An optimized, robust and reproducible protocol to generate well-differentiated primary nasal epithelial models from extremely premature infants

Extremely premature infants are prone to severe respiratory infections, and the mechanisms underlying this exceptional susceptibility are largely unknown. Nasal epithelial cells (NEC) represent the first-line of defense and adult-derived ALI cell culture models show promising results in mimicking in vivo physiology. Therefore, the aim of this study was to develop a robust and reliable protocol for generating well-differentiated cell culture models from NECs of extremely premature infants. Nasal brushing was performed in 13 extremely premature infants at term corrected age and in 11 healthy adult controls to obtain NECs for differentiation at air-liquid interface (ALI). Differentiation was verified using imaging and functional analysis. Successful isolation and differentiation was achieved for 5 (38.5%) preterm and 5 (45.5%) adult samples. Preterm and adult ALI-cultures both showed well-differentiated morphology and ciliary function, however, preterm cultures required significantly longer cultivation times for acquiring full differentiation (44 +/- 3.92 vs. 23 +/- 1.83 days; p <0.0001). Moreover, we observed that recent respiratory support may impair successful NECs isolation. Herewithin, we describe a safe, reliable and reproducible method to generate well-differentiated ALI-models from NECs of extremely premature infants. These models provide a valuable foundation for further studies regarding immunological and inflammatory responses and respiratory disorders in extremely premature infants.Peer reviewe

High-throughput sequencing enhanced phage display enables the identification of patient-specific epitope motifs in serum

Phage display is a prominent screening technique with a multitude of applications including therapeutic antibody development and mapping of antigen epitopes. In this study, phages were selected based on their interaction with patient serum and exhaustively characterised by high-throughput sequencing. A bioinformatics approach was developed in order to identify peptide motifs of interest based on clustering and contrasting to control samples. Comparison of patient and control samples confirmed a major issue in phage display, namely the selection of unspecific peptides. The potential of the bioinformatic approach was demonstrated by identifying epitopes of a prominent peanut allergen, Ara h 1, in sera from patients with severe peanut allergy. The identified epitopes were confirmed by high-density peptide micro-arrays. The present study demonstrates that high-throughput sequencing can empower phage display by (i) enabling the analysis of complex biological samples, (ii) circumventing the traditional laborious picking and functional testing of individual phage clones and (iii) reducing the number of selection rounds.Fil: Christiansen, Anders. Technical University of Denmark; DinamarcaFil: Kringelum, Jens V.. Technical University of Denmark; DinamarcaFil: Hansen, Christian S.. Technical University of Denmark; DinamarcaFil: Bøgh, Katrine L.. Technical University of Denmark; DinamarcaFil: Sullivan, Eric. Roche Nimble Gen; Estados UnidosFil: Patel, Jigar. Roche Nimble Gen; Estados UnidosFil: Rigby, Neil M.. Institute of Food Research; Reino UnidoFil: Eiwegger, Thomas. Medical University of Vienna; AustriaFil: Szépfalusi, Zsolt. Medical University of Vienna; AustriaFil: Masi, Federico De. Technical University of Denmark; DinamarcaFil: Nielsen, Morten. Technical University of Denmark; Dinamarca. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: Lund, Ole. Technical University of Denmark; DinamarcaFil: Dufva, Martin. Technical University of Denmark; Dinamarc

Peanut‐induced anaphylaxis in children and adolescents: Data from the European Anaphylaxis Registry

Background Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%-1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents. Methods Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre. Results 3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004). Conclusions The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition

Subsequent MRI of pediatric patients after an adverse reaction to Gadolinium-based contrast agents.

BACKGROUND:Gadolinium-based contrast agent (GBCA)-enhanced magnetic resonance imaging (MRI) scans often must be used repeatedly in pediatric oncologic patients. Although GBCAs are usually well tolerated, severe and life-threatening allergic reactions might occur, which can result in overly cautions adherence to special precautions in patients. PURPOSE:To evaluate the management of the reported GBCA-associated adverse reactions in subsequent contrast-enhanced MRIs in pediatric patients, distinguishing non-allergic and allergic reactions. MATERIALS AND METHODS:In this retrospective, cross-sectional study, consecutive pediatric neurooncological patients who underwent GBCA-enhanced MRI at our university hospital, between 2007 and 2016, were eligible. The patients' history was evaluated with regard to any adverse events after GBCA administration. In a subset of patients with reported adverse reactions, the institutional premedication regime or an allergy work-up in clinical practice were performed, using either skin-prick tests or intravenous provocation tests in a double-blind procedure. RESULTS:Included were 8156 contrast-enhanced MRI scans in 2109 patients. Nineteen acute adverse events (19/8156; 0.23%) in 17 patients (17/2109; 0.81%) were reported. Despite a premedication regime in 14 patients, three patients (3/14; 21.4%) reported a breakthrough reaction. None of the 12 patients who underwent skin-prick tests or intravenous provocation tests showed allergic reactions. At least one well-tolerated GBCA was identified in almost every tested patient. CONCLUSION:A fast-track allergy work-up can help to distinguish non-allergic and allergic reactions and to identify a well-tolerated GBCA, thus avoiding unnecessary premedication for subsequent GBCA administrations

Effects of chemical mediators of anaphylaxis on ciliary function

We assessed the effects of selected chemical mediators of anaphylaxis on CBF in vitro. Ciliated epithelial cells were obtained from the trachea of conscious sheep with a cytology brush and suspended in a perfusion chamber containing KH. Ciliary activity was viewed microscopically and recorded on videotape for subsequent slow-motion analysis of CBF. Prostaglandin E 1 (10 −8M to 10 −6M), prostaglandin E 2 (10 −10M to 10 −6M), and leukotriene-C 4 (10 −8M) increased CBF between 7% and 33%. Histamine caused ciliostimulation only at the relatively high concentrations above 10 −5M (7% increase in CBF), whereas prostaglandin F 2α (10 −10M and 10 −6M) was without effect. In no preparation was ciliary discoordination observed. These findings indicate that several chemical mediators of anaphylaxis stimulate CBF and that the previously described impairment of mucociliary transport in stable allergic asthma or antigen-induced bronchoconstriction is probably not caused by a primary alteration of ciliary function

White Paper on Peanut Allergy - Part 4: Management and Therapy for Patients with Peanut Allergy

Bluemchen K, Fischl A, Eiwegger T, et al. White Paper Erdnussallergie - Teil 4: Management und Therapie der Erdnussallergie. Allergo Journal. 2022;31(3):34-55.Das bisherige Management einer IgE-vermittelten primären Erdnussallergie besteht aus den beiden Grundsäulen "Expositionsprophylaxe" mit Meidung des Allergens sowie "Notfalltherapie" mit kurzfristiger Behandlung einer akuten allergischen Reaktion nach akzidenteller Ingestion. Akzidentelle Reaktionen sind trotz versuchter Meidung häufig. Der Schweregrad einer allergischen oder auch anaphylaktischen Reaktion nach akzidentellem Genuss ist zuvor schwer abschätzbar. Zudem können Reaktionsschwellen je nach begleitendem Augmentationsfaktor schwanken. Daher sollte jeder Erdnussallergiker eine individuelle Ernährungsberatung sowie eine Einweisung in das Notfallset und gegebenenfalls eine Anaphylaxieschulung erhalten. Seit Herbst 2021 steht mit einem Medikament zur oralen Immuntherapie (OIT) nun erstmals eine kausale Behandlungsmöglichkeit für vier- bis 17-jährige erdnussallergische Kinder und Jugendliche zur Verfügung. Die OIT mit Erdnussprotein als entfettetes Pulver von Arachis hypogaea, semen (Erdnüsse) führt zu einer Desensibilisierung mit einer guten Wirksamkeit und einem akzeptablen Sicherheitsprofil. Weitere Behandlungsoptionen mit unterschiedlichen Therapieansätzen befinden sich ebenfalls in der Entwicklung und werden in den kommenden Jahren wahrscheinlich das Therapieangebot erweitern

Position paper of the Food Allergy Working Group of the German Society for Allergology and Clinical Immunology (Deutsche Gesellschaft für Allergologie und klinische Immunologie, DGAKI)

Background: Parents of school-age children with food allergies and potential anaphylactic reactions want their children to have an unburdened and risk-free everyday school life. Thus, particularly in the case of peanut allergy, demands for peanut-free schools are put forward. Results and discussion: The position paper of the food allergy working group of the German Society for Allergology and Clinical Immunology (Deutsche Gesellschaft für Allergologie und klinische Immunologie) highlights why the concept of peanut-free schools does not protect peanut allergic children, but rather bears potential disadvantages and risks for all those involved. The focus on peanut as a potential trigger of anaphylactic reactions ignores other relevant triggers. Conclusion: In order to address the fears and concerns of patients, parents, and school staff, it is mandatory to develop various coping strategies. These should enable and ensure the safety and participation of food-allergic pupils in classes and other school activities. Therefore, it is important to implement adequate measures for allergen avoidance and emergency treatment for students with confirmed food allergies