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

Implementation of multiomic mass spectrometry approaches for the evaluation of human health following environmental exposure

Omics analyses collectively refer to the possibility of profiling genetic variants, RNA, epigenetic markers, proteins, lipids, and metabolites. The most common analytical approaches used for detecting molecules present within biofluids related to metabolism are vibrational spectroscopy techniques, represented by infrared, Raman, and nuclear magnetic resonance (NMR) spectroscopies and mass spectrometry (MS). Omics-based assessments utilizing MS are rapidly expanding and being applied to various scientific disciplines and clinical settings. Most of the omics instruments are operated by specialists in dedicated laboratories; however, the development of miniature portable omics has made the technology more available to users for field applications. Variations in molecular information gained from omics approaches are useful for evaluating human health following environmental exposure and the development and progression of numerous diseases. As MS technology develops so do statistical and machine learning methods for the detection of molecular deviations from personalized metabolism, which are correlated to altered health conditions, and they are intended to provide a multi-disciplinary overview for researchers interested in adding multiomic analysis to their current efforts. This includes an introduction to mass spectrometry-based omics technologies, current state-of-the-art capabilities and their respective strengths and limitations for surveying molecular information. Furthermore, we describe how knowledge gained from these assessments can be applied to personalized medicine and diagnostic strategies.

Naphthalene: irritative and inflammatory effects on the airways

Objective

This cross-sectional study determined whether acute sensory irritative or (sub)chronic inflammatory effects of the eyes, nose or respiratory tract are observed in employees who are exposed to naphthalene at the workplace.

Methods

Thirtynine healthy and non-smoking male employees with either moderate (n = 22) or high (n = 17) exposure to naphthalene were compared to 22 male employees from the same plants with no or only rare exposure to naphthalene. (Sub)clinical endpoint measures included nasal endoscopy, smell sensitivity, self-reported work-related complaints and the intensity of naphthalene odor and irritation. In addition, cellular and soluble mediators in blood, nasal lavage fluid (NALF) and induced sputum (IS) were analysed. All measurements were carried out pre-shift on Monday and post-shift on Thursday. Personal air monitoring revealed naphthalene shift concentrations up to 11.6 mg/m³ with short-term peak concentrations up to 145.8 mg/m³ and 1- and 2-naphthol levels (sum) in post-shift urine up to 10.1 mg/L.

Results

Acute sensory irritating effects at the eyes and upper airways were reported to occur when directly handling naphthalene (e.g., sieving pure naphthalene). Generally, naphthalene odor was described as intense and unpleasant. Habituation effects or olfactory fatigue were not observed. Endoscopic examination revealed mild inflammatory effects at the nasal mucosa of exposed employees in terms of reddening and swelling and abnormal mucus production. No consistent pattern of cellular and soluble mediators in blood, NALF or IS was observed which would indicate a chronic or acute inflammatory effect of naphthalene in exposed workers.

Conclusions

The results suggest that exposure to naphthalene induces acute sensory irritative effects in exposed workers. No (sub)chronic inflammatory effects on the nasal epithelium or the respiratory tract could be observed under the study conditions described here.

Burnt sugarcane harvesting is associated with rhinitis symptoms and inflammatory markers

INTRODUCTION

Burnt sugarcane harvesting requires intense physical exertion in an environment of high temperature and exposure to particulate matter.

OBJECTIVE

To evaluate the effects of burnt sugarcane harvesting on rhinitis symptoms and inflammatory markers in sugarcane workers.

METHODS

A total of 32 male sugarcane workers were evaluated with questionnaire for rhinitis symptoms, and for inflammatory markers on peripheral blood and nasal lavage, in the non-harvesting, and 3 and 6 months into the sugarcane harvesting period. Weather data and particulate matter fine concentrations were measured in the same day.

RESULTS

The particulate matter concentrations in sugarcane harvesting were 27 (23-33μg/m3), 112 (96-122μg/m3), and 63 (17-263μg/m3); 24h temperatures were 32.6 (25.4-37.4°C), 32.3 (26.7-36.7°C) and 29.7 (24.1-34.0°C) and relative humidities were 45.4 (35.0-59.7%), 47.9 (39.1-63.0%), and 59.9 (34.7-63.2%) in the non-harvesting period, three and 6 months of the harvesting period. The age was 37.4±10.9 years. The prevalence of rhinitis symptoms was significantly higher at 3 months of the harvesting period (53.4%), compared to non-harvesting period (26.7%; p=0.039) and at 6 months into the harvesting period (20%; p=0.006). Concentrations of interleukin 6 (IL-6) in nasal lavage increased after 3 months of the harvesting period compared to the non-harvesting period (p=0.012). The presence of rhinitis symptoms, after 3 months of the harvesting period, was directly associated with blood eosinophils and inversely associated with neutrophils.

CONCLUSIONS

After 3 months of work in burnt sugarcane harvesting the prevalence of rhinitis symptoms and IL-6 in nasal lavage increased. Furthermore, eosinophil counts were directly associated with the rhinitis symptoms in the period of higher concentration of particulate matter.

Nasal Cytology: A Comparative Study of Two Different Techniques of Processing-Smeared versus Cytocentrifuged Slides

Nasal cytology is a precious tool to study nasal disorders, but in current literature, there is no consensus on the standardization of the processing procedure of the obtained samples. Therefore, we decided to test on specimens obtained by nasal scraping, a common way of nasal specimen sampling, two different processing techniques, smear and cytocentrifugation, and compare them in terms of inflammatory cell content, quality of slides, and validity on clinical assessment. We analyzed 105 patients with suspected sinonasal diseases, and in each patient, we performed nasal cytology with both techniques. Our analysis showed a good correlation between the two techniques for neutrophil and eosinophil percentages, both returned well-preserved cells, and showed higher neutrophil percentage in males and in smokers and higher eosinophil percentage in patients with polyposis, with a good concordance with clinical symptoms, as measured by a specific disease-related questionnaire (Sino-Nasal Outcome Test-22). Technically speaking, smeared slides were easier to prepare, with no need of dedicated equipment, but cell distribution was better in cytocentrifuged slides allowing shorter reading time. In conclusion, both techniques can be considered superimposable and worthy to be used.

Adaptation to Occupational Exposure to Moderate Endotoxin Concentrations: A Study in Sewage Treatment Plants in Germany

Acute or chronic inhalation of endotoxin may lead to changes of lung function and inflammatory markers in the airways. Adaptation to workplace exposure may be possible. In this study, we investigated the possible difference in inflammatory markers assessed in nasal lavage fluid (NALF) in chronical exposure compared to voluntary subjects exposed acutely to endotoxin. We sought to define the variability of inflammatory markers in NALF and the dose-related changes after moderate exposure in naïve subjects. Endotoxin exposure (4-1039 EU/m³) resulted from routine work during one shift in sewage treatment plants. Subjects were matched to pairs (8 workers escorted by 10 students). Inflammatory markers were investigated before, directly after, and 16 h after the shift end. Additional NALF samples were collected in students without any specific exposure after 3 days. In NALF, total cell count, and interleukin (IL)-8 and IL-1β concentrations were significantly higher in workers than in students at all times pointing to workplace-related long-lasting exposure resulting in adaptation. However, concentration of inflammatory markers without specific exposure in students showed a great variability, covering the whole range of values recorded in the workers. The findings of this study make us to recommend a repeated assessment of inflammatory markers in healthy volunteers before the investigation of exposure-related changes and a sample size adequate for statistical analysis.

[The usefulness of nasal provocation tests for respiratory physicians]

Rhinitis and asthma are common diseases that are strongly linked from both the epidemiological and patho-physiological point of view. A precise aetiological diagnosis is required in order to optimize treatment. Nasal provocation tests (NPT) determine precisely the role of the allergen in the initiation of the symptoms of rhinitis particularly when the history does not produce convincing evidence of the clinical relevance of an allergen. It may also have important consequences for the choice of an allergenic immunotherapy. NPT are not standardized but simple methods based on international recommendations provide us with good diagnostic accuracy. In this paper, we will discuss the practical aspects of NPT as well as the clinical or research situations where they may be useful for the respiratory physician.

Epithelial proteome profiling suggests the essential role of interferon-inducible proteins in patients with allergic rhinitis

BACKGROUND

Seasonal allergic rhinitis (SAR) caused by intermittent exposure to seasonal pollen causes itching, nasal congestion, and repeated sneezing, with profound effects on quality of life, work productivity, and school performance. Although both the genotype and environmental factors can contribute to the immunologic basis of allergic reactions, the molecular underpinnings associated with the pathogenesis of allergic rhinitis are not entirely clear.

METHODS

To address these questions, nasal epithelial brushings were collected from 29 patients with SAR and 31 control subjects during and after the pollen season. We then implemented an orbitrap-based, bottom-up, label-free quantitative proteomics approach, followed by multivariate analyses to identify differentially abundant (DA) proteins among the 4 sample groups.

RESULTS

We identified a total of 133 DA proteins for which the most significantly overrepresented functional category was found to be interferon 1 signaling. Two proteins, cystatin 1 and myeloblastin, the former of which protects against protease activity of allergens and the latter with a role in epithelial barrier function, were DA in patients with SAR and control subjects, irrespective of season. Moreover, interferon-inducible protein with tetratricopeptide repeats 1, cystatin 1, and interferon-inducible protein with tetratricopeptide repeats 3 were found to be differentially regulated between patients with SAR and control subjects, with inverse abundance dynamics during the transition from fall to spring.

CONCLUSION

We identified type 1 interferon-regulated proteins as biomarkers in patients with SAR, potentially playing an important role in its pathogenesis. Moreover, when compared with patients with SAR, healthy subjects exhibit an antagonistic proteomic response across seasons, which might prove to be a therapeutic target for disease prevention.

Effect of intranasal corticosteroid on pre-onset activation of eosinophils and mast cells in experimental Japanese cedar pollinosis

BACKGROUND

Minimal persistent inflammation (MPI) contributes to hyperreactivity in allergic rhinitis. However, little is known regarding whether pre-onset activation of eosinophils and mast cells is present or not in Japanese cedar pollinosis (JCP). Furthermore, a prophylactic effect of intranasal corticosteroids on such MPI in JCP has not been investigated.

METHODS

We designed a double-blinded, randomized, placebo-controlled, crossover trial. Twenty patients with JCP were examined outside the pollen season (UMIN000008410). Nasal provocation with paper discs containing extracts of Japanese cedar pollen was performed once a day for 3 consecutive days. Onset of nasal symptoms was monitored over 15 min after each provocation. The levels of eosinophil cationic protein (ECP) and tryptase in nasal secretions were examined. Fluticasone furoate nasal spray or placebo treatment was started one day before the first provocation.

RESULTS

In the placebo group, 25% of the patients showed onset of nasal symptoms following provocation on the first day. In addition, 75% and 68% of the patients showed symptom onset on the second and third day of provocation, respectively. After the first provocation, the levels of ECP and tryptase in nasal secretions were significantly increased. These increases were seen not only in symptomatic but also in asymptomatic subjects in response to provocation, and the levels were similar between these subjects. Prophylactic treatment with fluticasone significantly suppressed the increase in nasal ECP and tryptase associated with repeated provocations.

CONCLUSIONS

These results suggest that pre-onset activation of eosinophils and mast cells is present in experimental JCP, and that prophylactic treatment with intranasal corticosteroids has the potential to control such activation.

Diesel exposure suppresses natural killer cell function and resolution of eosinophil inflammation: a randomized controlled trial of exposure in allergic rhinitics

Exposure to diesel exhaust (DE) is known to exacerbate allergic inflammation, including virus-induced eosinophil activation in laboratory animals. We have previously shown that in human volunteers with allergic rhinitis a short-term exposure to DE prior to infection with the live attenuated influenza virus (LAIV) increases markers of allergic inflammation in the nasal mucosa. Specifically, levels of eosinophilic cationic protein (ECP) were significantly enhanced in individuals exposed to DE prior to inoculation with LAIV and this effect was maintained for at least seven days. However, this previous study was limited in its scope of nasal immune endpoints and did not explore potential mechanisms mediating the prolonged exacerbation of allergic inflammation caused by exposure to DE prior to inoculation with LAIV. In this follow-up study, the methods were modified to expand experimental endpoints and explore the potential role of NK cells. The data presented here suggest DE prolongs viral-induced eosinophil activation, which was accompanied by decreased markers of NK cell recruitment and activation. Separate in vitro studies showed that exposure to DE particles decreases the ability of NK cells to kill eosinophils. Taken together, these follow-up studies suggest that DE-induced exacerbation of allergic inflammation in the context of viral infections may be mediated by decreased activity of NK cells and their ability to clear eosinophils.

Analysis of inflammatory markers and metals in nasal lavage fluid of welders

Welding fumes may produce adverse health effects in the respiratory tract. To assess the relationship between exposure to welding fumes and inflammation in the upper airways, 190 male welders were examined from the WELDOX study (median age 40 yr, 54.7% smokers, and 32.9% atopics). Inhalable welding fumes were collected in the breathing zone of welders during a single shift. Chromium (Cr), nickel (Ni), manganese (Mn), and iron (Fe) were measured in the welding-fume samples and in postshift nasal lavage fluid (NALF). In addition, the numbers of particles and inflammatory biomarkers, including total and differential cell counts, interleukin (IL)-8, leukotriene (LT) B₄, 8-isoprostane (8-iso-PGF_2α), tissue inhibitor of metalloproteinase-1 (TIMP-1), and immunoreactive matrix metalloproteinase (MMP)-9, were determined. Metal concentrations in NALF correlated with airborne concentrations. No significant association was found between airborne metal concentrations and biomarkers of inflammation in NALF, whereas increasing metal concentrations in NALF resulted in increased concentrations of total protein, IL-8, MMP-9, and TIMP-1. LTB₄ and 8-iso PGF_2α were elevated at higher concentrations of Cr or Ni in NALF. The same was true for Fe, although the effects were less pronounced and of borderline significance. In conclusion, our results showed a significant association between the concentrations of metals and soluble inflammatory markers in the NALF of welders. The noninvasive collection of NALF is applicable in field studies, where it may serve as a suitable matrix to simultaneously assess biomarkers of exposure and effect in the upper respiratory tract in workers who are occupationally exposed to airborne hazardous substances.

Nasal and systemic inflammatory profile after short term smoking cessation

INTRODUCTION

Smoking cessation promotes health benefits and, despite cigarette smoking be an important pro inflammatory stimulus, there are few studies concerning the nasal and systemic inflammation; as well as the mucociliary clearance behavior in smokers after short period of smoking cessation.

AIM

To evaluate the nasal and systemic inflammatory markers and mucociliary clearance behavior after 30 days of cigarette smoking abstinence.

METHODS

Twenty-five smokers were included and divided into two groups: abstinent smokers (n = 14) and current smokers (n = 11). Tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, IL-8 and IL-10 were measured on nasal lavage and blood serum samples by ELISA at baseline and after 30 days. The mucociliary clearance, exhaled carbon monoxide (exCO) and carboxyhemoglobin (HbCO) were also measured at the same moments.

RESULTS

There was a decrease of TNF-α level only in blood serum at 30 days of abstinence compared to current smokers. The mucociliary clearance improved and there was a reduction in exCO and HbCO (p < 0.05 for all) after 30 days of smoking cessation.

CONCLUSION

The short term smoking abstinence decreased systemic inflammation and improved nasal mucociliary clearance, despite not having changed the nasal inflammation.

Implementation of non-invasive methods in the diagnosis of diisocyanate-induced asthma

Diisocyanate-induced asthma is difficult to diagnose since the immunopathological mechanisms and exposure determinants at the workplace are not well defined. The aim of this study was to evaluate the non-invasive methods of nasal lavage fluid (NALF) and induced sputum (IS) to enhance the diagnostic efficiency. Sixty-three diisocyanate-exposed workers with work-related shortness of breath underwent a standardized 4-steps-1-day-whole body exposure test with diisocyanates used at work up to 30 ppb. NALF and IS were collected before, 0.5, and 19 h after the end of exposure. Cellular composition and soluble inflammatory biomarkers were studied in the samples. In addition, ten controls with bronchial hyperresponsiveness, but without prior occupational diisocyanate exposure, were also examined. Twelve out of the 63 subjects (19 %) showed a significant asthmatic reaction (pulmonary responders) after challenge (FEV1 decrease >20 %). NALF samples did not demonstrate significant effects either on cellular composition or on mediator concentrations in the responders, non-responders, or controls at any time point. In contrast, in the IS samples of the pulmonary responders collected 19 h after challenge, the percentage of eosinophils was higher (p = 0.001) compared with baseline before challenge. Eosinophils were also increased 30 min and 19 h after challenge in IS samples of the responders compared with the non-responders or controls. In addition, 19 h after challenge the eosinophilic cationic protein (ECP) concentration was significantly higher in the responders than non-responders (p < 0.04) or controls (p < 0.002). In conclusion, positive asthmatic reactions to diisocyanates are accompanied by an influx of eosinophils into lower airways. Analysis of induced sputum should be implemented in the diagnostic procedure of diisocyanate-related airway diseases.

Correlation between nasal eosinophils and nasal airflows in children with asthma and/or rhinitis monosensitised to house dust mites

BACKGROUND

Allergic rhinitis and asthma due to mite sensitisation are diseases which are frequently associated and characterised by persistent inflammation. In the present study, we aimed to investigate the relationship between nasal airflows and nasal eosinophils in patients with asthma and/or rhinitis due to house dust mite sensitisation.

METHODS

Twenty-four children with both rhinitis and asthma (R+A), 13 children with rhinitis and no asthma (R) and 10 non-allergic healthy children were evaluated prospectively. The patients belonging to the first two groups had moderate-severe grade of nasal obstruction. Total nasal symptom scores, peak nasal inspiratory flows (PNIFs) obtained by anterior rhinomanometry, skin prick tests, nasal eosinophils and FEV1 values were all assessed.

RESULTS

Percentages of nasal eosinophils and PNIFs in patients with R+A and R (r=-0.415, p=0.04) were found to be statistically significant and to have an inverse correlation. Skin prick tests were also significantly correlated with nasal eosinophils and PNIFs (r=0.372, p=0.01 and r=-0.306, p=0.04, respectively). Both PNIFs and nasal eosinophils of patients with R+A were significantly correlated with FEV1 values (r=-0.641, p=0.001 and r=0.548, p=0.007, respectively).

CONCLUSION

In this study, a close relationship was demonstrated between eosinophil infiltration and nasal airflows in children having asthma and/or rhinitis monosensitised to mites. Additionally, the significant association found between FEV1 values and nasal eosinophils or PNIFs supported the close link of upper and lower airways.

The role of nitrosative stress in the pathogenesis of unexplained chronic cough with cough hypersensitivity

BACKGROUND

Unexplained chronic cough is a common condition without specific causes. A hyperreactivity of the cough reflex has been suggested as a mechanism for inducing chronic cough. We hypothesized that nitrosative stress in the upper airway might play a role in cough hypersensitivity by causing neurochemical abnormalities.

METHODS

Fifty-one patients with unexplained chronic cough and 27 controls were enrolled. A capsaicin cough provocation test was performed to determine cough sensitivity. Nitrosative stress in the upper airway was assessed by quantifying 3-nitrotyrosine (3-NT) immunostaining in nasal epithelial cells (NECs) and measuring nasal nitric oxide (nNO). The effect of NO on airway epithelium was investigated by measuring the levels of substance P (SP) in nasal lavage fluid and evaluating SP expression in airway epithelial cells.

RESULTS

Based on the results of the capsaicin test, patients were divided into two groups: a cough hypersensitivity (CHS) group and a normal cough sensitivity (NCS) group. The levels of 3-NT immunoreactivity in NECs were significantly higher in CHS (49 ± 2.9%) than in NCS (27 ± 3.3%) and controls (12 ± 1.6%), a pattern that was also reflected in the values of nNO (350 ± 43, 215 ± 23, and 138 ± 23 ppb in CHS, NCS, and controls, respectively). SP concentration was also elevated in nasal lavage fluids from CHS (746 ± 28 pg/mL) compared with that from NCS (624 ± 40 pg/mL) and controls (526 ± 41 pg/mL). SP expression in airway epithelial cells was greatly enhanced by exposure to NO donor, which was attenuated by pretreatment with either NO scavenger or NO synthase inhibitor.

CONCLUSION

Increased nitrosative stress in the upper airway may play a role in the pathogenesis of unexplained chronic cough with CHS through enhanced secretion of SP.

EAACI consensus statement for investigation of work-related asthma in non-specialized centres

Work-related asthma (WRA) is a relevant problem in several countries, is cause of disability and socioeconomic consequences for both the patient and the society and is probably still underdiagnosed. A correct diagnosis is extremely important to reduce or limit the consequences of the disease. This consensus document was prepared by a EAACI Task Force consisting of an expert panel of allergologists, pneumologists and occupational physicians from different European countries. This document is not intended to address in detail the full diagnostic work-up of WRA, nor to be a formal evidence-based guideline. It is written to provide an operative protocol to allergologists and physicians dealing with asthma useful for identifying the subjects suspected of having WRA to address them to in-depth investigations in a specialized centre. No evidence-based system could be used because of the low grade of evidence of published studies in this area, and instead, 'key messages' or 'suggestions' are provided based on consensus of the expert panel members.

Diagnostic utility of exhaled breath condensate analysis in conjunction with specific inhalation challenge in individuals with suspected work-related asthma

BACKGROUND

Establishing the role of exhaled breath condensate (EBC) analysis in work-related asthma (WRA), and more specifically, in conjunction with specific inhalation challenge (SIC), is difficult.

OBJECTIVE

To measure EBC pH, and nitrite/nitrate concentrations before and after SIC in individuals with suspected WRA exposed to either high-molecular-weight (HMW) or low-molecular-weight (LMW) agents and evaluate whether these changes are useful to distinguish between occupational asthma (OA) and work-exacerbated asthma (WEA).

METHODS

One hundred twenty-five consecutive workers undergoing SIC were enrolled. Exhaled breath condensate was collected at the end of the baseline day and 24 hours after exposure to the offending agent. In all EBC samples, pH was measured, and nitrite and nitrate concentrations were determined.

RESULTS

Specific inhalation challenge was positive in 66 individuals, who were then diagnosed with OA. Work-exacerbated asthma was diagnosed in 14, and in 45 patients establishing a direct relationship between the symptoms and work exposure was not possible. In patients with WEA, EBC pH values after SIC were significantly lower than those before SIC (P = .0047). Using the receiver operating characteristic (ROC) curve, we found that an EBC pH decrease of greater than 0.4 units after SIC achieved the most satisfactory sensitivity 79% (confidence interval [CI]: 49-94) and specificity of 100% (CI: 68-100), considering only patients with asthma and without OA. A decrease in EBC pH of 0.4 or more common in those exposed to HMW agents (8/19, 42%) than in those exposed to LMW agents (7/47, 15%).

CONCLUSIONS

Exhaled breath condensate pH in conjunction with SIC may be useful for diagnosing WEA.

Irritative effects of vapours and aerosols of bitumen on the airways assessed by non-invasive methods

Irritative effects caused by vapours and aerosols of bitumen were assessed by non-invasive methods including spirometry, nasal lavage fluid (NALF) and induced sputum (IS) in a cross-shift study comparing 320 bitumen-exposed workers with 118 road construction workers as the reference group. Lung function parameters, forced vital capacity (FVC) and forced expiratory volume in one second (FEV(1)) were within normal ranges in both the reference and the bitumen-exposed groups pre- and post-shift with marginally lower values in smokers of both groups. During the shift, a slight decline in FEV(1) and FVC was observed in the bitumen-exposed group independent of their smoking habits, whereas in the non-smoking reference group, the decline in FEV(1) was not observed. No significant differences between bitumen-exposed workers and the reference group and no significant shift effect were observed on the upper airways using NALF analysis. The IS concentrations of interleukin (IL)-8, total protein and matrix metalloproteinase-9 were significantly higher in bitumen-exposed workers than in the reference group. However, the concentration of these three biomarkers in the IS samples, which are indicators of inflammatory effects on the lower airways of bitumen-exposed workers, was already higher in exposed workers before shift and did not show an increase during the shift. Therefore, the key finding of this aspect of the Human Bitumen Study is the detection of potentially (sub-) chronic irritative inflammatory effects in the lower airways of bitumen-exposed workers.

Role of eosinophils and their clinical significance in allergic inflammation

Eosinophils are believed to play roles in the pathophysiology of allergic inflammation, such as bronchial asthma. However, recent studies on anti-interleukin-5 monoclonal antibody treatment of asthmatic patients raised the possibility that eosinophils may play only a limited role. More recent studies established that eosinophils are essentially involved in the development of airway remodeling. Moreover, it is theoretically conceivable that eosinophils are a cellular source of lipid mediators, such as cysteinyl leukotrienes or platelet-activating factor in asthma. Even in the absence of interleukin-5, it is likely that the 'T-helper Type 2 network', including a cascade of vascular cell adhesion molecule-1, intercellular cell adhesion molecule-1, CC chemokines, granulocyte-macrophage colony-stimulating factor, for example, can maintain sufficient eosinophilic infiltration and effector functions, such as superoxide anion generation and degranulation. Long-term studies, wherein tissue eosinophils are eliminated effectively will be required to establish the exact roles of these cells in asthma. Finally, the authors will demonstrate that eosinophils have the potential for not only playing detrimental roles but also beneficial ones.

Noninvasive methods for assessment of airway inflammation in occupational settings

The present document is a consensus statement reached by a panel of experts on noninvasive methods for assessment of airway inflammation in the investigation of occupational respiratory diseases, such as occupational rhinitis, occupational asthma, and nonasthmatic eosinophilic bronchitis. Both the upper and the lower airway inflammation have been reviewed and appraised reinforcing the concept of 'united airway disease' in the occupational settings. The most widely used noninvasive methods to assess bronchial inflammation are covered: induced sputum, fractional exhaled nitric oxide (FeNO) concentration, and exhaled breath condensate. Nasal inflammation may be assessed by noninvasive approaches such as nasal cytology and nasal lavage, which provide information on different aspects of inflammatory processes (cellular vs mediators). Key messages and suggestions on the use of noninvasive methods for assessment of airway inflammation in the investigation and diagnosis of occupational airway diseases are issued.

EAACI position paper on occupational rhinitis

The present document is the result of a consensus reached by a panel of experts from European and non-European countries on Occupational Rhinitis (OR), a disease of emerging relevance which has received little attention in comparison to occupational asthma. The document covers the main items of OR including epidemiology, diagnosis, management, socio-economic impact, preventive strategies and medicolegal issues. An operational definition and classification of OR tailored on that of occupational asthma, as well as a diagnostic algorithm based on steps allowing for different levels of diagnostic evidence are proposed. The needs for future research are pointed out. Key messages are issued for each item.

Lower airway disease in asthmatics with and without rhinitis

STUDY OBJECTIVES

The purpose of this study was to determine if asthma with rhinitis and asthma without rhinitis represent distinct forms of disease.

DESIGN

We performed a prospective cross-sectional study.

PARTICIPANTS

The study included healthy controls, participants with asthma without rhinitis, and participants with both asthma and rhinitis. Interventions We compared lung function and airway inflammation between the three groups of participants.

RESULTS

We recruited 32 participants: 12 normals, 8 asthmatics without rhinitis, and 12 with rhinitis. Compared to asthmatics with rhinitis, asthmatics without rhinitis had more severe airflow limitation (FEV(1)/FVC = 60.6% [IQR = 22.8] vs. 74.8% [IQR = 7.8] and fewer induced sputum eosinophils (2.8 [IQR = 5.8] and 9.6 [IQR = 23.8], respectively). Sputum interleukin-6 correlated inversely with lung function measured by postbronchodilator FEV(1) in the study cohort (Spearman correlation coefficient = -0.55, p < 0.01).

CONCLUSIONS

Asthmatics without rhinitis tend to have lower lung function and less eosinophilic inflammation in the lung. This small study suggests that asthmatics without rhinitis represent a distinct phenotype of asthma in which low lung function is dissociated from eosinophilic cellular inflammation, and it suggests that larger studies addressing this phenotype are warrented.

Indices of lower airway inflammation in children monosensitized to house dust mite after nasal allergen challenge

BACKGROUND

There are few available data assessing the united airway disease and its systemic aspects in children. With this study, we aimed to investigate the inflammation markers of upper and lower airways before and after nasal allergen challenge in mite sensitive children with different clinical expression of the allergic disease.

METHODS

Four study groups were formed: rhinitis only, without bronchial hyper-responsiveness (R, n = 10), rhinitis with asthma (R + A, n = 22), atopic asymptomatics (AA, n = 8) and nonallergic healthy controls (C, n = 10). Blood eosinophils, nasal and sputum eosinophils, sputum eosinophil cationic protein (ECP) and cys-LTs, and serum ECP levels were measured before and 24 h after nasal allergen challenge.

RESULTS

The groups were comparable in terms of age and gender. Cumulative symptom scores recorded during and 1 h after nasal challenge were not significantly different between patients with R, R + A and AA groups. At T(24), the children belonging to R, R + A and AA showed significant increases in nasal eosinophils (P < 0.01, P < 0.001, and P = 0.01, respectively), sputum eosinophils (P = 0.01, P < 0.001, and P < 0.05, respectively) and blood eosinophils (P < 0.01, P < 0.001, and P < 0.05, respectively). Similarly, increases in sputum ECP (P < 0.01, P < 0.001, and P = 0.07, respectively) and sputum cys-LT levels (P = 0.07, P < 0.001, and P < 0.05, respectively) were detected in children belonging to these three groups at T(24). Sputum eosinophils significantly correlated with blood eosinophils (r = 0.54, P < 0.001) and sputum ECP (r = 0.58, P < 0.001) at T(24).

CONCLUSIONS

This study showed that nasal allergen challenge increased markers of eosinophilic inflammation in both upper and lower airways of children monosensitized to mites, even before the onset of clinical symptoms.

Reproducibility of Nasal Lavage in the Context of the Inhalation Challenge Investigation of Occupational Rhinitis

Background

The nasal lavage (NAL) method is increasingly used to assess changes in upper airways inflammation in the investigation of occupational rhinitis (OR). A good reproducibility of the method is fundamental to accurately assess changes in markers of inflammation in nasal secretions before and after inhalation challenges. The main objective of this study was to assess the short-term reproducibility of cells and cellular markers of inflammation in NAL in the setting of specific inhalation challenge (SIC) investigating OR. An ancillary objective was to assess the reproducibility of NAL in the context of two different SIC methodologies.

Methods

Twenty-five subjects attended the laboratory for 2 separate days of NAL performed within the same week. On the first visit subjects underwent NAL before a SIC sham session and on the second visit before a SIC with the active agent. These prechallenge NAL measurements obtained on both days were used to analyze the reproducibility of the NAL method.

Results

The reproducibility for cell differential counts was satisfactory for neutrophils (intraclass correlation coefficient [ICC] = 0.68), for eosinophils (ICC = 0.95), for macrophages (ICC = 0.77), and for epithelial cells (ICC = 0.73). The reproducibility of total cell counting was poor (ICC = 0.12). The reproducibility of ECP concentrations was satisfactory (ICC = 0.67). Eosinophil counts were reproducible in the context of two different challenge methodologies.

Conclusion

The NAL method was shown to be sufficiently reproducible to be considered useful for the monitoring of upper airways inflammation during the investigation of OR by SIC.

Quantitative analysis of immunoglobulin E reactivity profiles in patients allergic or sensitized to natural rubber latex (Hevea brasiliensis)

BACKGROUND

Characterized native and recombinant Hevea brasiliensis (rHev b) natural rubber latex (NRL) allergens are available to assess patient allergen sensitization profiles.

OBJECTIVE

Quantification of individual IgE responses to the spectrum of documented NRL allergens and evaluation of cross-reactive carbohydrate determinants (CCDs) for more definitive diagnosis.

METHODS

Sera of 104 healthcare workers (HCW; 51 German, 21 Portuguese, 32 American), 31 spina bifida patients (SB; 11 German, 20 Portuguese) and 10 Portuguese with multiple surgeries (MS) were analysed for allergen-specific IgE antibody (sIgE) to NRL, single Hev b allergens and CCDs with ImmunoCAP technology.

RESULTS

In all patient groups rHev b 5-sIgE concentrations were the most pronounced. Hev b 2, 5, 6.01 and 13 were identified as the major allergens in HCW and combined with Hev b 1 and Hev b 3 in SB. In MS Hev b 1 displayed an intermediate relevance. Different sIgE antibody levels to native Hevea brasiliensis (nHev b) 2 and rHev b 6.01 allowed discrimination of SB with clinical relevant latex allergy vs. those with latex sensitization. Sensitization profiles of German, Portuguese and American patients were equivalent. rHev b 5, 6.01 and nHev b 13 combined detected 100% of the latex-allergic HCW and 80.1% of the SB. Only 8.3% of the sera showed sIgE response to CCDs.

CONCLUSIONS

Hev b 1, 2, 5, 6.01 and 13 were identified as the major Hev b allergens and they should be present in standardized latex extracts and in vitro allergosorbents. CCDs are only of minor relevance in patients with clinical relevant latex allergy. Component-resolved diagnostic analyses for latex allergy set the stage for an allergen-directed immunotherapy strategy.

Feasibility of nasal epithelial brushing for the study of airway epithelial functions in CF infants

BACKGROUND

For a better understanding of the early stages of cystic fibrosis (CF), it is of major interest to study respiratory epithelial cells obtained as early as possible. Although bronchoalveolar lavage has been proposed for this purpose, nasal brushing, which is a much less invasive technique, has seldom been used in CF infants. The aim of the present study was to examine in a few infants the feasibility of a nasal brushing technique for studies of airway epithelial functions in very young CF infants.

METHODS

In 5 CF (median age 12, range 1-18 months) and 10 control infants (median age 5, range 1-17 months), a nasal brushing was performed by means of a soft sterile cytology brush, after premedication with oral paracetamol (15 mg/kg body weight) and rectal midazolam (0.2 mg/kg body weight). Samples were used for microbiological, cytological and functional studies.

RESULTS

The procedure was well tolerated. Number of cells collected was similar in CF and non-CF patients (CF: median 230x10(3), range 42x10(3)-900x10(3); non-CF: median 340x10(3), range 140x10(3)-900x10(3)). Median number of viable cells was 67% (range 31-84%). Freshly obtained samples were successfully used for studies of ciliary beating frequency and cAMP-dependent chloride efflux. In 7 out of 17 cell cultures, confluence was obtained (CF: 2 out of 7; non-CF: 5 out of 10). The feasibility of studying protein release and mRNA expression of IL-8, IL-6 and TNF-alpha, under basal conditions and after stimulation by Pseudomonas aeruginosa, was demonstrated.

CONCLUSIONS

By means of a simple nasal brushing technique easily performed and well tolerated, it is feasible, in infants, to harvest respiratory cells in sufficient amounts to study the airway epithelium using a broad range of techniques including cell culture.

A latex-induced allergic airway inflammation model in mice

Latex allergy is important due to serious health impacts and widespread use of its products. Latex allergic reactions can be induced in skin and mucosal surfaces including the respiratory tract. The development of murine models of allergic airway inflammation has provided a framework to dissect out the cellular and molecular mechanisms of allergic respiratory inflammation. In this study we have developed a new mouse model of latex allergic airway inflammation using aerosol inhalation. The allergic inflammatory responses were characterized in this model. Mice were injected intraperitoneally with 0, 10, 50, or 200 microg of latex extract and their serum anti-latex IgE titers were determined. In the second stage, a standard protocol of inhalation was designed and three doses of latex extract solutions including 1%, 0.1%, and 0.01% were used to induce allergic airway inflammation. Bronchoalveolar lavage cytokines (IL-5 and IL-13) and serum anti-latex IgE and IgG(1) titers were determined by ELISA. Eosinophil levels in lung, peripheral blood, bronchoalveolar lavage and bone marrow were also evaluated. Histological analysis of lung tissue was also performed after latex inhalation. The aerosol inhalation of 1% latex allergens solution and presensitization with 50 mug of latex in this study resulted in the development of allergic airway inflammation characterized by elevated allergen specific IgE and IgG(1), peripheral blood, bronchoalveolar lavage and bone marrow eosinophilia. Histological analysis of the lung revealed an inflammatory response characterized by eosinophil accumulation. Elevated levels of Th2 cytokines IL-5 and IL-13 also were shown in bronchoalveolar lavage samples. These studies demonstrate that sensitization and subsequent aerosol inhalational challenge of latex allergen extract promotes allergic airway inflammation characterized by elevated IL-5 and IL-13 and eosinophils.

Irritative effects of fumes and aerosols of bitumen on the airways: results of a cross-shift study

Possible health hazards of fumes and aerosols of bitumen are in discussion, and data on their adverse effects on human airways under current exposure conditions are limited. To assess the irritative effects of exposure to fumes and aerosols of bitumen on the airways, a cross-sectional cross-shift study was conducted including external and internal exposure measurements, spirometry and especially non-invasive methods like nasal lavage collection and induction of sputum in order to identify and evaluate more precisely inflammatory process in the upper and lower airways. The cross-shift study comprised 74 mastic asphalt workers who were exposed to fumes and aerosols of bitumen and 49 construction workers without this exposure as reference group. Questionnaire, spirometry, ambient monitoring and urinary analysis were performed. Humoral and cellular parameters were measured in nasal lavage fluid (NALF) and induced sputum. For data analysis, a mixed linear model was performed on the different outcomes with exposure group, time of measurement (pre-, post-shift), current smoking, German nationality and age as fixed factors and subjects as random factor. Based on personal exposure measurements during shift, mastic asphalt workers were classified into a low (< or =10 mg/m(3); n = 46) and a high (>10 mg/m(3); n = 28) exposure group. High exposure was accompanied by significant higher urinary post-shift concentrations of 1-hydroxypyrene and the sum of hydroxyphenanthrenes. Acute respiratory symptoms were reported more frequently in the high exposure group after shift. Significant cross-shift declines in lung function parameters (forced expiratory volume in 1 s [FEV(1) (% predicted)] and forced vital capacity [FVC (% predicted)]) were measured in mastic asphalt workers. Pre-shift FEV(1) (% predicted) and FVC (% predicted) were higher in the low exposure group. In pre- and post-shift NALF samples, interleukin (IL)-1beta-, IL-8- and total protein concentrations were lower in the low exposure group compared to the reference and the high exposure group. Pre- and post-shift neutrophil percentages in both nasal and sputum samples were also lower in the low exposure group. Significantly higher pre- and post-shift sputum concentrations of IL-8, IL-6, nitrogen oxide (NO) derivatives and total protein were detected especially in highly exposed workers. Irritative effects of exposure to fumes and aerosols of bitumen on the upper and lower airways were apparent, especially in mastic asphalt workers with exposure above 10 mg/m(3).

Small nonspecialized farming as a protective factor against immediate-type occupational respiratory allergy?

BACKGROUND

In Poland small, nonspecialized farms, growing different crops and raising usually a few animals of various species constitute the majority.

OBJECTIVE

The aim of the case-control study was to evaluate the risk factors of work-related respiratory symptoms and occupational asthma and/or rhinitis in Polish farmers and investigate whether the farming characteristics may have influence on the prevalence of atopy and allergic diseases.

METHODS

The study groups comprised 100 cases who were farmers reporting work-related asthmatic and/or rhinitis symptoms from randomly selected family doctors practices (80 of 353) and 102 healthy controls. All subjects were examined by means of a questionnaire, skin prick tests (SPT) to common and occupational allergens, total serum immunoglobulin (Ig)E level and the presence of specific IgE and allergen-specific inhalation challenge tests were performed. The provocation tests were monitored with the spirometry, histamine challenge test and evaluation of nasal symptoms score and nasal washings.

RESULTS

Respiratory allergic disease was recognized in 68 symptomatic patients, including 41 cases because of occupational allergens (asthma n=38, rhinitis n=41). Step-wise logistic regression analysis confirmed the protective role of small farms against the development of work-related symptoms (OR 0.23; 95% CI 0.11, 0.47) as well as the significance of positive SPT to cereals (OR 5.55; 95% CI 1.6, 19.21) and storage mites (OR 3.73; 95% CI 1.27, 10.96) as a risk factor of these symptoms. Cereal farming (OR 13.75; 95% CI 2.39, 78.83) and positive SPT to cereals (OR 26.92; 95% CI 5.33, 135.9) and storage mites (OR 44.07; 95% CI 8.40, 231.1) were found to be significant risk factors of occupational asthma and/or rhinitis.

CONCLUSIONS

Cereal farming and hypersensitivity to cereals plays the significant role in the development of occupational asthma among Polish farmers. It also seems that working on small farms may protect farmers against work-related respiratory symptoms that are mostly because of allergy.

Cytokine expression in allergic inflammation: systematic review of in vivo challenge studies

BACKGROUND

Allergic inflammatory responses are driven by cells of the immune system that rely on cytokines to regulate the activity of other immune and structural cells.

OBJECTIVE

To review published studies to (1) identify cytokines consistently increased after allergen challenge in atopic patients and (2) investigate temporal variation in cytokine expression.

METHODS

A PUBMED systematic search was used to extract data from studies involving analysis of cytokine expression in fluids or biopsies following in vivo allergen challenge in atopic patients.

RESULTS

Data were extracted from 82 studies. There were no consistent reports of cytokine protein increase in fluids of patients at 0-1 h after challenge. At 4-12 h, the chemokines eotaxin, macrophage inflammatory protein-1alpha, RANTES (regulated on activation normal T cell expressed and secreted) and interleukin (IL)-8 have all been consistently reported to be up-regulated. At 18-24 h after challenge, the lymphokines IL-4, IL-5 and IL-13, as well as the pro-inflammatory cytokines granulocyte-macrophage colony-stimulating factor, tumour necrosis factor-alpha and IL-6 are consistently increased when compared with the respective control value. There were no reports of up-regulation in interferon-gamma protein and mRNA and in IL-2 mRNA.

CONCLUSION

The expression of granulocyte-macrophage colony-stimulating factor is consistently increased in tissues at 4-12 h after challenge. The influence of this cytokine on antigen capture and presentation by dendritic cells should be further investigated. Additionally, allergen challenge studies are needed that investigate the expression of macrophage-derived chemokine and thymus-regulated and activation-regulated chemokine in tissues of atopic patients. Blocking the effects of these lymphocyte-specific chemokines might provide new therapeutic approaches for the control of allergic inflammation.

Management of occupational allergy to natural rubber latex in a medical center: the importance of quantitative latex allergen measurement and objective follow-up

When our employees began coming to the Occupational Health Service, Dermatology, and Allergy Clinics with symptoms of allergy to rubber gloves 12 years ago, the Mayo Clinic initiated 3 responses. (1) The Allergic Disease Research Laboratory adapted well-established technology to measure both the IgE antibody specific to natural rubber allergens, and by use of this IgE antibody, the allergens in rubber products and in the air of the workplace. (2) The Division of Allergic Diseases and Internal Medicine reviewed the prevalence and severity of the problem. (3) The Clinical Practice Committee appointed a multidisciplinary task force to implement measures to reduce exposure. The 3 sections of this article describe the Mayo Clinic's experience of successful control of this occupational health problem. Use of only gloves with low or undetectable allergen content greatly reduced the concentration of allergen in the work site, reduced the number of new cases of occupational allergy to rubber, and allowed individuals with latex allergy to work at their usual jobs.

Latex hypersensitivity: personal data and review of the literature

Latex allergy is an increasingly common condition, because use of latex products is widespread. The reactions to latex manufactures can be classified as allergic and non-allergic, these are the most common. Latex proteins are responsible for immediate IgE-mediated hypersensitivity allergic reactions. Symptoms range from rhinitis, conjunctivitis and urticaria to anaphylactic shock. Chemical additives can cause allergic contact dermatitis. The clinical symptoms of latex allergy could arise from direct contact with latex products, but may also result from inhalation of airborne allergens. Subpopulations at particular risk include: atopics, children with spina bifida or individuals who required frequent surgical instrumentations, health care workers, and all persons who have regular contact with latex products. Diagnosis of allergy is based initially on history: search for specific serum IgE, skin prick test and provocation test may confirm the suspicion. The most effective strategy in the treatment of latex allergy is avoidance, however this is virtually impossible, given large number of latex products we encounter since childhood. In this paper we review the current state of knowledge concerning latex allergy, including the clinical spectrum, identified allergens, the cross-reactions regarding the latex-fruit syndrome, diagnostic procedures and preventive measures. Several personal data increase awareness on this issue.

Occupational asthma and rhinitis due to glutaraldehyde: changes in nasal lavage fluid after specific inhalatory challenge test

BACKGROUNDd: Glutaraldehyde (GA) is a known respiratory sensitizers, and some studies have reported occupational asthma in exposed workers. Specific changes in nasal lavage fluid (NLF) induced by high-molecular-weight allergen provocation in sensitized subjects were described previously. The purpose of this study was to evaluate the changes in cytogram, protein content, eosinophil cationic protein (ECP), and mast-cell tryptase concentrations in NLF after GA inhalation challenge in patients with a positive history of GA-induced asthma and late or dual asthmatic response due to exposure to low-level GA.

METHODS

A single-blind, placebo-controlled study was performed on 11 health workers with occupational asthma and rhinitis due to GA. The control groups comprised 10 atopic subjects with perennial asthma and rhinitis and 10 healthy ones. A "nasal pool" technique was used to evaluate the examined parameters in nasal washings before and 30 min, 4 h, and 24 h after the inhalatory provocation with GA and placebo.

RESULTS

There was a significant increase in eosinophil number and percentage, and albumin, ECP, and tryptase concentrations in NLF from patients with occupational asthma and rhinitis when compared to controls.

CONCLUSIONS

The results indicate the immunologic mechanism of GA-induced asthma and the applicability of the "nasal pool" technique as the diagnostic procedure in GA-induced airway allergy.

Natural rubber latex allergy and asthma

Allergic responses to natural rubber latex (NRL) continue to be reported. In adults, the major exposure is in the occupational setting, especially in relation to NRL glove use by health care workers. Issues addressed over the past year include improving diagnostic methods for NRL allergy and characterization of NRL allergens relevant to various exposure groups and evaluating strategies for prevention and early detection of NRL allergy. Assessment of in vitro tests show good intertest correlation but lower sensitivity compared with skin test responses. NRL allergens have been further characterized as reported in the past year. Development of recombinant Hev b 3, a major NRL allergen relevant to children with spina bifida, enhances the likelihood for improved diagnostic reagents. Preliminary reports of primary preventive strategies suggest that avoidance of high-protein, powdered gloves in health care facilities can be cost-effective and is associated with a decline in sensitized workers.