bluuebunny/crossref_metadata_2025 huggingface dataset:
Airway eosinophilia is not a requirement for allergen‐induced airway hyperresponsiveness
Authors: Tournoy  , Kips  , Schou  , Pauwels
Published: March 2003

Background

House dust mites (HDMs) are the major source of perennial allergens causing human allergic asthma. Animal models mimicking as closely as possible the allergic features observed in human asthma are therefore interesting tools for studying the immunological and pathophysiological mechanisms involved. Especially the role of eosinophils and allergen‐specific immunoglobulin (Ig) E in the pathophysiology of airway hyperresponsiveness (AHR) remains a subject of intense debate.

Objective

To develop a mouse model of allergic airway inflammation and hyperresponsiveness based on the use of purified house dust mite allergen (Der p 1) as clinical relevant allergen. Furthermore, we studied the effects of low dose allergen exposure on the airway eosinophilia and AHR.

Methods

On day 0, C57Bl/6 mice were immunized with purified Der p 1 intraperitoneally. From day 14–20, the mice were exposed daily to a 30‐min aerosol of different concentrations of house dust mite extract.

Results

Mice, actively immunized with Der p 1 and subsequently exposed to HDM aerosols, developed AHR, eosinophil infiltration of the airways and allergen‐specific IgE. Moreover, lowering the concentration of the HDM aerosol also induced AHR and IgE without apparent eosinophil influx into the airways. Der p 1‐sensitized mice exposed to PBS produced IgE, but did not show AHR or eosinophil influx.

Conclusion

This in vivo model of HDM‐induced allergic airway changes suggests that AHR is not related to either eosinophil influx or allergen‐specific serum IgE, thereby reducing the importance of these factors as essential elements for allergic AHR.
The 18‐kDa form of cat allergen Felis domesticus 1 (Fel d 1) is associated with gelatin‐ and fibronectin‐degrading activity
Authors: Ring  , Wan  , Schou  , Kroll Kristensen  , Roepstorff  , Robinson
Published: March 2003

Background

Fel d 1, an important allergen from domestic cats, is a significant cause of asthma. In addition to directly promoting IgE synthesis, other biological activities of allergens may contribute to either allergic sensitization or the magnitude of allergic effector responses. For example, allergens that degrade proteins have been suggested to facilitate allergen presentation by increasing parallelular permeability of airways epithelium. However, little information exists to indicate whether Fel d 1 has other activities relevant to allergic responses.

Objective

To study whether Fel d 1 is associated with enzyme activity.

Methods

Fel d 1 was obtained by a rigorous purification strategy and its identity confirmed by laser desorption mass spectrometry, cleavage and sequencing. The ability of Fel d 1 to degrade gelatin, fibronectin and the artificial substrate N‐benzoyl‐FVR‐p‐nitroanilide was studied. The effect of Fel d 1 on the morphology of tight junctions in epithelial cell monolayers was also investigated.

Results

The 18‐kDa form of Fel d 1 caused degradation of denatured collagens (gelatin) and cleaved a 20‐kDa fragment from the A chain of plasma fibronectin. Catalytic activity was not altered by inhibitors of cysteine peptidases, matrix metallopeptidases or by removal of divalent cations. In contrast, aprotinin and TLCK were inhibitors of Fel d 1. The absence of a serine peptidase catalytic triad in Fel d 1, together with the stoichiometry of the inhibition of TLCK and aprotinin, suggest that their inhibitory action may be due to noncatalytic site interactions. Alternatively, highly purified Fel d 1 may be associated with an active contaminant, although none were found.

Conclusion

These results suggest that Fel d 1 is another example of a domestic allergen which is associated with enzyme activity. It remains to be established whether the activity resides in Fel d 1 itself or in an unresolved, and possibly related, protein.
Suppression of neural activity of bronchial irritant receptors by surface‐active phospholipid in comparison with topical drugs commonly prescribed for asthma
Authors: Hills  , Chen
Published: March 2003

Background

Much indirect evidence has been put forward previously in support of the concept that surface‐active phospholipid (SAPL) normally masks irritant receptors in the lungs and upper respiratory tract; but this physical barrier is deficient in asthmatics, imparting hyperresponsiveness of the bronchoconstrictor reflex.

Objective

To determine whether exogenous SAPL applied to bronchial mucosa reduces the sensitivity of irritant receptors to a standard challenge used clinically to diagnose asthma and to compare the effects with those of corticosteroids and β‐stimulation.

Methods

Nerve fibres in the vagi were monitored to record action potentials from irritant receptors identified in the upper airways of rat lungs in response to a methacholine challenge. SAPL in the form of dipalmitoyl phosphatidylcholine (PC) and phosphatidylglycerol (PG) — 7 : 3 PC:PG — was applied as a fine dry powder to enhance surface activity and, hence, chemisorption to epithelium. Comparison was also made with clinical doses of i.v. hydrocortisone and instilled salbutamol together with liquid or solid controls, as appropriate.

Results

Neural activity of irritant receptors was found to be significantly (P = 0.0018) decreased by topical SAPL by 35.8% in response to a methacholine challenge in contrast to an increase of 11.2% in response to a solid (lactose) control. Instilled salbutamol and i.v. hydrocortisone also decreased responses to the same challenge by 43.4% and 14.7%, respectively, in contrast to a liquid (saline) control which increased by 24.5%.

Conclusions

Surface‐active phospholipid has an appreciable effect upon irritant receptors in rat airways, reducing neural response to a methacholine challenge by an amount comparable to that of Salbutamol. These results support the concept of SAPL masking bronchial irritant receptors and warrant placebo‐controlled clinical trials of this dry powder as a means of controlling asthma without the side‐effects of current medication. Other possible roles discussed for the SAPL epithelial barrier include the exclusion of viruses and allergens.
Markers for early sensitization and inflammation in relation to clinical manifestations of atopic disease up to 2 years of age in 133 high‐risk children
Authors: Laan  , Baert  , Bijl  , Vredendaal  , De Waard‐Van Der Spek  , Oranje  , Savelkoul  , Neijens
Published: March 2003

Background

The combination of genetic susceptibility and environmental factors induce allergic sensitization and subsequently local inflammation, resulting in atopic manifestations.

Objective

To examine whether immunological features reflecting sensitization (total and specific IgE levels, allergen‐induced proliferative responses and skin tests) and markers of inflammation (plasma sE‐selectin and blood eosinophils) are related to the clinical expression of atopy and whether they precede atopic disease in children up to 2 years of age.

Methods

The development of these markers during the first 2 years of life was studied prospectively in 133 newborns at high risk to develop atopic disease.

Results

The prevalence of atopic disease increased from 25% at 12 months to 32% at 24 months of age. The children with food allergy at 12 months, who all had atopic dermatitis (AD), turned out to have asthma‐like disease in 40% and AD in 100% at the age of 24 months. Total IgE levels increased with time and from 12 months onward levels started to differ markedly between atopics and nonatopics. Food‐specific IgE antibodies were significantly associated with AD (relative risk [RR] = 2.39), food (RR = 1.32) and upper‐airway allergy (RR = 1.20), and house dust mite‐specific IgE antibodies with upper‐airway allergy (RR = 5.00). A positive skin test was significantly associated with AD (RR = 2.90) and food allergy (RR = 1.36). The inflammation markers investigated, were not related to the clinical expression or preceded atopic disease at 2 years of age in high‐risk children.

Conclusion

Positive skin tests and specific IgE to food or inhalant allergens were related to the clinical expression of different atopic diseases. The combination of AD and food allergy at 12 months reflected the strongest risk factor in this high risk cohort for the development of asthma‐like disease at 24 months of age.
Lessons for management of anaphylaxis from a study of fatal reactions
Authors: Pumphrey
Published: March 2003

Background

The unpredictability of anaphylactic reactions and the need for immediate, often improvised treatment will make controlled trials impracticable; other means must therefore be used to determine optimal management.

Objectives

This study aimed to investigate the circumstances leading to fatal anaphylaxis.

Methods

A register was established including all fatal anaphylactic reactions in the UK since 1992 that could be traced from the certified cause of death. Data obtained from other sources suggested that deaths certified as due to anaphylaxis underestimate the true incidence. Details of the previous medical history, the reaction and necropsy were sought for all cases.

Results

Approximately half the 20 fatal reactions recorded each year in the UK were iatrogenic, and a quarter each due to food or insect venom. All fatal reactions thought to have been due to food caused difficulty breathing that in 86% led to respiratory arrest; shock was more common in iatrogenic and venom reactions. The median time to respiratory or cardiac arrest was 30 min for foods, 15 min for venom and 5 min for iatrogenic reactions. Twenty‐eight per cent of fatal cases were resuscitated but died 3 h–30 days later, mostly from hypoxic brain damage. Adrenaline (epinephrine) was used in treatment of 62% of fatal reactions but before arrest in only 14%.

Conclusions

Immediate recognition of anaphylaxis, early use of adrenaline, inhaled beta agonists and other measures are crucial for successful treatment. Nevertheless, a few reactions will be fatal whatever treatment is given; optimal management of anaphylaxis is therefore avoidance of the cause whenever this is possible. Predictable cross‐reactivity between the cause of the fatal reaction and that of previous reactions had been overlooked. Adrenaline overdose caused at least three deaths and must be avoided. Kit for self‐treatment had proved unhelpful for a variety of reasons; its success depends on selection of appropriate medication, ease of use and good training.
Association of HLA‐DRB1*07 and DRB1*04 to citrus red mite (Panonychus citri) and house dust mite sensitive asthma
Authors: Cho S.‐H. , Kim Y.‐K. , Oh H.‐B. , Jung J.‐W. , Son J.‐W. , Lee M.‐H. , Jee H.‐S. , Kim Y.‐Y. , Min K.‐U.
Published: March 2003

Background

Specific IgE responses to allergens provide useful models for evaluating the genetic factors that control human immune responses. A recent survey demonstrated that the citrus red mite (Panonychus citri, CRM) is the most important allergen in the development of asthma in citrus farmers.

Objective

The aim of this study was to evaluate whether susceptibility or resistance to CRM‐induced asthma was associated with HLA‐DRB1 gene.

Methods

DNAs were extracted from two groups of unrelated Korean adults living around citrus farms: (1) Ninety‐one adults with CRM‐sensitive asthma; and (2) 98 exposed, healthy nonatopic controls. Genotypes of HLA‐DRB1 alleles were carried out using PCR‐based methods.

Results

Allelic frequency of HLA‐DRB1*07 was higher in the CRM‐sensitive asthmatics compared to the controls (17.6% vs 4.1%, Pc = 0.01). Conversely, the frequency of DRB1*04 was lower in the CRM‐sensitive asthmatics compared to the controls (19.8% vs 40.8%, Pc = 0.01). No significant difference was found in the distributions of the other HLA‐DRB1 gene‐encoded antigens between the two groups.

Conclusion

HLA‐DRB1 genes may be involved in the development of CRM‐induced asthma. In addition, HLA‐DR7 may increase, and DR4 decrease, the risk of developing the asthma in CRM‐exposed adults.
Increased leukotriene production by food additives in patients with atopic dermatitis and proven food intolerance
Authors: Worm M. , Vieth W. , Ehlers I. , Sterry W. , Zuberbier T.
Published: March 2003

Recently, we identified a subgroup of patients with atopic dermatitis (AD) with a clinical relevant food intolerance proven by double blind placebo controlled challenge. In search of possible pathomechanisms involved in this food intolerance, which leads to aggravation of the disease, the aim of the present study was to determine sulfidoleukotriene production in these patients using isolated leucocytes from the peripheral blood after stimulation with different food additives.

Leukotriene production of peripheral leucocytes was detected by incubation of isolated cells with the food additives at different concentrations ranging from 0.2 to 200 µg/mL after pre‐stimulation with IL‐3. Ten non‐atopic donors (A), nine AD patients of the diet responder group with negative oral provocation test against food additives (B) and nine patients of the responder group with positive reactions after the oral provocation test (C) were investigated.

In the non‐atopic group (A), no increased sulfidoleukotriene (sLT) release was observed for all food additives tested. In group B, increased sLT production was determined using tartrazine in one patient (1/9) and using nitrite in two patients (2/9), whereas sLT production remained below the cut‐off range in all patients of group B (9/9) using benzoate, metabisulfite and salicylate. By contrast, in group C increased sLT production was observed with food colour mix in 1/9, with tartrazine in 3/9, with benzoate in 4/9, with nitrite in 5/9, with salicylate in 2/9 and with metabisulfite in 1/9. However, no increased sLT concentration was determined in the presence of the tested food additives in two patients of group C.

Increased sLT production by peripheral leucocytes in the presence of single food additives was observed in the majority of patients with a proven food intolerance towards food additives proven by double‐blind‐placebo‐controlled challenges. These food additives were particulary tartrazine, benzoate and nitrite. These findings indicate that single food additives as aggravating factors in AD patients may trigger the disease through increased sLT production as a pathophysiological mechanism.
Effect of salmeterol on allergen‐induced airway inflammation in mild allergic asthma
Authors: Boulet L.‐P. , Chakir J. , Milot J. , Boutet M. , Laviolette M.
Published: March 2003

A previous study suggested that the long‐acting β2‐adrenergic agonist salmeterol (SM) had inhibitory effects on bronchial mucosal inflammation 6 hours after allergen exposure.

To further evaluate the influence of SM on allergen‐induced airway inflammation.

We studied, in a randomized, double‐blind, cross‐over trial, 16 mild asthmatic patients who had a dual asthmatic response to allergen inhalation. Subjects received 50 µg of SM or placebo (P), twice daily for 1 week each, separated by a 2‐week wash‐out period. At the end of each treatment period, after withholding SM for 24 h, they had a methacholine inhalation test (medication was resumed after the test), followed 24 h later by an AC with the concentration of allergen that had induced a LAR at baseline. Airway inflammation was assessed 24 h after the AC by bronchoalveolar lavage (BAL) (n = 16) and bronchial biopsies (n = 13).

As expected, SM improved baseline FEV1 and PC20 (P ≤ 0.009) and decreased the allergen‐induced early bronchoconstrictive response. There were no significant differences in BAL cell counts after the two treatments. On bronchial biopsies, numbers (median, mm2) of submucosal CD45 (P: 43 ± 23; SM: 161 ± 43, P = 0.031), CD45Ro (P: 37 ± 19; SM: 126 ± 41, P = 0.047) and AA1 positive cells (P: 38 ± 6, SM: 65 ± 17, P = 0.006) were significantly higher after SM than P treatment. The numbers of CD4 (P: 11 ± 10; SM: 32 ± 7, P = 0.085), HLA‐DR (P: 65 ± 30; SM: 116 ± 36, P = 0.079) and EG2 positive cells (P: 25 ± 15; SM: 38 ± 26, P = 0.09) tended to increase with SM treatment.

In summary, compared to placebo, 1 week of regular use of SM is associated with an increase in bronchial inflammatory cells 24 h after AC. This is in keeping with the recommendation that salmeterol should only be used with an anti‐inflammatory agent, particularly in the context of significant allergen exposure.
Low domestic exposure to house dust mite allergens (Der p 1) is associated with a reduced non‐specific bronchial hyper‐responsiveness in mite‐sensitized asthmatic subjects under optimal drug treatment
Authors: Maestrelli P. , Zanolla L. , Puccinelli P. , Pozzan M. , Fabbri L. M.
Published: March 2003

Background Airway inflammation in asthma causes symptoms, airflow limitation and bronchial hyper‐responsiveness. The strategy of asthma management is to reduce airway inflammation by drug treatment and avoidance of triggers, including allergens.

Objective We determined the effect of exposure to house dust mite (HDM) allergens on bronchial responsiveness in asthmatics sensitive to mites while under optimal drug treatment.

Methods We studied 71 mild to moderate HDM‐sensitive asthmatics. Drug treatment sufficient to keep asthma under control was administered to each patient for 1 year. Subjects were divided into two groups, according to the amount of Der p 1 in their bedrooms measured after standard HDM reduction measures: low Der p 1 exposure (0.64 ± 0.5 µg/g dust) (Group 1, n = 34) and high Der p 1 exposure (12.5 ± 11.4 µg/g) (Group 2, n = 37). Bronchial responsiveness to methacholine (PD20FEV1) was determined at the beginning and end of the study.

Results In Group 1, PD20FEV1 increased 2.15‐fold at the end of the study from 57 to 123 µg (P < 0.05), whereas in Group 2 no significant changes were observed. The subjects in Group 2 tended to increase the use of inhaled steroids and bronchodilators in the autumn months compared with subjects in Group 1, but the difference was not significant.

Conclusion This long‐term study shows that exposure to lower levels of mite allergens in the bedroom is associated with a decrease of bronchial hyper‐responsiveness in sensitized asthmatic subjects under optimal drug treatment.
A simple diagnostic index for asthma
Authors: Bansal A. , Farnham J. M. , Crapo R. O. , Hughes D. C. , Jensen R. L. , Cannon‐Albright L. A.
Published: March 2003

Background Asthma is becoming increasingly prevalent and a number of research groups are investigating its genetic and environmental basis.

Objective To produce a brief screening tool suitable for determining phenotype in asthma research.

Methods The scores from eight questions on symptoms and history were obtained from 678 adults and 244 children from high asthma‐incidence caucasian families. An independent physician diagnosis was also obtained with the use of a modified NHLBI‐CSGA questionnaire and pulmonary function test. Stepwise logistic regression was applied to determine which of the eight questions had greatest predictive value for asthma, and the quality of the resultant models was evaluated using an independent set of 643 adults and 239 children.

Results For adults, the most parsimonious model used responses from three of the eight questions. It had sensitivity and specificity of 0.94 and 0.96, respectively. For children, responses to two questions gave a model with sensitivity and specificity of 0.97. For both age groups, negative predictive values were above 0.87. Positive predictive values were 0.58 and 0.78 for adults and children respectively. The latter emphasize the need for conformation, by physician, of ‘affected’ calls made by this initial screen.

Conclusion The brief questionnaires described are potentially useful in a research setting, as a preliminary screening mechanism of low cost. Their use will reduce the numbers of subjects that must undergo detailed phenotyping.
Are children at high familial risk of developing allergy born into a low risk environment? The PIAMA Birth Cohort Study
Authors: Wijga A. , Smit H. A. , Brunekreef B. , Gerritsen J. , Kerkhof M. , Koopman L. P. , Neijens H. J.
Published: March 2003

Background A family history of allergy, reflecting genetic risk factors, increases the risk of developing allergic diseases, but environmental factors, especially those present in early life, also contribute to the actual development of allergic phenomena.

Objective To identify differences in lifestyle between allergic and non‐allergic parents, which may influence the prevalence of environmental risk factors in their homes.

Methods Data were collected in a Dutch birth cohort study by postal questionnaire about 2 months before and 3 months after the birth of the child.

Results Of the 3147 infants in the study 1910 (61%) had two non‐allergic parents, of 315 infants (10%) only the mother was allergic, of 787 infants (25%) only the father was allergic and 135 (4%) infants had two allergic parents. If both parents were allergic, 53% reported that allergy was taken into consideration when they furnished their home and significantly more of their homes were free of cats and free of cigarette smoke; adjusted odds ratio's for two allergic parents vs. two non‐allergic parents were 0.30 (confidence interval (CI) 0.17–0.50) for the presence of cats and 0.46 (CI 0.27–0.75) for smoking in the home. Parental allergy was also associated with having a smooth floor in the baby's bedroom and with postponement of the introduction of fruits and vegetables until the age of 26 weeks. The presence of dogs at home, the prevalence of mothers' smoking during pregnancy and the decision to breast feed were unrelated to parental allergy.

Conclusion We conclude that studies on the relationship between allergy in parents and allergy in their offspring should always consider the home environment as a potential confounder. For allergy prevention our results imply that among allergic parents there is awareness and willingness to take measures that reduce exposure to indoor allergens.
Increased nitric oxide production in nasal epithelial cells from allergic patients – RT‐PCR analysis and direct imaging by a fluorescence indicator: DAF‐2 DA*
Authors: Takeno S. , Osada R. , Furukido K. , Chen J. H. , Yajin K.
Published: March 2003

Background Nitric oxide (NO) is believed to participate in the regulation of airway clearance and non‐specific cellular immunity. Recent studies have suggested that airway epithelial cells of allergic and non‐allergic individuals may differ in their ability to produce this molecule.

Objective The aim of this study was to detect the difference in NO production in human nasal epithelial cells between normal subjects and patients with perennial allergic rhinitis (AR), and to assess the relationship between the expression of nitric oxide synthase (NOS) isoforms and the severity of the disease.

Methods Nasal epithelial cells were obtained from the inferior turbinate. The expression of mRNAs encoding constitutive endothelial NOS (eNOS) and inducible NOS (iNOS) was studied by reverse transcription‐polymerase chain reaction (RT‐PCR). Direct NO production in living cells was visualized and quantified by a fluorescent indicator, DAF‐2 DA.

Results RT‐PCR analysis demonstrated that AR patients with a RAST score of 5 or 6 showed significant increases in the levels of iNOS mRNA and slight reductions in those of eNOS mRNA. Patients with a RAST score of 2–4 also revealed the same tendency however, the difference was not significant. DAF‐2 DA imaging demonstrated that epithelial cells, especially the ciliated cells, produced a larger amount of NO than non‐epithelial inflammatory cells. Preincubation with L‐NAME resulted in an approximate 40% decrease in both groups.

Conclusion These results directly indicate that nasal epithelial cells of AR patients overall produce higher levels of NO through the concomitant expression of different NOS isoforms. Continuous NO production by the epithelial cells in normal subjects further support the hypothesis that NO derived from epithelium may play dual roles in the regulation of nasal airway clearance and in the host defense. In addition, the use of DAF‐2 DA provides a reliable method to visualize and quantify the direct NO production of living cells.
Evidence for an inflammatory pathophysiology in idiopathic rhinitis
Authors: Powe D. G. , Huskisson R. S. , Carney A. S. , Jenkins D. , Jones N. S.
Published: March 2003

Background The pathophysiology of idiopathic rhinitis is unknown but the disease is classified as being non‐allergic on the basis of negative serum IgE radioallergosorbent assay (RAST) and skin prick tests. In contrast, allergic rhinitis has a Th2 type inflammatory pathology mediated by IgE and mast cells.

Objective To test the null hypothesis that there would be no difference in the cellular infiltrate for key Th2‐associated inflammatory cells between allergic and idiopathic rhinitis.

Methods We applied strict selection criteria in the recruitment of allergic and idiopathic rhinitis cases. In contrast to previous studies which used cytology or small biopsies, we studied all layers of the mucosa by using whole, full‐thickness nasal turbinate specimens with an average length of 2.5 cm. Immunohistochemistry and in situ hybridization techniques were used to compare the distribution and cell populations of mast cells, IgE positive (IgE+) cells, eosinophils and plasma cells in perennial allergic (n = 11) and idiopathic (n = 17) rhinitis, and control nasal mucosal tissue (n = 9).

Results Mast cells and IgE+ cells were significantly increased within the epithelium of allergic and idiopathic mucosa compared to normal mucosa (P < 0.05). More IgE+ cells were present in the allergic group compared to the idiopathic group with the majority of IgE+ cells being mast cells. Both rhinitic groups showed increased eosinophilia localized to the superficial submucosa compared to normal mucosa (P < 0.05). More plasma cells were present in the allergic rhinitic tissue.

Conclusion Idiopathic and allergic rhinitic mucosa show similarities in their inflammatory infiltrate suggesting that both groups share a highly localized Th2, IgE‐mediated cellular immunopathology.
Isolated airways from current smokers are hyper‐responsive to histamine
Authors: Schmidt D. T. , Jörres R. A. , Rühlmann E. , Rabe K. F.
Published: March 2003

Epidemiological studies suggest that bronchial hyper‐responsiveness (BHR) and elevated levels of serum IgE are more frequently found in current smokers than in ex‐smokers.

Since elevated serum IgE is associated with BHR under both in vivo and in vitro conditions, we aimed to assess whether smoking affects BHR independently from IgE.

Lung resection material was obtained from 27 current smokers and 11 non‐smokers with low serum IgE (< 100 U/mL). Peripheral airways were cut into rings and incubated overnight in the presence (passively sensitized) or absence (non‐sensitized) of serum containing IgE levels above 250 U/mL. Isometric contractile responses to histamine were assessed in the organ bath.

Compared with non‐smokers, isolated airways from smokers showed significantly increased responses to histamine (P < 0.05, anova). Passive sensitization enhanced responses in both groups by about the same amount (P < 0.05, both).

In patients with low serum IgE current smoking is associated with increased bronchial responsiveness to histamine in vitro, which can be further enhanced by passive sensitization. These findings suggest that both smoking and serum IgE contribute to non‐specific airway hyper‐responsiveness.
Immunotherapy with a calcium phosphate‐adsorbed five‐grass‐pollen extract in seasonal rhinoconjunctivitis: a double‐blind, placebo‐controlled study
Authors: Leynadier F. , Banoun L. , Dollois B. , Terrier P. , Epstein M. , Guinnepain M.‐T. , Firon D. , Traube C. , Fadel R. , André C.
Published: March 2003

Background Calcium phosphate‐adsorbed allergen extracts are used for subcutaneous immunotherapy to avoid the use of aluminium adjuvants.

Objectives A double‐blind, placebo‐controlled study was performed in order to confirm the safety and assess the efficacy of a standardized five‐grass‐pollen extract adsorbed onto calcium phosphate for specific immunotherapy (IT).

Methods Twenty‐nine patients with seasonal rhinoconjunctivitis were randomized to receive either the active preparation (16 patients) or placebo (13 patients), in a 1‐year study. During the increasing dose phase, an extract ranging from 0.1 IR per ml to 50 IR per ml was administered at a rate of one subcutaneous injection per week until a maintenance dose was reached. The patients were assessed by symptom diary and rescue medications during seasonal exposure and specific nasal and skin reactivity before and after IT. Immunological parameters (specific IgE and IgG4 antibodies) were assessed before, during and after IT.

Results The overall symptoms score (mean AUC) was not significantly different between the IT group and the placebo group during grass‐pollen exposure (49.6 vs. 56, respectively). The total medication score (mean AUC) was significantly lower in the IT group than in the placebo group (11 vs. 41, P < 0.01, Mann–Whitney U‐test). The cumulative symptom/medication score was significantly lower in the IT group than in the placebo group (64.5 vs. 102.3, P < 0.05, U‐test). A significant increase in nasal reactivity threshold was observed after IT in the IT group (21. 4 IR/mL before IT vs. 63.4 IR/mL after IT, P < 0.01, Wilcoxon), whereas no significant changes were observed in the placebo group (31.0 IR/mL before IT vs. 37.7 IR/mL after IT). IT induced a significant reduction in grass pollen cutaneous reactivity in the actively treated group (P < 0.001). A significant increase in serum‐specific IgG4 antibody response was observed in the IT group (3.1% before IT vs. 10.1% after IT, P < 0.001). Nine patients in the IT group developed moderate immediate systemic reactions vs. two patients in the placebo group.

Conclusion Specific immunotherapy with calcium phosphate‐adsorbed standardized grass pollen extract was safe and effective for the treatment of patients with seasonal allergic rhinoconjunctivitis.
Identification of IgE and IgG binding epitopes on β‐ and κ‐casein in cow's milk allergic patients
Authors: Chatchatee P. , Järvinen K.‐M. , Bardina L. , Vila L. , Beyer K. , Sampson H. A.
Published: March 2003

Background Cow's milk allergy (CMA) affects 2.5% of children aged less than 2 years of age. Although β‐ and κ‐casein are considered among the major allergens responsible for CMA, no data are available on their allergenic epitopes in humans.

Objective The aim of the study was to identify IgE‐ and IgG‐binding epitopes on β‐ and κ‐casein and to determine whether the pattern of epitope recognition is associated with the natural history of CMA.

Methods Overlapping decapeptides representing the entire length of β‐ and κ‐casein, respectively, were synthesized on a cellulose‐derivatized membrane. Sera from 15 milk‐allergic children, 4–18 years of age, with high levels of specific IgE antibodies to cow's milk were used to identify IgE‐ and IgG‐binding epitopes. In addition, IgE epitopes were screened with pooled or individual sera from younger patients aged less than 3 years and who had low levels of specific serum IgE, who are likely to outgrow CMA.

Results Six major and three minor IgE‐binding epitopes, as well as eight major and one minor IgG binding regions, were identified on β‐casein. Eight major IgE‐binding epitopes, as well as two major and two minor IgG‐binding epitopes, were detected on κ‐casein. Three of the IgE binding regions on β‐casein and six on κ‐casein were recognized by the majority of patients in the older age group, but not by the younger patients.

Conclusion Information regarding the immunodominant epitopes in β‐ and κ‐casein may be important for understanding the pathophysiology and natural history of CMA. Differences in epitope recognition may be useful in identifying children who will have persistent milk hypersensitivity.
Factors related to allergic sensitization to aeroallergens in a cross‐sectional study in adults: The Copenhagen Allergy Study
Authors: Linneberg A. , Nielsen N. H. , Madsen F. , Frølund L. , Dirksen A. , Jørgensen T.
Published: March 2003

Background The factors underlying recent increases in the prevalence of respiratory allergy are largely unknown.

Objective To assess the association between allergic sensitization and several lifestyle/environmental factors.

Methods A cross‐sectional population‐based study of 15–69‐year‐olds in Copenhagen was carried out in 1990. The participation rate was 77.5% (1112/1435). Different lifestyle/environmental factors (explanatory variables) were defined based on questionnaire data. Dependent (outcome) variables were skin prick test (SPT) positivity or specific IgE positivity to common aeroallergens. Explanatory variables associated with outcome in univariate analysis (P < 0.25) were selected for multivariate analysis. Subsequently, a final model for each dependent variable was obtained by stepwise regression analysis (cut‐off for entry/removal of variables: P < 0.1).

Results Male sex, young age, low number of siblings, a positive family history of hay fever and never smoking, were independently associated with both SPT positivity and specific IgE positivity. Furthermore, SPT positivity was positively associated with alcohol consumption (dose–response relationship only), and negatively associated with previous keeping of a dog in the household. The association between alcohol consumption and SPT positivity was mainly due to the consumption of wine and remained after adjustment for educational level. Specific IgE positivity was furthermore associated with body mass index with no apparent dose–response relationship.

Conclusion Being male, young age, a positive family history of hayfever, low number of siblings and never smoking, were independently associated with allergic sensitization. In addition, the results indicated a possible relationship of alcohol consumption, body mass index and previous keeping of a dog in the household to allergic sensitization. There is a need for prospective studies of risk factors for respiratory allergy.
Heme oxygenase‐1 (HO‐1) protein induction in a mouse model of asthma
Authors: Kitada O. , Kodama T. , Kuribayashi K. , Ihaku D. , Fujita M. , Matsuyama T. , Sugita M.
Published: March 2003

Background and objective Carbon monoxide (CO) is known to be present in measurable quantities in the exhalation of asthmatic patients. Corticosteroid treatment resulted in a decrease in exhaled CO levels in asthmatic patients, raising the possibility that an increase in exhaled CO concentration reflects inflammation of the asthmatic airway. Heme oxygenase‐1 (HO‐1) protein, also called HSP32, is the rate‐limiting enzyme in the catabolism of heme to biliverdin, free iron and CO. However, it is unknown whether an expression of HO‐1 within the lung tissue is related to allergic airway inflammation. We studied the expression of HO‐1 in lung tissue and bronchoalveolar lavage cells in a mouse model of asthma.

Methods Ovalbumin (OVA)‐sensitized C57BL/6 mice were challenged with aerosolized OVA. HO‐1 positive cells were identified by immunostaining in lung tissue and bronchoalveolar lavage fluid (BALF) after the challenge.

Results HO‐1 positive cell numbers increased in the subepithelium of the bronchi after OVA challenge. In cytospin preparations from BALF after OVA challenge, HO‐1 was localized to alveolar macrophages. Inside the macrophages, HO‐1 reactivity was expressed in the cytoplasm, and the perinuclear region in particular.

Conclusion The expression of HO‐1 is increased within the lung tissue in allergic airway inflammation. Measurement of HO‐1 activity may be clinically useful in the management of asthma.
Novel dinucleotide repeat polymorphism in the first exon of the STAT‐6 gene is associated with allergic diseases
Authors: Tamura K. , Arakawa H. , Suzuki M. , Kobayashi Y. , Mochizuki H. , Kato M. , Tokuyama K. , Morikawa A.
Published: March 2003

Background T helper‐type 2 cytokines, such as interleukin‐4 (IL‐4) and IL‐13, may play a central role in allergic diseases. The protein known as ‘signal transducers and activators of transcription 6’ (STAT‐6) is a key transcription factor involved in both IL‐4‐ and IL‐13‐mediated biological responses.

Objective The objective of this study was to evaluate the possible role of the STAT‐6 gene in modulating atopy in the Japanese population.

Methods We screened all 23 exons of the STAT‐6 gene from 10 subjects for mutations by direct polymerase chain reaction (PCR) sequencing. The STAT‐6 gene polymorphisms were genotyped by PCR fragment length polymorphism analysis and PCR‐SSCP analysis. The IL‐4 receptor Q576R polymorphism was also examined by PCR‐SSCP analysis.

Results We found a novel dinucleotide repeat polymorphism in the first exon of the STAT‐6 gene. The genotypes were classified into four groups according to the number of GT repeats present, from 13 to 16. The frequency of the A1 allele (326 bp, containing 13 repeats of GT) was higher in children with allergic diseases (bronchial asthma, atopic dermatitis and/or food‐related anaphylaxis) than controls, although this was not statistically significant (P = 0.0158). In addition, a strong association between the A1 and A3 allele (containing 15 repeats of GT) heterozygote and allergic diseases was identified (P = 0.0002). However, the levels of IgE were not related to the GT repeat polymorphism in the allergic subjects. The GT repeat polymorphism was not associated with the polymorphism in the IL‐4 receptorachain gene (Q576R) and there was no association between the G2964A variant and allergic diseases.

Conclusion This suggests that genetic variation in the STAT‐6 gene may be associated with predisposition to allergic diseases.
Lack of association between atopic eczema and the genetic variants of interleukin‐4 and the interleukin‐4 receptor α chain gene: heterogeneity of genetic backgrounds on immunoglobulin E production in atopic eczema patients
Authors: Tanaka K. , Sugiura H. , Uehara M. , Hashimoto Y. , Donnelly C. , Montgomery D. S.
Published: March 2003

Background The genetic background of atopic eczema might be heterogeneous and there is a possibility that immunoglobulin (Ig)E responsiveness in patients with atopic eczema is controlled separately from the development of atopic eczema. Although both interleukin (IL)‐4 and the IL‐4 receptor α chain have an important role for IgE production and are therefore possible candidate genes for atopy, it has not been clarified whether these genes play any roles in atopic eczema patients who have normal IgE productivity.

Objective We aimed to assess whether the polymorphisms of the IL‐4 gene and the IL‐4 receptor α chain gene play any roles in atopic eczema patients, particularly in patients who have normal IgE productivity.

Method We determined the genotype with regard to polymorphisms in the genes for IL‐4 and the IL‐4 receptor α chain (− 589C/T of IL‐4; Ile50Val, Ala375Glu and Arg551Gln of IL‐4 receptor α chain) in patients with atopic eczema using the fluorogenic 5′ nuclease assay.

Results IL‐4 and the IL‐4 receptor α chain genotypes were not significantly associated with either total patients with atopic eczema or atopic eczema patients who had normal IgE productivity. The distribution of genotypes of IL‐4–589C/T differed by the serum IgE levels in patients with atopic eczema.

Conclusion These results suggest that the polymorphisms in the IL‐4 gene and the IL‐4 receptor α chain gene play no role in the development of atopic eczema in patients who have normal IgE productivity.
The proteolytic activity of the major dust mite allergen Der p 1 enhances the IgE antibody response to a bystander antigen
Authors: Gough L. , Sewell H. F. , Shakib F.
Published: March 2003

Background We have recently demonstrated that immunization of mice with proteolytically active Der p 1, the major dust mite allergen, results in a significant enhancement in total and Der p 1‐specific IgE synthesis compared to mice immunized with Der p 1 that has been irreversibly blocked with the cysteine protease inhibitors E‐64 and iodoacetamide. Thus, the demonstration that the proteolytic activity of Der p 1 enhances total IgE production, apart from increasing Der p 1‐specific IgE, suggests that this allergen may have an IgE‐specific adjuvant effect.

Objective To determine if the proteolytic activity of Der p 1 has an IgE‐specific adjuvant effect.

Methods We have examined this concept in experiments whereby ovalbumin, used as a bystander antigen, was injected alone or coinjected with either proteolytically active or inactive Der p 1 into groups of mice and IgE and IgG antibody responses were measured.

Results Here we demonstrate for the first time that the proteolytic activity of Der p 1, when given at 10‐fold higher concentration, enhances the IgE antibody response to ovalbumin.

Conclusions These findings show that the proteolytic activity of Der p 1 leads to the augmentation of IgE antibody responses to itself and to other allergens present in the microenvironment.
Increased carbon monoxide levels in the nasal airways of subjects with a history of seasonal allergic rhinitis and in patients with upper respiratory tract infection
Authors: Andersson J. A. , Uddman R. , Cardell L. O.
Published: March 2003

Background

Carbon monoxide (CO) has emerged as an endogenously produced gaseous mediator known to be involved in bronchial smooth muscle regulation. Increased amounts of CO have been found in exhaled air during asthma and lower airway inflammation. Recently CO has been shown to be produced in the nasal airways, but there are no reports of altered CO levels in nasal airways during inflammation.

Objective

This study was designed to investigate if CO levels increase in the human nasal airways during inflammatory conditions, such as allergy and upper airway respiratory tract infection (URTI).

Methods

CO was sampled separately from the upper and lower airways of 13 healthy control subjects, six patients with a history of allergic rhinitis and six patients with URTI.

Results

Nasal CO levels were increased in subjects with allergic rhinitis, compared to healthy controls (2.07 ± 0.15 ppm, n = 6 and 1.62 ± 0.08 ppm, n = 13, respectively, P < 0.01). CO levels were also increased in patients with URTI, compared to the same controls (1.92 ± 0.09 ppm, n = 6, P < 0.05). Normal levels of CO were found in air from the lower airways among subjects with allergic rhinitis, whereas corresponding levels in the URTI patients were increased.

Conclusion

The present data demonstrates that upper airway CO levels increase in parallel with different inflammatory stimuli, such as allergy and infection, suggesting a role for CO as marker or mediator of nasal inflammation.
Transforming growth factor‐bβ1 suppresses atopic dermatitis‐like skin lesions in NC/Nga mice
Authors: Sumiyoshi K. , Nakao A. , Ushio H. , Mitsuishi K. , Okumura K. , Tsuboi R. , Ra C. , Ogawa H.
Published: March 2003

Background

Atopic dermatitis is a chronic, relapsing inflammatory disorder characterized by pruritic and eczematous skin lesions. Transforming growth factor (TGF)‐β1 has been implicated in the suppression of inflammatory responses.

Objective

The purpose of this study is to determine whether TGF‐β1 suppresses skin lesions in a mouse model of atopic dermatitis.

Methods

We used the NC/Nga strain of mice as an in vivo model of atopic dermatitis. The effects of exogenous TGF‐β1 on atopic dermatitis‐like skin lesions in NC/Nga mice were evaluated clinically, histologically and immunologically.

Results

Subcutaneous injection of recombinant TGF‐β1 macroscopically suppressed eczematous skin lesions in NC/Nga mice associated with reduced serum immunoglobulin E (IgE) levels. Histological analysis showed that TGF‐β1 significantly inhibited the infiltration of inflammatory cells such as mast cells and eosinophils into the skin of NC/Nga mice. Spontaneous interferon (IFN)‐γ production from splenocytes of NC/Nga mice was down‐regulated by the treatment with TGF‐β1 and neutralizing antibody against IFN‐γ inhibited skin lesions in NC/Nga mice. The inhibitory effect of TGF‐β1 on the skin lesions lasted at least 1 week after cessation of the treatment.

Conclusion

These findings indicate that TGF‐β1 suppressed atopic dermatitis‐like skin lesions in NC/Nga mice at least in part through down‐regulation of IFN‐γ. These results suggest that TGF‐β1 may have a therapeutic potential for atopic dermatitis.
Controlled administration of penicillin to patients with a positive history but negative skin and specific serum IgE tests
Authors: Torres M. J. , Mayorga C. , Leyva L. , Guzman A. E. , Cornejo‐García J. A. , Juarez C. , Blanca M.
Published: March 2003

Background Although subjects with a positive history of immediate allergy to penicillin and negative skin test are traditionally considered to tolerate penicillin, current evidence indicates that they may develop an immediate reaction despite negative skin and serum specific IgE tests. It is thought that these patients require additional tests to confirm the diagnosis.

Objective To assess in a large group of patients with a history of immediate allergy to penicillins but with both skin test and CAP‐FEIA‐negative to classical and side chain penicillin determinants, the role of controlled administration of betalactams as a diagnostic test.

Methods A group of 330 patients with a history of immediate allergic reactions to penicillins was studied by two evaluators from the same allergy unit using the following protocol: skin tests with major and minor determinants of benzylpenicillin (benzylpenicilloyl‐poly l‐lysine and minor determinant mixture), amoxicillin and ampicillin, and determination of specific IgE antibodies to penicillins, by CAP‐FEIA, in serum. If both tests proved negative, a controlled administration of the drug was then carried out.

Results A total of 89 (27%) patients were skin test and CAP‐FEIA‐negative and therefore required controlled administration of the drug. Of these, 49 developed an immediate response and were therefore considered allergic, and the remainder had good tolerance after administration of both benzylpenicillin and amoxicillin. The clinical characteristics of this group were similar to the other allergic patients who were skin test or CAP‐FEIA‐positive, except that they were younger (P < 0.01). Twenty‐two (45%) developed a response to benzylpenicillin and 27 (55%) had a selective response to amoxicillin. Although all reactions appeared within 1 h, a positive correlation was found between the dose inducing the response and the time elapsed from drug administration, for both benzylpenicillin and amoxicillin (P < 0.001).

Conclusion These data indicate that an important number of subjects are not correctly identified if only skin tests and/or CAP‐FEIA are used and that this is particularly relevant for side chain‐specific reactions and younger subjects. This suggests that new diagnostic tests are required so as to limit the use of controlled administration.