Nasal lavage cytokines in normal, allergic, and asthmatic school-age children

The Impact of Cytokines on Health-Related Quality of Life in Adolescents with Allergic Rhinitis

BACKGROUND

Frequent episodes of nasal symptoms are the usual clinical manifestations (CM) of allergic rhinitis (AR) and have a significant negative impact on health-related quality of life (HRQoL) in adolescents. The purpose of this cross-sectional study was to test the hypothesis that cytokines in nasal mucus may be associated with HRQoL in adolescents with AR.

METHODS

European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L), "The Adolescent Rhinoconjunctivitis Quality of Life Questionnaire" (AdolRQLQ) and the Total 4 Symptom Score (T4SS) scoring system were administered to 113 adolescents with AR, nonallergic rhinitis (NAR) and to healthy control subjects. Nasal secretions were sampled and tested for 13 cytokines using a multiplex flow cytometric bead assay.

RESULTS

The AR group had significantly lower EQ-5D-3L (0.661 ± 0.267 vs. 0.943 ± 0.088; p < 0.001) and higher AdolRQLQ total scores (2.76 ± 1.01 vs. 1.02 ± 0.10; p < 0.001) compared to the control group. The AR group had higher concentrations of IL-1β (p = 0.002), IL-6 (p = 0.031), IL-8 (p < 0.001), IL17-A (p = 0.013) and IL-18 (p = 0.014) compared to the control group, and IL-1β, IL-6, IL17-A and IL-18 were significantly (p < 0.050) increased with disease progression. Cytokines IL-1β, IL-6, as well as severe CM, were identified as significant predictors of lower HRQoL in adolescents with AR.

CONCLUSIONS

This study identified IL-1β, IL-6, as well as severe CM, as predictors of lower HRQoL in adolescents with AR. However, these results should only serve as a starting point for additional confirmation research.

Mechanisms and biomarkers of airway epithelial cell damage in asthma: A review

Bronchial asthma is a heterogeneous disease with complex pathological mechanisms representing different phenotypes, including severe asthma. The airway epithelium is a major site of complex pathological changes in severe asthma due, in part, to activation of inflammatory and immune mechanisms in response to noxious agents. Current imaging procedures are unable to accurately measure epithelial and airway remodeling. Damage of airway epithelial cells occurs is linked to specific phenotypes and endotypes which provides an opportunity for the identification of biomarkers reflecting epithelial, and airway, remodeling. Identification of patients with more severe epithelial disruption using biomarkers may also provide personalised therapeutic opportunities and/or markers of successful therapeutic intervention. Here, we review the evidence for ongoing epithelial cell dysregulation in the pathogenesis of asthma, the sentinel role of the airway epithelium and how understanding these molecular mechanisms provides the basis for the identification of candidate biomarkers for asthma prediction, prevention, diagnosis, treatment and monitoring.

Allergen inhalation generates pro-inflammatory oxidised phosphatidylcholine associated with airway dysfunction

Oxidised phosphatidylcholines (OxPCs) are produced under conditions of elevated oxidative stress and can contribute to human disease pathobiology. However, their role in allergic asthma is unexplored. The aim of this study was to characterise the OxPC profile in the airways after allergen challenge of people with airway hyperresponsiveness (AHR) or mild asthma. The capacity of OxPCs to contribute to pathobiology associated with asthma was also to be determined.Using bronchoalveolar lavage fluid from two human cohorts, OxPC species were quantified using ultra-high performance liquid chromatography-tandem mass spectrometry. Murine thin-cut lung slices were used to measure airway narrowing caused by OxPCs. Human airway smooth muscle (HASM) cells were exposed to OxPCs to assess concentration-associated changes in inflammatory phenotype and activation of signalling networks.OxPC profiles in the airways were different between people with and without AHR and correlated with methacholine responsiveness. Exposing patients with mild asthma to allergens produced unique OxPC signatures that associated with the severity of the late asthma response. OxPCs dose-dependently induced 15% airway narrowing in murine thin-cut lung slices. In HASM cells, OxPCs dose-dependently increased the biosynthesis of cyclooxygenase-2, interleukin (IL)-6, IL-8, granulocyte-macrophage colony-stimulating factor and the production of oxylipins via protein kinase C-dependent pathways.Data from human cohorts and primary HASM cell culture show that OxPCs are present in the airways, increase after allergen challenge and correlate with metrics of airway dysfunction. Furthermore, OxPCs may contribute to asthma pathobiology by promoting airway narrowing and inducing a pro-inflammatory phenotype and contraction of airway smooth muscle. OxPCs represent a potential novel target for treating oxidative stress-associated pathobiology in asthma.

Newly divided eosinophils limit ozone-induced airway hyperreactivity in nonsensitized guinea pigs

Ozone causes vagally mediated airway hyperreactivity and recruits inflammatory cells, including eosinophils, to lungs, where they mediate ozone-induced hyperreactivity 1 day after exposure but are paradoxically protective 3 days later. We aimed to test the role of newly divided eosinophils in ozone-induced airway hyperreactivity in sensitized and nonsensitized guinea pigs. Nonsensitized and sensitized guinea pigs were treated with 5-bromo-2-deoxyuridine (BrdU) to label newly divided cells and were exposed to air or ozone for 4 h. Later (1 or 3 days later), vagally induced bronchoconstriction was measured, and inflammatory cells were harvested from bone marrow, blood, and bronchoalveolar lavage. Ozone induced eosinophil hematopoiesis. One day after ozone, mature eosinophils dominate the inflammatory response and potentiate vagally induced bronchoconstriction. However, by 3 days, newly divided eosinophils have reached the lungs, where they inhibit ozone-induced airway hyperreactivity because depleting them with antibody to IL-5 or a TNF-α antagonist worsened vagally induced bronchoconstriction. In sensitized guinea pigs, both ozone-induced eosinophil hematopoiesis and subsequent recruitment of newly divided eosinophils to lungs 3 days later failed to occur. Thus mature eosinophils dominated the ozone-induced inflammatory response in sensitized guinea pigs. Depleting these mature eosinophils prevented ozone-induced airway hyperreactivity in sensitized animals. Ozone induces eosinophil hematopoiesis and recruitment to lungs, where 3 days later, newly divided eosinophils attenuate vagally mediated hyperreactivity. Ozone-induced hematopoiesis of beneficial eosinophils is blocked by a TNF-α antagonist or by prior sensitization. In these animals, mature eosinophils are associated with hyperreactivity. Thus interventions targeting eosinophils, although beneficial in atopic individuals, may delay resolution of airway hyperreactivity in nonatopic individuals.

Effects of academic exam stress on nasal leukotriene B4 and vascular endothelial growth factor in asthma and health

OBJECTIVE

To examine the effect of final exam stress on the concentrations of leukotriene B4 (LTB4) and vascular endothelial growth factor (VEGF) in the upper airways among healthy and asthmatic individuals.

METHOD

Nasal samples were collected from 12 individuals with asthma and 23 healthy controls early and late in a final exam period, and during a low-stress period in the semester. We determined LTB4 and VEGF concentrations using Enzyme-Linked Immunoassays.

RESULTS

Mixed effects analysis of variance models showed that asthmatic participants with allergies in contrast to healthy individuals experienced a decrease in nasal LTB4 during the final exam period as compared to mid-semester (low stress period). There were no significant changes in nasal VEGF across the observation period. Changes in nasal LTB4 and VEGF were not associated with salivary cortisol, exhaled nitric oxide, or spirometric lung function.

CONCLUSIONS

Our results suggest that nasal LTB4 concentrations change in periods of psychological stress for asthmatic individuals with allergies.

Noninvasive effects measurements for air pollution human studies: methods, analysis, and implications

Human exposure studies, compared with cell and animal models, are heavily relied upon to study the associations between health effects in humans and air pollutant inhalation. Human studies vary in exposure methodology, with some work conducted in controlled settings, whereas other studies are conducted in ambient environments. Human studies can also vary in the health metrics explored, as there exists a myriad of health effect end points commonly measured. In this review, we compiled mini reviews of the most commonly used noninvasive health effect end points that are suitable for panel studies of air pollution, broken into cardiovascular end points, respiratory end points, and biomarkers of effect from biological specimens. Pertinent information regarding each health end point and the suggested methods for mobile collection in the field are assessed. In addition, the clinical implications for each health end point are summarized, along with the factors identified that can modify each measurement. Finally, the important research findings regarding each health end point and air pollutant exposures were reviewed. It appeared that most of the adverse health effects end points explored were found to positively correlate with pollutant levels, although differences in study design, pollutants measured, and study population were found to influence the magnitude of these effects. Thus, this review is intended to act as a guide for researchers interested in conducting human exposure studies of air pollutants while in the field, although there can be a wider application for using these end points in many epidemiological study designs.

Analyzing serum eosinophil cationic protein in the clinical assessment of chronic rhinosinusitis

BACKGROUND

Eosinophil cationic protein (ECP) is a major granule-derived protein with cytotoxic activity found in eosinophils and has been known as a useful marker of allergic inflammation. In this study, we assessed the clinical significance of ECP in chronic inflammation of the nasal mucosa by evaluating the relationship between eosinophil activity and serum ECP concentration in a cohort of subjects with or without chronic rhinosinusitis (CRS) and allergic rhinitis (AR).

METHODS

We retrospectively reviewed the medical records of 492 subjects and analyzed eosinophil percentage in nasal smears, serum eosinophil counts, serum ECP concentrations, symptom scores, CT scores, the size of nasal polyp, and recurrence of CRS at follow-up.

RESULTS

Elevated serum ECP concentration was closely related with higher eosinophil expression in all subject's nasal smears and sera. CRS subjects without AR had a higher percentage of immune cells that were eosinophils compared with control subjects and it was similar to subjects' with AR only or with both CRS and AR. CRS subjects without AR also had significantly higher serum ECP concentrations and eosinophil counts compared with control subjects. Additionally, serum ECP concentration was significantly correlated with CT scores, symptom scores, polyp size, and recurrence rate in CRS subjects without AR.

CONCLUSION

Serum ECP concentration can be used as a marker of local and systemic eosinophil expression. We conjecture that although serum ECP elevation may not be specific in AR, analysis of serum ECP concentration could be particularly useful in estimating the progression and prognosis of CRS.

Serum and nasal lavage fluid Clara cell protein decreases in children with allergic rhinitis

BACKGROUND

Allergic rhinitis is among the most common chronic disorders of childhood with prevalence of up to 40% in children. Clara cell secretory protein (CCSP) is secreted by Clara cells in the lining fluid of airways. It has an immune-modulatory and anti-inflammatory activity.

AIM OF WORK

Study aimed at evaluating CCSP as a biomarker in serum and nasal lavage fluid of children with allergic rhinitis.

METHODS

A case-control study was conducted on sera and nasal lavage fluid samples from 15 children with allergic rhinitis and 15 healthy children as a control group.

RESULTS

Children with allergic rhinitis had a male to female ratio 2 to 1, with a mean age of 9.47±2.75 years, while among the healthy group, six were males and nine were females, with a mean age of 8.63±2.28 years. Rhinorrhea and nasal obstruction were the most frequent symptoms (100%) followed by itching (93.3%) then sneezing (73.3%). Among allergic rhinitis patients serum CCSP mean±SD was 2.03±0.59μg/l; it was reliable to predict allergic rhinitis (P<0.0001); while nasal lavage CCSP mean±SD was 12.73±8.25μg/l and it was not reliable to predict allergic rhinitis. Its best cut-off value was 3.75μg/l with a sensitivity of 100%, specificity 80%, with a diagnostic accuracy of 90%.

CONCLUSION

Clara cell secretory protein is a new peripheral sensitive marker of airway injury. Furthermore, serum CCSP level is a predictor of allergic rhinitis but not nasal lavage fluid CCSP.

Indoor insect allergens are potent inducers of experimental eosinophilic esophagitis in mice

EE is an emerging disease reported in children and adults of urbanized countries, where indoor insect allergens are major health risk factors. Review of our hospital patient database uncovered that a number of EE patients have hypersensitivity to indoor cat, dog, cockroach, and dust mite allergens. We tested the hypothesis whether inhaled indoor insect allergens are effective inducers of experimental EE. We delivered cat, dog, cockroach, and dust mite allergen extracts intranasally to wild-type and eotaxin-1/2-, CCR3-, and IL-5-deficient mice. Interestingly, wild-type mice exposed to cockroach or dust mite allergens develop a significant increase in the levels of esophageal eosinophils and mast cells compared with saline-challenged mice. The eosinophil numbers in the esophagus of cockroach- and dust mite-exposed mice were 18.3+/-6.8/mm2 and 33.4+/-11.1/mm2 compared with 2.3+/-1.8/mm2 and 2.1+/-1.2/mm2 in saline-challenged mice. Additionally, we observed an additive effect of these two allergens in inducing esophageal eosinophilia and mastocytosis. Histopathological analysis detected intraepithelial esophageal eosinophilia in mice exposed to both allergens. Furthermore, mice exposed to cockroach and/or dust mite had increased levels of total IgE and antigen-specific IgG1 in the blood and increased esophageal expression of eosinophil-active cytokines (IL-13) and chemokines (eotaxin-1). Notably, mice deficient in eotaxin-1/2, CCR3, and IL-5 showed ablated esophageal eosinophilia following cockroach or dust mite allergen exposure. These data indicate that indoor insect allergens are potent inducers of IL-5 and eotaxin-mediated esophageal eosinophilia. These experimental studies are in accordance with clinical data but may have some limitations inherent to animal models of human disease.

Infections

This chapter reviews the epidemiological evidence implicating infectious pathogens as triggers and will discuss the mechanisms of interaction between the host–pathogen response and preexisting airway pathology that result in an exacerbation. Asthma is a multifaceted syndrome involving atopy, bronchial hyperreactivity, and IgE and non-IgE-mediated acute and chronic immune responses. The asthmatic airway is characterized by an infiltrate of eosinophils and of T-lymphocytes expressing the type 2 cytokines IL-4, IL-5, and IL-13. Trigger factors associated with acute exacerbations of asthma include exposure to environmental allergens, especially animals, molds, pollens and mites, cold, exercise, and drugs. The frequency of exacerbations is a major factor in the quality of life of patients with COPD. The typical clinical features of an exacerbation include increased dyspnea, wheezing, cough, sputum production, and worsened gas exchange. Although noninfectious causes of exacerbations such as allergy, air pollution, or inhaled irritants including cigarette smoke may be important, acute airway infections are the major precipitants. The infection and consequent host inflammatory response result in increased airway obstruction. The success of vaccination to prevent respiratory virus infections has been limited by significant variation within the major virus types causing disease. Currently much of the treatment of infective exacerbations of asthma and COPD is symptomatic, consisting of increased bronchodilators, either short-acting β 2—agonists in inhaled or intravenous form or anticholinergics or theophyllines, or supportive in the form of oxygen and in severe cases noninvasive or invasive ventilatory measures.

Assessment of Upper Respiratory Tract and Ocular Irritative Effects of Volatile Chemicals in Humans

Accurate assessment of upper respiratory tract and ocular irritation is critical for identifying and remedying problems related to overexposure to volatile chemicals, as well as for establishing parameters of irritation useful for regulatory purposes. This article (a) describes the basic anatomy and physiology of the human upper respiratory tract and ocular mucosae, (b) discusses how airborne chemicals induce irritative sensations, and (c) reviews practical means employed for assessing such phenomena, including psychophysical (e.g., threshold and suprathreshold perceptual measures), physiological (e.g., cardiovascular responses), electrophysiological (e.g., event-related potentials), and imaging (e.g., magnetic resonance imaging) techniques. Although traditionally animal models have been used as the first step in assessing such irritation, they are not addressed here since (a) there are numerous reviews available on this topic and (b) many rodents and rabbits are obligate nose breathers whose nasal passages differ considerably from those of humans, potentially limiting generalization of animal-based data to humans. A major goal of this compendium is to inform the reader of procedures for assessing irritation in humans and to provide information of value in the continued interpretation and development of empirical databases upon which future reasoned regulatory health decisions can be made.

Cysteinyl-leukotrienes in nasal lavage fluid in children with asthma

The aim of this study was to investigate repeatability of cysteinyl-leukotrienes (cys-LT) measurements in nasal lavage fluid (NLF) and to determine if cys-LT levels in NLF are related to asthma severity in children. As a second outcome, we investigated if cys-LT in NLF reflect lower airway inflammation as assessed by exhaled NO measurement. To assess the repeatability of cys-LT measurements, two NLF samples were obtained from eight healthy controls 24 h apart. Sixty-nine asthmatic children (mean age; range: 12.8; 7.3-17.7 yr), which were grouped according to asthma severity were studied cross-sectionally on one occasion. Cys-LT in NLF were analyzed using a specific enzyme immunoassay, exhaled NO, and pulmonary function parameters were measured. The coefficient of repeatability for the repeated cys-LT measurements was 1.45 pg/ml. Cys-LT levels in NLF differed significantly between asthma severity groups (p < 0.001): mild intermittent: [median (IQR)] 6.88 pg/ml (2.00-27.87); mild persistent: 21.09 pg/ml (4.50-84.67); and moderate persistent asthmatics: 36.41 pg/ml (11.03-118.40). Concentration of cys-LT in NLF and exhaled NO was positively correlated (r = 0.85; p < 0.001). In conclusion, concentration of cys-LT in NLF correlates with asthma severity in children and is related to lower airway inflammation.

Enhanced severity of virus associated lower respiratory tract disease in asthma patients may not be associated with delayed viral clearance and increased viral load in the upper respiratory tract

BACKGROUND

Viral respiratory infections, particularly human rhinovirus (HRV) infections, are the most common cause of asthma exacerbation. HRV infections usually lead to more severe and longer duration of lower respiratory tract (LRT) symptoms in asthmatics than in otherwise healthy individuals. However, the exact mechanism by which viruses contribute to exacerbation of asthma is unknown.

OBJECTIVES

The main objective of our study was to investigate the relationship of the enhanced severity of LRT symptoms to viral dynamics or cytokine responses in the upper respiratory tract (URT).

STUDY DESIGN

Therefore, we conducted a longitudinal study in which asthmatics and healthy controls were followed during natural viral respiratory tract infections.

RESULTS

Our study confirmed that viral respiratory tract infections caused more severe problems of the LRT in asthma patients as compared to healthy controls. However, for all subjects, the severity of LRT symptoms were not related to viral load or prolonged viral shedding in the URT. In addition, we did not detect differences in proinflammatory cytokines in the URT between asthmatics and controls.

CONCLUSION

Persistence of the virus, as well as viral load in the URT, may not be associated with the induction and/or persistence of asthmatic symptoms.

Circulating neutrophil CD14 expression and the inverse association of ambient particulate matter on lung function in asthmatic children

BACKGROUND

Identifying baseline inflammatory biomarkers that predict susceptibility to size-specific particulate matter (PM) independent of gaseous pollutants could help us better identify asthmatic subpopulations at increased risk for the adverse health effects of PM.

OBJECTIVE

To evaluate whether the association between lung function and exposure to ambient levels of PM less than 2.5 microm in diameter (PM2.5) (fine) and 10 to 2.5 microm in diameter (PM(10-2.5)) (coarse) in children with persistent asthma differed across baseline measures of inflammation and innate immune activation.

METHODS

We performed a panel study on a local population of 16 children with persistent asthma and evaluated daily pulmonary function (percentage of predicted peak expiratory flow and forced expiratory volume in 1 second) while concurrently measuring daily PM2.5 and PM(10-2.5) exposure from a central site in Chapel Hill, North Carolina. The children underwent a baseline medical evaluation that included assessment of several immunoinflammatory biomarkers in peripheral blood.

RESULTS

Children without measurable CD14 expression on circulating neutrophils had significantly reduced pulmonary function (forced expiratory volume in 1 second and peak expiratory flow) with each interquartile range (IQR) increase in PM2.5 (IQR = 8.5 microg/m3) and PM(10-2.5) (IQR = 4.1 microg/m3) concentration, unlike children with measurable CD14 expression (P < .001 for interaction).

CONCLUSIONS

Asthmatic children with muted surface expression of CD14 on circulating neutrophils may have a decreased capacity to respond to bacterial components of PM.

Nasal effects of a mixture of volatile organic compounds and their ozone oxidation products

OBJECTIVE

Our objective was to determine if low levels of a mixture of volatile organic compounds (VOCs) and their ozone (O3) oxidation products, similar to what might be found in "sick buildings," cause nasal irritation and inflammation under controlled exposure conditions.

METHODS

Healthy, nonsmoking women (n=130) completed 2-hour controlled exposures to VOCs, VOCs and O3, and a masked air "MA" control in random order at least 1 week apart. VOCs and O3 concentrations were approximately 25 mg/m and approximately 40 ppb, respectively. Nasal symptoms were rated before, during, and after exposure. Nasal lavage fluid was analyzed for polymorphonuclear cells, total protein, interleukin-6, and interleukin-8.

RESULTS

We found no significant differences in symptoms or markers of nasal inflammation between exposure conditions.

CONCLUSIONS

Results suggest that VOCs and their oxidation products may not cause acute nasal effects at low concentrations.

Repeated measurement of nasal lavage fluid chemokines in school-age children with asthma

BACKGROUND

Inflammatory processes at the mucosal surface may play a role in maintenance of asthma pathophysiology. Cross-sectional studies in asthmatic patients suggest that chemokines such as interleukin 8 (IL-8) are overproduced by respiratory epithelium.

OBJECTIVE

To test the hypothesis that chemokine levels are persistently elevated in the respiratory secretions of asthmatic children at a stable baseline.

METHODS

We measured nasal lavage fluid (NLF) levels of chemokines and other mediators at 3- to 4-month intervals in a longitudinal study of asthmatic children, with nonasthmatic siblings as controls.

RESULTS

In a linear mixed-model analysis, both family and day of visit had significant effects on nasal mediators. Thus, data for 12 asthmatic-nonasthmatic sibling pairs who had 3 or more same-day visits were analyzed separately. For sibling pairs, median eosinophil cationic protein levels derived from serial measurements in NLF were elevated in asthmatic patients compared with nonasthmatic patients, with a near-significant tendency for elevation of total protein and eotaxin levels as well. However, no significant differences were found for IL-8 or several other chemokines. Ratios of IL-13 or IL-5 to interferon-gamma released by house dust mite antigen-stimulated peripheral blood mononuclear cells, tested on a single occasion, were significantly increased for asthmatic patients.

CONCLUSIONS

Substantial temporal and family-related variability exists in nasal inflammation in asthmatic children. Although higher levels of eosinophil cationic protein are usually present in NLF of patients with stable asthma compared with patients without asthma, chemokines other than eotaxin are not consistently increased. Eosinophil activation at the mucosal surface is a more consistent predictor of asthmatic symptoms than nonspecific elevation of epithelium-derived inflammatory chemokine levels.

Nasal wash as an alternative to bronchoalveolar lavage in detecting early pulmonary inflammation in children with cystic fibrosis

OBJECTIVE

The aim of this study was to determine whether nasal inflammation reflects pulmonary inflammation in young children with cystic fibrosis (CF), as assessed by inflammatory markers in nasal wash (NW) and bronchoalveolar lavage (BAL), respectively.

METHODS

CF patients younger than 6 years of age who were to undergo bronchoscopy for routine BAL from May 2000 to October 2001 were recruited for this study. NW was collected immediately after the patient was sedated for bronchoscopy. Total cell counts (TCC), differential cell counts and interleukin (IL)-8 levels (enzyme-linked immunosorbent assay) were assessed in NW and BAL.

RESULTS

In total, 19 children with CF (mean age, 1.9 years; SD, 1.7 years) were included in the study. There was a significant relationship between IL-8 and the percentages of neutrophils in NW (r (2) = 0.76; P < 0.001) and in BAL fluid (r 2 = 0.62; P = 0.006). Similarly, IL-8 concentrations in the NW correlated with those in the BAL (r 2 = 0.48; P = 0.036) and neutrophil percentages in NW correlated significantly with those in BAL (r 2 = 0.7; P = 0.004).

CONCLUSION

When measured under 'ideal' conditions, nasal IL-8 reflects lower airway levels and may reflect the inflammatory stimulus that results in neutrophilic inflammation. These data encourage further assessment of nasal wash under clinically appropriate conditions to determine its utility for assessing inflammation in young children with CF.

Antioxidant supplementation and nasal inflammatory responses among young asthmatics exposed to high levels of ozone

The inflammatory response to ozone in atopic asthma suggests that soluble mediators of inflammation are released in response to oxidant stress. Antioxidants may alleviate additional oxidative stress associated with photochemical oxidant pollution. This study investigates the impact of antioxidant supplementation on the nasal inflammatory response to ozone exposure in atopic asthmatic children. We conducted a randomized trial using a double-blinded design. Children with asthma (n = 117), residents of Mexico City, were given randomly a daily supplement of vitamins (50 mg/day of vitamin E and 250 mg/day of vitamin C) or placebo. Nasal lavages were performed three times during the 4-month follow-up and analysed for content of interleukin-6 (IL-6), IL-8, uric acid and glutathione (GSx). IL-6 levels in the nasal lavage were increased significantly in the placebo group after ozone exposure while no increase was observed in the supplement group. The difference in response to ozone exposure between the two groups was significant (P = 0.02). Results were similar for IL-8, but with no significant difference between the groups (P = 0.12). GSx decreased significantly in both groups. Uric acid decreased slightly in the placebo group. Our data suggest that vitamin C and E supplementation above the minimum dietary requirement in asthmatic children with a low intake of vitamin E might provide some protection against the nasal acute inflammatory response to ozone.

Cell and cytokine profile in nasal secretions in cystic fibrosis

BACKGROUND

Nasal polyposis (NP) frequently complicates the course of cystic fibrosis (CF). The aim of this study was to determine the pattern of inflammatory cells and mediators in nasal secretions from patients with or without NP compared to patients with idiopathic NP and healthy controls.

METHODS

Eighteen CF patients with NP (NP+ group: 6 untreated, 12 treated with nasal steroids), and 15 without NP (NP- group) were included in this prospective study and compared to 9 patients with idiopathic NP and 12 healthy controls. Differential cell count eosinophil cationic protein (ECP), interleukin-5 (IL-5) and IL-8 were determined in nasal lavage fluids.

RESULTS

The total cell count, the number and the percentage of neutrophils and eosinophils, the levels of IL-8, IL-5 and ECP were significantly higher in nasal secretions from both NP+ and NP- as compared with controls. No difference was found between untreated and treated CF patients with NP. No difference was found between NP+ and NP- groups. Compared to idiopathic NP group, both NP+ and NP- groups had higher percentage of neutrophils and lower percentage of eosinophils. There were no differences according to the use of topical steroids, systemic antibiotherapy, or the type of mutation. CF patients with positive nasal culture had a higher percentage of neutrophils than those with negative culture. CF patients with atopy had a higher percentage of eosinophils than non-atopic patients.

CONCLUSION

Our results demonstrate that nasal inflammation is a prominent feature in patients with CF and does not differ according to the presence of NP. IL-8 and IL-5 may play crucial roles in recruitment and activation of neutrophils and eosinophils in upper airways of CF patients.

Inflammatory mediators in nasal lavage among school-age children from urban and rural areas in São Paulo, Brazil

CONTEXT

Some studies have shown that inflammatory processes in the nasal air passages may reflect or affect those in the lower airways. We decided to indirectly assess the inflammatory status of the nasal airways in two groups of children with different sensitization rates to aeroallergens.

OBJECTIVE

To compare the inflammatory activity in the nasal airways, through the determination of mediators in nasal lavage fluid in two distinct populations.

TYPE OF STUDY

Cross-sectional study.

SETTING

Two public elementary schools, one in an urban setting and the other in a rural setting of the State of São Paulo, Brazil.

METHODS

Two groups of 40 elementary school children with different sensitization rates to aeroallergens were formed. Samples of nasal lavage fluid were assessed for eosinophil cationic protein (ECP) and tryptase. Non-parametric tests were used for statistical analysis.

RESULTS

Significantly higher levels of ECP were observed among students living in the urban area than those in the rural area (p < 0.05). No significant difference in the tryptase levels was observed. Also, the urban children who were sensitized to aeroallergens presented higher levels of ECP in nasal mucosa than the non-sensitized children, while this difference was not observed among the rural children.

DISCUSSION

The lack of mast cell activity and increased eosinophil degranulation revealed a chronic inflammatory state in the nasal air passages. The higher eosinophil activity in the urban area, coinciding with higher sensitization to aeroallergens, suggests that there must be some factors in the urban area that can modulate airway inflammation by influencing the activation of inflammatory cells.

CONCLUSION

Our findings showed that there was no difference in the concentrations of tryptase in nasal lavage fluids between the two studied groups. However, the children from the urban area presented with higher concentrations of eosinophil cationic protein than did those from the rural area. Also, the urban children who were sensitized to aeroallergens presented with greater concentrations of eosinophil cationic protein in nasal mucosa than the non-sensitized children, while this difference was not observed among the rural children.

Exhaled NO and eosinophil markers in blood, nasal lavage and sputum in children with asthma after withdrawal of budesonide

BACKGROUND

There is a need for controlled trials among children with asthma to evaluate and compare different markers of inflammation.

OBJECTIVE

Our goal was to investigate the effect of withdrawal of inhaled budesonide on repeated measurements of exhaled NO (ENO), peripheral blood eosinophils (PBE), sputum/NAL/serum-eosinophil cationic protein (ECP), bronchial hyperresponsiveness (BHR) and forced expiratory volume in 1 s (FEV(1)) in children with allergic asthma.

METHODS

Eighteen asthmatic children were randomly allocated to continue or discontinue use of inhaled budesonide. They were followed up, at six visits for 4 months with regular blood, serum, sputum, and NAL samples. Sixteen age-matched healthy children served as controls.

RESULTS

ENO, PBE, and S-ECP increased significantly in the withdrawal group (p < 0.05) but not in the continuous treatment group. No trend could be observed during the study for markers in sputum or in NAL in either group.

CONCLUSION

The present data provide evidence for the clinical usefulness of measuring ENO, PBE, and S-ECP and when combined they could help to avoid over- and undertreatment with corticosteroids in the growing child.

Cytokine secretion in nasal mucus of normal subjects and patients with allergic rhinitis

Allergic rhinitis is regulated by the local production and release of several cytokines. The levels of Th2 cytokines IL-4, IL-6, IL-10 and the Th1 cytokine IFN-gamma were studied in nasal mucus from 30 subjects with allergic rhinitis and 45 non-atopic healthy controls. In this study a sampling technique for collecting nasal mucus, well tolerated by the subjects and with a minimal stimulation of the mucosa, was performed. The cytokine concentrations in nasal mucus samples were detected and quantitated by a new paramagnetic particle-based immunofluorescent assay system more sensitive than the conventional ELISA techniques. The new technique showed reliable values of the measured parameters. The nasal mucus from allergic patients contained significantly higher concentrations of IL-4 (25.5 +/- 3.6 pg/ml; P < 0.001) and IL-10 (1300 +/- 190 pg/ml; P < 0.05) compared to the nasal mucus from control subjects (15.2 +/- 2.3 and 532 +/- 28 pg/ml, respectively, for IL-4 and IL-10). No significant modification in IFN-gamma levels of allergic patients was found when compared to control group (respectively, 19.9 +/- 3.3 vs. 25.7 +/- 5.1 pg/ml; P > 0.05). Moreover, the allergic patients showed lower levels of IL-6 concentrations in the nasal mucus compared to control subjects (64.8 +/- 9.1 vs. 129.0 +/- 18.1 pg/ml; P = 0.0099). These data can be interpreted by the hypothesis that in response to environmental allergens there is a preferential Th2 polarity by activated CD4+ T cells and that the cytokines IL-6 and IL-10 have, respectively, an important anti-inflammatory and counterregulatory action in the pathogenesis of allergic rhinitis.

Host defense function of the airway epithelium in health and disease: clinical background

Respiratory infection is extremely common and a major cause of morbidity and mortality worldwide. The airway epithelium has an important role in host defense against infection and this is illustrated in this review by considering infection by respiratory viruses. In patients with asthma or chronic obstructive pulmonary disease, respiratory viruses are a common trigger of exacerbations. Rhinoviruses (RV) are the most common virus type detected. Knowledge of the immunopathogenesis of such RV-induced exacerbations remains limited, but information is available from in vitro and from in vivo studies, especially of experimental infection in human volunteers. RV infects and replicates within epithelial cells (EC) of the lower respiratory tract. EC are an important component of the innate-immune response to RV infection. The interaction between virus and the intracellular signaling pathways of the host cell results in activation of potentially antiviral mechanisms, including type 1 interferons and nitric oxide, and in the production of cytokines and chemokines [interleukin (IL)-1 beta, IL-6, IL-8, IL-11, IL-16, tumor necrosis factor alpha, granulocyte macrophage-colony stimulating factor, growth-regulated oncogene-alpha, epithelial neutrophil-activating protein-78, regulated on activation, normal T expressed and secreted, eotaxin 1/2, macrophage-inflammatory protein-1 alpha], which influence the subsequent induced innate- and specific-immune response. Although this is beneficial in facilitating clearance of virus from the respiratory tract, the generation of proinflammatory mediators and the recruitment of inflammatory cells result in a degree of immunopathology and may amplify pre-existing airway inflammation. Further research will be necessary to determine whether modification of EC responses to respiratory virus infection will be of therapeutic benefit.

Reduction of chemokine IL-8 and RANTES expression in human bronchial epithelial cells by a sea-water derived saline through inhibited nuclear factor-kappaB activation

The NaCl content of airway surface fluid is believed to be of central importance in lung pathology. To test whether the Na+ concentration could influence the inflammatory response in human bronchial epithelial cells (BECs), we investigated the interleukin (IL)-8 and RANTES expression in BECs exposed to an isotonic sea-water derived low Na+ (ISW) saline compared to isotonic 0.9% NaCl saline. Exposure of BECs to ISW saline caused a significant decrease in IL-8 and RANTES gene expression and protein production as compared to that observed with 0.9% NaCl saline. Furthermore, we observed a concomitant reduction of phosphorylated IkappaBalpha associated with a marked inhibition of NF-kappaB-DNA binding activity in BECs exposed to ISW saline as compared to 0.9% NaCl saline. These findings support a new role for Na+ in the pathogenesis of airway inflammatory disorders. Therapies targeted at lowering Na+ level in airway epithelium may be beneficial in treating inflammatory lung diseases.

An adult model of exclusive viral wheeze: inflammation in the upper and lower respiratory tracts

BACKGROUND

We have previously reported an experimental infection of young adults with a history of episodic and exclusive viral wheeze (EVW) using human coronavirus, in which 16 of 24 with EVW (15 atopic) and 11 of 19 healthy controls (seven atopic) developed a symptomatic cold with evidence of infection, but only those with EVW developed lower respiratory tract symptoms and increased airway responsiveness.

OBJECTIVE

The aim of this study was to compare the EVW and control groups from this study for inflammatory changes occurring in the upper and lower respiratory tracts during the experimental infection, in particular, to determine whether eosinophil-driven inflammation was associated with EVW.

METHODS

Nasal lavage and induced sputum were collected prior to inoculation (day 0) and 2, 4 and 17 days later. Differential cell counts were performed and supernatant was assayed for IL-8, IL-5, IFN-gamma, and eosinophilic cationic protein (ECP).

RESULTS

There was no difference between the two groups in any measurement at baseline. In both groups, during colds the volume of nasal secretion increased as did leucocyte counts in both upper and lower respiratory tracts. A modest increase in nasal neutrophil count was seen in both EVW and control groups with symptomatic colds on day 2 (median (quartile) difference from baseline 5.4 (0.0, 11.0) and 1.8 (-1.1, 2.2)x10(4)/mL of secretions, respectively). The change in nasal neutrophil counts in all subjects correlated with nasal symptom scores. A significant relative increase in sputum differential neutrophil count was seen on day 4 in the EVW group with a cold but not in controls (mean difference (95% confidence interval) 20.4 (9.6, 31.1)% and 3.1 (-8.2, 14.5)%, respectively, P<0.01); however, this increase did not correlate with lower respiratory tract symptom scores. IL-8 increased in both the upper and lower respiratory tracts in both EVW and control subjects with colds, the largest change being seen on day 4 in the sputum of those with EVW (mean difference from baseline (95% confidence interval) 2.5 (0.55-4.46) ng/mL). Only modest changes were seen in IFN-gamma and no changes were seen in IL-5 or ECP. None of the results was influenced by the atopic status of the subjects in either group.

CONCLUSIONS

EVW wheeze is characterized by neutrophilic inflammation in both the upper and lower respiratory tracts without eosinophilia (even in atopic subjects). IL-8 is likely to be an important chemokine in this process. Symptoms and airway responsiveness were correlated with change in neutrophils.

Modulation of lipopolysaccharide-induced proinflammatory cytokine production by satratoxins and other macrocyclic trichothecenes in the murine macrophage

The satratoxins and other macrocyclic trichothecene mycotoxins are produced by Stachybotrys, a mold that is often found in water-damaged dwellings and office buildings. To test the potential immunomodulatory effects of these mycotoxins, RAW 264.7 murine macrophage cells were treated with various concentrations of satratoxin G (SG), isosatratoxin F (iSF), satratoxin H (SH), roridin A (RA), and verrucarin A (VA) for 48 h in the presence or absence of suboptimal concentra-tion of lipopolysaccharide (LPS, 50 ng/ml), and tumor necrosis factor-alpha (TNF-alpha ) and interleukin-6 (IL-6) production were assayed by enzyme-linked immunosorbent assay (ELISA). In LPS-stimulated cultures, TNF-alpha supernatant concentrations were significantly increased in the presence of 2.5, 2.5, and 1 ng/ml of SG, SH, and RA, respectively, whereas IL-6 concentrations were not affected by the same concentrations these macrocyclic trichothecenes. When cells that were treated with LPS and SG (2.5 ng/ml) were evaluated by real-time polymerase chain reaction (PCR),TNF-alpha mRNA was found to increase at 24, 36, and 48 h compared to control cells. At higher concentrations, cytokine production and cell viability were markedly impaired in LPS-stimulated cells. Without LPS stimulation, neither TNF-alpha, nor IL-6 was induced. These results indicate that low concentrations of macrocyclic trichothecenes superinduce expression of TNF-alpha, whereas higher concentrations of these toxins are cytotoxic and concurrently reduce cytokine production. The capacity of satratoxins and other macrocyclic trichothecenes to alter cytokine production may play an etiologic role in outbreaks of Stachybotrys-associated human illnesses.

Infections

Infection, in particular by respiratory viruses, plays an important role in triggering exacerbations and has also been implicated in the etiology of asthma and chronic obstructive pulmonary disease (COPD). This chapter reviews the epidemiological evidence that implicates infectious pathogens as triggers. The chapter also discusses the mechanisms of interaction between the host-pathogen response and preexisting airway pathology resulting in an exacerbation. Much of the treatment of infective exacerbations for both asthma and COPD is symptomatic, consisting of bronchodilators or supportive in the form of oxygen, and in severe cases it includes noninvasive or invasive ventilatory measures. The current therapy for virus-induced exacerbations of asthma and COPD relies on increased treatment of preexisting disease. Antibiotics are indicated for bacterial infections. The effective use of antiviral agents, particularly for influenza viruses, requires viral diagnosis, commencement of treatment early in the course of an exacerbation, or the targeting of high-risk groups for prophylaxis. Alternative strategies for drug development involve the identification of key factors common to exacerbations induced by a range of different viruses. Increased knowledge of the host–virus interaction can help in designing treatments that can increase virus clearance and minimize immunopathology.

Eosinophil cationic protein and specific IgE in serum and nasal mucosa of patients with grass-pollen-allergic rhinitis and asthma

BACKGROUND

After allergen exposure, IgE-bearing mast cells surface in respiratory mucosa. Eosinophils are also recruited locally by chemotactic mediators; they are the main cell directly involved in the late phase of allergic inflammation. IgE antibody and eosinophil cationic protein (ECP) are routinely determined mainly in serum although they exert their pathogenetic role more directly on mucosal surfaces.

METHODS

We performed a comparative study of IgE antibody to grass and ECP on nasal mucosa and blood samples in order to evaluate the relevance of monitoring allergic inflammation in the target organ. Thirty-one patients and 10 nonatopic controls were enrolled in the protocol. Twenty-six subjects allergic to grass, 11 with rhinitis (group 1) and 15 with asthma and rhinitis (group 2), completed the study. Five patients dropped out. Specific IgE to grass and ECP was determined in nasal mucosa by our method based on in situ incubation.

RESULTS

Serum IgE to grass did not increase during the pollen peak, as did nasal IgE, in group 1 from before the pollen peak, from 2.3 to 3.2 kU/l (P=0.02), and in group 2 at the pollen peak, from 4.8 to 12.2 kU/l (P=0.01). Serum ECP did not show any significant variation in group 1, but it increased at pollen peak from 6 to 11.2 microg/l (P=0.01) in group 2. Nasal ECP increased significantly in both groups even before the pollen peak. In group 1, ECP values rose from 15 to 39.9 microg/l (P=0.01). In group 2, ECP increase was much higher than in group 1, from 9 to 213 microg/l (P=0.001). Serum eosinophils, like nasal ECP, showed a significant increase of values from before the pollen peak in both groups, without correlation with serum ECP in rhinitic patients.

CONCLUSIONS

Both specific IgE and ECP in the nasal mucosa showed a better correlation with allergen exposure than serum evaluations. With an appropriate method, allergic inflammation may be best monitored in the nasal mucosa.

Interaction of cigarette smoke and house dust mite allergens on inflammatory mediator release from primary cultures of human bronchial epithelial cells

Several studies have shown that exposure to cigarette smoke and/or house dust mite (HDM) can lead to increased airway inflammation in susceptible individuals. The underlying mechanisms, however, are not defined. To investigate the interaction between cigarette smoke and HDM allergen on mediator release from primary cultures of human bronchial epithelial cells. Confluent human bronchial epithelial cell cultures were exposed to cigarette smoke in the absence or presence of HDM allergen and investigated for the release of IL-8, IL-1beta, and sICAM-1. Damage to the epithelial cells themselves was assessed by release of 51Cr. On separate occasions, we investigated the effect of PTL11028, a highly potent and selective Der p1 inhibitor, on HDM allergen-induced release of IL-8, following activation of HDM allergen by incubation with cysteine. The effect of cigarette smoke exposure on the stability of these released mediators in prepared solutions in the absence/presence of reduced glutathione was also studied. Both HDM allergens and short-term (20 min) cigarette smoke exposure led to a significantly increased release of IL-8, IL-1beta and sICAM-1 from the epithelial cell cultures. Longer exposure (1-6 h) to cigarette smoke led to a dramatic decrease in the amount of these mediators detected in the culture medium. Whilst incubation of epithelial cultures with HDM allergen did not cause any significant change in the release of 51Cr from pre-loaded cells, cigarette smoke on its own led to a marked, exposure and incubation-time dependent increase in the release of 51Cr. Incubation with HDM allergen led to a significant, dose and time-dependent increase in the release of IL-8, which was further enhanced when the allergen extract was pre-activated with cysteine. This effect was completely abrogated by PTL11028, a novel Der p1 inhibitor. Prepared solutions of various concentrations of IL-8, IL-1beta and sICAM-1 exposed to cigarette smoke demonstrated a dramatic exposure time-dependent decrease in the detectable amount of these mediators, an effect which was abrogated by GSH. HDM-induced airway inflammation may include Der p-mediated release of inflammatory mediators from epithelial cells. Additionally, short-term cigarette smoke exposure may induce airway inflammation by release of inflammatory mediators from these cells, an effect which may be potentiated by Der p allergens. Longer term cigarette smoke exposure may cause damage to epithelial cells and changes in the structure of inflammatory mediators.

Eosinophil cationic protein and eosinophil protein X in the nasal lavage of children during the first 4 weeks of life. SPACE Collaborative Study Team

Eosinophil cationic protein (ECP) and eosinophil protein X (EPX) are well established as markers of eosinophil activation. We analyzed ECP and EPX concentrations in nasal lavage fluids (NALF) of 378 neonates during their first 4 weeks of life. Inclusion criteria were a positive history of parental allergy and a positive skin prick test or specific IgE (RAST class > or = 2) against at least one out of a panel of common aeroallergens in one or both parents. Twenty-four infants with no history of parental allergy were used as controls. A volume of 2 ml of 0.9% saline was instilled into each nostril and immediately recovered by a suction device. ECP and EPX were analyzed by radioimmunoassay. In 65 samples of three consecutive lavages, EPX was detected in nine samples (13.8%) in the control group, whereas it was detected in 197/360 samples (54.7%) in the study population. The corresponding figures for ECP were 17/65 (26.2%) in the control group and 173/365 (47.4%) in the study group. Both proteins showed a skewed distribution (median/5-95th percentiles for ECP: 0 microg/l [0-69.4] and EPX: 6.6 microg/l [0-73.2]). The differences between the control group and the study group were statistically significant, regardless of the allergic disease of the parents. In children of allergic parents, activation proteins of the eosinophil granulocyte are released on the nasal mucosal surface in about 50% of the studied population at the age of 4 weeks. This early onset of eosinophil activation in the nasal respiratory epithelium may reflect a genetic predisposition to allergy or early exposure to allergens.

Analysis of local cytokine gene expression in patients with allergic rhinitis treated with CO2 laser surgery

OBJECTIVES/HYPOTHESIS

Laser surgery of the inferior turbinates has become a popular surgical treatment for patients with allergic rhinitis, particularly for those who have persistent nasal obstruction and do not respond well to pharmacological therapy. The aim of this study was to investigate the effects of the laser surgery on local cytokine gene expression at the mucosal surface in relation to the improvement of nasal symptoms.

STUDY DESIGN

A prospective analysis of 25 patients with allergic rhinitis caused by the house dust mite who underwent laser surgery twice with a 1-month interval on an outpatient basis. Fifteen healthy volunteers served as normal control subjects.

METHODS

Improvement of the nasal symptoms was evaluated on a graded scale. Nasal mucosal cells were obtained by brushing from the inferior turbinate at each visit. The expression of messenger RNA (mRNA) encoding granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-6, IL-8, RANTES (regulated on activation, normal T-cell expressed and secreted), and eotaxin was semiquantitatively analyzed by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Two months after treatment, the nasal symptom scores significantly decreased from baseline. The decrease was most apparent in nasal obstruction. RT-PCR analysis revealed that a significant decrease in IL-8 and RANTES expression (P < .001 and P = .012, respectively) was observed after successive laser treatment, and the reduction in these cytokines was significantly correlated. On the other hand, mRNA expression of GM-CSF, IL-6, and eotaxin remained unchanged.

CONCLUSIONS

This study provided evidence that the expression of local inflammatory cytokines can be attenuated in part by CO2 laser treatment, which may be closely related to the clinical effectiveness of this procedure.

Chemokines in nasal secretions of normal adults experimentally infected with respiratory syncytial virus

The goal of this study was to determine time courses of upregulation of several chemokines in nasal secretions after inoculation of human subjects with a low dose of live respiratory syncytial virus (RSV). Healthy, nonsmoking young adults were admitted to an inpatient clinical research unit. After baseline studies, subjects were nasally inoculated with approximately 10(3) plaque-forming units of RSV (strain A2), followed by daily nasal lavages. Nasal lavage fluid (NLF) was assayed for chemokines by specific ELISA. Of 10 subjects inoculated with RSV, 3 developed clinical symptoms of upper respiratory infection and also shed virus. Among infected subjects, there was a transient postinoculation increase in interleukin-8 (IL-8) in NLF to an average of 2.7-fold compared to baseline, followed by a prolonged increase (maximum mean 5.4-fold) during virus shedding. RANTES, MIP-1alpha, and MCP-1 all increased during virus shedding only (maximum mean increases of 5.3-fold, 13-fold, and 7.2-fold, respectively). Semiquantitative RT-PCR in brushed nasal epithelial cells on day 6 after inoculation suggested upregulation of RANTES, but not IL-8, mRNA during virus shedding. We conclude that chemokines IL-8, RANTES, MIP-1alpha, and MCP-1 are all increased in nasal secretions in human RSV infection at the time of virus shedding and symptomatic illness and that the epithelium lining the nasal turbinate contributes to the increase in RANTES.

Chemoattractant factors in breast milk from allergic and nonallergic mothers

The allergy-preventing effect of breast-feeding remains controversial, possibly because of individual variations in the composition of the breast milk. Recently, we showed that allergic mothers had higher concentrations of IL-4 and lower concentrations of ovalbumin-specific IgA in their breast milk than nonallergic mothers. The aim of this study was to investigate the concentrations of chemokines and cytokines that are chemotactic to cells involved in allergic reactions in breast milk from allergic and nonallergic mothers. Cytokine and chemokine concentrations were determined with ELISA in colostrum and mature milk samples from 23 mothers with and 25 mothers without atopic symptoms. IL-8 was detected in all milk samples. RANTES (regulated on activation, normal T cell expressed and secreted), eotaxin, and IL-16 were detected in 50%, 76%, and 48%, respectively, in colostrum and less commonly in mature milk. Macrophage inflammatory protein-1alpha, however, could not be detected in any of the samples. The concentrations of IL-8 and RANTES were higher in breast milk from allergic, compared with nonallergic, mothers. In conclusion, the presence of chemoattractant factors in breast milk may be responsible for the traffic of leukocytes from the maternal circulation to the breast milk. The higher concentrations of RANTES and IL-8 in allergic mothers may partly explain the controversy regarding the protective effect of breast-feeding against the development of allergy by stronger chemotaxis and activation of cells involved in allergic diseases, and possibly by elevated IgE production.

Transfection of nasal mucosa with a normal alpha1-antitrypsin gene in alpha1-antitrypsin-deficient subjects: comparison with protein therapy

We sought to determine whether a normal alpha1-antitrypsin (AAT) gene could be expressed in respiratory epithelium and whether local expression would have antiinflammatory effects. In an unblinded study, we delivered a normal AAT gene in a plasmid-cationic liposome complex to one nostril of each of five subjects with AAT deficiency; the other, untreated nostril served as a control. AAT protein concentration in nasal lavage fluid (NALF) increased in the transfected nostril (TN), but not in the control nostril (CN), of every subject, peaking on day 5 at levels about one-third normal (baseline CN, 4.1 +/- 1.2 microg/mg of protein; baseline TN, 4.3 +/- 1.3; day 5 CN, 4.0 +/- 0.5 [p = NS versus baseline]; day 5 TN, 9.0 +/- 1.7 [p < 0.5 versus baseline]); isoelectric focusing identified the transgene-generated protein (M) in the only two patients in whom the measurement was possible. The reverse transcriptase-polymerase chain reaction (RT-PCR), performed on NALF from TN and CN of four of the five subjects, was positive for transgene message in TN in all cases and negative in NALF from CN except for one time point in one subject. Interleukin 8 (IL-8) concentrations in NALF were elevated at baseline (normal [N = 10] = 2.5 +/- 0.5 ng/mg of protein; baseline TN = 5.5 +/- 0.8, p < 0.05 versus normal) and decreased after AAT transfection (TN = 2.9 +/- 0.6, p < 0.05 versus baseline) but not in the control nostril (CN = 6.5 +/- 2.2, p = NS versus baseline). NALF samples taken from four of the patients while receiving intravenous AAT protein showed normal concentrations of AAT, but IL-8 concentrations (10.5 +/- 4.2 ng/mg of protein, p = NS versus baseline) were not decreased from baseline. We conclude that plasmid-cationic liposome delivery of a normal AAT gene to the respiratory epithelium of deficient patients produces potentially therapeutic local AAT concentrations and that AAT gene therapy, unlike AAT protein therapy, is antiinflammatory.

Nasal lavage mediator profile and cellular composition of nasal brushing material during latex challenge tests

BACKGROUND

Recent studies have shown that airborne latex allergens cause allergic rhinitis and bronchial asthma.

OBJECTIVE

The aim of this study was to investigate the association between the development of rhinitis reactions during workplace-related inhalative challenge tests and nasal allergic inflammation.

METHODS

Thirty-two health care workers (HCWs) with suspected respiratory hypersensitivity to latex allergens underwent an inhalative workplace-related challenge test with powdered latex gloves. Nasal lavage fluid (NALF) and nasal brushing (NAB) material were collected before and after exposure (30 min, 2, 6 and 24 h) to determine mediator and cellular composition. In addition, lung function parameters and nasal flow were recorded. Furthermore, six healthy controls underwent nasal brushing and nasal lavage without latex allergen challenge at the same time intervals.

RESULTS

Twenty-six HCWs showed acute rhinitis by contact to airborne latex allergen exposure and 10 of them had an additional asthma response. Only in responders, significantly increased eosinophil levels were found 6 h (P < 0.00001) and 24 h (P < 0.0005) post-challenge when compared with the prechallenge values. The ECP levels measured 2, 6 and 24 h post-challenge in the responder group were significantly elevated when compared with the prechallenge values as well as with the non-responders (6 h: P < 0.05, 24 h: P < 0.00001 afterwards). Only in some concentrated NALF samples of responders collected 30 min post-challenge (seven out of 15) tryptase concentration above the detection limit were found. The NO derivative concentrations in NALF were significantly increased 6 h post-challenge compared with the prechallenge values (P < 0.05) and were significantly higher in responders than in non-responders and in controls (P < 0.002). IL-5 levels increased post-challenge in the responder group with a pronounced effect 6 h after challenge (P < 0.001). Overall, a variety of parameters was significantly correlated (e.g. ECP with NO derivatives, r = 0.792 P < 0.002).

CONCLUSIONS

Our data demonstrate for the first time that nasal and bronchial hyperreactivity to airborne latex allergens are associated with an increase of eosinophils and mediators (e.g. ECP, NO derivatives, IL-5, tryptase) in nasal mucosa. The combined use of NAB (for cells) and NALF (for mediators) appears to be a useful model to monitor nasal inflammation during workplace-related challenge tests.

Lack of relationship between eosinophil cationic protein and eosinophil protein X in nasal lavage and urine and the severity of childhood asthma in a 6-month follow-up study

BACKGROUND

Recent studies suggest that eosinophil cationic protein (ECP) and eosinophil protein X (EPX) may be valuable markers of airway inflammation in various body fluids of asthmatic children. Most of these studies have relied on a single measure of inflammatory markers.

OBJECTIVE

We measured ECP and EPX in nasal lavage fluids (NALF) and urine samples in children with asthma over a 6-month period to study the relationship between inflammatory markers and clinical severity.

METHODS

Fourteen children with mild persisting asthma (mean age 11.7 years, SD 2.2) were recruited. All patients were on therapy including inhaled steroids. For a 6-month period asthma severity was monitored by at least monthly physical examination and pulmonary function tests. Daily morning and evening PEF, asthma symptoms and medication were recorded in diaries for the whole study period. Telephone interviews were performed between visits and additional visits were done in case of an increase in asthmatic symptoms or drop of PEF values under 80% of best value. An exacerbation was defined by a fall of FEV1 > 10% and an increase in asthma symptoms and additional need of beta2-agonist. NALF and urine samples were obtained at each visit and analysed for ECP (NALF only) and EPX.

RESULTS

Mean observation time was 186.4 days (SD 19.8). Thirteen patients completed the study. During the study period 11 exacerbations were observed in six patients. No significant associations between PEF, PEF variability (amplitude % of mean), daily symptoms, additional beta2-agonist, FEV1 and MEF50 and nasal ECP, nasal EPX and urinary EPX were found. However, at exacerbations an average increase of nasal ECP (9.3 vs 50.3 microg/L) and EPX (nasal EPX 36.4 vs 141.7 microg/L, urinary EPX 46.4 vs 74.1 microg/mmol creatinine) was observed.

CONCLUSION

Serial measurements of ECP and EPX in NALF and urine samples do not provide additional information for the practical management in monitoring childhood asthma.

Increase in IL-8, IL-10, IL-13, and RANTES mRNA levels (in situ hybridization) in the nasal mucosa after nasal allergen provocation

BACKGROUND

Allergic inflammation is regulated by the local production and release of several cytokines.

OBJECTIVES

This study was designed to assess the changes in mRNA cytokine-positive cells after allergen provocation and to compare these cytokines with tissue eosinophilia as a marker of allergic inflammation.

METHODS

A grass pollen allergen provocation study was conducted in autumn, out of the hay fever season. Nasal mucosal biopsy specimens were taken before provocation and 1 hour, 24 hours, and 1 week after allergen provocation. Eosinophils and mRNA-positive cells (in situ hybridization for IL-2, IL-3, IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, IFN-gamma, RANTES, and TNF-alpha) were assessed in the biopsy specimens.

RESULTS

After allergen provocation, an increase in cell number was found for eosinophils and cells expressing mRNA for the chemokines IL-8 and RANTES and for the TH2 cytokines IL-10 and IL-13. Significant correlations were found between eosinophils and RANTES and eosinophils and IFN-gamma in the early phase and between eosinophils and IL-5 and eosinophils and RANTES in the late phase. The increase in eosinophils and IL-10 and IL-13 mRNA-positive cells could still be observed 1 week after allergen provocation.

CONCLUSIONS

Nasal allergen provocation induced significant tissue eosinophilia and a significant increase in IL-8, IL-13, and RANTES mRNA-positive cells. A significant increase in eosinophils and IL-10 and IL-13 mRNA-positive cells compared with baseline can still be observed 1 week after a single allergen provocation.

Cytotoxicity, production of reactive oxygen species and cytokines induced by different strains of Stachybotrys sp. from moldy buildings in RAW264.7 macrophages

The ability of different strains of the fungus Stachybotrys, isolated from mold problem buildings, to induce cytotoxicity and production of important inflammatory mediators, i.e. nitric oxide (NO), reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in RAW264.7 macrophages were studied. Several strains of Stachybotrys sp. stimulated immediate increase in the ROS production and in 24-h exposure caused TNF-α and IL-6 release from these cells. However, none of the strains of Stachybotrys sp. was able to induce the expression of inducible nitric oxide synthase (iNOS) and subsequent production of NO in RAW264.7 cells. Moreover, there were significant differences in their ability to induce cytotoxicity in the macrophages. These results suggest that, in addition to direct cytotoxic effects of most Stachybotrys sp., some strains of Stachybotrys sp. stimulate production of inflammatory mediators, TNF-α and IL-6 which were associated with low cytotoxicity in RAW264.7 macrophages.

Low Grade Rhinovirus Infection Induces a Prolonged Release of IL-8 in Pulmonary Epithelium

Rhinoviruses are important respiratory pathogens implicated in asthma exacerbations. The mechanisms by which rhinoviruses trigger inflammatory responses in the lower airway are poorly understood, in particular their ability to infect the lower airway. Bronchial inflammatory cell (lymphocyte and eosinophil) recruitment has been demonstrated. IL-8 is a potent proinflammatory chemokine that is chemotactic for neutrophils, lymphocytes, eosinophils, and monocytes and may be important in the pathogenesis of virus-induced asthma. Increased levels of IL-8 have been found in nasal samples in natural and experimental rhinovirus infections. In these studies we therefore examine the ability of rhinovirus to infect a transformed lower airway epithelial cell line (A549) and to induce IL-8 protein release and mRNA induction. We observed that rhinovirus type 9 is able to undergo full viral replication in A549 cells, and peak viral titers were found 24 h after inoculation. Rhinovirus infection induced a dose- and time-dependent IL-8 release up to 5 days after infection and an increase in IL-8 mRNA expression that was maximal between 3 and 24 h after infection. UV inactivation of the virus completely inhibited replication, but only reduced IL-8 protein production and mRNA induction by half, while prevention of virus-receptor binding completely inhibited virus-induced IL-8 release, suggesting that part of the observed effects was due to viral replication and part was due to virus-receptor binding. These studies demonstrate that rhinoviruses are capable of infecting a pulmonary epithelial cell line and inducing IL-8 release. These findings may be important in understanding the pathogenesis of rhinovirus-induced asthma exacerbations.

Determinants of eosinophil cationic protein in nasal lavages in children

BACKGROUND

Nasal lavages are increasingly used to assess airways inflammation in children. However, there are no studies assessing how measurement error as well as biological influences contribute to the concentration of nasal inflammatory parameters in a population based survey.

OBJECTIVE

To investigate determinants of concentration of eosinophil cationic protein (ECP) in nasal lavages we studied 147 schoolchildren (mean age 8.1 years, SD 0.6 years) by repeated nasal lavages/year over a 2 year period.

METHODS

Standardized questionnaires were completed by the parents each year. A skin-prick test with seven aeroallergens (birch, cat, dog, hazel, weeds, Dermatophagoides pteronyssinus and D. farinae) was performed. One hundred and one children could perform valid lavages at least five times a year. As a measure of reproducibility the intraclass coefficient of reliability was calculated.

RESULTS

The intraclass coefficient of reliability was 0.27 over all observations suggesting that about a quarter of total variance is due to between-subject variance. Taking means over each year increased reliability to 0.60. Linear regression analyses with ECP being the dependent variable demonstrated significant higher values for boys (beta=12.26; P < 0.01), children sensitized to seasonal (beta=34.27; P=0.02) but not to perennial allergens (beta=-4.44; P=0.57), and for children with a serous (beta=10.01; P=0.01) or purulent rhinitis (beta=22.45; P < 0.001).

CONCLUSION

Assessment of inflammatory mediators in nasal lavages is a useful tool for epidemiological paediatric studies. However, due to the relatively high intraindividual variability of ECP concentrations multiple lavages are necessary to characterize the individual.

Effect of thromboxane A2 antagonists on bronchial hyperresponsiveness induced immediately after interleukin-8 inhalation in guinea-pigs

1. Although repeated intranasal administration of interleukin-8 (IL-8) causes bronchial hyperresponsiveness (BHR) mediated via thromboxane A2 (TXA2) and airway neutrophil accumulation in guinea-pigs, the acute effect of inhaled IL-8 is unclear. We performed this study to clarify the acute effect of IL-8 on bronchial responsiveness and the role of TXA2. 2. The effects of inhaled IL-8 on bronchial responsiveness and of the TXA2 antagonists, S-1452 (0.01 and 0.1 mg kg-1) and ONO-NT-126 (1.0 or 10 micrograms kg-1), on IL-8-induced BHR were examined by use of a modified Konzett-Rössler method in guinea-pigs. 3. Inhaled IL-8 at 100 ng ml-1, which failed to induce significant changes in Pao (pressure at the airway opening), enhanced an increase in Pao induced by subsequent inhalations of ascending doses (50-200 micrograms ml-1) of methacholine and histamine, suggesting the potentiating effect of IL-8 on bronchial responsiveness. No significant leukocyte infiltration was observed histologically sixteen minutes after the IL-8 inhalation. Both S-1452 and ONO-NT-126 reduced the IL-8-induced BHR. 4. In conclusion, IL-8 rapidly causes BHR via TXA2 release in guinea-pigs.

Inhibition of airway inflammation in rDer f 2-sensitized mice by oral administration of recombinant der f 2

Recombinant Der f 2 (rDer f 2) is a promising new allergen expected to improve the diagnosis and immunotherapy of house dust mite allergy and to further immunological studies. To evaluate the hyposensitizing activity of rDer f 2 to mite allergy, we examined the effect of its oral administration on allergic inflammation in A/J mice immunized with mite allergens. A/J mice immunized with rDer f 2 alone or rDer f 2 + crude mite extract were orally given 0 (control), 0.01, 0.1, or 1 mg/day of rDer f 2 for 4 weeks, followed by an antigen inhalation challenge. Twenty-four hours after rDer f 2 inhalation, control animals experienced severe leukocyte influx into the airway. The infiltrating cells were mainly neutrophils, with some eosinophils and lymphocytes. The concentrations of IL4, IFNgamma, and soluble ICAM-1 in the bronchial alveolar lavage fluid increased twofold compared with values before rDer f 2 inhalation. In contrast, inflammation was significantly suppressed in mice given 1 mg/day of rDer f 2 orally for 4 weeks and partially suppressed in those fed 0.1 mg/day of the antigen. Plasma anti-rDer f 2 antibody levels were unchanged by oral rDer f 2 treatment. Mite extract inhalation challenge provoked neutophilia in rDer f 2 + mite-sensitized control mice, and this allergic reaction tended to decrease in sensitized mice fed 1 mg/day of rDer f 2 orally for 4 weeks. We conclude that rDer f 2 has hyposensitizing activities and may be useful in immunotherapy for house dust mite allergy.

Rhinovirus stimulation of interleukin-8 in vivo and in vitro: role of NF-kappaB

Neutrophil infiltration is a well-documented early event in the pathogenesis of rhinovirus (RV) infections. To further understand the mechanisms responsible for this neutrophilia, we determined whether interleukin (IL)-8 was present at sites of experimental RV infection in vivo and characterized the mechanism(s) by which RV stimulates IL-8 production in vitro. IL-8 was readily detectable in the nasal washings of all normal volunteers and did not increase with sham nasal inoculation. In contrast, RV infection caused a significant additional increase in nasal IL-8, the levels of which peaked 48-72 h after virus inoculation. RV was a potent stimulator of IL-8 protein production by A549 epithelial-like cells, MRC-5 fibroblasts, and normal human bronchial epithelial cells in vitro. This induction was associated with a significant increase in IL-8 mRNA accumulation and gene transcription. RV also stimulated IL-8 promoter-driven luciferase activity. This stimulation was significantly decreased by mutation of the nuclear factor (NF)-IL-6 site and was completely abrogated by mutation of the NF-kappaB site in this promoter. In addition, NF-kappaB-DNA binding activity was rapidly induced in RV-infected cells. This inducible binding was made up of p65 and, to a lesser extent, p50 NF-kappaB moieties. These studies demonstrate that IL-8 is present in normal nasal secretions and that the levels of IL-8 are further increased after RV infection. They also demonstrate that RVs are potent stimulators of IL-8 production and that this induction is mediated, at least in part, by an NF-kappaB-dependent transcriptional activation pathway. IL-8 may contribute to the pathogenesis of RV infection, and NF-kappaB activation may be a central event in RV-induced pathologies.