel (mfc). The significant increase in ICAM-1 expression on HBECs induced by rh IFN-gamma was inhibited, in a dose-dependent manner, by the two drugs, but fenoterol was more efficient than dexamethasone at all of the concentrations tested (p < 0.05, all comparisons). In addition, the inhibitory activity of fenoterol was not enhanced by the simultaneous presence of dexamethasone in rh IFN-gamma-stimulated HBEC cultures (p > 0.05, all comparisons). Finally, preexposure to fenoterol or to dexamethasone did not induce any modification of the inhibitory effect of the two drugs on ICAM-1 expression (p > 0.05, all comparisons). These results suggest that clinical efficacy of fenoterol in patients with obstructive lung disease may include downregulation of adhesion molecule expression on airway epithelial cells.

Novel antiallergic and antiinflammatory agents. Part II: Synthesis and pharmacology of TYB-2285 and its related compounds

A series of m-bis(glycoloylamino)benzene derivatives was synthesized by treatment of the corresponding m-diaminobenzene derivatives with glycoloyl chloride derivatives in pyridine. Hydrolysis of acetyl compounds gave hydroxy derivatives, from which other acyl derivatives could be synthesized. These compounds were tested in the rat PCA (passive cutaneous anaphylaxis) assay by oral administration. Benzonitrile derivatives (4c, 5c, 6c, 4h, 5h) exhibited notable inhibition in this assay. Compounds 5c and 6c also showed remarkable inhibition of eosinophil adhesion to TNF- (tumor necrosis factor) alpha-treated HUVEC (human umbilical vein endothelial cells) in the range of 10(-8)-10(-5) M. Compound 5c is now under investigation in Japan as TYB-2285 (Figure 1) for asthma and atopic dermatitis in phase II clinical studies.

Novel antiallergic and antiinflammatory agents. Part I: Synthesis and pharmacology of glycolic amide derivatives

A series of mono-glycoloylamino derivatives was synthesized by treatment of the corresponding aromatic monoamine derivatives with glycoloyl chloride derivatives in pyridine or dichloromethane, in the presence of a base such as triethylamine or pyridine. Hydrolysis of acetoxy compounds in aqueous ammonia and methanol solution produced hydroxy derivatives with ease. These compounds were tested in the rat PCA (passive cutaneous anaphylaxis) assay by oral administration. Thiazole and thiadiazole derivatives showed moderate inhibition in this assay. In contrast, benzothiazole and benzonitrile derivatives exhibited marked inhibition. In particular, compound 5t also showed marked inhibition of eosinophil adhesion to TNF (tumor necrosis factor) -alpha-treated HUVEC (human umbilical vein endothelial cells) in the range of 10(-8)-10(-5) M.

A placebo-controlled trial of ICAM-1 antisense oligonucleotide in the treatment of Crohn's disease

BACKGROUND & AIMS

Intercellular adhesion molecule 1 (ICAM-1) plays an important role in the trafficking and activation of leukocytes and is up-regulated in inflamed mucosa in Crohn's disease. ISIS 2302 is an antisense phosphorothioate oligodeoxynucleotide that inhibits ICAM-1 expression. The aim of this study was to obtain preliminary assessment of tolerability, pharmacology, and efficacy of ISIS 2302 in Crohn's disease.

METHODS

Twenty patients with active, steroid-treated Crohn's disease were randomized (3:1, ISIS 2302 to placebo) to receive over 26 days 13 intravenous infusions of ISIS 2302 (0.5, 1, or 2 mg/kg) or saline placebo in a double-blinded study. The patients were followed up for 6 months.

RESULTS

At the end of treatment. 47% (7 of 15) of ISIS 2302-treated and 20% (1 of 5) of the placebo-treated patients were in remission (Crohn's Disease Activity Index [CDAI] < 150). At the end of month 6, 5 of these 7 ISIS 2302-treated remitters were still in remission, and a 6th patient had a CDAI of 156. Corticosteroid usage was significantly lower (P = 0.0001) in the ISIS 2302-treated patients. These findings were corroborated by significant increases in beta7 and alpha d bearing CD3+ peripheral blood lymphocytes and by decreases in intestinal mucosal ICAM-1 expression during the treatment period.

CONCLUSIONS

ISIS 2302 seems to be a well-tolerated and promising therapy for steroid-treated Crohn's disease.

Pulmonary eosinophilia associated with increased airway responsiveness in young racing horses

Horses are known to acquire small airway disease (SAD), an allergen-induced naturally occurring syndrome of reversible obstructive lung disease accompanied by airway hyperresponsiveness and increased inflammatory cell numbers on bronchoalveolar lavage (BAL). This disorder has received scant attention in young racehorses. The purpose of the present report was to examine the effect of BAL eosinophilia in young racehorses on clinical examination, BAL, hematology, airway responsiveness, and on pulmonary function at rest and after a standardized exercise challenge. Five (3 males, 2 females; age 2.6 +/- 0.9 years) with a history of respiratory compromise and BAL eosinophil differential count > 5% and 6 controls (4 males, 2 females; age 3.5 +/- 1.0 years) training and performing to expectation with normal BAL cell differential (eosinophils < 1%) were studied. Respiratory system clinical examination was performed and expressed as a clinical score. Arterial blood gas measurements, CBC, and pulmonary function testing were performed at rest. Pulmonary mechanics measurements were repeated 1 hour and 20 hours after a standardized treadmill exercise challenge. Incremental histamine inhalation challenge was performed and the concentration of histamine effecting a 35% decrease in dynamic compliance (PC35CDyn) was determined. Significant differences were noted between and controls with regard to clinical score (P = .01), blood eosinophils (P = .04), BAL cell count (P = .04), BAL macrophage differential (P = .04), PC35CDyn (P = .008), and tidal volume and respiratory rate at 20 hours following exercise challenge (P = .05). We conclude that pulmonary eosinophilia and airway hyperresponsiveness are manifest in some young horses without overt airway obstruction at rest. We speculate that these may be early events in the natural progression of heaves.

Circulating adhesion molecules in cystic fibrosis

A marked influx of inflammatory cells occurs into the airways of patients with cystic fibrosis (CF), which may contribute to the development of lung injury. Leukocyte-endothelial adhesion molecules play a crucial role in the recruitment of inflammatory cells, and soluble forms of these molecules have been shown to increase in several inflammatory diseases. By using a capture ELISA, we determined serum levels of soluble ICAM-1 (sICAM-1), E-selectin (sE-selectin), and VCAM-1 (sVCAM-1) in patients with CF, in stable clinical conditions (n = 29, mean age: 25.8+/-1.5 yr), and healthy control subjects (n = 12, mean age: 27.6+/-1.5 yr). Clinical, spirometric, microbiological, and hematological assessments were made in all subjects. sICAM-1 and sE-selectin concentrations, but not sVCAM-1 levels were significantly increased in CF patients as compared with normal subjects (both p < 0.001). sICAM-1 levels were inversely related to FEV1 values (r = -0.519, p = 0.004) and Schwachman score (r = -0.405, p = 0.03) in CF patients. In 7 of 29 CF patients, soluble adhesion molecule levels were determined not only at the time of stable clinical conditions, but also before and after antibiotic treatment for a pulmonary exacerbation. sICAM-1 and sE-selectin levels increased in all patients at the time of the exacerbation, compared with levels at the time of stable conditions (p < 0.02 for both comparisons); antibiotic treatment induced a significant decrease of both circulating adhesion molecules (p < 0.02). The elevated serum levels of sICAM-1 and sE-selectin in CF patients, even when they are clinically stable, may reflect the marked and persistent inflammatory process in the disease.

Smoking alters the phenotype of macrophages in induced sputum

To investigate the effect of chronic smoke exposure on pulmonary macrophages (PM), the expression of seven different surface and intracellular molecules of PM was studied in induced sputum (IS) samples from healthy volunteers--nine smokers and seven non-smokers. Sputum was induced by inhalation of nebulized saline (3.5% NaCl). Cell viability and total cell counts (TCC) were performed immediately. Cell differentials were determined on May-Grunwald Giemsa-stained cytospin preparations. The PM were immunologically characterized by use of the following monoclonal antibodies: RFD1, RFD7, CD11b, CD54, CD68, CD71 and HLA-DR. The stainings were performed with a three-step, indirect immuno-alkaline phosphate method. Viability and TCC did not differ between the groups. Smokers had a higher percentage of macrophages (P < 0.05) and a lower proportion of neutrophils (P < 0.05). The percentage of macrophages expressing RFD1, HLA-DR, CD71 (P < 0.01 for all) and CD54 (P < 0.05) was significantly lower in smokers, whereas the remaining markers were expressed equally in the two groups. The results indicate that smoking induces a decrease in the expression by PM of surface molecules known to be associated with the antigen-presenting function.

Changes of soluble ICAM-1 levels in serum and bronchoalveolar lavage fluid from patients with atopic bronchial asthma after allergen challenge

Leukocyte-endothelial cell interaction is essential for leukocyte infiltration into inflammatory sites. Initiation of adhesion is through the up-regulated expression of adhesion molecules in the endothelium or epithelium and the activation of adhesion molecules on leukocytes. To our knowledge, there have been few reports concerning soluble intercellular adhesion molecule-1 (sICAM-1) in patients with atopic bronchial asthma after allergen challenge. If the levels of sICAM-1 vary between bronchial asthma patients and normal controls, this variance would be useful to assess the state of this disease. Therefore, we measured the levels of sICAM-1 in sera from 17 patients with atopic bronchial asthma and normal control subjects. Levels of sICAM-1 in sera from bronchial asthma patients in prechallenge conditions were higher than in normal control subjects. Levels of sICAM-1 in sera from bronchial asthma patients 8 hr after challenge were higher than those in sera obtained during prechallenge periods. sICAM-1 levels in bronchoalveolar lavage (BAL) fluids from bronchial asthma patients 8 hr after challenge were higher than at 30 min after challenge. These results suggest that higher levels of sICAM-1 in sera and BAL fluids reflect the up-regulation of ICAM-1 expression in allergic bronchial asthma and these high levels may contribute to the pathogenesis of atopic bronchial asthma.

Inhibition of adhesion molecules by budesonide on a human epithelial cell line (lung carcinoma)

Inhaled corticosteroids in the treatment of asthma have been shown to produce marked reductions in the number of inflammatory cells (mainly mast cells and eosinophils) and their products at bronchial level (such as cytokines). Recently, it has been demonstrated that epithelial cells express ICAM-1/CD54 in allergic patients both during natural allergen exposure and after allergen challenge. We have previously demonstrated that deflazacort (a systemic steroid) reduces the expression of ICAM-1 on conjunctival epithelial cells. The present study aimed to evaluate the effects exerted by budesonide on adhesion molecule expression by a human epithelial cell line (lung carcinoma: DM) and on soluble ICAM-1. Budesonide was added at concentrations corresponding to 10(-8), 10(-7), and 10(-6) mol/l in cultured epithelial cells, either in the absence of any stimulus or in the presence of interferon-gamma (IFN-gamma) at 500 U/ml. After 24 h of incubation, cytofluorometric analysis was performed for ICAM-1 and CD29/VLA beta 1. The 24-h supernatants of the same cultures were collected and then evaluated for soluble ICAM-1 (sICAM-1). The results showed that budesonide inhibits ICAM-1 and CD29 basal expression on the cells studied (P < 0.05): budesonide was effective in a dose-dependent manner. In addition, budesonide reduced surface ICAM-1 upregulation induced by IFN-gamma at 500 U/ml (P < 0.05). Finally, cell cultures with budesonide showed decreased levels of soluble ICAM-1 in basal condition, but not after IFN-gamma stimulation.

Intercellular adhesion molecule-1 on cultured human epithelial cell lines: influence of proinflammatory cytokines

The expression of intercellular adhesion molecule-1 (CD54 or ICAM-1) on epithelial cells during acute or chronic inflammation may favor the interaction between epithelial cells and leukocytes expressing the natural ligands of ICAM-1, LFA-1 (CD11a/CD18), and Mac-1 (CD11b/CD18). We have evaluated in vitro the expression of ICAM-1 by a conjunctival (WK) and an intestinal (I407) human continuous epithelial cell line. Cells were cultured for 24 h in the presence or absence of IFN-gamma, TNF-alpha, IL-1 beta, IL-4, IL-6, IL-8, IL-10, and TGF-beta 1. Both epithelial cell lines showed a constitutive expression of ICAM-1. IFN-gamma at 500 U/ml and TNF-alpha at 200 ng/ml upregulated ICAM-1 expression; IL-1 beta at 100 pg/ml upregulated ICAM-1 on WK cells only. Cells cultured in the presence of both IFN-gamma and TNF-alpha exhibited a mean fluorescence intensity far greater than those cultured with IFN-gamma or TNF-alpha alone. I407 and WK cells were able to release soluble ICAM-1. IFN-gamma and TNF-alpha enhanced the release of sICAM-1. IL-4, IL-6, IL-8, IL-10, and TGF-beta 1 did not affect either ICAM-1 expression or sICAM-1 release. In conclusion, continuously cultured human epithelial cells may express ICAM-1 on their surface and release it in culture medium. These phenomena are upregulated by proinflammatory cytokines.