While both the incidence and general awareness of food allergies is increasing, the variety and clinical availability of therapeutics remain limited. Therefore, investigations into the potential factors contributing to the development of food allergy and the mechanisms of natural tolerance or induced desensitization are required. In addition, a detailed understanding of the pathophysiology of food allergies is needed to generate compelling, enduring, and safe treatment options. New findings regarding the contribution of barrier function, the effect of emollient interventions, mechanisms of allergen recognition, and the contributions of specific immune cell subsets through rodent models and human clinical studies provide novel insights. With the first approved treatment for peanut allergy, the clinical management of food allergy is evolving towards less intensive, alternative approaches involving fixed doses, lower maintenance dose targets, co-administration of biologicals, adjuvants, and tolerance-inducing formulations. The ultimate goal is to improve immunotherapy and develop precision-based medicine via risk phenotyping allowing optimal treatment for each food-allergic patient.

A document by Carmen H. Li. Click on the document to view its contents.

Multisystem inflammatory syndrome in children (MIS-C) is a rare, but severe complication of coronavirus disease 2019 (COVID-19). It develops approximately four weeks after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and involves hyperinflammation with multisystem injury, commonly progressing to shock. The exact pathomechanism of MIS-C is not known, but immunological dysregulation leading to cytokine storm plays a central role. In response to the emergence of MIS-C, the European Academy of Allergy and Clinical Immunology (EAACI) established a task force (TF) within the Immunology Section in May 2021. With the use of an online Delphi process, TF formulated clinical statements regarding immunological background of MIS-C, diagnosis, treatment, follow-up, and the role of COVID-19 vaccinations. MIS-C case definition is broad, and diagnosis is made based on clinical presentation. The immunological mechanism leading to MIS-C is unclear and depends on activating multiple pathways leading to hyperinflammation. Current management of MIS-C relies on supportive care in combination with immunosuppressive and/or immunomodulatory agents. The most frequently used agents are systemic steroids and intravenous immunoglobulin. Despite good overall short-term outcome, MIS-C patients should be followed-up at regular intervals after discharge, focusing on cardiac disease, organ damage, and inflammatory activity. COVID-19 vaccination is a safe and effective measure to prevent MIS-C. In anticipation of further research, we propose a convenient and clinically practical algorithm for managing MIS-C developed by the Immunology Section of the EAACI.

Background: Food allergy affects up to 8% of the pediatric population. Despite ongoing efforts, treatment options remain limited. Novel models of food allergy are needed to study response patterns downstream of IgE-crosslinking and evaluate drugs modifying acute events. Here, we report a novel human ex vivo model that displays acute, allergen-specific, IgE-mediated smooth muscle contractions using precision cut intestinal slices (PCIS). Methods: PCIS were generated using gut tissue samples from children who underwent clinically indicated surgery. Viability and metabolic activity were assessed from 0-24h. Distribution of relevant cell subsets was confirmed using single cell nuclear sequencing. PCIS were passively sensitized using plasma from peanut allergic donors or peanut-sensitized non-allergic donors, and exposed to various stimuli including serotonin, histamine, FcɛRI-crosslinker and food allergens. Smooth muscle contractions and mediator release functioned as readouts. A novel program designed to measure contractions was developed to quantify responses. The ability to demonstrate the impact of antihistamines and immunomodulation from peanut oral immunotherapy (OIT) was assessed. Results: PCIS viability was maintained for 24h. Cellular distribution confirmed the presence of key cell subsets including mast cells. The video analysis tool reliably quantified responses to different stimulatory conditions. Smooth muscle contractions were allergen-specific and reflected the clinical phenotype of the plasma donor. Tryptase measurement confirmed IgE-dependent mast cell-derived mediator release. Antihistamines suppressed histamine-induced contraction and plasma from successful peanut OIT suppressed peanut-specific PCIS contraction. Conclusion: PCIS represent a novel human tissue-based model to study acute, IgE-mediated food allergy and pharmaceutical impacts on allergic responses in the gut.

Article Type : Letter to the EditorTitle : Whole blood high dimensional single cell functional profiling of basophils in peanut allergy

Article Type: Letter to the EditorTitle : The impact of maternal-fetal omalizumab transfer on peanut-specific responses in an ex vivo placental perfusion model

Immune modulation is a key therapeutic tool for allergic diseases and asthma. It can be achieved in an antigen-specific way via allergen immunotherapy (AIT) or in endotype-driven approach using biologicals that target the major pathways of the type 2 (T2) immune response: IgE, IL-5 and IL-4/IL-13. COVID-19 vaccine provides an excellent opportunity to tackle the global pandemics and is currently being applied in an accelerated rhythm worldwide. It works as well through immune modulation. Thus, as there is an obvious interference between these treatment modalities recommendations on how they should be applied in sequence are expected. The European Academy of Allergy and Clinical Immunology (EAACI) gathered an outstanding expert panel under its Research and Outreach Committee (ROC). This expert panel was called to evaluate the evidence and formulate recommendation on the administration of COVID-19 vaccine in patients with allergic diseases and asthma receiving AIT or biologicals. The panel also formulated recommendations for COVID-19 vaccine in association with biologicals targeting the type 1 or type 3 immune response. In formulating recommendations, the panel evaluated the mechanisms of COVID-19 infection, of COVID-19 vaccine, of AIT and of biologicals and considered the data published for other anti-infectious vaccines administered concurrently with AIT or biologicals.

Advances in molecular biology alongside the accelerated development of gene and cell engineering have contributed to the development of several endotype-targeted biological therapies against chronic immune-mediated allergic diseases. Conventional therapies for asthma, chronic rhinosinusitis with polyposis (CRSwNP), chronic spontaneous urticaria and atopic dermatitis (AD) are not without limitations, and as such the advent of biological therapies have provided a promising alternative treatment option. Biologicals have proven efficacious in the treatment of refractory chronic spontaneous urticaria, asthma, AD, CRSwNP and there is increasing evidence for their utility in treating food allergy. Biologicals are applied and investigated for the most urgent need: acute treatment, symptom control and reduction of steroid usage. Currently there are five approved biologicals for allergic disease management, targeted against IgE (omalizumab), type 2 (T2) cytokines and cytokine receptors (IL-4Ra; dupilumab, IL-5; mepolizumab/reslizumab, IL-5Ra; benralizumab).

Vaccines are essential public health tools with a favorable safety profile and prophylactic effectiveness that have historically played significant roles in reducing infectious disease burden in populations, when the majority of individuals are vaccinated. The COVID-19 vaccines are expected to have similar positive impacts on health across the globe. While serious allergic reactions to vaccines are rare, their underlying mechanisms and implications for clinical management should be considered to provide individuals with the safest care possible. In this review, we provide an overview of different types of allergic adverse reactions that can potentially occur after vaccination and individual vaccine components capable of causing the allergic adverse reactions. We present the incidence of allergic adverse reactions during clinical studies and through post-authorization and post-marketing surveillance and provide plausible causes of these reactions based on potential allergenic components present in several common vaccines. Additionally, we review implications for individual diagnosis and management and vaccine manufacturing overall. Finally, we suggest areas for future research.

This systematic review evaluates the efficacy and safety of biologicals for chronic rhinosinusitis with nasal polyps (CRSwNP) compared to the standard of care. Pubmed, EMBASE and Cochrane Library were searched for RCTs. Critical and important CRSwNP-related outcomes were considered. The risk of bias and the certainty of the evidence were assessed using GRADE. RCTs evaluated (dupilumab-2, omalizumab-4, mepolizumab-2, reslizumab-1) included 1236 adults, with follow-up 20-64 weeks. Dupilumab reduces the need for surgery (NFS) and oral corticosteroid (OCS) use (RR 0.28; 95%CI 0.20-0.39, moderate certainty) and improves with high certainty smell (mean difference (MD) +10.54; 95%CI +9.24 to +11.84) and quality of life (QoL) (MD -19.14; 95%CI 95%CI -22.80 to -15.47), with fewer treatment-related adverse events (TAEs) (RR 0.95; 95%CI 0.89-1.02, moderate certainty). Omalizumab reduces NFS (RR 0.85; 95%CI 0.78 to 0.92, high certainty), decreases OCS use (RR 0.38; 95%CI 0.10-1.38, moderate certainty), improves with high certainty smell (MD +3.84; 95%CI +3.64 to +4.04) and QoL (MD -15.65; 95%CI -16.16 to -15.13), with increased TAE (RR 1.73; 95%CI 0.60-5.03, moderate certainty). There is low certainty for mepolizumab reducing NFS (RR 0.78; 95%CI 0.64 to 0.94) and improving QoL (MD -13.3; 95% CI -23.93 to -2.67) and smell (MD +0.7; 95%CI -0.48 to +1.88), with increased TAEs (RR 1.64; 95%CI 0.41-6.50). The evidence for reslizumab is very uncertain.

Allergic diseases like asthma, allergic rhinitis, or food allergy have a high prevalence in women of childbearing age and may affect up to 30% of this age group. A multitude of immunological changes characterizes pregnancy to create the optimal milieu for the unborn child. Both these immunological changes and pre-conceptional, sub-optimal disease control may affect the severity of the respective allergic disease manifestations during pregnancy and pose a risk for mother and child. Due to apparent limitations in conducting clinical trials, safety data on anti-allergic drugs during pregnancy are limited. This lack of clinical evidence demands to counsel between potential and known risks and benefits of anti-allergic drugs. This includes the potential of disease aggravation in the absence of treatment. By doing so, informed decisions and shared decision-making is facilitated. In particular, in patients with severe asthma, education about the risk of uncontrolled asthma for mother and child should be part of regular care. This review focuses on the management of allergic diseases during pregnancy, maternal counseling, and available information/evidence regarding allergic diseases’ management and treatment during pregnancy. Furthermore, we discuss the challenges of treating patients with allergic diseases and covid-19 during pregnancy.

Article Type: News and Views: Groundbreaking Discoveries in ImmunologyTitle: Emollients for the prevention of atopic dermatitisAuthors: Akash Kothari1(https://orcid.org/0000-0003-1980-161X), Arielle Locke2,Thomas Eiwegger1,3,4(https://orcid.org/0000-0002-2914-7829)1Translational Medicine Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada2Department of Medicine, National University of Ireland, Galway, Ireland3Division of Immunology and Allergy, Food Allergy and Anaphylaxis Program, The Department of Pediatrics, Hospital for Sick Children, Toronto, Ontario, Canada4Department of Immunology, Faculty of Medicine, University of Toronto, Toronto, Ontario, CanadaCorrespondence to: Thomas Eiwegger, MD, Division of Immunology and Allergy, Food Allergy and Anaphylaxis Program, The Department of Paediatrics, Hospital for Sick Children, 555 University Ave, Toronto, Canada, E-mail: thomas.eiwegger@sickkids.ca, Tel.: +1 416-813-7654 ext. 1862Conflicts of Interest: AK and AL have nothing to disclose. TE reports to act as local PI for company sponsored trials by DBV and sub-investigator for Regeneron, holds grants from Innovation Fund Denmark, CIHR outside the submitted work. He is Co-Investigator or scientific lead in three investigator initiated oral immunotherapy trials supported by the Food Allergy and Anaphylaxis Program SickKids and serves as associate editor for Allergy. He/his lab received unconditional/in-kind contributions from Macro Array Diagnostics and an unrestricted grant from ALK. He holds advisory board roles for ALK.Financial support: This work was supported by The Hospital for Sick Children, The Food Allergy and Anaphylaxis Program at The Hospital for Sick Children, and The Dr Lorus J And Dr Margery J Milne Scholarship from Victoria University at the University of Toronto.Statement of Author Contribution: All authors critically reviewed the original articles (references 6 and 7) and wrote the News & Views: Groundbreaking discoveries in Immunology article. All authors contributed, revised, edited, and approved the final version of the manuscript as submitted and agreed to be accountable for all aspects of the work.Keywords: emollient, atopic eczema, infancyAbbreviations : food allergy, FA; filaggrin gene, FLG; atopic dermatitis, AD; transepidermal water loss, TEWL; Barrier Enhancement for Eczema Prevention, BEEP; Preventing Atopic Dermatitis and Allergies, PreventADALL