CD8(+) T cell differentiation status correlates with the feasibility of sustained unresponsiveness following oral immunotherapy

Multiomics approaches disclose very-early molecular and cellular switches during insect-venom allergen-specific immunotherapy: an observational study

Allergen-specific immunotherapy (AIT) induces immune tolerance, showing the highest success rate (>95%) for insect venom while a much lower chance for pollen allergy. However, the molecular switches leading to successful durable tolerance restoration remain elusive. The primary outcome of this observational study is the comprehensive immunological cellular characterization during the AIT initiation phase, whereas the secondary outcomes are the serological and Th2-cell-type-specific transcriptomic analyses. Here we apply a multilayer-omics approach to reveal dynamic peripheral immune landscapes during the AIT-initiation phase in venom allergy patients (VAP) versus pollen-allergic and healthy controls. Already at baseline, VAP exhibit altered abundances of several cell types, including classical monocytes (cMono), CD4+ hybrid type 1-type 17 cells (Th1-Th17 or Th1/17) and CD8+ counterparts (Tc1-Tc17 or Tc1/17). At 8-24 h following AIT launch in VAP, we identify a uniform AIT-elicited pulse of late-transitional/IL-10-producing B cells, IL-6 signaling within Th2 cells and non-inflammatory serum-IL-6 levels. Sequential induction of activation and survival protein markers also immediately occur. A disequilibrium between serum IL-6 and cMono in VAP baseline is restored at day seven following AIT launch. Our longitudinal analysis discovers molecular switches during initiation-phase insect-venom AIT that secure long-term outcomes. Trial number: NCT02931955.

Enhanced Effect of β-Lactoglobulin Immunization in Mice with Mild Intestinal Deterioration Caused by Low-Dose Dextran Sulphate Sodium: A New Experimental Approach to Allergy Studies

BACKGROUND/OBJECTIVES

Cow's milk allergy is one of the most common food allergies in children, and its pathomechanism is still under investigation. Recently, an increasing number of studies have linked food allergy to intestinal barrier dysfunction. The present study aimed to investigate changes in the intestinal microenvironment during the development of β-lactoglobulin (β-lg) allergy under conditions of early intestinal dysfunction.

METHODS

BALB/c mice received intraperitoneal β-lg with Freund's adjuvant, followed by oral β-lg while receiving dextran sulphate sodium salt (DSS) in their drinking water (0.2% w/v). The immunized group without DSS and the groups receiving saline, oral β-lg, or DSS served as controls.

RESULTS

The study showed that the immunization effect was greater in mice with mild intestinal barrier dysfunction. Although DSS did not affect the mice's humoral response to β-lg, in combination with β-lg, it significantly altered their cellular response, affecting the induction and distribution of T cells in the inductive and peripheral tissues and the activation of immune mediators. Administration of β-lg to sensitized mice receiving DSS increased disease activity index (DAI) scores and pro-inflammatory cytokine activity, altered the distribution of claudins and zonulin 1 (ZO-1) in the colonic tissue, and negatively affected the balance and activity of the gut microbiota.

CONCLUSIONS

The research model used appears attractive for studying food allergen sensitization, particularly in relation to the initial events leading to mucosal inflammation and the development of food hypersensitivity.

Parameter optimization for stable clustering using FlowSOM: a case study from CyTOF

High-dimensional cell phenotyping is a powerful tool to study molecular and cellular changes in health and diseases. CyTOF enables high-dimensional cell phenotyping using tens of surface and intra-cellular markers. To utilize the full potential of CyTOF, we need advanced clustering and machine learning methodologies to enable automated gating of the complex data. Here we show that critical modifications to a machine learning based FlowSOM package and precise parameter optimization can enable us to reliably analyze the complex CyTOF data. We show the impact of key parameters on clustering outcomes while addressing bugs within the publicly available package. We modified the FlowSOM pipeline to fix the bugs, enable scalability to handle large datasets and perform parameter optimization. We further validated this modified pipeline on a substantial external immunological dataset demonstrating the need of data-specific tailored parameter optimization to ensure reliable definition and interrogation of immune cell populations associated with immune disorders.

Atopic dermatitis and IgE-mediated food allergy: Common biologic targets for therapy and prevention

OBJECTIVE

To highlight common mechanistic targets for the treatment of atopic dermatitis (AD) and IgE-mediated food allergy (IgE-FA) with potential to be effective for both diseases and prevent atopic progression.

DATA SOURCES

Data sources were PubMed searches or National Clinical Trials (NCT)-registered clinical trials related to AD, IgE-FA, and other atopic conditions, especially focused on the pediatric population.

STUDY SELECTIONS

Human seminal studies and/or articles published in the past decade were emphasized with reference to preclinical models when relevant. NCT-registered clinical trials were filtered by inclusion of pediatric subjects younger than 18 years with special focus on children younger than 12 years as a critical period when AD and IgE-FA diseases may often be concurrent.

RESULTS

AD and IgE-FA share several pathophysiologic features, including epithelial barrier dysfunction, innate and adaptive immune abnormalities, and microbial dysbiosis, which may be critical for the clinical progression between these diseases. Revolutionary advances in targeted biologic therapies have shown the benefit of inhibiting type 2 immune responses, using dupilumab (anti-interleukin-4Rα) or omalizumab (anti-IgE), to potentially reduce symptom burden for both diseases in pediatric populations. Although the potential for biologics to promote disease remission (AD) or sustained unresponsiveness (IgE-FA) remains unclear, the refinement of biomarkers to predict infants at risk for atopic disorders provides promise for prevention through timely intervention.

CONCLUSION

AD and IgE-FA exhibit common features that may be leveraged to develop biologic therapeutic strategies to treat both conditions and even prevent atopic progression. Future studies should be designed with consistent age stratification in the pediatric population and standardized regimens of adjuvant oral immunotherapy or dose escalation (IgE-FA) to improve cross-study interpretation.

Low-dose oral immunotherapy in immunoglobulin E-mediated food allergies

Nowadays, the management of food allergies has increasingly moved from conventional oral immunotherapy (OIT) to low-dose OIT or low-dose OIT utilizing hypoallergenic foods. This shift is largely because the latter appears to induce oral tolerance with fewer adverse effects than the former. However, the mechanisms underpinning such differences remain unclear. To better understand these mechanisms, we conducted a comparative study scrutinizing the mechanisms of OIT, especially those of low-dose desensitization. We also summarized articles on low-dose OIT and low-dose OIT using hypoallergenic foods. We examined the efficacy, safety, and immunological parameters of low-dose OIT and those of low-dose OIT with hypoallergenic foods with the aim of shedding some light on low-dose OIT and its therapeutic application in inducing oral tolerance for individuals with food allergies.

Immune signatures predicting the clinical outcome of peanut oral immunotherapy: where we stand

Peanut allergy is a growing health concern that can cause mild to severe anaphylaxis as well as reduced quality of life in patients and their families. Oral immunotherapy is an important therapeutic intervention that aims to reshape the immune system toward a higher threshold dose reactivity and sustained unresponsiveness in some patients. From an immunological point of view, young patients, especially those under 3 years old, seem to have the best chance for therapy success. To date, surrogate markers for therapy duration and response are evasive. We provide a comprehensive overview of the current literature state regarding immune signatures evolving over the course of oral immunotherapy as well as baseline immune conditions prior to the initiation of treatment. Although research comparing clinical and immune traits in the first years of life vs. later stages across different age groups is limited, promising insights are available on immunological endotypes among peanut-allergic patients. The available data call for continued research to fill in gaps in knowledge, possibly in an integrated manner, to design novel precision health approaches for advanced therapeutic interventions in peanut allergy.

Peanut allergy: risk factors, immune mechanisms, and best practices for oral immunotherapy success

INTRODUCTION

Peanut oral immunotherapy (pOIT) is the only FDA-approved treatment for food allergy and its adoption amongst allergist immunologists and their patients is growing. pOIT is the subject of numerous clinical trials, however, the focus is often on treatment efficacy, safety, and tolerability, rather than identifying patients most likely to benefit from pOIT. Here, we review existing data on the clinical and immunological outcomes of pOIT that inform best practices for pOIT candidate selection.

AREAS COVERED

In this review, we describe the natural history of peanut allergy, summarize immunological and clinical outcomes of pOIT at different ages, discuss the optimization of pOIT in key age groups, and finally suggest an ideal age range at which to initiate pOIT for best outcomes.

EXPERT OPINION

pOIT is currently underutilized by patients and allergist-immunologists. Developing guidelines for selecting appropriate patients and optimizing treatment may help to increase access to pOIT. Many aspects of pOIT need additional study to further our understanding of the optimal timing to start pOIT, with careful consideration to clinical, immunological, and quality of life outcomes.