Xanthine oxidase inhibition reduces reactive nitrogen species production in COPD airways.

Reactive nitrogen species (RNS) have been reported to be involved in the inflammatory process in chronic obstructive pulmonary disease (COPD). However, there are no studies on the modulation of RNS in COPD. It was hypothesised that inhibition of xanthine oxidase (XO) might decrease RNS production in COPD airways through the suppression of superoxide anion production. Ten COPD and six healthy subjects participated in the study. The XO inhibitor allopurinol (300 mg x day(-1) p.o. for 4 weeks) was administered to COPD patients. RNS production in the airway was assessed by 3-nitrotyrosine immunoreactivity and enzymic activity of XO in induced sputum as well as by exhaled nitric oxide (eNO) concentration. XO activity in the airway was significantly elevated in COPD compared with healthy subjects. Allopurinol administration to COPD subjects significantly decreased XO activity and nitrotyrosine formation. In contrast, eNO concentration was significantly increased by allopurinol administration. These results suggest that oral administration of the xanthine oxidase inhibitor allopurinol reduces airway reactive nitrogen species production in chronic obstructive pulmonary disease subjects. This intervention may be useful in the future management of chronic obstructive pulmonary disease.     

Soluble TNF-alpha receptor and IL-1 receptor antagonist elevation in BAL in active pulmonary TB.

Accumulating evidence suggests that patients with active pulmonary tuberculosis (TB) have an alveolar inflammation resulting in the release of tumour necrosis factor (TNF)-alpha and interleukin (IL)-1beta in bronchoalveolar epithelial fluid. It was proposed that the levels of these cytokines would correlate with clinical status parameters (extent of pulmonary involvement, fever, and body weight loss) and that their naturally occurring inhibitors would be concomitantly released in the local inflammatory sites. To test this hypothesis lung epithelial lining fluid (ELF) obtained by bronchoalveolar lavage and serum were collected from 29 patients with active pulmonary TB and 15 healthy subjects to determine the levels of these variables using a sandwich enzyme-linked immunosorbent assay (ELISA). ELF levels of TNF-alpha, soluble (s)TNF receptor I (RI), sTNF-receptor II (RII) and interleukin-1 receptor antagonist (IL-1RA) but not IL-1beta, and their serum levels except for sTNF-RII and IL-1beta were significantly higher in TB patients. Nevertheless, only ELF levels of TNF-alpha and IL-1beta were significantly correlated with disease status. No correlation was found between TNF-alpha levels and those of sTNF-RI and sTNF-RII, nor between IL-1beta and IL-1RA in ELF and serum of TB patients, although there was a significant correlation between sTNF-RI and sTNF-RII levels both in ELF and serum. These findings suggest local release of tumour necrosis factor-alpha and interleukin-1beta and a correlation with disease status. Soluble tumour necrosis factor-alpha receptors and interleukin-1beta receptor antagonist, although increased in lung epithelial lining fluid and serum in tuberculosis patients, were not correlated with tumour necrosis factor-alpha and interleukin-1beta or with disease status.     

Immune activation and nutritional status in adult Crohn''s disease patients

BACKGROUND: Recent attention focused on the effect of inflammatory cytokines on intermediary metabolism contributing to the nutritional disturbances observed in acute or chronic inflammatory diseases. AIMS: To examine the interactions between immune activation and nutritional parameters in adult Crohn's disease patients. PATIENTS AND METHODS: We analysed anthropometric and biochemical nutritional parameters in 40 Crohn's disease patients and 26 healthy controls, and related them to inflammatory and immune markers. RESULTS: Weight, body mass index, mid-arm circumference, triceps skinfold thickness, as well as albumin, transthyretin, retinol binding protein, insulin growth factor-I and Vitamin A were significantly decreased in Crohn's disease patients and negatively correlated to disease activity. By contrast, erythrocyte sedimentation rate, fibrinogen, C-reactive protein, alpha1-acylglycoprotein, soluble receptor of interleukin-2, blood neopterin, tumour necrosis factor-alpha and interleukin-1beta concentrations were significantly higher in patients and positively correlated to disease activity. Nutritional parameters and acute phase reactants were linked to tumour necrosis factor-alpha and interleukin-1beta concentrations, and markers of nutritional status were negatively correlated to positive acute phase reactants. CONCLUSIONS: In Crohn's disease, inflammatory cytokines appear partly responsible for decreased nutritional status. Thus, nutritional intervention to correct nutritional (in particular protein) depletion, and/or therapeutic intervention reducing inflammation and therefore restoring adequate nutritional proteins synthesis, appears a major therapeutic goal in active Crohn's disease.     

Granulocyte inflammatory markers and airway infection during acute exacerbation of chronic obstructive pulmonary disease

There is increasing evidence that chronic obstructive pulmonary disease (COPD) is associated with chronic inflammation in the airways and lung parenchyma; however, little is known about the inflammatory response during acute COPD exacerbation. The objectives of this study were (1) to determine if inflammatory markers associated with neutrophilic inflammation and activation increase at times of acute COPD exacerbation relative to the clinically stable state, and (2) to determine whether the presence of acute bacterial or viral infection at the time of COPD exacerbation could be correlated with increases in sputum markers of inflammation. Induced sputum was collected from patients with COPD when they were clinically stable, during the time of an acute exacerbation, and 1 mo later. Sputum was analyzed at each time point for soluble markers associated with neutrophilic inflammation; myeloperoxidase (MPO), tumor necrosis factor-alpha (TNF-alpha), and interleukin-8 (IL-8). Serologic assays on acute and convalescent sera were performed for respiratory viruses, and induced sputum was also subject to quantitative bacterial cultures, viral cultures, and polymerase chain reaction (PCR) for detection of respiratory viruses. Fourteen of the 50 patients enrolled in the study met predetermined criteria for an acute COPD exacerbation over the 15-mo study period. TNF-alpha and IL-8 were significantly elevated in the sputum of patients during acute COPD exacerbation compared with when they were clinically stable (p = 0.01 and p = 0.05, respectively). Concentrations of these cytokines declined significantly 1 mo after the exacerbation. Three of 14 patients (21%) had confirmed bacterial or viral respiratory tract infections. Patients with documented infection did not demonstrate greater increases in sputum levels of inflammatory cytokines during exacerbations compared with patients without demonstrable infection. We conclude that markers of airway neutrophilic inflammation increase at the time of acute COPD exacerbation and then decline 1 mo later, and that this acute inflammatory response appears to occur independently of a demonstrable viral or bacterial airway infection.     

Role of pro-/anti-inflammatory cytokines and their correlation with established risk factors in South Indians with coronary artery disease

Cytokines are responsible for the modulation of immunological and inflammatory processes and play a significant role in the pathogenesis of coronary artery disease. We estimated the levels of pro-/anti-inflammatory cytokines in South Indian patients with coronary artery disease. The study population comprised of groups 1-3: 100 patients each with acute myocardial infarction, unstable angina, and stable angina, respectively, and group 4 (100 healthy controls). Cytokine levels (interleukin-6, interleukin-8, interleukin-10, and tumor necrosis factor-alpha) were estimated by enzyme-linked immunosorbent assay (ELISA). Interleukin-6, interleukin-8, and tumor necrosis factor-alpha levels were significantly higher in patients from groups 1 and 2, than in group 3 and controls. Acute myocardial infarction patients exhibited higher serum levels of interleukin-10 compared with other groups and control subjects. Patients with unstable angina had significantly lower interleukin-10 concentrations than those with stable angina. The ratios of pro-/anti-inflammatory cytokines in all the study groups increased significantly when patients with unstable angina were compared to other groups. In patients with acute myocardial infarction, interleukin-10 and tumor necrosis factor-alpha levels showed significant correlation with established risk factors such as body mass index, blood pressure, and lipid levels. Acute myocardial infarction patients show elevation in proinflammatory and anti-inflammatory cytokines, while unstable angina is associated with low levels of serum interleukin-10. Higher levels of anti-inflammatory cytokine interleukin-10 may be needed to provide protection in unstable angina. These cytokines are markers of coronary artery disease and may be used for the identification of high-risk patients with unstable angina/acute myocardial infarction.     

Patients with chronic idiopathic neutropenia of adults have increased serum concentrations of inflammatory cytokines and chemokines

Serum levels of inflammatory cytokines and chemokines were measured in 132 patients with chronic idiopathic neutropenia of adults (CINA) and 34 healthy volunteers (controls) using commercially available micro-ELISA determination kits. We found that serum interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), transforming growth factor-beta(1) (TGF-beta(1)), and soluble tumor necrosis factor receptor p55 (sTNF-RI) were all significantly increased in CINA patients compared to controls. Individual cytokine values inversely correlated with the number of circulating neutrophils. Serum levels of interleukin-8 (IL-8) and RANTES, two potent chemokines for neutrophils and lymphocytes, respectively, were also significantly increased in the group of patients and they inversely correlated with the number of circulating neutrophils. Contrarily, serum levels of interleukin-4 (IL-4), interferon-gamma (IFN-gamma), soluble CD23 (sCD23), and soluble interleukin-2 receptor (sIL-2R) did not show any significant change in the patients studied. We assume that CINA patients have increased serum concentrations of inflammatory cytokines and chemokines mainly produced by activated macrophages, while they disclose normal levels of inflammatory molecules mainly released from activated lymphocytes. These findings provide further evidence for an underlying low-grade chronic inflammatory process in CINA patients, as we previously have suggested. If this chronic inflammation is really the cause of the disorder or it simply represents the result of neutropenia remains to be elucidated.     

Tumour necrosis factor-alpha potentiates contraction of human bronchus in vitro

OBJECTIVE: Chronic inflammation of the airways is an important component in the induction of airway hyperresponsiveness (AHR) in asthma. The pro-inflammatory cytokines interleukin-1beta (IL-1beta) and tumour necrosis factor-alpha (TNF-alpha) have been implicated in the induction of AHR. Whether these cytokines directly modulate the contractile properties of human airway smooth muscle (ASM) has not been fully investigated. METHODOLOGY: The contractile response to acetylcholine (ACh) (10(-8) to 10(-3) mol/L) was determined in isolated human bronchial segments both prior to and following a 16-h incubation period with IL-1beta (10 or 20 ng/mL) and TNF-alpha (25 ng/mL), either alone or in combination. Incubation of human bronchial segments with IL-1beta/TNF-alpha was also performed in the presence of the COX-1/COX-2 inhibitor, indomethacin. RESULTS: Tumour necrosis factor-alpha potentiated the contractile response to ACh by approximately 27%, while IL-1beta or the cytokines in combination had no effect. Indomethacin had no modulatory effect on the contractile response to ACh in the cytokine-treated tissues. CONCLUSIONS: The relative concentrations of IL-1beta/TNF-alpha in the vicinity of ASM may ultimately determine their effects on ASM contraction in asthma.     

Effect of interleukin-1beta and tumor necrosis factor-alpha on the expression of G-proteins in CD4+ T-cells of atopic asthmatic subjects.

Chronic use of beta2-agonists and increased production of inflammatory mediators during the late allergic reaction after the antigen challenge result in the desensitization of beta-adrenoceptors in the airways with an accompanying rise in non-specific airway hyperresponsiveness. Several proinflammatory cytokines, including interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), play a significant role in orchestrating and perpetuating the inflammatory response and induce the decreased response to bronchodilators in vitro. However, the underlying mechanisms are unknown. In this study, we examined the effect of two cytokines, IL-1beta and TNF-alpha, on the expression of guanine nucleotide binding regulatory proteins (G-proteins), Gs alpha and Gi alpha-3, by Western blotting in the CD4+ cells of nonatopic nonasthmatic (NANA), atopic nonasthmatic (ANA), and atopic asthmatic (AA) subjects. In the purified CD4+ cells, the basal expression of Gs alpha was higher in the ANA group, and significantly lower in the AA group as compared to the NANA group. The basal expression of Gi alpha-3 was significantly greater (3-15 fold) than Gs alpha, with no significant difference between any of the three groups. Both cytokines IL-1beta and TNF-alpha significantly decreased the expression of Gs alpha in the CD4+ cells of the NANA and ANA groups, with no effect in the AA group. However, these cytokines increased the expression of Gi alpha-3, proteins in the AA group, but had no effect in the CD4+ cells of the NANA and ANA groups. These data suggest that a decreased response to beta2-agonists in the late allergic response in allergic asthmatic subjects could be due to the release of inflammatory cytokines, which induce a decrease in the stimulatory G-proteins and an increase in the inhibitory G-proteins.     

Effects of TNF-alpha, IFN-gamma and IL-beta on normal human bronchial epithelial cells.

Several diseases affecting the airways such as asthma are associated with both epithelial damage and increased levels of pro-inflammatory cytokines. To investigate the possible relation between cytokines and epithelial damage, the effects of tumour necrosis factor-alpha (TNF)-alpha, interferon gamma (IFN-gamma) and interleukin-1 beta (IL-1beta) on normal human bronchial epithelial cells in vitro were studied. The cells were exposed to these cytokines for 48 or 72 h, followed by morphological, immunohistochemical and metabolic studies. Transmission and scanning electron microscopical analyses demonstrated damage to the mitochondria and an increase in cell processes induced by the cytokines. The use of antibodies against desmosomal cytokeratin showed a decrease in desmosome formation in IFN-gamma-exposed cells. Decreased glucose oxidation rate and increased accumulation of nitric oxide were found in cytokine-exposed cells. Nomega-monomethyl-L-arginine (L-NMMA) reduced nitrite production. X-ray microanalysis showed an increase in the intracellular sodium/potassium ratio of the cells after exposure to cytokines, which is an indication of cell damage. The cytokines induced both necrosis and apoptosis to varying degrees. IFN-gamma and TNF-alpha generally potentiate each other's effects. In conclusion tumour necrosis factor-alpha and interferon gamma, and to a lesser extent interleukin-1beta, can cause damage to epithelial cells, which may be a factor involved in epithelial shedding in airway diseases.     

血清细胞因子及急性期反应蛋白与COPD患者抑郁情绪的相关分析

目的探讨血清细胞因子白介素1β（IL-1β）、白介素6（IL-6）、肿瘤坏死因子-α（TNF-α）和C反应蛋白（CRP）、结合珠蛋白（Hp）、转铁蛋白（Tf）等急性期反应蛋白与慢性阻塞性肺疾病（COPD）患者抑郁情绪的相关性。方法采用酶联免疫吸附法（ELISA）、散射速率比浊法测定健康对照者及COPD患者的血清IL-1β、IL-6、TNF-α、CRP、Hp、Tf水平。结果 1.COPD患者抑郁的发生率明显高于健康对照组（P〈0.05）;2.COPD对照组IL-1β、IL-6、TNF-α、Hp水平显著高于健康对照组,但较COPD伴抑郁情绪组明显偏低（P〈0.05）,各组间血清CRP测定则未发现统计学差别（P〉0.05）;3.不同抑郁程度的COPD患者,其血清IL-1β、IL-6、TNF-α、Hp、和Tf水平之差异具统计学意义（P〈0.05）;4.血清IL-1β、IL-6和Hp水平均与COPD抑郁的严重程度显著正相关,急性期反应蛋白Tf则与COPD抑郁程度呈负相关（P〈0.05）。结论慢性阻塞性肺疾病患者气道中存在大量炎性细胞,其释放的细胞因子及急性期反应蛋白在COPD患者抑郁情绪的发病机理中起着重要作用。     

Relation of plasma leptin to C-reactive protein in older adults (from the Invecchiare nel Chianti study)

Obese subjects have higher circulating levels of C-reactive protein (CRP) than normal subjects, and it has been shown that CRP per se may contribute to atherogenesis. The mechanism linking increased fat mass with high CRP levels has not been exhaustively explained. It has been suggested that adipose tissue-produced cytokines, including interleukin-6, tumor necrosis factor-alpha, and interleukin-1beta, represent the causal link between increased body fat and high CRP levels. It has been hypothesized that the hormone leptin, released by fat cells, may stimulate CRP production independent of cytokines. This study measured circulating leptin, CRP, interleukin-6, tumor necrosis factor-alpha, interleukin-1beta, and interleukin-8 in 946 community-dwelling older subjects (398 men, 548 women; age range 65 to 102 years) enrolled in a large population-based study. Confounders included demographics, functional, cognitive and affective status, diet and lifestyle, body composition, drugs, and chronic diseases. A direct association was found between leptin and CRP (p = 0.004), independent of cytokines and other possible confounders. The association was stronger in younger than in older subjects but was not influenced by gender or body mass index. In conclusion, these findings suggest that leptin may directly stimulate the production of CRP independent of fat-cell produced cytokines in older adults.     

Clara cell 10-KDA protein inhibits endotoxin-induced airway contraction in isolated perfused rat lungs

Clara cell 10-kDa protein (CC10) is a major component of bronchoalveolar lavage fluid and is suggested to be a natural regulator of airway inflammation, possibly through its effects on the proinflammatory enzyme(s), phospholipase A2. We examined the effect of recombinant human (rh) CC10 on endotoxin-induced airway contraction and cytokine release in isolated perfused rat lungs. We found that rhCC10 added to the lung perfusate abolished the endotoxin-induced airway contraction, and that it inhibited both the release of interleukin-1 beta and interleukin-6 into the lung perfusate and the release of tumor necrosis factor-alpha into the pulmonary lavage fluid. By contrast, the levels of interferon-gamma were unaffected by CC10 administration. Rutin, a phospholipase A2 inhibitor, and N omega-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, also attenuated the contraction induced by endotoxin. These findings demonstrate that rhCC10 inhibits endotoxin-induced airway contraction and the release of proinflammatory cytokines (interleukin-1 beta, interleukin-6, and tumor necrosis factor-alpha) in isolated perfused rat lungs. The results also indicate that phospholipase A2 and nitric oxide are involved in the airway contraction in this model, possibly through their influence on the production of eicosanoids.     

慢性阻塞性肺疾病稳定期慢性肺损伤的机制研究

目的通过检测稳定期不同级别慢性阻塞性肺疾病患者血清中氧化/抗氧化指标及细胞炎症因子水平与肺功能主要指标的关系,探讨血清氧化/抗氧化因子及细胞炎症因子水平的变化对肺功能的影响,从而明确COPD稳定期慢性肺损伤的机制。方法在呼吸科门诊筛查的COPD稳定期患者中选取80例,按照2011年《慢性阻塞性肺疾病诊治指南》标准分级,分成4组:Ⅰ级组、Ⅱ级组、Ⅲ级组、Ⅳ级组。检测用力肺活量(FVC)、1秒钟用力呼气容积(FEV1)、FEV1/FVC;用ELISA方法测定患者血清中氧化指标反应性氧核素(ROS)、氧化/抗氧化指标超氧化物歧化酶(SOD)及细胞炎症因子中的肿瘤坏死因子-α(TNF-α)、IL-8及粒-巨细胞集落刺激因子(GM-CSF)水平,观测各组的差异并分析其相关性。结果 FEV1、FVC、FEV1/FVC、SOD、ROS、TNF-α、IL-8、GM-CSF水平在不同组别中存在差异(P<0.05),且ROS、TNF-α、IL-8、GM-CSF水平与FEV1,FVC存在着明显的负相关(P<0.05),然而SOD与其存在明显正相关(P<0.05)。结论 COPD细胞炎症因子的持续升高及氧化加重可能是引起稳定期慢性阻塞性肺疾病肺组织慢性损伤、功能降低的重要原因。     

Effect of the p38 kinase inhibitor, SB 203580, on sephadex induced airway inflammation in the rat.

SB 203580 is a pyridinyl imidazole compound which inhibits the release of pro-inflammatory cytokines, such as tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta), in vitro and in vivo by inhibiting p38 mitogen-activated protein kinase (MAPK). The present study investigated the effects of SB 203580 in a model of airway inflammation induced by the topical administration of Sephadex into the rat airways. This inflammatory response is characterized by the development of lung oedema, airway tissue inflammatory cell recruitment and an increase in lung TNF-alpha and IL-1beta levels. Sephadex-induced lung oedema was accompanied by a significant increase in lung tissue TNF-alpha but not IL-1beta levels. There was also a significant increase in lung tissue macrophages and an increase in eosinophils which did not reach significance. SB 203580 administration significantly inhibited lung oedema (ED50=18 mg x kg(-1)) in a dose-related manner but was without significant effect on lung tissue cell recruitment or cytokine levels. These data suggest that the increase in tumour necrosis factor-alpha and lung oedema are separate processes which both contribute to Sephadex pathology. Furthermore, the inhibitory effect of SB 203580 on Sephadex-induced lung oedema suggests that p38 kinase inhibitors may be of use in pulmonary pathologies in which lung oedema is a feature.     

Nicotinamide inhibits enhanced in vitro production of interleukin-12 and tumour necrosis factor-alpha in peripheral whole blood of people at high risk of developing type 1 diabetes and people with newly diagnosed type 1 diabetes

Macrophages and T lymphocytes are the first cells to appear in pancreatic islets in the development of autoimmune diabetes. It has been suggested that cytokines released by monocytes/macrophages, including interleukin-1beta (IL-1beta), interleukin-12 (IL-12) and tumour necrosis factor-alpha (TNF-alpha) could have an initial role in islet B-cell damage. The aim of the present study was to estimate the effect of human insulin and nicotinamide on the levels of monocyte/ macrophage derived cytokines in the peripheral blood of humans at risk of Type 1 diabetes, and in patients with newly diagnosed Type 1 diabetes compared to healthy control subjects. The study was carried out on three groups of subjects: 20 first degree relatives of people with Type 1 diabetes (with two or more antibodies against pancreatic B-cell antigens); 22 patients with recent onset of Type 1 diabetes (duration of the disease 3-6 months); and 25 age- and sex-matched healthy subjects. Cytokine levels (IL-1beta, IL-12, and TNF-alpha) in the supernatants of whole blood cultures incubated with PHA alone (10 microg/ml), or PHA + human insulin (50 microg/ml), or PHA + nicotinamide (100 micromol/l) were quantified by ELISA. In the cultures with nicotinamide the concentration of IL-12 and TNF-alpha was significantly lower in the prediabetic group, diabetic patients, and the healthy controls than in the cultures with PHA only or with PHA + insulin. There were no significant differences in IL-1beta production in the cultures after incubation with the different stimuli in the studied groups and healthy controls. No significant influence of human insulin on macrophage/monocyte cytokines secretion in in vitro cultures of the peripheral blood was found. This suggests that nicotinamide could influence monocyte/macrophage function in peripheral blood by inhibiting production of IL-12 and TNF-alpha.     

Inhaled Fluticasone and Salmeterol Suppress Eosinophilic Airway Inflammation in Chronic Obstructive Pulmonary Disease: Relations with Lung Function and Bronchodilator Reversibility

The aim of this study was to determine whether combined inhaled corticosteroids and long-acting β₂ agonists can suppress eosinophilic inflammation in chronic dostructive plumonary disease (COPD) and to investigate the association between the level of eosinophilia and the degree of bronchodilator reversibility. Sixty-two patients with stable COPD (forced expiratory volume in 1 [FEV₁] of 30%–70% predicted before bronchodilation) were enrolled from our outpatient clinic. Patients received inhaled fluticasone (100 μg)/salmeterol (50 μg) twice daily for two months. Lung function measurements, bronchodilator tests, and sputum induction were performed. The number of inflammatory cells and mediators, including interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α), and eosinophilic cationic protein (ECP), were measured. Treatment with inhaled fluticasone and salmeterol significantly suppressed eosinophilic inflammation in COPD patients with sputum eosinophilia (mean 8.9% ± 2.0% vs. 1.6% ± 0.5%, p = 0.003), but insignificant differences in FEV₁ and FVC between patients with and without eosinophilia suggested that suppression of eosinophilic inflammation had no effect on FEV₁ or FVC. Reduction in the percentage of eosinophils was significantly correlated with decreased levels of ECP (r = 0.48, p < 0.001). Levels of neutrophils, IL-8, and TNF-α were not affected. Sputum eosinophilia was not related to the degree of bronchodilator reversibility. The degree of bronchodilator reversibility did not predict the increase in FEV₁ and FVC after treatment with inhaled corticosteroids/long-acting β₂ agonists. Suppression of eosinophilic inflammation and bronchodilator responsiveness indices were not correlated with clinical outcomes in COPD patients treated with inhaled corticosteroids/long-acting β₂ agonists. Diahn-Warng Perng and Cheng-Che Wu contributed equally to this work.     

Inflammatory cytokines modulate eotaxin release by human lung fibroblast cell line

Eotaxin, a potent eosinophil-specific chemotactic factor, is increased in the lower respiratory tract of asthma patients. Recently, lung fibroblasts have been reported to produce eotaxin and their activation can be modulated by inflammatory cytokines. To test the hypothesis that inflammatory cytokines modulate the eotaxin release from lung fibroblasts, we investigated the potential of interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), or interferon-gamma (IFN-gamma) to induce the release of eotaxin and eotaxin mRNA by the human fetal lung fibroblast cell line, HFL-1, was evaluated. HFL-1 released eotaxin constitutively without stimulation, but IL-1beta or TNF-alpha stimulated eotaxin release in a dose- and time-dependent manner. IL-1beta or TNF-alpha treatment of HFL-1 also resulted in the augmented expression of eotaxin mRNA. Although IFN-gamma alone had negligible effect on eotaxin release and mRNA expression, IFN-gamma induced a significant, concentration-dependent attenuation of eotaxin release and eotaxin mRNA expression from HFL-1 stimulated with IL-1beta or TNF-alpha. These findings are consistent with the concept that lung fibroblast-derived eotaxin may in part be responsible for the eosinophil infiltration observed in the airways of asthmatic patients and that network of cytokines may modulate the eosinophil recruitment to the airways by stimulation of fibroblasts to release eotaxin.     

Effects of a hydrosoluble bacterial extract from Escherichia coli (OM-89) on cytokine production by peripheral blood mononuclear cells from healthy subjects and patients with rheumatoid arthritis

OM-89 is a bacterial extract from escherichia coli, proposed as an immunomodulating drug for the treatment of rheumatoid arthritis (RA). Since immunological mechanisms may play a role in its action, the immunological effects of OM-89 were evaluated in vitro on peripheral blood mononuclear cells (PBMC) derived from healthy subjects and RA patients. Results indicated that in the absence of OM-89, production of the monokines interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) is increased, while that of the lymphokines interleukin-2 (IL-2) and interferon-gamma (IFN-gamma is decreased by phytohemagglutinin (PHA)-stimulated PBMC from RA patients as compared with PBMC from healthy subjects. In the presence of PHA, OM-89 enhanced the production of IL-1 beta, TNF-alpha, IL-2, and IFN-gamma. IL-1 beta and IL-2 curves obtained using increasing amounts of OM-89 did not differ depending on the source of PBMC. By contrast, in the presence of increasing amounts of OM-89, TNF-alpha secretion significantly higher and IFN-gamma secretion significantly lower with PBMC from RA patients compared to PBMC from healthy subjects. These data indicate that OM-89 acts on monocytes and T cells directly and/or indirectly and suggest a possible clinical activity by OM-89 in RA relative to its immunological properties.