Peribronchial Inflammation Resulting from Regulatory T Cell Deficiency Damages the Respiratory Epithelium and Disturbs Barrier Function

Regulatory T cells (Tregs) that express the transcription factor Foxp3 have a critical role in limiting inflammatory processes and tissue damage. Whether Tregs are functional in maintaining epithelial barriers and in control of tight junction expression has not yet been explored. In this study, we investigated the effect of Treg deficiency on the airway epithelial barrier in an experimental murine model in which diphtheria toxin was repeatedly injected in Foxp3-diphtheria toxin receptor (DTR) mice to deplete Tregs. This resulted in spontaneous peribronchial inflammation and led to a systemic and local increase of IL-4, IL-5, CCL3, IFN-γ, and IL-10 and a local (lung) increase of IL-6 and IL-33 and decreased amphiregulin levels. Moreover, Treg depletion increased airway permeability and decreased epithelial tight junction (protein and mRNA) expression. CTLA4-Ig treatment of Treg-depleted mice almost completely prevented barrier dysfunction together with suppression of lung inflammation and cytokine secretion. Treatment with anti–IL-4 partly reversed the effects of Treg depletion on tight junction expression, whereas neutralization of IL-6 of IFN-γ had either no effect or only a limited effect. We conclude that Tregs are essential to protect the epithelial barrier at the level of tight junctions by restricting spontaneous T cell activation and uncontrolled secretion of cytokines, in particular IL-4, in the bronchi.

Innate Lymphoid Cells Are Required to Induce Airway Hyperreactivity in a Murine Neutrophilic Asthma Model

Rationale

Non-allergic asthma is driven by multiple endotypes of which neutrophilic and pauci-granulocytic asthma have been best established. However, it is still puzzling what drives inflammation and airway hyperreactivity (AHR) in these patients and how it can be treated effectively. Recently, a potential role of the innate immune system and especially the innate lymphoid cells (ILC) has been proposed.

Objective

In this study, we investigated the effects of LPS inhalation on airway inflammation and AHR as a potential model for elucidating the pathogenesis of non-allergic asthma.

Methods

Wild-type (BALB/c), SCID, IL-17A^-/-, and Rag2^-/- γC^-/- mice were endonasally exposed to lipopolysaccharide (LPS, 2 µg) on four consecutive days. Twenty-four hours after the last exposure, AHR to methacholine was assessed. Cytokine levels and ILC subpopulations were determined in lung tissue. Cellular differential analysis was performed in BAL fluid.

Main Results

In this study, we developed a murine model for non-allergic neutrophilic asthma. We found that repeated endonasal applications of low-dose LPS in BALB/c mice led to AHR, BAL neutrophilia, and a significant increase in lung ILC3 as well as a significant increase in lung chemokines KC and MIP-2 and cytokines IL-1β, IL-17A, IL-22, and TNF. The adoptive transfer of ILC in Rag2^-/- γC^-/- mice showed that ILC played a causal role in the induction of AHR in this model. Antagonising IL-1β, but not IL-17A or neutrophils, resulted in a partial reduction in LPS-induced AHR.

Conclusion

In conclusion, we report here a murine model for neutrophilic asthma where ILC are required to induce airway hyperreactivity.

Biological Therapy in Inflammatory Bowel Disease Patients Partly Restores Intestinal Innate Lymphoid Cell Subtype Equilibrium

Patients with Crohn disease (CD) and ulcerative colitis (UC) suffer from chronic relapsing intestinal inflammation. While many studies focused on adaptive immunity, less is known about the role of innate immune cells in these diseases. Innate lymphoid cells (ILCs) are recently identified cells with a high cytokine-producing capacity at mucosal barriers. The aim was to study the impact of biological treatment on ILC in CD and UC. Patients initiating anti–tumor necrosis factor (TNF), ustekinumab, or vedolizumab treatment were prospectively followed up and peripheral and intestinal ILCs were determined. In the inflamed gut tissue of patients with inflammatory bowel disease, we found an increase of ILC1 and in immature NKp44⁻ ILC3, whereas there was a decrease of mature NKp44⁺ ILC3 when compared to healthy controls (HCs). Similar but less pronounced changes in ILC1 were observed in blood, whereas circulating NKp44⁻ ILC3 were decreased. Fifteen percent of CD patients had NKp44⁺ ILC3 in blood and these cells were not detected in blood of HCs or UC patients. Therapy with three different biologicals (ustekinumab targeting the IL-12/23 cytokines, anti-TNF and vedolizumab) partly restored intestinal ILC subset equilibrium with a decrease of ILC1 (except for ustekinumab) and an increase of NKp44⁺ ILC3. Anti-TNF also mobilized more NKp44⁺ ILC3 in circulation. As ILC1 are proinflammatory cells and as NKp44⁺ ILC3 contribute to homeostasis of intestinal mucosa, the observed effects of biologicals on ILCs might contribute to their clinical efficacy.

Fibrogenesis in chronic murine colitis is independent of innate lymphoid cells

Introduction

Insight in the pathogenesis of intestinal fibrosis is an unmet medical need in inflammatory bowel diseases. Studies in murine models and human organ fibrosis point to a potential role of innate lymphoid cells (ILC) in chronic intestinal inflammation and fibrosis.

Materials and Methods

Dextran sodium sulfate (DSS) in drinking water was used to induce chronic colitis and remodeling in C57Bl/6 wild type (WT), RAG‐deficient, RAG^−/− common γ chain deficient and anti‐CD90.2 monoclonal antibody treated RAG^−/− mice. Inflammation was scored by macroscopic and histological examination and fibrosis was evaluated by hydroxyproline quantification and histology.

Results

In RAG^−/− mice (which have a normal ILC population but no adaptive immunity), chronic intestinal inflammation and fibrosis developed similarly as in WT mice, with a relative increase in ILC2 during repeated DSS exposure. Chronic colitis could also be induced in the absence of ILC (RAG^−/−γc^−/− or anti‐CD90.2 treated RAG^−/− mice) with no attenuation of fibrosis. Importantly, clinical recovery based on weight gain after stopping DSS exposure was impaired in ILC‐deficient or ILC‐depleted mice.

Conclusion

These data argue against a profibrotic effect of ILC in chronic colitis, but rather suggest that ILC have a protective and recovery‐enhancing effect after repeated intestinal injury.

Nasal epithelial barrier dysfunction increases sensitization and mast cell degranulation in the absence of allergic inflammation

BACKGROUND

Increased epithelial permeability has been reported in allergic rhinitis, with histamine and type-2 inflammation being responsible for tight junction dysfunction. The impact of an epithelial barrier defect on allergic sensitization and mast cell (MC) degranulation remains speculative.

METHODS

Transepithelial passage of allergens was evaluated on primary human nasal epithelial cell cultures. Active sensitization was attempted by repeated intranasal ovalbumin (OVA) applications in Naïve mice. In a passive sensitization model, mice were injected with IgE to Dermatophagoides pteronyssinus (rDer p)2 and then exposed intranasally to the allergen. Chitosan was used to disrupt nasal epithelial integrity in vitro and in vivo.

RESULTS

Chitosan strongly reduced transepithelial electrical resistance and facilitated transepithelial allergen passage in cultured primary nasal epithelial cells. In vivo, intranasal chitosan affected occludin expression and facilitated allergen passage. After epithelial barrier disruption, intranasal OVA application induced higher OVA-specific IgG1 and total IgE in serum, and increased eosinophilia and interleukin-5 in bronchoalveolar lavage (BAL) compared to sham-OVA mice. Chitosan exposure, prior to rDer p2 allergen challenge in passively sensitized mice, resulted in increased β-hexosaminidase levels in serum and BAL compared to sham-rDer p2 mice. Intranasal treatment with the synthetic glucocorticoid fluticasone propionate prevented chitosan-induced barrier dysfunction, allergic sensitization, and MC degranulation.

CONCLUSION

Epithelial barrier dysfunction facilitates transepithelial allergen passage, allergic sensitization, and allergen-induced MC degranulation even in the absence of inflammatory environment. These results emphasize the crucial role of an intact epithelial barrier in prevention of allergy.

Fibrogenesis in Chronic DSS Colitis is Not Influenced by Neutralisation of Regulatory T Cells, of Major T Helper Cytokines or Absence of IL-13

Mechanisms underlying fibrogenesis in chronic colitis are largely unknown. There is an urgent need for clinical markers and identification of targets to prevent, treat and limit intestinal fibrosis. This study investigated the contribution of major T cell cytokines and T regulatory cells (Tregs) to inflammation and fibrosis induced in a model of experimental colitis by oral intake of dextran sodium sulphate (DSS) in wild type and IL-13 knock-out C57Bl/6 mice. Inflammation and fibrosis were scored by macroscopic and histological examination and fibrosis was quantified by hydroxyproline. Numbers of Tregs and IFN-γ⁺, IL-13⁺ and IL-17A⁺ CD4⁺ T helper (Th) cells in mesenteric lymph nodes increased during chronic DSS administration and mRNA for IFN-γ and IL-17 in the inflamed colon tissue was upregulated. However, antibody-mediated neutralisation of IFN-γ or IL-17A/F in a therapeutic setting had no effect on chronic intestinal inflammation and fibrosis. Antibody-mediated depletion of Tregs did not enhance fibrosis, nor did IL-13 deficiency have an effect on the fibrotic disease. These data argue against an important contribution of Tregs and of the cytokines IFN-γ, IL-13, IL-17A, IL-17F in the induction and/or control of fibrosis in this Crohn's disease like murine model.

Mucosal IL13RA2 expression predicts nonresponse to anti-TNF therapy in Crohn's disease

BACKGROUND

Ileocolonic expression of IL13RA2 has been identified as a predictive marker for nonresponsiveness to infliximab (IFX) in patients with Crohn's disease (CD).

AIM

To validate the IL13RA2 biomarker, study its anti-TNF specificity and get a better understanding of the underlying biology driving its expression.

METHODS

IL13RA2 mucosal expression was studied in a cohort of adalimumab and vedolizumab treated patients. To identify the upstream regulators of anti-TNF nonresponsiveness, weighted gene co-expression network analysis was applied on publicly available microarray data of IFX-treated patients. Selected serum proteins, including TNF, were measured prior to first IFX exposure and compared between healers and nonhealers.

RESULTS

Increased mucosal IL13RA2 expression prior to start of biological therapy was predictive for anti-TNF nonresponsiveness specifically (AUROC, area under the curve = 0.90, P < 0.001 in anti-TNF vs AUROC = 0.63, P = 0.30 in vedolizumab treated patients). In baseline biopsies, TNF-driven pathways were significantly enriched in future anti-TNF nonhealers (P = 5.0 × 10^-34 ). We found an increased baseline mucosal TNF burden in nonhealers (P = 0.02), and TNF mRNA correlated significantly with IL13RA2 expression (ρ = 0.55, P = 0.02). Baseline serum TNF levels were significantly lower in nonhealers (P = 0.04), and correlated inversely with IFX serum induction levels (r = -0.45, P = 0.002 at week 6).

CONCLUSIONS

Increased mucosal IL13RA2 expression is associated with an increased mucosal TNF burden in CD patients. In view of its specificity for prediction of anti-TNF therapy resistance, mucosal IL13RA2 expression is a potential biomarker for therapy selection and/or for the need of increased anti-TNF drug dosing.

Stepwise approach towards adoption of allergen immunotherapy for allergic rhinitis and asthma patients in daily practice in Belgium: a BelSACI-Abeforcal-EUFOREA statement

Allergic rhinitis (AR) affects 23–30% of the European population with equal prevalence reported in Belgium. Despite guidelines on the correct use of effective treatment, up to 40% of AR patients remain uncontrolled. Allergen immunotherapy (AIT) has been shown to improve the level of control up to 84% of patients being controlled by AIT. Recently, new guidelines for AIT have been published, supporting the clinical evidence for effectiveness of various subcutaneous and sublingual products for AIT in patients who are allergic to airborne allergens. AIT in AR patients not only reduces nasal and/or ocular symptoms but also induces tolerance and has preventive potential. Adoption of AIT into daily clinical practice in Belgium and other European countries is hampered primarily by reimbursement issues of each of the single products but also by several patient- and physician-related factors. Patients need to be better informed about the effectiveness of AIT and the different routes of administration of AIT. Physicians dealing with AR patients should inform patients on tolerance-inducing effects of AIT and are in the need of a harmonized and practical guide that supports them in selecting eligible patients for AIT, in choosing evidence-based AIT products and in following treatment protocols with proven efficacy. Therefore, a stepwise and holistic approach is needed for better adoption of AIT in the real-life setting in Belgium.

Effects of Epithelial IL-13Rα2 Expression in Inflammatory Bowel Disease

Background: Mucosal IL-13 Receptor alpha 2 (IL13RA2) mRNA expression is one of the best predictive markers for primary non-responsiveness to infliximab therapy in patients with inflammatory bowel disease (IBD). The objective of this study was to understand how IL-13Rα2, a negative regulator of IL-13 signaling, can contribute to IBD pathology. Methods:IL13RA2 knockout (KO) and wild type (WT) mice were exposed to dextran sodium sulfate (DSS) in drinking water to induce colitis. Furthermore, mucosal biopsies and resection specimen of healthy individuals and IBD patients before the start of anti-tumor necrosis factor (anti-TNF) therapy were obtained for immunohistochemistry and gene expression analysis. Results: After induction of DSS colitis, IL13RA2 KO mice had similar disease severity, but recovered more rapidly than WT animals. Goblet cell numbers and mucosal architecture were also more rapidly restored in IL13RA2 KO mice. In mucosal biopsies of active IBD patients, immunohistochemistry revealed that IL-13Rα2 protein was highly expressed in epithelial cells, while expression was restricted to goblet cells in healthy controls. Mucosal IL13RA2 mRNA negatively correlated with mRNA of several goblet cell-specific and barrier genes, and with goblet cell numbers. Conclusions: The data suggest that IL-13Rα2 on epithelial cells contributes to IBD pathology by negatively influencing goblet cell recovery, goblet cell function and epithelial restoration after injury. Therefore, blocking IL-13Rα2 could be a promising target for restoration of the epithelial barrier in IBD.

Probiotics against airway allergy: host factors to consider

The worldwide prevalence of allergic diseases has drastically increased in the past decades. Recent studies underline the importance of microbial exposure for the development of a balanced immune system. Consequently, probiotic bacteria are emerging as a safe and natural strategy for allergy prevention and treatment. However, clinical probiotic intervention studies have so far yielded conflicting results. There is increasing awareness about the importance of host-associated factors that determine whether an individual will respond to a specific probiotic treatment, and it is therefore crucial to promote a knowledge-based instead of an empirical selection of promising probiotic strains and their administration regimen.In this Review, we summarize the insights from animal model studies of allergic disease, which reveal how host-related factors - such as genetic makeup, sex, age and microbiological status - can impact the outcomes of preventive or curative probiotic treatment. We explore why and how these factors can influence the results of probiotic studies and negatively impact the reproducibility in animal experiments. These same factors might profoundly influence the outcomes of human clinical trials, and can potentially explain the conflicting results from probiotic intervention studies. Therefore, we also link these host-related factors to human probiotic study outcomes in the context of airway allergies.

Immunological Alterations in Haemophiliacs Treated with Lyophilized Factor VIII Cryoprecipitate from Volunteer Donors

We studied immune function in Belgian haemophiliacs treated with Factor VIII from volunteer donors. No patient had clinical evidence of immune deficiency. We found a decrease in T-helper cells (p <0.0005), in the ratio of T-helper over T-cytotoxic/ suppressor cells (1.72 ± 0.47 versus 2.24 ± 0.82 in controls, p <0.005) and in lymphocyte responsiveness to mitogens (p <0.05).

These findings could not be linked to the amount of F VIII received over the last year, the time since last F VIII administration, circulating immune complexes (54% positive patients, 7% positive controls, p <0.005), increased ALT levels, antibodies to cytomegalo-virus (85% of the patients, 45% of the controls, p <0.005), antibodies to Epstein-Barr virus, nor to the presence of HLA-DR 5 which was found in 56% of the haemophiliacs (20% of the overall Belgian population, p <0.005).

Either F VIII induces long lasting immunological alterations unrelated to AIDS, or haemophilia is itself associated with such changes.

Cluster analysis of sputum cytokine-high profiles reveals diversity in T(h)2-high asthma patients

Background

Asthma is characterized by a heterogeneous inflammatory profile and can be subdivided into T(h)2-high and T(h)2-low airway inflammation. Profiling of a broader panel of airway cytokines in large unselected patient cohorts is lacking.

Methods

Patients (n = 205) were defined as being “cytokine-low/high” if sputum mRNA expression of a particular cytokine was outside the respective 10^th/90^th percentile range of the control group (n = 80). Unsupervised hierarchical clustering was used to determine clusters based on sputum cytokine profiles.

Results

Half of patients (n = 108; 52.6%) had a classical T(h)2-high (“IL-4-, IL-5- and/or IL-13-high”) sputum cytokine profile. Unsupervised cluster analysis revealed 5 clusters. Patients with an “IL-4- and/or IL-13-high” pattern surprisingly did not cluster but were equally distributed among the 5 clusters. Patients with an “IL-5-, IL-17A-/F- and IL-25- high” profile were restricted to cluster 1 (n = 24) with increased sputum eosinophil as well as neutrophil counts and poor lung function parameters at baseline and 2 years later. Four other clusters were identified: “IL-5-high or IL-10-high” (n = 16), “IL-6-high” (n = 8), “IL-22-high” (n = 25). Cluster 5 (n = 132) consists of patients without “cytokine-high” pattern or patients with only high IL-4 and/or IL-13.

Conclusion

We identified 5 unique asthma molecular phenotypes by biological clustering. Type 2 cytokines cluster with non-type 2 cytokines in 4 out of 5 clusters. Unsupervised analysis thus not supports a priori type 2 versus non-type 2 molecular phenotypes. www.clinicaltrials.gov NCT01224938. Registered 18 October 2010.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-017-0524-y) contains supplementary material, which is available to authorized users.

Restoring airway epithelial barrier dysfunction: a new therapeutic challenge in allergic airway disease

An intact functional mucosal barrier is considered to be crucial for the maintenance of airway homeostasis as it protects the host immune system from exposure to allergens and noxious environmental triggers. Recent data provided evidence for the contribution of barrier dysfunction to the development of inflammatory diseases in the airways, skin and gut. A defective barrier has been documented in chronic rhinosinusitis, allergic rhinitis, asthma, atopic dermatitis and inflammatory bowel diseases. However, it remains to be elucidated to what extent primary (genetic) versus secondary (inflammatory) mechanisms drive barrier dysfunction. The precise pathogenesis of barrier dysfunction in patients with chronic mucosal inflammation and its implications on tissue inflammation and systemic absorption of exogenous particles are only partly understood. Since epithelial barrier defects are linked with chronicity and severity of airway inflammation, restoring the barrier integrity may become a useful approach in the treatment of allergic diseases. We here provide a state-of-the-art review on epithelial barrier dysfunction in upper and lower airways as well as in the intestine and the skin and on how barrier dysfunction can be restored from a therapeutic perspective.

4th Pediatric Allergy and Asthma Meeting (PAAM)

WORKSHOP 4: Challenging clinical scenarios (CS01–CS06)

CS01 Bullous lesions in two children: solitary mastocytoma

S. Tolga Yavuz, Ozan Koc, Ali Gungor, Faysal Gok

CS02 Multi-System Allergy (MSA) of cystic fibrosis: our institutional experience

Jessica Hawley, Christopher O’Brien, Matthew Thomas, Malcolm Brodlie, Louise Michaelis

CS03 Cold urticaria in pediatric age: an invisible cause for severe reactions

Inês Mota, Ângela Gaspar, Susana Piedade, Graça Sampaio, José Geraldo Dias, Miguel Paiva, Mário Morais-Almeida

CS04 Angioedema with C1 inhibitor deficiency in a girl: a challenge diagnosis

Cristina Madureira, Tânia Lopes, Susana Lopes, Filipa Almeida, Alexandra Sequeira, Fernanda Carvalho, José Oliveira

CS05 A child with unusual multiple organ allergy disease: what is the primer?

Fabienne Gay-Crosier

CS06 A case of uncontrolled asthma in a 6-year-old patient

Ioana-Valentina Nenciu, Andreia Florina Nita, Alexandru Ulmeanu, Dumitru Oraseanu, Carmen Zapucioiu

ORAL ABSTRACT SESSION 1: Food allergy (OP01–OP06)

OP01 Food protein-induced enterocolitis syndrome: oral food challenge outcomes for tolerance evaluation in a Pediatric Hospital

Adrianna Machinena, Olga Domínguez Sánchez, Montserrat Alvaro Lozano, Rosa Jimenez Feijoo, Jaime Lozano Blasco, Mònica Piquer Gibert, Mª Teresa Giner Muñoz, Marcia Dias da Costa, Ana Maria Plaza Martín

OP02 Characteristics of infants with food protein-induced enterocolitis syndrome and allergic proctocolitis

Ebru Arik Yilmaz, Özlem Cavkaytar, Betul Buyuktiryaki, Ozge Soyer, Cansin Sackesen

OP03 The clinical and immunological outcomes after consumption of baked egg by 1–5 year old egg allergic children: results of a randomised controlled trial

MerrynNetting, Adaweyah El-Merhibi, Michael Gold, PatrickQuinn, IrmeliPenttila, Maria Makrides

OP04 Oral immunotherapy for treatment of egg allergy using low allergenic, hydrolysed egg

Stavroula Giavi, Antonella Muraro, Roger Lauener, Annick Mercenier, Eugen Bersuch, Isabella M. Montagner, Maria Passioti, Nicolò Celegato, Selina Summermatter, Sophie Nutten, Tristan Bourdeau, Yvonne M. Vissers, Nikolaos G. Papadopoulos

OP05 Chemical modification of a peanut extract results in an increased safety profile while maintaining efficacy

Hanneke van der Kleij, Hans Warmenhoven, Ronald van Ree, Raymond Pieters, Dirk Jan Opstelten, Hans van Schijndel, Joost Smit

OP06 Administration of the yellow fever vaccine in egg allergic children

Roisin Fitzsimons, Victoria Timms, George Du Toit

ORAL ABSTRACT SESSION 2: Asthma (OP07–OP12)

OP07 Previous exacerbation is the most important risk factor for future exacerbations in school-age children with asthma

S. Tolga Yavuz, Guven Kaya, Mustafa Gulec, Mehmet Saldir, Osman Sener, Faysal Gok

OP08 Comparative study of degree of severity and laboratory changes between asthmatic children using different acupuncture modalities

Nagwa Hassan, Hala Shaaban, Hazem El-Hariri, Ahmed Kamel Inas E. Mahfouz

OP09 The concentration of exhaled carbon monoxide in asthmatic children with different controlled stadium

Papp Gabor, Biro Gabor, Kovacs Csaba

OP10 Effect of vitamin D3 supplementation during pregnancy on risk of persistent wheeze in the offspring: a randomised clinical trial

Bo Chawes, Klaus Bønnelykke, Jakob Stokholm, Lene Heickendorff, Susanne Brix, Morten Rasmussen, Hans Bisgaard

OP11 Lung function development in childhood

Henrik Wegener Hallas, Bo Chawes, Lambang Arianto, Hans Bisgaard

OP12 Is the effect of maternal and paternal asthma different in female and male children before puberty?

Maike Pincus, Thomas Keil, Andreas Reich, Ulrich Wahn, Susanne Lau, Linus Grabenhenrich

ORAL ABSTRACT SESSION 3: Epidemiology—genetics (OP13–OP18)

OP13 Lifestyle is associated with incidence and category of allergen sensitisation: the ALADDIN birth cohort

Sara Fagerstedt, Helena Marell Hesla, Emelie Johansson, Helen Rosenlund, Axel Mie, Annika Scheynius, Johan Alm

OP15 Maternal filaggrin mutations increase the risk of atopic dermatitis in children: an effect independent of mutation inheritance

Jorge Esparza-Gordillo, Anja Matanovic, Ingo Marenholz, Anja Bauerfeind, Klaus Rohde, Katja Nemat, Min-Ae Lee-Kirsch, Magnus Nordenskjöld, Marten C. G. Winge, Thomas Keil, Renate Krüger, Susanne Lau, Kirsten Beyer, Birgit Kalb, Bodo Niggemann, Norbert Hübner, Heather J. Cordell, Maria Bradley, Young-Ae Lee

OP16 Allergic multimorbidity of asthma, rhinitis and eczema in the first 2 decades of the German MAS birth cohort

Thomas Keil, Hannah Gough, Linus Grabenhenrich, Dirk Schramm, Andreas Reich, John Beschorner, Antje Schuster, Carl-Peter Bauer, Johannes Forster, Fred Zepp, Young-Ae Lee, Renate Bergmann, Karl Bergmann, Ulrich Wahn, Susanne Lau

OP17 Childhood anaphylaxis: a growing concern

Filipe Benito Garcia, Inês Mota, Susana Piedade, Ângela Gaspar, Natacha Santos, Helena Pité, Mário Morais-Almeida

OP18 Indoor exposure to molds and dampness in infancy and its association to persistent atopic dermatitis in school age. Results from the Greek ISAAC II study

Athina Papadopoulou, Despina Mermiri, Elpida Xatziagorou, Ioannis Tsanakas, Stavroula Lampidi, Kostas Priftis

ORAL ABSTRACT SESSION 4: Pediatric rhinitis—immunotherapy (OP19–OP24)

OP19 Associations between residential greenness and childhood allergic rhinitis and aeroallergen sensitisation in seven birth cohorts

Elaine Fuertes, Iana Markevych, Gayan Bowatte, Olena Gruzieva, Ulrike Gehring, Allan Becker, Dietrich Berdel, Michael Brauer, Chris Carlsten, Barbara Hoffmann, Anita Kozyrskyj, Caroline Lodge, Göran Pershagen, Alet Wijga, Heinrich Joachim

OP20 Full symptom control in pediatric patients with allergic rhinitis and asthma: results of a 2-year sublingual allergen immunotherapy study

Zorica Zivkovic, Ivana Djuric-Filipovic, Jasmina Jocić-Stevanovic, Snežana Zivanovic

OP21 Nasal epithelium of different ages of atopic subjects present increased levels of oxidative stress and increased cell cytotoxicity upon rhinovirus infection

Styliani Taka, Dimitra Kokkinou, Aliki Papakonstantinou, Panagiota Stefanopoulou, Anastasia Georgountzou, Paraskevi Maggina, Sofia Stamataki, Vassiliki Papaevanggelou, Evangelos Andreakos, Nikolaos G. Papadopoulos

OP22 Cluster subcutaneous immunotherapy schedule: tolerability profile in children

Monica Piquer Gibert, Montserrat Alvaro Lozano, Jaime Lozano Blasco, Olga Domínguez Sánchez, Rosa Jiménez Feijoo, Marcia Dias da Costa, Mª Teresa Giner Muñoz, Adriana Machinena Spera, Ana Maria Plaza Martín

OP23 Rhinitis as a risk factor for asthma severity in 11-year old children: population-based cohort study

Matea Deliu, Danielle Belgrave, Angela Simpson, Adnan Custovic

OP24 The Global Lung Function Initiative equations in airway obstruction evaluation of asthmatic children

João Gaspar Marques, Pedro Carreiro-Martins, Joana Belo, Sara Serranho, Isabel Peralta, Nuno Neuparth, Paula Leiria-Pinto

POSTER DISCUSSION SESSION 1: Food allergy (PD01–PD05)

PD01 Allergen-specific humoral and cellular responses in children who fail egg oral immunotherapy due to allergic reactions

Marta Vazquez-Ortiz, Mariona Pascal, Ana Maria Plaza, Manel Juan

PD02 FoxP3 epigenetic features in children with cow milk allergy

Lorella Paparo, Rita Nocerino, Rosita Aitoro, Ilaria Langella, Antonio Amoroso, Alessia Amoroso, Carmen Di Scala, Roberto Berni Canani

PD04 Combined milk and egg allergy in early childhood: let them eat cake?

Santanu Maity, Giuseppina Rotiroti, Minal Gandhi

PD05 Introduction of complementary foods in relation to allergy and gut microbiota in farm and non-farm children

Karin Jonsson, Annika Ljung, Bill Hesselmar, Ingegerd Adlerbert, Hilde Brekke, Susanne Johansen, Agnes Wold, Ann-Sofie Sandberg

POSTER DISCUSSION SESSION 2: Asthma and wheeze (PD06–PD16)

PD06 The association between asthma and exhaled nitric oxide is influenced by genetics and sensitisation

Björn Nordlund, Cecilia Lundholm, Villhelmina Ullemar, Marianne van Hage, Anne Örtqvist, Catarina Almqvist

PD09 Prevalence patterns of infant wheeze across Europe

Anna Selby, Kate Grimshaw, Thomas Keil, Linus Grabenhenrich, Michael Clausen, Ruta Dubakiene, Alessandro Fiocchi, Marek Kowalski, Nikos Papadopoulos, Marta Reche, Sigurveig Sigurdardottir, Aline Sprikkleman, Paraskevi Xepapadaki, Clare Mills, Kirsten Beyer, Graham Roberts

PD10 Epidemiologic changes in recurrent wheezing infants

Herberto Jose Chong Neto, Gustavo Falbo Wandalsen, Ana Carolina Dela Bianca, Carolina Aranda, Nelson Augusto Rosário, Dirceu Solé, Javier Mallol, Luis García Marcos

PD13 A single nucleotide polymorphism in the GLCCI1 gene is associated with response to asthma treatment in children

IvanaBanic, Matija Rijavec, Davor Plavec, Peter Korosec, Mirjana Turkalj

PD14 Pollen induced asthma: Could small molecules in pollen exacerbate the protein-mediated allergic response?

Alen Bozicevic, Maria De Mieri, Matthias Hamburger

PD15 A qualitative study to understand how we can empower teenagers to better self-manage their asthma

Simone Holley, Ruth Morris, Frances Mitchell, Rebecca Knibb, Susan Latter, Christina Liossi, Graham Roberts

PD16 Polymorphism of endothelial nitric oxide synthase (eNOS) gene among Egyptian children with bronchial asthma

Mostafa M. M. Hassan

POSTER DISCUSSION SESSION 3: Mechanisms—Epidemiology (PD17–PD21)

PD17 Pregnancy outcomes in relation to development of allergy in a Swedish birth cohort

Malin Barman, Anna Sandin, Agnes Wold, Ann-Sofie Sandberg

PD18 Evolution of the IgE response to house dust mite molecules in childhood

Daniela Posa, Serena Perna, Carl-Peter Bauer, Ute Hoffmann, Johannes Forster, Fred Zepp, Antje Schuster, Ulrich Wahn, Thomas Keil, Susanne Lau, Kuan-Wei Chen, Yvonne Resch, Susanne Vrtala, Rudolf Valenta, Paolo Maria Matricardi

PD19 Antibody recognition of nsLTP-molecules as antigens but not as allergens in the German-MAS birth cohort

Olympia Tsilochristou, Alexander Rohrbach, Antonio Cappella, Stephanie Hofmaier, Laura Hatzler, Carl-Peter Bauer, Ute Hoffmann, Johannes Forster, Fred Zepp, Antje Schuster, RaffaeleD’Amelio, Ulrich Wahn, Thomas Keil, Susanne Lau, Paolo Maria Matricardi

PD20 Early life colonization with Lactobacilli and Staphylococcus aureus oppositely associates with the maturation and activation of FOXP3+ CD4 T-cells

Sophia Björkander, Maria A. Johansson, Gintare Lasaviciute, Eva Sverremark-Ekström

PD21 Genome-wide meta-analysis identifies 7 susceptibility loci involved in the atopic march

Ingo Marenholz, Jorge Esparza-Gordillo, Franz Rüschendorf, Anja Bauerfeind, David P. Strachan, Ben D. Spycher, Hansjörg Baurecht, Patricia Margaritte-Jeannin, Annika Sääf, Marjan Kerkhof, Markus Ege, Svetlana Baltic, Melanie C Matheson, Jin Li, Sven Michel, Wei Q. Ang, Wendy McArdle, Andreas Arnold, Georg Homuth, Florence Demenais, Emmanuelle Bouzigon, Cilla Söderhäll, Göran Pershagen, Johan C. de Jongste, Dirkje S Postma, Charlotte Braun-Fahrländer, Elisabeth Horak, Ludmila M. Ogorodova, Valery P. Puzyrev, Elena Yu Bragina, Thomas J Hudson, Charles Morin, David L Duffy, Guy B Marks, Colin F Robertson, Grant W Montgomery, Bill Musk, Philip J Thompson, Nicholas G. Martin, Alan James, Patrick Sleiman, Elina Toskala, Elke Rodriguez, Regina Fölster-Holst, Andre Franke, Wolfgang Lieb, Christian Gieger, Andrea Heinzmann, Ernst Rietschel, Thomas Keil, Sven Cichon, Markus M Nöthen, Craig E Pennell, Peter D Sly, Carsten O Schmidt, Anja Matanovic, Valentin Schneider, Matthias Heinig, Norbert Hübner, Patrick G. Holt, Susanne Lau, Michael Kabesch, Stefan Weidinger, Hakon Hakonarson, Manuel AR Ferreira, Catherine Laprise, Maxim B. Freidin, Jon Genuneit, Gerard H Koppelman, Erik Melén, Marie-Hélène Dizier, A. John Henderson, Young Ae Lee

POSTER DISCUSSION SESSION 4: Food allergy—Anaphylaxis (PD22–PD26)

PD22 Atopy patch test in food protein induced enterocolitis caused by solid food

Purificacion González-Delgado, Esther Caparrós, Fernando Clemente, Begoña Cueva, Victoria M. Moreno, Jose Luis Carretero, Javier Fernández

PD23 Watermelon allergy: a novel presentation

Kate Swan, George Du Toit

PD24 A pilot study evaluating the usefulness of a guideline template for managing milk allergy in primary care

Mudiyur Gopi, Tim Smith, Edara Ramesh, Arun Sadasivam

PD26 Efficacy and safety of cow’s milk oral immunotherapy protocol

Inês Mota, Filipe Benito Garcia, Susana Piedade, Angela Gaspar, Graça Sampaio, Cristina Arêde, Luís Miguel Borrego, Graça Pires, Cristina Santa-Marta, Mário Morais-Almeida

POSTER DISCUSSION SESSION 5: Prevention and treatment—Allergy (PD27–PD36)

PD27 Allergy-protection by the lactic acid bacterium Lactococcus lactis G121: mode-of-action as revealed in a murine model of experimental allergy

Stephanie Brand, Karina Stein, Holger Heine, Marion Kauth

PD29 The relationship between quality of life and morning salivary cortisol after acute bronchiolitis in infancy

Leif Bjarte Rolfsjord, Egil Bakkeheim, Johan Alm, Håvard Ove Skjerven, Kai-Håkon Carlsen, Jon Olav Hunderi, Teresa Løvold Berents, Petter Mowinckel, Karin C. Lødrup Carlsen

PD30 Randomised trial of the efficacy of MP29-02* compared with fluticasone propionate nasal spray in children aged ≥6 years to <12 years with allergic rhinitis

Ulrich Wahn, Ullrich Munzel, William Berger

PD31 10 mg of oral bilastine in 2 to 11 years old children has similar exposure to the adult therapeutic dose (20 mg)

Ulrich Wahn, Román Valiente, Valvanera Vozmediano, John C. Lukas, Mónica Rodríguez

PD33 Daily symptoms, nocturnal symptoms, activity limitations and reliever therapies during the three steps of IOEASMA programme: a comparison

Sebastiano Guarnaccia, Luigi Vitale, Ada Pluda, Emanuele D’Agata, Denise Colombo, Stefano Felici, Valeria Gretter, Susanna Facchetti, Gaia Pecorelli, Cristina Quecchia

PD34 Sensitisation to an inert aeroallergen in weaning rats and longstanding disease, in a sensitisation-tolerant and easily tolerisable rodent strain

George Guibas, Evangelia Spandou, Spyridon Megremis, Peter West, Nikolaos Papadopoulos

PD35 Bacterial and fungi exposure in school and allergic sensitisation in children

João Cavaleiro Rufo, Joana Madureira, Inês Paciência, Lívia Aguiar, Patrícia Padrão, Mariana Pinto, Luís Delgado, Pedro Moreira, João Paulo Teixeira, Eduardo Oliveira Fernandes, André Moreira

PD36 Comparative study of allergy rhinitis between two populations: children vs. adults

Adriana Izquierdo Dominguez, Antonio Valero, Joaquim Mullol, Alfonso Del Cuvillo, Javier Montoro, Ignacio Jauregui, Joan Bartra, Ignacio Davila, Marta Ferrer, Joaquin Sastre

POSTER VIEWING SESSION 1: Inflammation—Genetics—Immunology—Dermatology (PP01–PP09)

PP01 Immune profile in late pregnancy: immunological markers in atopic asthmaticwomen as risk factors for atopy in the progeny

Catarina Martins, Jorge Lima, Maria José Leandro, Glória Nunes, Jorge Cunha Branco, Hélder Trindade, Luis Miguel Borrego

PP02 The impact of neonatal sepsis on development of allergic diseases

Secil Conkar, Mehtap Kilic, Canan Aygun, Recep Sancak

PP03 Clinical overview of selective IgE deficiency in childhood

Athina Papadopoulou, Eleni Tagalaki, Lambros Banos, Anna Vlachou, Fotini Giannoula, Despina Mermiri

PP04 Inverse relationship between serum 25(ΟΗ) vitamin D3 and total IgE in children and adolescence

Athina Papadopoulou, Stavroula Lampidi, Marina Pavlakou, Maria Kryoni, Kostas Makris

PP05

PP06

PP07 Asthma control questionnaire and specific IgE in children

Snezhina Lazova, Guergana Petrova, Dimitrinka Miteva, Penka Perenovska

PP08 Features of chronic urticaria of adolescents

Aliya Klyucharova, Olesya Skorohodkina

PP09 Cutaneous mastocytosis in children: a clinical analysis of 8 cases in Greece

Dimitra Koumaki, Alkisti Manousaki, Maria Agrapidi, Lida Iatridou, Omima Eruk, Konstantinos Myridakis, Emmanouil Manousakis, Vasiliki Koumaki

POSTER VIEWING SESSION 2: Food allergy—Anaphylaxis (PP10–PP47)

PP10 Prognostic factors in egg allergy

Maria Dimou, Maria Ingemansson, Gunilla Hedlin

PP11 Evaluation of the efficacy of an amino acid-based formula in infants who are intolerant to extensively hydrolysed protein formula

Nitida Pastor, Delphine de Boissieu, Jon Vanderhoof, Nancy Moore, Kaitlin Maditz

PP12 Anaphylaxis and epinephrine auto-injector use: a survey of pediatric trainees

Adeli Mehdi, Shaza Elhassan, Carolin Beck, Ahmed Al-Hammadi

PP13 Anaphylaxis in children: acute management in the Emergency Department

Ioana Maris, Ronan O’Sullivan, Jonathan Hourihane,

PP14 Understanding Cumbrian schools preparedness in managing children at risk of anaphylaxis in order to provide training and support which will create healthy and safe environments for children with allergies

George Raptis, Louise Michaelis

PP15 A new valid and reliable parent and child questionnaire to measure the impact of food protein enterocolitis syndrome on children: the FPIES Quality of Life Questionnaire (FPIESQL), Parent and Child Short Form

Audrey DunnGalvin, Matthew Greenhawt, Carina Venter, Jonathan Hourihane

PP16 An in-depth case study investigation of the experiences of teenagers and young adults in growing up and living with food allergy with emphasis on coping, management and risk, support, and social and self-identity

Evelyn O’Regan, Duncan Cronin, Jonathan Hourihane, Anna O’Reilly, Audrey DunnGalvin

PP17 Cow’s milk protein allergy in Constantine. A retrospective study of 62 cases between 1996 and 2013

Foued Abdelaziz, Dounia Khelifi-Touhami, Nihad Selim, Tahar Khelifi-Touhami

PP18

PP19 Cow’s milk and egg oral immunotherapy in children older than 5 years

Pablo Merida, Ana Mª Plaza, Juan Heber Castellanos, Adrianna Machinena, Montserrat Alvaro Lozano, Jaime Lozano, Olga Dominguez, Monica Piquer, Rosa Jimenez, Mª Teresa Giner

PP20 Professionals’ awareness of management of Cow’s Milk Protein Allergy (CMPA) in North Wales Hospitals

Konstantinos Kakleas, Manohar Joishy, Wendmu Maskele, Huw R. Jenkins

PP21

PP22 Anaphylaxis: the great unknown for teachers. Presentation of a protocol for schools

Mercedes Escarrer, Agustín Madroñero, Maria Teresa Guerra, Juan Carlos Julia, Juan Carlos Cerda, Javier Contreras, Eulalia Tauler, Maria Jesus Vidorreta, Ana Rojo, Silvia Del Valle

PP23 Challenges facing children with food allergies and their parents in out of school activity sectors

Niamh Flynn

PP24 A review of food challenges at a Regional Irish Centre

Gary Foley, Carol Harmon, John Fitzsimons

PP25 The use of epinephrine in infants with anaphylaxis

Krasimira Baynova, Ávila Maria Del Robledo, Labella Marina

PP26

PP27

PP28 Mother’s psychological state predicts the expression of symptoms in food allergic children

Aaron Cortes, Alicia Sciaraffia, Angela Castillo

PP29 The correlation between sIgE towards tree nuts and birch pollen in a Danish Pediatric Allergy Clinic

Nanna Juel-Berg, Kirsten Skamstrup Hansen, Lars Kærgaard Poulsen

PP30 Food allergy in children: evaluation of parents’ use of online social media

Andreia Florina Nita, Ioana Valentina Nenciu, Adina Lazar, Dumitru Oraseanu

PP31 The impact of food allergy on quality of life: FAQLQ questionnaire

Rita Aguiar, Anabela Lopes, Maria J. Paes, Amélia S. Santos, M. A. Pereira-Barbosa

PP32 An unexpected cause of anaphylaxis: potato

Hatice Eke Gungor, Salih Uytun, Umit Murat Sahiner, Yasemin Altuner Torun

PP33 Is it clinical phenotype of allergic diseases determined by sensitisation to food?

Mirjana Zivanovic, Marina Atanasković-Marković

PP34

PP35 Prescribing adrenaline auto-injectors in children in 2014: the data from regional pediatricians

Tina Vesel, Mihaela Nahtigal, Andreja Obermayer-Temlin, Eva Šoster Križnik, Mirjana Maslar, Ruben Bizjak, Marjeta Tomšič-Matic, Sonja Posega-Devetak, Maja Skerbinjek-Kavalar, Mateja Predalič, Tadej Avčin

PP36 Who should have an adrenaline autoinjector? Adherence to the European and French guidelines among 121 allergists from the Allergy Vigilance Network

Guillaume Pouessel, Etienne Beaudouin, Anne M. Moneret-Vautrin, Antoine Deschildre, Allergy Vigilance Network

PP37 Anaphylaxis by Anacardium Occidentale

Marta Viñas, Bartolomé Borja, Nora Hernández, Mª José Castillo, Adriana Izquierdo, Marcel Ibero

PP38 Anaphylaxis with honey in a child

S. Tolga Yavuz, Ali Gungor, Betul Buyuktiryaki, Ozan Koc, Can Naci Kocabas, Faysal Gok

PP39 Evaluation of courses adopted to children on prevention, recognition and management of anaphylaxis

Tina Vesel, Mihaela Nahtigal

PP40 Symptomatic dust mites and shrimp allergy: three pediatric case reports

Filipa Almeida, Susana Lopes, Cristina Madureira, Tânia Lopes, Fernanda Carvalho

PP41 Poor identification rates of nuts by high risk individuals: a call for improved education and support for families

Camille Heming, Emily Garrett, Adam Blackstock, Santanu Maity, Rahul Chodhari

PP42 DAFALL: database of food allergies in the Czech Republic

Simona Belohlavkova, Eliska Kopelentova, Petr Visek, Ivana Setinova, Ivana Svarcova

PP43 Serological cross-reactivity between grass and wheat is not only caused by profilins and CCDs

Sigrid Sjölander, Nora Nilsson, Malin Berthold, Helena Ekoff, Gunilla Hedlin, Magnus Borres, Caroline Nilsson

PP44 Oil body associated proteins in children with nuts allergy. Allergens to consider in IgE-mediated nuts allergy

Loreto González Domínguez, Cristina Muñoz Archidona, Ana Moreira Jorge, Sergio Quevedo Teruel, Teresa Bracamonte Bermejo, Miriam Castillo Fernández, Fernando Pineda de la Losa, Luis Ángel Echeverría Zudaire

PP45

PP46 Protective effect of helicobacter pylori infection against food allergy in children

Olga Vrani, Antigone Mavroudi, Maria Fotoulaki, Maria Emporiadou, Kleomenis Spiroglou, Ioannis Xinias

PP47 Anaphylaxis pathway: A road tryp-tase to success?

Helyeh A. Sadreddini, Mia Warnes, Donna Traves

POSTER VIEWING SESSION 3: Miscellaneous (PP48–PP58)

PP48 Surveillance study on safety of SLIT in pediatric population

Ivana Djuric-Filipovic, Zorica Zivkovic, Snežana Zivanovic, Gordana Kostić, Đorđe Filipovic

PP49 Efficacy and safety of mixed mite subcutaneous immunotherapy among allergic rhinitis patients in the Northeastern Thailand

Sawapon Sittisomwong, Siripong Sittisomwong

PP50 Effect of inhaled beclomethasone or placebo on brain stem activity in a patient chronically treated with steroids: preliminary report

Zygmunt Podolec, Marcin Hartel, Daria Panek, Magdalena Podolec-Rubiś, Tomasz Banasik

PP51 Sensitisation to aeroallergens in patients with allergic rhinitis, asthma and atopic dermatitis in Shiraz, Southwestern Iran

Elham Abbasi, Mozhgan Moghtaderi

PP52 Referring a child for allergy test: how appropriate are we?

Phani Sanneerappa, Alina Deliu, Moosa Kutty, Nagabathula Ramesh

PP53 EBV lymphoproliferative disease and cardiac lymphoma in a STK4 deficient patient

Roya Sherkat, Mohammad Reza Sabri, Bahar Dehghan, Hamid Bigdelian, Nahid Raeesi, Mino Afshar, Hamid Rahimi, Christoph Klein

PP54 A case study: the effect of massive honeybees attack on various body parameters atopic girl including allergy

Mohemid Al-Jebouri

PP55 The role of TLR9, NLRP3 and proIL-1β in activation of antiviral innate immunity

Oxana A. Svitich, Daria O. Zubacheva, Dmitrii A. Potemkin, Ludmila V. Gankovskaya, Vitalii V. Zverev

PP56 Overnight pulse oximetry, as a screening tool to diagnose obstructive sleep apnoea. How effective is it?

Phani Sanneerappa, Elaine OB Doyle, Paul Gallagher, Nagabathula Ramesh

PP57 The presentation and management of acute urticaria and allergic reactions in children in a multi-ethnic, inner city Emergency Department (ED)

Sherine Dewlett, Kin Man, Minal Gandhi, James Pocock, Anna Gerrardhughes

PP58 Food allergens responsible for delayed-type sensitisation in atopy patch test in children diagnosed with autism spectrum disorder

Jolanta Wasilewska, Maciej Kaczmarski, Dariusz Lebensztejn

POSTER VIEWING SESSION 4: Asthma—Rhinitis (PP59–PP87)

PP59 Systematic review of incense as a trigger factor for asthma

Chandramani Thuraisingham, Davendralingam Sinniah

PP60 Increased risks of mood and anxiety disorders in children with asthma

Yue Chen, Xiaomei Mei

PP61

PP62 Asthma Control Test (ACT) and Pediatric Asthma Quality of Life Questionnaire (PAQLQ) association in children

Sebnem Ozdogan, Pinar Karadeniz, Durdugul Ayyildiz-Emecen, Ummuhan Oncul

PP63 Seasonal and gender variations in vitamin D levels in children with asthma and its association with pulmonary function tests

Sebnem Ozdogan, Gizem Sari, Sabanur Cavdar

PP64 Defining treatment response in childhood asthma: rationale and design of the Pharmacogenomics in the Childhood Asthma (PiCA) consortium

Niloufar Farzan, Susanne J. Vijverberg, Colin J. Palmer, Kelan G. Tantisira, Anke-Hilseon Maitland-van der Zee behalf of the PiCA consortium

PP65 Prevalence of asthma and allergic disease in patients with inflammatory disease compared to celiac disease

Fatma Yavuzyilmaz, Sebnem Ozdogan, Nafiye Urganci, Merve Usta

PP66 A severe case with cystic fibrosis (CF) asthma

Mehmet Hoxha, Maksim Basho

PP67 Severe asthma exacerbation complicated with pneumothorax in a child with uncontrolled asthma due to poor treatment compliance

Ioana Valentina Nenciu, Andreia Florina Nita, Adina Lazar, Alexandru Ulmeanu, Carmen Zapucioiu, Dumitru Oraseanu

PP68 Evaluation of the Pediatric Quality of Life inventory (PedsQL) asthma module among low income asthmatic children and adolescents in Sao Paolo, Brazil

Gustavo F. Wandalsen, Fernanda Monteiro, Dirceu Solé

PP69 Early initiation of specific immunotherapy in asthma patients leads to higher benefits

Blerta Lame, Eris Mesonjesi, Arjeta Sherri

PP70 Treatment resistant asthma and rhinosinusitis with recurrent pulmonary infections. Is it primary ciliary dyskinesia?

Alkerta Ibranji, Laert Gjati, Gjustina Loloci, Ardii Bardhi

PP71 The comparison of sensitisation to animal allergens in children- and adult- onset patients with asthma

Behnam Moghtaderi, Shirin Farjadian, Dorna Eghtedari

PP72 Characterisation of children less than five years with wheezing episodes in Cali, Colombia

Manuela Olaya, Laura Del Mar Vasquez, Luis Fernando Ramirez, Carlos Daniel Serrano

PP73 Evaluation of the patients with recurrent croup

Belgin Usta Guc, Suna Asilsoy, Fulya Ozer

PP74 Obesity in adolescence compromising the asthma control

Guergana Petrova, Sylvia Shopova, Vera Papochieva, Snezhina Lazova, Dimitrinka Miteva, Penka Perenovska

PP75 Sleep behavior in children with persistent allergic rhinitis

Gustavo F. Wandalsen, Jessica Loekmanwidjaja, Márcia Mallozi, Dirceu Solé

PP76 Randomised trial of the safety of MP29-02* compared with fluticasone propionate nasal spray in children aged ≥4 years to <12 years with allergic rhinitis

William Berger, Ulrich Wahn, Paul Ratner, Daniel Soteres

PP77 Safety and tolerability evaluation of bilastine 10 mg in children from 2 to 11 years of age with allergic rhinoconjunctivitis or urticaria

Zoltán Novák, Anahí Yáñez, Kiss Ildikó, Piotr Kuna, Miguel Tortajada, Román Valiente, the Bilastine Pediatric Safety Study Group

PP78 Sensitisation to Alternaria alternata: Is it a risk factor for severe rhinitis?

Susana Lopes, Filipa Almeida, Tânia Lopes, Cristina Madureira, José Oliveira, Fernanda Carvalho

PP79 Validation of the Patient Benefit Index (PBI) for the assessment of patient-related outcomes in allergic rhinitis in children

Julia Feuerhahn, Christine Blome, Meike Hadler, Efstrathios Karagiannis, Anna Langenbruch, Matthias Augustin

PP80 Efficacy of sublingual tablet of house dust mite allergen extracts in adolescents with house dust mite-associated allergic rhinitis

Michel Roux, Shinji Kakudo, Efstrathios Karagiannis, Robert K. Zeldin

PP81 Lung function improvement in a child treated with omalizumab for bronchial asthma

Anna Sokolova, Tiago Milheiro Silva

PP82 How to treat a child suffering from asthma, allergic rhinitis, allergy to peanuts and diabetes at the same time?

Snezana S. Zivanovic, Vesna Cvetkovic, Ivana Nikolic, Sonja J. Zivanovic

PP83 Nitric oxide in exhaled air in the relationship of the degree of sensitisation to aeroallergens

Snezana S. Zivanovic, Ljiljana Saranac, Ivana Nikolic, Sonja J. Zivanovic, Zorica Zivkovic

PP84 Clinical basis of diagnostic errors in pediatric asthma

Zoia Nesterenko

PP85

PP86 Childhood asthma control in Serbia and organised Asthma Educational Intervention (AEI)

Snezana Radic, Branislava Milenkovic, Spomenka Smiljanic, Milka Micic-Stanijevic, Olivera Calovic

PP87 Experience from a group of adolescents with severe allergic asthma treated with Omalizumab

Anne Marie Bro Hofbauer, Lone Agertoft

THEMATIC POSTER SESSION 1: Prevention and Treatment—Epidemiology (TP01–TP18)

TP01 A cost effective primary school asthma education program: pilot study from inner London schools

Lucy Everson, Jessica Kearney, Jonny Coppel, Simon Braithwaite, Rahul Chodhari

TP02 The prevalence of allergic diseases among 14–15 years old adolescents in two Danish birth cohorts 14 years apart

Elisabeth S. Christiansen, Henrik Fomsgaard Kjaer, Esben Eller, Charlotte G. Mørtz, Susanne Halken

TP03 Does pattern of sensitisation to phleum pratense change with age? Is it different in children with allergic rhinitis or asthma?

Cristina Román India, Ana Moreira Jorge, Loreto González Domínguez, Cristina Muñoz Archidona, Sergio Quevedo Teruel, Teresa Bracamonte Bermejo, Juana Jiménez Jiménez, Luis Echeverría Zudaire

TP04 Practicalities of prevention of peanut allergy: modelling a national response to LEAP

Cathal O’Connor, Jonathan Hourihane

TP05 Comparison of the influence of sunflower seed oil and skin care lotion on the skin barrier function of newborns: a randomised controlled trial

Varvara Kanti, Lena Lünnemann, Günther Malise, Laine Ludriksone, Andrea Stroux, Wolfgang Henrich, Michael Abu-Dakn, Ulrike Blume-Peytavi, Natalie Garcia Bartels

TP06 The effect of daily skin care on skin barrier properties in infants with dry skin and risk for atopic dermatitis

Varvara Kanti, Lena Lünnemann, Laine Ludriksone, Marianne Schario, Andrea Stroux, Ulrike Blume-Peytavi, Natalie Garcia Bartels

TP07 Change in sum total aeroallergen skin prick test wheal diameters at 6 months predicts which children will respond to subcutaneous immunotherapy by three years

Thorsten Stanley, Nicolien Brandenbarg

TP08 Are mobile apps regarding adrenaline auto-injectors accessed by adolescents for support and education in the community?

Alia Boardman, Gary McGreevy, Emily Rodger, Katherine Knight, Victoria Timms, Trisha Taylor, Gemma Scanlan, Roisin Fitzsimons

TP09

TP10 Prevention of early atopic dermatitis among low-atopy-risk infants by immunoactive prebiotics is not sustained after the first year of life

Grüber Christoph, Ulrich Wahn, Margriet van Stuivenberg, Fabio Mosca, Guido Moro, Gaetano Chirico, Christian P. Braegger, Joseph Riedler, Yalcin Yavuz, Günther Boehm

TP11

TP12

TP13 Treatment with Omalizumab in a 16-year-old Caucasian girl with refractory solar urticaria

Stefania Arasi, Giuseppe Crisafulli, Lucia Caminiti, Federica Porcaro, Giovanni Battista Pajno

TP14 Ultra-pure soft water ameliorates skin conditions of adult and child patients with atopic dermatitis

Akane Tanaka, Yaei Togawa, Kumiko Oida, Naotomo Kambe, Peter Arkwright, Yosuke Amagai, Naoki Shimojo, Yasunori Sato, Hiroyuki Mochizuki, Hyosun Jang, Saori Ishizaka, Hiroshi Matsuda

TP15 Potential adjuvant effect of immunomodulator to improve specific immunotherapy in asthmatic child

Wisnu Barlianto, Ery Olivianto, H. M. S. Chandra Kusuma

TP16 How can Component Resolved Diagnosis (CRD) influence in Specific Immunotherapy (SIT) prescription, in a Spanish children population

Ana Moreira Jorge, Cristina Román India, Loreto González Domínguez, Cristina Muñoz Archidona, Juana Jiménez Jiménez, Teresa Bracamonte Bermejo, Sergio Quevedo Teruel, Luis Echeverría Zudaire

TP17 Mitochondrial dysfunction in food allergy: effects of L. rhamnosus GG in a mice model of peanut allergy

Rosita Aitoro, Mariapia Mollica, Roberto Berni Canani, Giovanna Trinchese, Elena Alfano, Antonio Amoroso, Lorella Paparo, Francesco Amato, Claudio Pirozzi, Antonio Calignano, Rosaria Meli

TP18 Prediction of atopic diseases in childhood: elevated blood eosinophils in infancy in a high risk birth cohort

Siri Rossberg, Kerstin Gerhold, Kurt Zimmermann, Mohammad Zaino, Thomas Geske, Eckard Hamelmann, Susanne Lau

THEMATIC POSTER SESSION 2: Food allergy—Anaphylaxis (TP19–TP38)

TP19

TP20

TP21 Double-blind provocation tests in non-IgE mediated cow’s milk allergy and the occurrence of placebo reactions

Sarah Bogovic, Jochem van den Berg, Chantal Janssen

TP22 Gradual introduction of baked egg (BE) in egg allergic patients under 2 years old

Angela Claver

TP23 Randomised controlled trial of SOTI with raw hen’s egg in children with persistent egg allergy I: safety and efficacy of daily vs. weekly protocols of induction

Mª Flor Martin-Muñoz, C. Martorell, M. T. Belver, E. Alonso Lebrero, L. Zapatero, V. Fuentes, M. Piqué, A. Plaza, C. Muñoz, A. Martorell, Cristina Blasco, B. Villa, C. Gómez, S. Nevot, J. M. García, L. Echeverria

TP24 Randomised controlled trial of SOTI with raw hen’s egg in children with persistent egg allergy II: a randomised controlled trial to study a safer, more effective and easy to perform maintenance (daily vs. every two days) pattern of egg SOTI

Mª Flor Martin-Muñoz, C. Martorell, M. T. Belver, E. Alonso Lebrero, L. Zapatero, V. Fuentes, M. Piqué, A. Plaza, C. Muñoz, A. Martorell, Cristina Blasco, B. Villa, C. Gómez, S. Nevot, J. M. García, L. Echeverria

TP25 Determining the safety of baked egg home reintroduction for children with mild egg allergy

Brenda DeWitt, Judith Holloway, Donald Hodge

TP26 Demographics, investigations and patterns of sensitisation in children with oral allergy syndrome in a London Teaching Hospital

Sian Ludman, Merhdad Jafari-Mamaghani, Rosemary Ebling, Adam T. Fox, Gideon Lack, George Du Toit

TP27 Airborne peanut challenge in children: allergic reactions are rare

Sofia Lovén Björkman, Caroline Nilsson, Natalia Ballardini

TP28 The nutty question on Pediatric Wards: to be or “nut” to be?

Supriyo Basu, Jenny Hallet, Jyothi Srinivas

TP29

TP30

TP31 Allergy education in nursery schools

Hazel Stringer, Nicola Jay

TP32 Food allergy in the first year of life

Tânia Lopes, Cristina Madureira, Filipa Almeida, Susana Lopes, Paula Fonseca, Clara Vieira, Fernanda Carvalho

TP33 Prevalence and geographic distribution of oral allergy syndrome in Italian children: a multicenter study

Carla Mastrorilli, Carlo Caffarelli, Riccardo Asero, Salvatore Tripodi, Arianna Dondi, Gianpaolo Ricci, Carlotta Povesi Dascola, Elisabetta Calamelli, Francesca Cipriani, Andrea Di Rienzo Businco, Annamaria Bianchi, Paolo Candelotti, Tullio Frediani, Carmen Verga, Paolo Maria Matricardi

TP34 Are common standardised allergen extracts used in skin test enough in the diagnosis of nuts allergy?

Cristina Muñoz Archidona, Loreto González Domínguez, Ana Moreira Jorge, Sergio Quevedo Teruel, Teresa Bracamonte Bermejo, Miriam Castillo Fernández, Fernando Pineda de la Losa, Luis Ángel Echeverría Zudaire

TP35 Evaluation of IgE sensitisation in children with allergic proctocolitis and its relationship to atopic dermatitis

Despina Mermiri, Paraskevi Korovessi, Skevi Tiliakou, Evaggelia Tavoulari, Kalliopi-Maria Moraiti, Fotini Giannoula, Athina Papadopoulou

TP36 Food allergy in children: are we managing them appropriately in the Emergency Department?

Wan Jean Tee, Samir Deiratany, Raymond Seedhoo, Roisin McNamara, Ike Okafor

TP37 Importance of oil body associated allergenic proteins in nuts suspected allergy children

Loreto González Domínguez, Ana Moreira Jorge, Cristina Muñoz Archidona, Teresa Bracamonte Bermejo, Sergio Quevedo Teruel, Fernando Pineda de la Losa, Miriam Castillo Fernández, Luis Ángel Echeverría Zudaire

TP38 Practical application of basophil activation test in children with food allergy

Ekaterina Khaleva, Gennady Novic, Natalia Bychkova

THEMATIC POSTER SESSION 3: Asthma (TP39–TP57)

TP39 Effect of corticosteroid therapy upon serum magnesium level in chronic asthmatic children

Amany Abd Al-Aziz, Amany Fatouh, Ayat Motawie, Eman El Bostany, Amr Ibrahim

TP40 ADAM33 in Bulgarian children with asthma

Guergana Petrova, Dimitrinka Miteva, Snezhina Lazova, Penka Perenovska, Sylvia Andonova, Alexey Savov

TP41

TP42 The impact of vitamin D serum levels in asthma and allergic rhinitis

Maria Zoto, Marialena Kyriakakou, Paraskevi Xepapadaki, Nikolaos G. Papadopoulos

TP43 Life-threatening, first reported, paradoxical bronchospasm after nebulised Salbutamol in a 10 year old child

Paraskevi Korovessi, Mariza Vassilopoulou, Athina Balaska, Lambros Banos, Stavroula Kostaridou, Despina Mermiri

TP44

TP45 Asthma symptoms in children with treatment for allergic rhinoconjunctivitis

Jorien Wartna, Arthur M. Bohnen, Gijs Elshout, David H. J. Pols, Patrick J. E. Bindels

Erasmus MC, Rotterdam, The Netherlands

TP46 Atopy increased the risk of developing exercise-induced bronchoconstriction in young athletes

Sven F. Seys; Ellen Dilissen, Sarah Van der Eycken, An-Sofie Schelpe, Gudrun Marijsse, Thierry Troosters, Vincent Vanbelle, Sven Aertgeerts, Jan L. Ceuppens, Lieven J. Dupont, Koen Peers, Dominique M. Bullens

TP47 The effect of higher BMI on risk for asthma and treatment outcome in overweight and obese children

Ivana Banic, Sandra Bulat Lokas, Jelena Zivkovic, Boro Nogalo, Iva Mrkic Kobal, Davor Plavec, Mirjana Turkalj

TP48

TP49

TP50

TP51

TP52 The impact of a multidisciplinary project intended to change the culture of nebulisers towards pressurised metered dose inhalers

Georgeta Oliveira, Katharine Pike, Alda Melo, Tomás Amélia, José Carlos Cidrais Rodrigues, Cristina Serrano, José Manuel Lopes dos Santos, Carla Lopes

TP53

TP54

TP55

TP56 Increased asthma control in patients with severe persistent allergic asthma after 12 month of nightly temperature controlled laminar airflow (TLA)

Eckard Hamelmann, Uwe Schauer, Karl-Christian Bergmann

TP57

THEMATIC POSTER SESSION 4: Drug allergy—Dermatology (TP58–TP77)

TP58 Should we proceed directly to provocation challenges to diagnose drug allergy? Our experience says yes

Luis Moral, Teresa Toral, Nuria Marco, Beléns García Avilés, Mª Jesús Fuentes, Jesús Garde, Cristina Montahud, Javier Perona, Mª José Forniés

TP59 Anaphylaxis to 13-valent pneumococcal vaccine

Esozia Arroabarren, Marta Anda, Maria Luisa Sanz, Maria Teresa Lizaso, Candida Arregui

TP60 Intrapartum antibiotic exposure for treatment of group B streptococcus was not associated with the development of penicillin allergy in children

Sara May, Martha Hartz, Avni Joshi, Miguel A. Park

TP61 Evaluation of suspected drug hypersensitivity reactions in 169 children referred to the General Hospital

Sonja Posega Devetak, Tina Vesel, Anja Koren Jeverica, Tadej Avčin

TP62 Drug provocation testing: experience of a tertiary hospital

Leonor Castro, Carolina Gouveia, Ana Carvalho Marques, Antonio Jorge Cabral

TP63 Perioperative anaphylaxis: a growing concern in pediatric population

Luis Amaral, Fabrícia Carolino, Eunice Castro, Madalena Passos, Josefina R. Cernadas

TP64 Raising awareness of hypersensitivity to non-steroidal anti-inflammatory drugs in the pediatric age

Fabrícia Carolino, Luís Amaral, Eunice Dias de Castro, Josefina R. Cernadas

TP65 Perioperative anaphylaxis in young children: how to confirm the suspicion

Josefina R. Cernadas, Fabrícia Carolino, Luís Amaral, Fernando Pineda, Armanda Gomes

TP66 A case study of a child suspected to be penicillin allergic-digging deeper

Katherine Knight, Roisin Fitzsimons, Helen Brough

TP67 Prevalence, characteristics and risk factors of hypersensitivity reactions to antibiotics in patients with cystic fibrosis

Jobst Röhmel, Carsten Schwarz, Anne Mehl, Philippe Stock, Doris Staab

TP68 Antibiotic drug hypersensitivity in cystic fibrosis: A pilot study using cellular allergy tests for diagnostics

Jobst Röhmel, Carsten Schwarz, Christine Seib, Doris Staab, Philippe Stock

TP69 Oral antibiotics challenges in children

Anita Critchlow, Alyson Barber, Nicola Jay

TP70 Hypersensitivity reaction to vancomycin: a new successful desensitization protocol

Belen Delavalle, Teresa Garriga, Blanca Vilá, Cristina Blasco

TP71

TP72 Clinical phenotypes according to FLG gene loss of function mutations in children with atopic dermatitis

Francesca Cipriani, Annalisa Astolfi, Costanza Di Chiara, Elisabetta Calamelli, Iria Neri, Annalisa Patrizi, Gianpaolo Ricci

TP73

TP74 Urticaria in children: clinical and epidemiological features

Katerina Neskorodova, Asya Kudryavtseva

TP75

TP76 Acute urticaria at the Pediatrics Emergency Department: is it allergy?

Esozia Arroabarren, Jorge Alvarez, Marta Anda, Miriam Palacios, Marta Martinez-Merino, Ibone Vaquero

TP77

Regulatory T Cell-Dependent and -Independent Mechanisms of Immune Suppression by CD28/B7 and CD40/CD40L Costimulation Blockade

Blocking of costimulatory CD28/B7 and CD40/CD40L interactions is an experimental approach to immune suppression and tolerance induction. We previously reported that administration of a combination of CTLA-4Ig and MR1 (anti-CD40L mAb) for blockade of these interactions induces tolerance in a fully mismatched allogeneic splenocyte transfer model in mice. We now used this model to study whether regulatory T cells (Tregs) contribute to immune suppression and why both pathways have to be blocked simultaneously. Mice were injected with allogeneic splenocytes, CD4(+) T cells, or CD8(+) T cells and treated with MR1 mAb and different doses of CTLA-4Ig. The graft-versus-host reaction of CD4(+) T cells, but not of CD8(+) T cells, was inhibited by MR1. CTLA-4Ig was needed to cover CD8(+) T cells but had only a weak effect on CD4(+) T cells. Consequently, only the combination provided full protection when splenocytes were transferred. Importantly, MR1 and low-dose CTLA-4Ig treatment resulted in a relative increase in Tregs, and immune suppressive efficacy was abolished in the absence of Tregs. High-dose CTLA-4Ig treatment, in contrast, prevented Treg expansion and activity, and in combination with MR1 completely inhibited CD4(+) and CD8(+) T cell activation in a Treg-independent manner. In conclusion, MR1 and CTLA-4Ig act synergistically as they target different T cell populations. The contribution of Tregs to immune suppression by costimulation blockade depends on the concentration of CTLA-4Ig and thus on the degree of available CD28 costimulation.

Impaired barrier function in patients with house dust mite-induced allergic rhinitis is accompanied by decreased occludin and zonula occludens-1 expression

BACKGROUND

Tight junction (TJ) defects have recently been associated with asthma and chronic rhinosinusitis. The expression, function, and regulation of nasal epithelial TJs remain unknown in patients with allergic rhinitis (AR).

OBJECTIVE

We investigated the expression, function, and regulation of TJs in the nasal epithelium of patients with house dust mite (HDM)-induced AR and in an HDM-induced murine model of allergic airway disease.

METHODS

Air-liquid interface cultures of primary nasal epithelial cells of control subjects and patients with HDM-induced AR were used for measuring transepithelial resistance and passage to fluorescein isothiocyanate-dextran 4 kDa (FD4). Ex vivo transtissue resistance and FD4 permeability of nasal mucosal explants were measured. TJ expression was evaluated by using real-time quantitative PCR and immunofluorescence. In addition, the effects of IL-4, IFN-γ, and fluticasone propionate (FP) on nasal epithelial cells were investigated in vitro. An HDM murine model was used to study the effects of allergic inflammation and FP treatment on transmucosal passage of FD4 in vivo.

RESULTS

A decreased resistance in vitro and ex vivo was found in patients with HDM-induced AR, with increased FD4 permeability and reduced occludin and zonula occludens-1 expression. AR symptoms correlated inversely with resistance in patients with HDM-induced AR. In vitro IL-4 decreased transepithelial resistance and increased FD4 permeability, whereas IFN-γ had no effect. FP prevented IL-4-induced barrier dysfunction in vitro. In an HDM murine model FP prevented the allergen-induced increased mucosal permeability.

CONCLUSION

We found impaired nasal epithelial barrier function in patients with HDM-induced AR, with lower occludin and zonula occludens-1 expression. IL-4 disrupted epithelial integrity in vitro, and FP restored barrier function. Better understanding of nasal barrier regulation might lead to a better understanding and treatment of AR.

Low cord blood Foxp3/CD3γ mRNA ratios: a marker of increased risk for allergy development

BACKGROUND

Data from birth cohort studies suggest that increased cord blood total IgE and reduced cord blood regulatory T cells increase the risk of developing allergic sensitization and atopic dermatitis.

OBJECTIVE

We here addressed whether serum total IgE and hen's egg-specific IgE levels at birth and at age 1 year differed between healthy and allergic children in a Belgian birth cohort (FONIA). We furthermore studied whether these parameters as well as cord blood Foxp3/CD3γ mRNA levels might predict the allergic outcome.

METHODS AND RESULTS

Children (n = 84) were clinically assessed at the ages of 6, 12, 18, and 24 months and at 6 years. Cord blood total IgE levels above 0.35 kU/L predicted early (i.e. before or at the age of 2 years) allergy development. Presence of serum IgE antibodies to hen's egg (cut-off 0.05 Ua/mL) at the age of 1 year was associated with early as well as late (i.e. between the age of 2 and 6 years) allergy development. Cord blood Foxp3/CD3γ mRNA ratios were significantly lower in early allergic children and levels below 0.32 predicted the allergic outcome.

CONCLUSIONS AND CLINICAL RELEVANCE

Low cord blood Foxp3/CD3γ mRNA ratios are highly predictive for early allergy development, whereas specific IgE levels to hen's egg white above 0.05 Ua/mL at age 1 year predict allergy development in general.

Nasal allergen deposition leads to conjunctival mast cell degranulation in allergic rhinoconjunctivitis

BACKGROUND

The naso-ocular interaction in allergic rhinoconjunctivitis is well recognized from epidemiological, clinical, and experimental observations. The precise mechanisms remain incompletely understood. A new mouse model of allergic rhinoconjunctivitis was used to investigate the contribution of mast cells and trigeminal ganglia activation to conjunctival (conj.) inflammation after nasal allergen provocation.

METHODS

Sensitized mice were exposed to ovalbumin (OVA) via the nose and/or conjunctiva, and conj. homogenates were analyzed for histamine and substance P (using ELISA) and by eosinophil peroxidase (EPO) and beta-hexosaminidase assays. The conj. effects of nasal allergen deposition were compared with those induced by the mast cell activator C48/80 and with pretreatment of the mast cell stabilizer ketotifen or the transient receptor potential channel receptor (TRP) agonist capsaicin. Protachykinin 1 (TAC1) expression was quantified in the trigeminal ganglia using real time polymerase chain reaction.

RESULTS

At 1 hour after nasal application of OVA, increased conj. levels of beta-hexosaminidase (0.68 ± 0.03 nm versus 0.56 ± 0.02 nm; p = 0.02), histamine (751.1 ± 52.17 ng/mL versus 546.3 ± 76.91 ng/mL; p = 0.05), and EPO (0.66 ± 0.09 nm versus 0.37 ± 0.03 nm; p = 0.02) were detected compared with saline. Higher levels of TAC1 expression were found in the trigeminal ganglia at 24 hours after OVA application (1326 ± 255 versus 687.5 ± 90.77 TAC1/beta-actin; p = 0.04). Nasal challenge with C48/80 increased substance P and beta-hexosaminidase levels in the conjunctiva, as well as TAC1 expression. Pretreatment with ketotifen resulted in lower levels of substance P as well as TAC1 expression. Destruction of sensory nerves in the nose by capsaicin reduced the OVA-induced conj. levels of substance P, histamine, and beta-hexosaminidase.

CONCLUSION

Nasal allergen deposition in sensitized mice induced trigeminal TAC1 expression and conj. mast cell degranulation. These data represent a significant step forward in understanding the close interaction between nasal and conj. inflammation in allergy.

CD28/CTLA-4/B7 costimulatory pathway blockade affects regulatory T-cell function in autoimmunity

Naïve T cells require B7/CD28 costimulation in order to be fully activated. Attempts to block this pathway have been effective in preventing unwanted immune reactions. As B7 blockade might also affect Treg cells and interfere with negative signaling through membrane CTLA-4 on effector T (Teff) cells, its immune-modulatory effects are potentially more complex. Here, we used the mouse model of multiple sclerosis (MS), EAE, to study the effect of B7 blockade. An effective therapy for MS patients has to interfere with ongoing inflammation, and therefore we injected CTLA-4Ig at day 7 and 9 after immunization, when myelin-reactive T cells have been primed and start migrating toward the CNS. Surprisingly, B7 blockade exacerbated disease signs and resulted in more severe CNS inflammation and demyelination, and was associated with an enhanced production of the inflammatory cytokines IL-17 and IFN-γ. Importantly, CTLA-4Ig treatment resulted in a transient reduction of Ki67 and CTLA-4 expression and function of peripheral Treg cells. Taken together, B7 blockade at a particular stage of the autoimmune response can result in the suppression of Treg cells, leading to a more severe disease.

CD28/CTLA-4/B7 and CD40/CD40L costimulation and activation of regulatory T cells

Costimulatory signals are crucial for T cell activation. Attempts to block costimulatory pathways have been effective in preventing unwanted immune reactions. In particular, blocking the CD28/cytotoxic T lymphocyte antigen (CTLA)-4/B7 interaction (using CTLA-4Ig) and the CD40/CD40L interaction (using anti-CD40L antibodies) prevents T cell mediated autoimmune diseases, transplant rejection and graft vs host disease in experimental models. Moreover, CTLA-4Ig is in clinical use to treat rheumatoid arthritis (abatacept) and to prevent rejection of renal transplants (belatacept). Under certain experimental conditions, this treatment can even result in tolerance. Surprisingly, the underlying mechanisms of immune modulation are still not completely understood. We here discuss the evidence that costimulation blockade differentially affects effector T cells (Teff) and regulatory T cells (Treg). The latter are required to control inappropriate and unwanted immune responses, and their activity often contributes to tolerance induction and maintenance. Unfortunately, our knowledge on the costimulatory requirements of Treg cells is very limited. We therefore summarize the current understanding of the costimulatory requirements of Treg cells, and elaborate on the effect of anti-CD40L antibody and CTLA-4Ig treatment on Treg cell activity. In this context, we point out that the outcome of a treatment aiming at blocking the CD28/CTLA-4/B7 costimulatory interaction can vary with dosing, timing and underlying immunopathology.

Perioperative allergic reactions: experience in a Flemish referral centre

BACKGROUND

The incidence of perioperative anaphylactic reactions is overall estimated to be 1 per 10,000-20,000 anaesthetic procedures. We performed a retrospective analysis of patients referred to a University Allergy Centre in Belgium with the suspicion of an allergic reaction during or shortly after general anaesthesia.

OBJECTIVES

Our aim was to assess the causes of perioperative allergic reactions, to evaluate cross-reactivity among neuromuscular blocking agents (NMBA) and to analyze the diagnostic relevance of tryptase levels in the discrimination between IgE and non-IgE-mediated reactions.

METHODS

A total of 119 patients, referred from 2007 to 2011 were included. The diagnostic protocol consisted in case history, serum tryptase measurements, immunoassays and skin tests.

RESULTS

A diagnosis of IgE-mediated reaction was established in 76 cases (63.9%). The most common agents were NMBA (61.8%), antibiotics (14.5%), latex (9.2%) and chlorhexidine (5.2%). Rocuronium was the most frequently causative NMBA (48.9%). Vecuronium cross-reactivity was established by skin testing in 47.6% of cases. Cisatracurium was the NMBA most frequently tolerated (cross-reaction in 13.9%). In 23.4% of NMBA allergic patients, the reaction occurred on the first exposure. Most IgE-mediated reactions occurred during the induction phase (72.4%). Latex-induced reactions occurred mainly during maintenance and recovery phases (71.4%; p<0.02). Mean tryptase values were significantly higher in patients with IgE-mediated reactions (p=0.0001), than in those with no identified cause.

CONCLUSIONS

NMBA, antibiotics, latex and chlorhexidine were the main culprits of IgE-mediated perioperative reactions. Uncertainties remain concerning the specificity and sensitivity of skin testing. Tryptase assays can be useful in the discrimination of IgE and non-IgE-mediated reactions.

Unique gene expression and MR T2 relaxometry patterns define chronic murine dextran sodium sulphate colitis as a model for connective tissue changes in human Crohn's disease

Introduction

Chronically relapsing inflammation, tissue remodeling and fibrosis are hallmarks of inflammatory bowel diseases. The aim of this study was to investigate changes in connective tissue in a chronic murine model resulting from repeated cycles of dextran sodium sulphate (DSS) ingestion, to mimic the relapsing nature of the human disease.

Materials and Methods

C57BL/6 mice were exposed to DSS in drinking water for 1 week, followed by a recovery phase of 2 weeks. This cycle of exposure was repeated for up to 3 times (9 weeks in total). Colonic inflammation, fibrosis, extracellular matrix proteins and colonic gene expression were studied. In vivo MRI T₂ relaxometry was studied as a potential non-invasive imaging tool to evaluate bowel wall inflammation and fibrosis.

Results

Repeated cycles of DSS resulted in a relapsing and remitting disease course, which induced a chronic segmental, transmural colitis after 2 and 3 cycles of DSS with clear induction of fibrosis and remodeling of the muscular layer. Tenascin expression mirrored its expression in Crohn’s colitis. Microarray data identified a gene expression profile different in chronic colitis from that in acute colitis. Additional recovery was associated with upregulation of unique genes, in particular keratins, pointing to activation of molecular pathways for healing and repair. In vivo MRI T₂ relaxometry of the colon showed a clear shift towards higher T₂ values in the acute stage and a gradual regression of T₂ values with increasing cycles of DSS.

Conclusions

Repeated cycles of DSS exposure induce fibrosis and connective tissue changes with typical features, as occurring in Crohn’s disease. Colonic gene expression analysis revealed unique expression profiles in chronic colitis compared to acute colitis and after additional recovery, pointing to potential new targets to intervene with the induction of fibrosis. In vivo T₂ relaxometry is a promising non-invasive assessment of inflammation and fibrosis.

Interleukin-15 receptor α expression in inflammatory bowel disease patients before and after normalization of inflammation with infliximab

Interleukin-15 (IL-15) is a pro-inflammatory cytokine thought to contribute to the inflammation in inflammatory bowel diseases (IBD). The specific receptor chain IL-15Rα can be expressed as a transmembranous signalling receptor, or can be cleaved by a disintegrin and metalloprotease domain 17 (ADAM17) into a neutralizing, soluble receptor (sIL-15Rα). The aim of this study is to evaluate the expression of IL-15Rα in ulcerative colitis (UC) and Crohn's disease (CD) patients before and after infliximab (IFX) therapy. Gene expression of IL-15Rα, IL-15 and ADAM17 was measured at the mRNA level by quantitative reverse transcription-PCR in mucosal biopsies harvested before and after first IFX therapy. Concentrations of sIL-15Rα were measured in sera of patients by ELISA and IL-15Rα protein was localized in the gut by immunohistochemistry and immunofluorescence. Mucosal expression of IL-15Rα is increased in UC and CD patients compared with controls and it remains elevated after IFX therapy in both responder and non-responder patients. The concentration of sIL-15Rα in serum is also increased in UC patients when compared with controls and does not differ between responders and non-responders either before or after IFX. CD patients have levels of sIL-15Rα comparable to healthy controls before and after therapy. In mucosal tissues, IL-15Rα(+) cells closely resemble activated memory B cells with a pre-plasmablastic phenotype. To conclude, IBD patients have an increased expression of IL-15Rα mRNA in the mucosa. Expression is localized in B cells, suggesting that IL-15 regulates B-cell functions during bowel inflammation. No change in release of sIL-15Rα is observed in patients treated with IFX.

Foxp3+ regulatory T cells are activated in spite of B7-CD28 and CD40-CD40L blockade

Costimulatory signals are required for priming and activation of naive T cells, while it is less clear how they contribute to induction of regulatory T (Treg)-cell activity. We previously reported that the blockade of the B7-CD28 and CD40L-CD40 interaction efficiently suppresses allogeneic T-cell activation in vivo. This was characterized by an initial rise in Foxp3(+) cells, followed by depletion of host-reactive T cells. To further investigate effects of costimulatory blockade on Treg cells, we used an in vitro model of allogeneic CD4(+) cell activation. When CTLA-4Ig and anti-CD40L mAb (MR1) were added to the cultures, T-cell proliferation and IL-2 production were strongly reduced. However, Foxp3(+) cells proliferated and acquired suppressive activity. They suppressed activation of syngeneic CD4(+) cells much more efficiently than did freshly isolated Treg cells. CD4(+) cells activated by allogeneic cells in the presence of MR1 and CTLA-4Ig were hyporesponsive on restimulation, but their response was restored to that of naive CD4(+) cells when Foxp3(+) Treg cells were removed. We conclude that natural Treg cells are less dependent on B7-CD28 or CD40-CD40L costimulation compared with Foxp3(-) T cells. Reduced costimulation therefore alters the balance between Teff and Treg-cell activation in favor of Treg-cell activity.

Neutralization of membrane TNF, but not soluble TNF, is crucial for the treatment of experimental colitis

BACKGROUND

Agents neutralizing membrane tumor necrosis factor (mTNF) and soluble TNF (sTNF) are widely used for the treatment of inflammatory bowel disease (IBD). Neutralization of mTNF, however, is associated with increased susceptibility to infectious diseases. The aim of this study was to determine whether neutralization of sTNF exclusively, by the use of a dominant negative mutant of TNF (XENP1595), could reduce the severity of colitis in mice.

METHODS

Colitis was induced in immunodeficient mice by transfer of CD45RB(hi) CD25 T-cells. Once the disease had developed, mice were treated twice a week with XENP1595, phosphate-buffered saline (PBS), anti-TNF monoclonal antibody (mAb), or isotype control. The anti-TNF mAb blocks both mTNF and sTNF. Weights, disease activity index, macroscopic inflammation of the colon, and histological sections were evaluated. T-cell populations from the colon were analyzed by flow cytometry.

RESULTS

Treatment of mice with XENP1595 did not change the course of the disease, whereas mice treated with anti-TNF mAb recovered weight soon after the first treatment dose. Inflammation in the colon was reduced in mice treated with anti-TNF mAb compared to isotype control-treated animals. Mice treated with XENP1595 had a similar degree of inflammation in the colon as PBS-treated animals. The number of effector and regulatory T-cells in the colon remained unaffected by all treatments.

CONCLUSIONS

Neutralization of sTNF exclusively was unable to induce remission in T-cell-mediated colitis, suggesting that neutralization of mTNF is crucial for the treatment of IBD.

Explorative study on patient's perceived knowledge level, expectations, preferences and fear of side effects for treatment for allergic rhinitis

Background

In spite of the high prevalence of allergic rhinitis (AR) and the evidence-based guidelines for treatment, little is known about the patients’ perceived knowledge level, expectations, preferences for treatment, and fear for side effects of treatment for AR. This study aimed at gaining insight into these patient-related factors.

Methods

This explorative cross-sectional survey study included a convenience sample of 170 patients with rhinitis and clinical suspicion of allergy at the department of Otorhinolaryngology and Allergology. Patients’ perceived knowledge level, expectations, patient preferences, and fear of side effects of allergy treatment were collected via a self-report questionnaire developed for the purpose of this study.

Results

22% of all patients (38/170) reported to have knowledge about anti-allergic treatment. 40% (55/170) of rhinitis patients expected to be cured by the prescribed treatment, whereas 43% (73/170) of patients expected suppression of allergic symptoms. Nasal spray was the preferred route of anti-allergic drug administration in 30% (52/170) of patients, followed by oral treatment (24%; 42/170), combination therapy (16%; 30/170), and injection therapy (15%; 27/170). More patients would choose a combination treatment with step-down approach (31%; 53/170) than mono-therapy with a step-up approach (20%; 34/170). Fear for side effects was reported mainly for nasal corticosteroids (48%; 81/170) and less for oral antihistamines (33%; 36/170), leucotriene antagonists (21%, 36/170) and immunotherapy (19%, 33/170).

Conclusions

Patients consulting for rhinitis have high expectations of anti-allergic treatment, prefer a nasal spray above oral treatment, prefer combined treatment rather than monotherapy, and fear adverse events of anti-allergic treatment.

Effects of haptoglobin polymorphisms and deficiency on susceptibility to inflammatory bowel disease and on severity of murine colitis

BACKGROUND

Haptoglobin (Hp) is a haemoglobin-binding protein with immunomodulatory properties. Its gene (16q22) harbours a common polymorphism with two different alleles: Hp1 and Hp2. Genotype Hp22 has been shown to be over-represented in different immune diseases. Results in Crohn's disease (CD) are contradictory.

AIMS

To determine whether Hp plays a role in inflammatory bowel disease, both genetically and functionally.

METHODS

1061 patients with CD, 755 with ulcerative colitis (UC) and 152 with primary sclerosing cholangitis, as well as 452 healthy controls, were genotyped using touch-down PCR. To confirm association results, 464 CD trios and 151 UC trios were genotyped. Serum Hp concentrations were determined in 62 individuals of different genotype. Colitis was induced in mice with dextran sulphate sodium (DSS) and oxazolone (Oxa). Cytokine production was evaluated by mRNA quantification in colonic tissue and ELISA on supernatants of mesenteric lymph node cells.

RESULTS

Prevalence of Hp2 was higher in CD and UC than in controls. In the confirmatory cohorts, Hp2 was over-transmitted to the affected offspring. Serum Hp concentrations were higher in individuals with genotypes Hp11 and Hp21 than in those with Hp22 (1.38 vs 0.89 g/l). DSS- and Oxa-induced colitis were more severe in Hp-deficient mice than in control mice and accompanied by higher concentrations (although not statistically significantly different) of tissue mRNA for cytokines. Interleukin-17 production was significantly higher in the presence of Hp-deficient serum compared with wild-type serum.

CONCLUSIONS

The Hp gene may play a role in susceptibility to inflammatory bowel disease. Its implication in other immune diseases underscores the common pathways between these diseases. Experimental models of colitis showed that Hp has a protective role in inflammatory colitis, most likely by inhibiting the production of Th1 and Th17 cytokines.

Placental growth factor contributes to bronchial neutrophilic inflammation and edema in allergic asthma

Placental growth factor (PlGF) and its receptor vascular endothelial growth factor receptor 1 (VEGFR1) play an important role in pathological conditions related to angiogenesis, vascular leakage, and inflammation. This study investigated their contributions to inflammation and the formation of edema in allergic asthma. The expression of PlGF and VEGFR1 was measured in induced sputum of patients with asthma (n = 11) and healthy subjects (n = 11), and in bronchial biopsies of house dust mite (HDM)-allergic patients stimulated with HDM allergens. The effects of the endonasal administration of human PlGF-2 and PlGF deficiency on inflammation and edema were evaluated in a murine model of allergic asthma. The migration of human neutrophils in response to hPlGF-2 was tested in vitro. The expression of PlGF and VEGFR1 was significantly higher in the sputum of patients with asthma, and in Der p 1-induced PlGF in biopsies from HDM-allergic patients. PlGF was increased in the bronchi of ovalbumin (OVA)-challenged mice compared with control mice (65 ± 17 pg/mg versus 18 ± 1 pg/mg, respectively; P < 0.01), and VEGFR1 was expressed in bronchial epithelium, endothelium (control mice), and inflammatory cells (OVA-challenged mice). The endonasal instillation of hPlGF-2 in wild-type, OVA-challenged mice led to an increase in bronchial neutrophils, lung tissue wet/dry ratio, and IL-17. PlGF-deficient mice showed lower numbers of BAL-infiltrating neutrophils, a reduced lung wet/dry ratio, and lower production of IL-17, macrophage inflammatory protein-2, and granulocyte chemotactic protein-2/LPS-induced chemokine compared with wild-type, OVA-challenged mice. hPlGF-2 induced the migration of human neutrophils in vitro in a VEGFR1-dependent way. PlGF and its receptor VEGFR1 are up-regulated in allergic asthma and play a proinflammatory role by inducing tissue edema, and increasing tissue neutrophilia and the production of IL-17.

Blocking costimulatory pathways: prospects for inducing transplantation tolerance

Tolerance induction to alloantigens is a major challenge in transplant immunology. Whereas conventional immunosuppression inhibits the immune system in a nonspecific way, thereby also undermining an appropriate immune response towards potentially harmful infectious organisms, tolerance in a transplantation setting is restricted to alloantigens, while protective immunity is preserved. Moreover, tolerance implies an immunological status that is preserved after withdrawal of the tolerance-inducing therapy. Among the most promising strategies to induce immunological tolerance are costimulation blockade and establishment of mixed chimerism. Despite significant advances, we still know little about the mechanisms responsible for such tolerance. In this article, we discuss tolerance induction to transplantation antigens by costimulation blockade.

Conjunctival effects of a selective nasal pollen provocation

BACKGROUND

Several clinical and experimental observations suggest that allergen deposition in the nose may partially be responsible for the induction of conjunctival symptoms in allergic rhinitis. The aims of this study were to evaluate the induction of conjunctival symptoms by selective nasal allergen provocation and to assess the feasibility of the different tools for evaluation of conjunctival allergic inflammation.

METHODS

Grass pollen allergic subjects with rhinoconjunctivitis symptoms during the pollen season (n = 12) underwent a nasal sham and grass pollen provocation extra-seasonally. Nasal and conjunctival symptoms were scored using the Visual Analogue Scale (VAS) system at baseline, 15 min, 1 h and 24 h after provocation. In addition to Peak Nasal Inspiratory flow (PNIF) measurements, conjunctival inflammation and vascular congestion were evaluated and histamine and substance P levels in tear fluid were measured.

RESULTS

Selective nasal grass pollen provocation induced ocular pruritus, lacrimation and conjunctival vascular congestion. PNIF values correlated inversely with lacrimation (r = -0.71, P < 0.001) and ocular pruritus (r = -0.41, P < 0.05). Four out of 11 patients showed a conjunctival eosinophilic inflammation and levels of histamine (r = 0.73, P < 0.05) and substance P (r = 0.67, P = 0.05) in tear fluid correlated with conjunctival symptoms.

CONCLUSION

Selective nasal grass pollen provocation induced conjunctival inflammation, ocular pruritus and lacrimation, which correlated with histamine and substance P levels in tear fluid and inversely with the PNIF values. These data show a naso-ocular interaction in allergic rhinitis and offer objective tools for evaluation of conjunctival inflammation in allergic rhinoconjunctivitis.

Impact of lipoteichoic acid modification on the performance of the probiotic Lactobacillus rhamnosus GG in experimental colitis

While some probiotic strains might have adjuvant effects in the therapy for inflammatory bowel diseases (IBD), these effects remain controversial and cannot be generalized. In this study, a dltD mutant of the model probiotic Lactobacillus rhamnosus GG (LGG), having a drastic modification in its lipoteichoic acid (LTA) molecules, was analysed for its effects in an experimental colitis model. Dextran sulphate sodium (DSS) was used to induce either moderate to severe or mild chronic colitis in mice. Mice received either phosphate-buffered saline (PBS), LGG wild-type or the dltD mutant via the drinking water. Macroscopic parameters, histological abnormalities, cytokine and Toll-like receptor (TLR) expression were analysed to assess disease activity. LGG wild-type did not show efficacy in the different experimental colitis set-ups. This wild-type strain even seemed to exacerbate the severity of colitic parameters in the moderate to severe colitis model compared to untreated mice. In contrast, mice treated with the dltD mutant showed an improvement of some colitic parameters compared to LGG wild-type-treated mice in both experimental models. In addition, treatment with the dltD mutant correlated with a significant down-regulation of Toll-like receptor-2 expression and of downstream proinflammatory cytokine expression in the colitic mice. These results show that molecular cell surface characteristics of probiotics are crucial when probiotics are considered for use as supporting therapy in IBD.

Staphylococcus aureus enterotoxin B augments granulocyte migration and survival via airway epithelial cell activation

BACKGROUND

Staphylococcus aureus enterotoxin B (SEB) has recently been postulated to be involved in the pathology of granulocyte-dominated disease. Studying the immunologic interaction between SEB and airway epithelial cells in immortalized cell lines or long-term epithelial cell cultures has obvious disadvantages.

METHODS

We used a novel technique of freshly isolated and purified human nasal epithelial cells (HNEC) from healthy, nonallergic individuals, which were incubated for 24 h without/with SEB at different concentrations. Chemokine production was evaluated in the supernatant using Cytometric Bead Array. The chemotactic activity of the supernatant was studied in vitro using a Boyden chamber. Survival was evaluated with flow cytometry, using propidium iodide to identify dead cells.

RESULTS

Staphylococcus aureus enterotoxin B showed a dose-dependent induction of interferon-inducible protein-10, monokine induced by interferon-gamma, regulated upon activation normal T cell expressed and secreted, monocyte chemoattractant protein 1 (MCP-1) and granulocyte colony stimulating factor production by epithelial cells in vitro. The supernatant of epithelial cells had chemotactic activity for granulocytes in vitro, which was enhanced in the supernatant of SEB-stimulated epithelial cells. Reduced number of propidium iodide positive granulocytes was found in the conditions where supernatant of SEB-stimulated epithelial cells was applied.

CONCLUSION

Staphylococcus aureus enterotoxin B exerts a direct pro-inflammatory effect on HNEC, with induction of chemokine and growth factor release, resulting in the migration and prolonged survival of granulocytes in vitro.

Reciprocal changes of Foxp3 expression in blood and intestinal mucosa in IBD patients responding to infliximab

BACKGROUND

Immune therapies may act in inflammatory bowel diseases (IBD) by modulating regulatory T cells (Tregs). Therefore, we investigated the effect of infliximab (IFX) therapy on Forkhead box protein3 (Foxp3) T cells in blood and intestinal mucosa from Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

Forty patients with active IBD (23 CD / 17 UC) were treated with IFX 5 mg/kg intravenously at weeks 0, 2, 6, and each 8 weeks thereafter. Blood samples were obtained before every infusion and T-lymphocyte subsets were characterized by flow cytometry. Foxp3 expression in intestinal biopsies from 43 patients with active IBD (19 CD / 24 UC) before and after IFX infusion and from 6 controls were assessed by quantitative reverse-transcription polymerase chain reaction and immunohistochemistry. Plasma C-reactive protein (CRP), clinical response, and endoscopic healing data were collected in parallel.

RESULTS

IFX therapy resulted in a significant and sustained relative increase of CD4(+)CD25(+)Foxp3(+) Treg and of CD4(+)CD25(-)Foxp3(+) Treg cells in peripheral blood (both P < 0.0001 compared to baseline), particularly in responders (both P < 0.05 compared to nonresponders). The change in CRP over time inversely correlated with the increase of CD25(+)Foxp3(+) cells (P < 0.001, r = -0.39) and durable clinical response was associated with a sustained increase of circulating Foxp3(+) cells. Surprisingly, IFX therapy downregulated mucosal mRNA and protein expression of Foxp3 in UC and CD responders (both P < 0.001) but not in nonresponders.

CONCLUSIONS

IFX therapy has opposite effects in Foxp3(+) Treg cells in blood and gut mucosa, which suggests a redistribution of this important T-cell subset.

Effects of T cell-induced colonic inflammation on epithelial barrier function

BACKGROUND

Epithelial barrier disturbance is thought to contribute to the pathogenesis of inflammatory bowel diseases; however, it remains unclear whether it is a primary defect participating to the onset of inflammation or only a consequence of sustained inflammation.

METHODS

A time course study of epithelial barrier functions and immune mediators was performed in the CD4(+)CD45RB(hi) T cell transfer model of colitis using Ussing chambers.

RESULTS

In nonreconstituted severe combined immunodeficiency (SCID) mice, no epithelial dysfunction was observed. However, after transfer of CD4(+)CD45RB(hi) T cells or total CD4(+) T cells, colon of SCID mice displayed a decreased epithelial resistance, even before overt microscopic inflammation had occurred. Sustained colitis of CD4(+)CD45RB(hi) T cell reconstituted mice was also associated with enhanced subepithelial resistance, enhanced paracellular permeability, and decreased net ion transport. All these reflect a disturbance of barrier function and may contribute to diarrhea. Epithelial resistance was positively correlated with interleukin 10 (IL-10) and transforming growth factor beta (TGF-beta) levels and net ion transport inversely correlated with tumor necrosis factor alpha (TNF-alpha) levels, pointing to the protective effect of IL-10 and TGF-beta and to a damaging effect of TNF-alpha. Indomethacin, a nonselective COX inhibitor, decreased epithelial resistance independent of T cells and inflammation, but its effect was more pronounced in inflamed colon.

CONCLUSIONS

Induction of colitis by transfer of CD4(+)CD45RB(hi) T cells in SCID mice leads to changes in the colonic epithelium before colitis develops. Decreased epithelium resistance might contribute to the development of colitis; however, it is not sufficient to lead to chronic inflammation.

Selective nasal allergen provocation induces substance P-mediated bronchial hyperresponsiveness

Although the concept of "global airway allergy" has become widely accepted during recent years, nasobronchial interaction and its mechanisms remain incompletely understood. The experimental study of the effect of nasal allergen deposition on lower airway pathology is hampered by the difficulty of avoiding lower airway penetration of the allergens. In ovalbumin-sensitized mice with experimental airway allergy, nasal allergen provocations were performed after complete anatomical separation of upper and lower airways by means of a tracheotomy. A canula was inserted in the trachea, and the trachea was ligated, thus inhibiting any passage of allergens from upper to lower airways. Mice showed bronchial hyperresponsiveness to methacholine as early as 4 hours after nasal allergen provocation in the absence of recruitment of inflammatory cells. An increased substance P (SP) concentration in the bronchial lumen was found, as well as an increased number of SP-positive pulmonary nerves. Treatment with a neurokinin (NK) 1 receptor antagonist abolished the allergen-induced bronchial hyperresponsiveness. Moreover, endobronchial administration of SP caused NK1 receptor-dependent bronchial hyperresponsiveness in mice with airway allergy. Nasal allergen provocation rapidly induces bronchial hyperresponsiveness via pulmonary up-regulation of SP and activation of NK1 receptors.

Staphylococcus aureus enterotoxin B facilitates allergic sensitization in experimental asthma

BACKGROUND

Staphylococcus aureus Enterotoxin B (SEB) has immunomodulatory effects in allergic airway disease. The potential contribution of SEB to the sensitization process to allergens remains obscure.

OBJECTIVE

In order to study the effects of staphylococcal-derived toxins on the sensitization to ovalbumin (OVA) and induction of allergic airway inflammation, we have combined the nasal application of OVA with different toxins.

METHODS

Nasal applications of OVA and saline, SEA, SEB, toxic shock syndrome toxin (TSST)-1, protein A or lipopolysaccharide (LPS) were performed on alternate days from day 0 till 12. On day 14, mice were killed for the evaluation of OVA-specific IgE, cytokine production by mediastinal lymph node (MLN) cells and bronchial hyperreactivity (BHR) to inhaled metacholine. The effect of SEB on dendritic cell (DC) migration and maturation, and on T cell proliferation was evaluated.

RESULTS

Concomitant endonasal application of OVA and SEB resulted in OVA-specific IgE production, whereas this was not found with SEA, TSST-1, protein A, LPS or OVA alone. Increased DC maturation and migration to the draining lymph nodes were observed in OVA/SEB mice, as well as an increased T cell proliferation. Bronchial inflammation with an influx of eosinophils and lymphocytes was demonstrated in OVA/SEB mice, together with hyperresponsiveness and the production of IL-4, IL-5, IL-10 and IL-13 by MLN stimulated with OVA.

CONCLUSIONS

Our data demonstrate that SEB facilitates sensitization to OVA and consecutive bronchial inflammation with features of allergic asthma. This is likely due to augmentation of DC migration and maturation, as well as the allergen-specific T cell proliferation upon concomitant OVA and SEB application.

Sensitization to inhaled ryegrass pollen by collateral priming in a murine model of allergic respiratory disease

BACKGROUND

Mouse models of asthma suffer from the necessity to prime the animals by injections before respiratory exposure. Our aim was to develop a mouse model that mimics the progression of human allergic disease upon low-dose inhaled allergen exposure.

METHODS

Mice were primed intraperitoneally to ovalbumin (OVA) before they were exposed repeatedly to aerosols of either OVA, ryegrass (Lolium perenne) pollen extract, or both concomitantly. The sensitization to ryegrass pollen proteins was evaluated by measurement of specific serum antibody, by the respiratory response to a challenge with ryegrass pollen extract and by lung cytokine production after challenge.

RESULTS

Inhalation of ryegrass pollen extract alone did not result in sensitization. Sensitization to inhaled ryegrass pollen proteins, however, did occur in mice that had been sensitized to OVA by intraperitoneal injections and were then exposed to inhaled ryegrass pollen extract and OVA simultaneously. T and B cell priming was ascertained by ryegrass pollen-specific IgG1 and IgE antibody production and by induction of airway inflammation and of Th2 cytokine mRNA transcripts in the lungs upon airway challenge with ryegrass pollen extract. A progressive spread of the IgE/IgG1 response to different ryegrass pollen proteins could be visualized in immunoblots by comparing antibody patterns at day 56 and 86.

CONCLUSIONS

Low-dose inhalatory allergen exposure results in sensitization when airways are exposed at the same time to another allergen to which the animals are already sensitized. This model can help to unravel the mechanisms that underlie the development and progression of respiratory allergic diseases.

Haptoglobin deficiency facilitates the development of autoimmune inflammation

Haptoglobin (HP) is an acute phase protein synthesized by liver cells in response to IL-6. HP has been demonstrated to modulate the immune response and to have anti-inflammatory activities. To analyze HP's effect on autoimmune inflammation, we here studied the course of EAE induced by immunization of Hp knockout (Hp(-/-)) and syngeneic WT mice with myelin oligodendrocyte glycoprotein peptide (MOG(35-55)). Hp(-/-)mice suffered from a more severe disease that was associated with increased expression of IL-17A, IL-6, and IFN-gamma mRNA in the CNS and with a denser cellular infiltrate in the spinal cord. During the recovery phase, a significantly higher number of myeloid DC, CD8+ cells, IL-17+ CD4+ and IFN-gamma+ CD4+ cells persisted in the CNS of Hp(-/-) mice. Absence of HP affected the priming and differentiation of T cells after MOG(35-55) immunization, as levels of Th2 cytokines produced in response to MOG stimulation by Hp(-/-) T cells were reduced. These results suggest that HP plays a modulatory and protective role on autoimmune inflammation of the CNS.

Immune dysfunction in patients with functional gastrointestinal disorders

There is increasing evidence for involvement of the immune system in functional gastrointestinal disorder (FGID), including onset after acute gastrointestinal infections, genotypes resulting in altered cytokine expression and abnormal presence of immune cells. Our aim was to assess cellular and humoral immune responses in (i) FGIDs, compared to healthy subjects and (ii) acute vs unspecified onset FGIDs. Lymphocytic [interleukin (IL)-5, IL-10, IL-13 and interferon gamma (IFN-gamma)] and monocytic [IL-10, IL-12, tumour necrosis factor (TNF)-alpha] cytokine production was characterized at baseline and after stimulation with phytohemagglutinine and anti-CD28 or lipopolysaccharide (LPS) in controls (n = 32), irritable bowel syndrome (IBS) (n = 30), functional dyspepsia (FD) (n = 23) and non-cardiac chest pain (NCCP) (n = 15). Serum IL-6 and IL-10 concentrations were compared, and the immunophenotype was assessed using fluorescent-activated cell sorter. Findings were compared for acute vs unspecified onset FGID. Compared to controls, stimulated lymphocyte expression of IL-5 and IL-13 was enhanced in IBS, FD and NCCP (all P < 0.05). Conversely, the stimulated monocytic IL-12 and lymphocytic IL-10 expression were reduced in IBS and FD, while IFN-gamma expression was also reduced in FD patients. Except for an increase in the numbers of CD3(+)CD45RA(+)CD45RO(+) cells, no distinct cellular profile was detected. Patients with a presumed acute onset of their symptoms had higher serum IL-10 levels and more CD3(+)CD45RA(+)CD45RO(+) cells, while TNF-alpha levels following stimulation with LPS were higher in FD patients reporting an acute onset. A shift towards a Th2 cytokine profile is present in FGID, while the cellular immunophenotype remains largely unchanged. Further research is indicated and could provide new therapeutic strategies for these disorders.

DC vaccination with anti-CD25 treatment leads to long-term immunity against experimental glioma

We studied the feasibility, efficacy, and mechanisms of dendritic cell (DC) immunotherapy against murine malignant glioma in the experimental GL261 intracranial (IC) tumor model. When administered prophylactically, mature DCs (DCm) ex vivo loaded with GL261 RNA (DCm-GL261-RNA) protected half of the vaccinated mice against IC glioma, whereas treatment with mock-loaded DCm or DCm loaded with irrelevant antigens did not result in tumor protection. In DCm-GL261-RNA-vaccinated mice, a tumor-specific cellular immune response was observed ex vivo in the spleen and tumordraining lymph node cells. Specificity was also shown in vivo on the level of tumor challenge. Depletion of CD8(+) T-cells by anti-CD8 treatment at the time of tumor challenge demonstrated their essential role in vaccine-mediated antitumor immunity. Depletion of CD25(+) regulatory T-cells (Tregs) by anti-CD25 (aCD25) treatment strongly enhanced the efficacy of DC vaccination and was itself also protective, independently of DC vaccination. However, DC vaccination was essential to protect the animals from IC tumor rechallenge. No long-term protection was observed in animals that initially received aCD25 treatment only. In mice that received DC and/or aCD25 treatment, we retrieved tumor-specific brain-infiltrating cytotoxic T-lymphocytes. These data clearly demonstrate the effectiveness of DC vaccination for the induction of long-lasting immunological protection against IC glioma. They also show the beneficial effect of Treg depletion in this kind of glioma immunotherapy, even combined with DC vaccination.