Skin as the target for allergy prevention and treatment

The fact that genetic and environmental factors could trigger disruption of the epithelial barrier and subsequently initiate a TH2 inflammatory cascade conversely proposes that protecting the same barrier and promoting adequate interactions with other organs, such as the gut, may be crucial for lowering the risk and preventing atopic diseases, particularly, food allergies. In this review, we provide an overview of structural characteristics that support the epithelial barrier hypothesis in patients with atopic dermatitis, including the most relevant filaggrin gene mutations, the recent discovery of the role of the transient receptor potential vanilloid 1, and the role involvement of the microbiome in healthy and damaged skin. We present experimental and human studies that support the mechanisms of allergen penetration, particularly the dual allergen exposure and the outside-in, inside-out, and outside-inside-outside hypotheses. We discuss classic skin-targeted therapies for food allergy prevention, including moisturizers, steroids, and topical calcineurin inhibitors, along with pioneering trials proposed to change their current use (Prevention of Allergy via Cutaneous Intervention and Stopping Eczema and ALlergy). We provide an overview of the novel therapies that enhance the skin barrier, such as probiotics and prebiotics topical application, read-through drugs, direct and indirect FLG replacement, and interleukin and janus kinases inhibitors. Last, we discuss the newer strategies for preventing and treating food allergies in the form of epicutaneous immunotherapy and the experimental use of single-dose of adeno-associated virus vector gene immunotherapy.

The Stress Phenotyping Framework: A multidisciplinary biobehavioral approach for assessing and therapeutically targeting maladaptive stress physiology

Although dysregulated stress biology is becoming increasingly recognized as a key driver of lifelong disparities in chronic disease, we presently have no validated biomarkers of toxic stress physiology; no biological, behavioral, or cognitive treatments specifically focused on normalizing toxic stress processes; and no agreed-upon guidelines for treating stress in the clinic or evaluating the efficacy of interventions that seek to reduce toxic stress and improve human functioning. We address these critical issues by (a) systematically describing key systems and mechanisms that are dysregulated by stress; (b) summarizing indicators, biomarkers, and instruments for assessing stress response systems; and (c) highlighting therapeutic approaches that can be used to normalize stress-related biopsychosocial functioning. We also present a novel multidisciplinary Stress Phenotyping Framework that can bring stress researchers and clinicians one step closer to realizing the goal of using precision medicine-based approaches to prevent and treat stress-associated health problems.

Pediatric eosinophilic esophagitis outcomes vary with co-morbid eczema and pollen food syndrome

Background

Eosinophilic esophagitis (EoE) is a chronic immune-mediated inflammatory disease characterized by eosinophil inflammation of the esophagus. It has been described as a component of the Allergic March and is often seen with other atopic diseases. Some atopic diseases, including asthma, are known to be heterogenous with endotypes that guide treatment. Similarly, we propose that EoE is a heterogenous disease with varying phenotypes and endotypes that might impact response to therapy.

Methods

A single-center retrospective review of pediatric patients ≤18 years of age diagnosed with EoE was conducted. All gastrointestinal clinic visits and esophagogastroduodenoscopies (EGD) from disease presentation through the first three years after diagnosis were reviewed. Histologic remission rate and therapies utilized [proton pump inhibitor (PPI), topical steroid, dietary elimination] were assessed.

Results

One hundred and thirty-seven patients were included, 80% of whom had at least one concurrent atopic condition at diagnosis, with food allergies being the most common (57%) followed by eczema (34%), and asthma (29%). The remission rate of the overall cohort was 65%, and by concurrent allergy, comorbid pollen food syndrome and eczema had the highest remission rates at 100% and 81%, respectively followed by asthma (62%), food allergies (62%), seasonal allergic rhinitis (60%), and history of anaphylaxis (56%). Kaplan-Meier curves for each atopic condition show that patients with eczema and pollen food syndrome achieve histologic remission faster than those without. All treatment modalities were more successful in patients with eczema than those without, and PPI was most effective treatment at inducing remission.

Conclusions

In a real-world pediatric cohort, 80% of patients with EoE had an underlying atopic condition. Patients with eczema and pollen food syndrome had a swifter response and were more likely to achieve histologic remission than patients with other atopic conditions. This study suggests that EoE, like other allergic diseases, may have heterogenous phenotypes that could affect response to treatment. There is currently a knowledge gap in classifying EoE based on endotypes and phenotypes at diagnosis and correlating responses to various treatment modalities.

Current insights: a systemic review of therapeutic options for peanut allergy

PURPOSE OF REVIEW

With increasing prevalence of peanut allergy (PA) globally and the greater risk of potential reactions occurring due to the leading role of nuts in food products, PA has become a significant public health concern over the past decade, affecting up to 5 million of the US adult population. This review details updates and advances in prevalence, diagnosis, and immunotherapies that have occurred over the past year.

RECENT FINDINGS

Therapeutic and diagnostic advances remain at the forefront of research and have continued to push the food allergy (FA) field forward to provide a promising role in the detection and treatment of PA. The FA field has researched significant advances in peanut immunotherapy, biomarker diagnosis, and quality of life (QoL) improvement.

SUMMARY

Given the burden and consequences for individuals with PA, these advances delivered in clinical practice can significantly improve the QoL of individuals with PA and their caregivers. Ongoing studies will continue to investigate long-term outcome measures of desensitisation and effective management plans tailored to the families' needs.

Early Introduction of Multi-Allergen Mixture for Prevention of Food Allergy: Pilot Study

The incidence and prevalence of food allergy (FA) is increasing. While several studies have established the safety and efficacy of early introduction of single allergens in infants for the prevention of FA, the exact dose, frequency, and number of allergens that can be safely introduced to infants, particularly in those at high or low risk of atopy, are still unclear. This 1-year pilot study evaluated the safety of the early introduction of single foods (milk, egg, or peanut) vs. two foods (milk/egg, egg/peanut, milk/peanut) vs. multiple foods (milk/egg/peanut/cashew/almond/shrimp/walnut/wheat/salmon/hazelnut at low, medium, or high doses) vs. no early introduction in 180 infants between 4-6 months of age. At the end of the study, they were evaluated for plasma biomarkers associated with food reactivity via standardized blood tests. Two to four years after the start of the study, participants were evaluated by standardized food challenges. The serving sizes for the single, double, and low dose mixtures were 300 mg total protein per day. The serving sizes for the medium and high dose mixtures were 900 mg and 3000 mg total protein, respectively. Equal parts of each protein were used for double or mixture foods. All infants were breastfed until at least six months of age. The results demonstrate that infants at either high or low risk for atopy were able to tolerate the early introduction of multiple allergenic foods with no increases in any safety issues, including eczema, FA, or food protein induced enterocolitis. The mixtures of foods at either low, medium, or high doses demonstrated trends for improvement in food challenge reactivity and plasma biomarkers compared to single and double food introductions. The results of this study suggest that the early introduction of foods, particularly simultaneous mixtures of many allergenic foods, may be safe and efficacious for preventing FA and can occur safely. These results need to be confirmed by larger randomized controlled studies.

Improvement in Health-Related Quality of Life in Food-Allergic Patients: A Meta-analysis

BACKGROUND

Food allergy (FA) is a growing global problem that can affect patients' health-related quality of life (HRQoL) owing to increased anxiety as well as social and economic restrictions. Interventions such as oral food challenges (OFCs) and oral immunotherapy (OIT) have been shown to improve HRQoL. However, meta-analyses and systematic synthesis of these data are lacking.

OBJECTIVE

To review and quantitatively synthesize potential benefits of interventions (OIT and OFC) systematically to address FA to a variety of foods.

METHODS

We conducted a systematic search through PubMed and Cochrane Medical Library databases and performed a meta-analysis focusing on studies assessing changes in HRQoL after OIT and/or OFCs in FA participants and caregivers from 2010 to July 2020. Random effects model and I² statistics were used to assess overall intervention effects and heterogeneity across studies.

RESULTS

We included 13 publications in this meta-analysis (OIT = 7; OFCs = 6). Mean change in HRQoL scores after OIT and OFCs was -1.25 (P < .001) and -0.78 (P = .052), with a significant I² of 87% (P < .001) and 90% (P < .001), respectively. Five OIT studies found significant improvements in HRQoL in the OIT group compared with the placebo group, with an overall standardized mean difference of -0.56 (P = .007; I² = 42%, P = .099).

CONCLUSIONS

This meta-analysis showed that in FA patients, both OIT and OFCs are associated with an improvement in HRQoL. Well-designed and long-term HRQoL studies are necessary to ascertain sustained benefits of OIT and OFCs.

Corrigendum: Analysis of a Large Standardized Food Challenge Data Set to Determine Predictors of Positive Outcome Across Multiple Allergens

[This corrects the article DOI: 10.3389/fimmu.2018.02689.].

Analysis of a Large Standardized Food Challenge Data Set to Determine Predictors of Positive Outcome Across Multiple Allergens

Background: Double-blind placebo-controlled food challenges (DBPCFCs) remain the gold standard for the diagnosis of food allergy; however, challenges require significant time and resources and place the patient at an increased risk for severe allergic adverse events. There have been continued efforts to identify alternative diagnostic methods to replace or minimize the need for oral food challenges (OFCs) in the diagnosis of food allergy.

Methods: Data was extracted for all IRB-approved, Stanford-initiated clinical protocols involving standardized screening OFCs to a cumulative dose of 500 mg protein to any of 11 food allergens in participants with elevated skin prick test (SPT) and/or specific IgE (sIgE) values to the challenged food across 7 sites. Baseline population characteristics, biomarkers, and challenge outcomes were analyzed to develop diagnostic criteria predictive of positive OFCs across multiple allergens in our multi-allergic cohorts.

Results: A total of 1247 OFCs completed by 427 participants were analyzed in this cohort. Eighty-five percent of all OFCs had positive challenges. A history of atopic dermatitis and multiple food allergies were significantly associated with a higher risk of positive OFCs. The majority of food-specific SPT, sIgE, and sIgE/total IgE (tIgE) thresholds calculated from cumulative tolerated dose (CTD)-dependent receiver operator curves (ROC) had high discrimination of OFC outcome (area under the curves > 0.75). Participants with values above the thresholds were more likely to have positive challenges.

Conclusions: This is the first study, to our knowledge, to not only adjust for tolerated allergen dose in predicting OFC outcome, but to also use this method to establish biomarker thresholds. The presented findings suggest that readily obtainable biomarker values and patient demographics may be of use in the prediction of OFC outcome and food allergy. In the subset of patients with SPT or sIgE values above the thresholds, values appear highly predictive of a positive OFC and true food allergy. While these values are relatively high, they may serve as an appropriate substitute for food challenges in clinical and research settings.

Eliciting Dose and Safety Outcomes From a Large Dataset of Standardized Multiple Food Challenges

Background: Food allergy prevalence has continued to rise over the past decade. While studies have reported threshold doses for multiple foods, large-scale multi-food allergen studies are lacking. Our goal was to identify threshold dose distributions and predictors of severe reactions during blinded oral food challenges (OFCs) in multi-food allergic patients. Methods: A retrospective chart review was performed on all Stanford-initiated clinical protocols involving standardized screening OFCs to any of 11 food allergens at 7 sites. Interval-censoring survival analysis was used to calculate eliciting dose (ED) curves for each food. Changes in severity and ED were also analyzed among participants who had repeated challenges to the same food. Results: Of 428 participants, 410 (96%) had at least one positive challenge (1445 standardized OFCs with 1054 total positive challenges). Participants undergoing peanut challenges had the highest ED₅₀ (29.9 mg), while those challenged with egg or pistachio had the lowest (7.07 or 1.7 mg, respectively). The most common adverse event was skin related (54%), followed by gastrointestinal (GI) events (33%). A history of asthma was associated with a significantly higher risk of a severe reaction (hazard ratio [HR]: 2.37, 95% confidence interval [CI]: 1.36, 4.13). Higher values of allergen-specific IgE (sIgE) and sIgE to total IgE ratio (sIgEr) were also associated with higher risk of a severe reaction (1.49 [1.19, 1.85] and 1.84 [1.30, 2.59], respectively). Participants undergoing cashew, peanut, pecan, sesame, and walnut challenges had more severe reactions as ED increased. In participants who underwent repeat challenges, the ED did not change (p = 0.66), but reactions were more severe (p = 0.02). Conclusions: Participants with a history of asthma, high sIgEr, and/or high values of sIgE were found to be at higher risk for severe reactions during food challenges. These findings may help to optimize food challenge dosing schemes in multi-food allergic, atopic patients, specifically at lower doses where the majority of reactions occur. Trials Registration Number: ClinicalTrials. gov number NCT03539692; https://clinicaltrials.gov/ct2/show/NCT03539692.

Advances in the Treatment of Food Allergy: Sublingual and Epicutaneous Immunotherapy

Food allergies continue to increase in prevalence. Standard care is a strict elimination diet, but life-threatening reactions still occur. Allergen immunotherapy has the most potential in treating food allergy. Subcutaneous immunotherapy has not been adopted into food allergy therapy. Oral immunotherapy has a high rate of adverse reactions. Sublingual immunotherapy (SLIT) uses the tolerogenic environment of the oral mucosa and epicutaneous immunotherapy (EPIT) uses the immune cells of the epidermis to transport antigens to afferent lymph nodes to activate immune responses. SLIT and EPIT can successfully desensitize patients. More research is needed to define optimal doses and administration protocols.

The association between asthma-related emergency department visits and pollen and mold spore concentrations in the Bronx, 2001-2008

BACKGROUND

The incidence of asthma morbidity and mortality is highest among minority inner-city populations. Among New York City's five boroughs, the Bronx has the highest rate of asthma-related hospitalizations and mortality. Outdoor air pollutants have been associated with increased asthma-related ED visits (AREDV) in this borough.

OBJECTIVE

To better understand the contribution of pollen and mold to asthma severity in the Bronx.

METHODS

The numbers of daily adult and pediatric AREDV and asthma-related hospitalizations (ARH) from 2001 to 2008 were obtained from two Bronx hospitals. AREDV and ARH data were acquired retrospectively through the Clinical Looking Glass data analysis software. Daily counts for tree, grass and weed pollen and mold spore counts from March 2001 to October 2008 were obtained from the Armonk counting station. All data were statistically analyzed and graphed as daily values.

RESULTS

There were a total of 42 065 AREDV and 10 132 ARH at both Bronx hospitals. There were spring and winter peaks of increased AREDV. Tree pollen counts significantly correlated with total AREDV (rho = 0.3639, p < 0.001), and pediatric (rho = 0.33, p < 0.001) and adult AREDV (rho = 0.28, p < 0.001). ARH positively correlated with tree pollen counts (Spearman rho = 0.2389, p < 0.001).

CONCLUSIONS

There exists a significant association between spring AREDV and ARH and tree pollen concentrations in a highly urbanized area such as the Bronx. Early anticipation of spring pollen peaks based on ongoing surveillance could potentially guide clinical practice and minimize asthma-related ED visits in the Bronx.