Circulating serum profile of small non-coding RNAs in patients with anaphylaxis beyond microRNAs

Introduction

Anaphylaxis is the most severe manifestation of allergic disorders. Currently, an increasing number of cells, pathways and molecules involved in the etiopathogenesis of anaphylaxis are being discovered. However, there are no conclusive biomarkers to confirm its diagnosis. Small non-coding RNAs (sncRNAs) are 18-200 nucleotide molecules that can be divided into: microRNAs (miRNAs), Piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), small nuclear RNAs (snRNAs), transference RNA derived fragments (tRFs) and YRNA derived fragments (YRFs). These molecules participate in cell-cell communication modulating various physiological processes and have been postulated as non-invasive biomarkers of several pathologies. Therefore, in this study we characterized the serum circulating profile of other sncRNA beyond miRNAs in two populations of 5 adults and 5 children with drug- and food-mediated anaphylaxis, respectively.

Methods

Samples were obtained from each patient under two different conditions: during anaphylaxis and 14 days after the reaction (control). The sncRNA analysis was carried out by Next Generation Sequencing (NGS).

Results

A total of 671 sncRNAs (3 piRNAs, 74 snoRNAs, 54 snRNAs, 348 tRFs and 192 YRFs) were identified in adults with drug-induced anaphylaxis, while 612 sncRNAs (2 piRNAs, 73 snoRNAs, 52 snRNAs, 321 tRFs and 164 YRFs) were characterized in children with food-mediated anaphylaxis. However, only 33 (1 piRNA, 4 snoRNAs, 1 snRNAs, 7 tRFs and 20 YRFs) and 80 (4 snoRNAs, 6 snRNAs, 54 tRFs and 16 YRFs) of them were statistically different between both conditions, respectively. Among them, only three (Y_RNA.394, Y_RNA.781 and SCARNA2) were common to both adults and children analysis.

Discussion

This study provides a differential profile of circulating serum sncRNAs beyond miRNAs in patients with anaphylaxis, postulating them as candidate biomarkers for this pathological event and as novel mediators of the reaction.

Criteria used by health professionals on the selection of allergen immunotherapy in real clinical practice: Methodology

Background

Allergen immunotherapy (AIT) is today the only etiological therapy for respiratory allergic diseases, including allergic rhinitis, allergic conjunctivitis, and allergic asthma. Even though interest in real-world data has recently increased, publications mainly focus on short-term and long-term efficacy and safety of AIT. Indeed, information is still lacking regarding the "key parameters" or "drivers of prescription" used by doctors to prescribe AIT or by the patients to accept AIT as treatment for their respiratory allergic disease. Examining these factors is therefore the main goal of the CHOICE-Global Survey: "Criteria Used by Health Professionals on the Selection of Allergen Immunotherapy in Real Clinical Practice: An international academic electronic survey".

Methods

We present the methodology of the CHOICE-Global Survey, an academic, prospective, multicenter, observational, transversal, web-based e-survey, conducted in real-life clinical settings designed to collect data from 31 countries representing 9 global different socio-economic and demographic regions. In the present document, we describe the survey, how it was conceived and developed, how data are stored and analyzed, and the different steps that will provide this information to the allergy community.

Conclusions

The CHOICE-Global Survey will be able to provide, from an academic point of view, information on the drivers of prescription of AIT in real-life practice and improve understanding regarding the key parameters considered by doctors and patients for such therapy.

Children and caregiver proxy quality of life from peanut oral immunotherapy trials

BACKGROUND

Health-related quality of life (HRQoL) is significantly and substantially reduced in individuals with peanut allergy due to many factors associated with unanticipated or potentially fatal reactions. Further insight on the impact of peanut oral immunotherapy in managing peanut allergy on HRQoL is needed. The aim of this analysis was to assess effects of peanut (Arachis hypogaea) allergen powder-dnfp (PTAH), a biologic drug for peanut oral immunotherapy, on HRQoL from three phase 3 and two follow-on trials of PTAH.

METHODS

HRQoL assessments from participants aged 4-17 in the PALISADE (ARC003), ARC004 (PALISADE follow-on), ARTEMIS (ARC010), RAMSES (ARC007), and ARC011 (RAMSES follow-on) trials were included in this analysis. Responses on the Food Allergy Quality of Life Questionnaire (FAQLQ) and Food Allergy Independent Measure (FAIM) were evaluated by age group and respondent (self or caregiver proxy). Data were analyzed with descriptive statistics and Student t tests.

RESULTS

Baseline FAQLQ and FAIM total scores appeared comparable between PTAH- and placebo-treated participants. Self and caregiver proxy-reported total scores on the FAQLQ for PTAH-treated participants generally improved at trial exit versus baseline; FAIM total scores improved throughout all trials. The tendency for improvement in FAQLQ total scores from baseline for PTAH appeared larger in self versus caregiver proxy-reports. Between treatment groups, PTAH was generally favored in the PALISADE and ARTEMIS trials; differences varied in the RAMSES trial based on age and respondent types.

CONCLUSIONS

PTAH for the management of peanut allergy in children appeared to have a beneficial effect on HRQoL in trials. Improvements were seen despite rigors of trial participation.

Allergen immunotherapy and/or biologicals for IgE-mediated food allergy: A systematic review and meta-analysis

Background

There is substantial interest in immunotherapy and biologicals in IgE‐mediated food allergy.

Methods

We searched six databases for randomized controlled trials about immunotherapy alone or with biologicals (to April 2021) or biological monotherapy (to September 2021) in food allergy confirmed by oral food challenge. We pooled the data using random‐effects meta‐analysis.

Results

We included 36 trials about immunotherapy with 2126 mainly child participants. Oral immunotherapy increased tolerance whilst on therapy for peanut (RR 9.9, 95% CI 4.5.–21.4, high certainty); cow's milk (RR 5.7, 1.9–16.7, moderate certainty) and hen's egg allergy (RR 8.9, 4.4–18, moderate certainty). The number needed to treat to increase tolerance to a single dose of 300 mg or 1000 mg peanut protein was 2.

Oral immunotherapy did not increase adverse reactions (RR 1.1, 1.0–1.2, low certainty) or severe reactions in peanut allergy (RR 1,6, 0.7–3.5, low certainty), but may increase (mild) adverse reactions in cow's milk (RR 3.9, 2.1–7.5, low certainty) and hen's egg allergy (RR 7.0, 2.4–19.8, moderate certainty). Epicutaneous immunotherapy increased tolerance whilst on therapy for peanut (RR 2.6, 1.8–3.8, moderate certainty). Results were unclear for other allergies and administration routes.

There were too few trials of biologicals alone (3) or with immunotherapy (1) to draw conclusions.

Conclusions

Oral immunotherapy improves tolerance whilst on therapy and is probably safe in peanut, cow's milk and hen's egg allergy. More research is needed about quality of life, cost and biologicals.

Food immunotherapy practice: Nation differences across Europe, the FIND project

BACKGROUND

Food allergen immunotherapy (FA-AIT) practice is known to vary globally. This project aims to identify and characterize European centres performing FA-AIT.

METHODS

An EAACI task force conducted an online survey to gather relevant information regarding FA-AIT practice and setting-specific resources after reviewing the published literature and congress abstracts throughout Europe.

RESULTS

We identified 102 FA-AIT centres in 18 countries; only Spain (n = 39) and France (n = 16) had ≥10 such centres. Overall, most facilities were hospital-based (77.5%), publicly funded (80.4%) and delivered FA-AIT as routine clinical care (80.4%). On average, departments had 3 allergists/paediatric allergists and 2 nurses. Surveyed centres had provided FA-AIT for a median of 9 years [1-24] to a median of 105 [5-2415] patients. The estimated total number of treated patients was 24875, of whom 41.3% received AIT for milk, 34.2% egg, 12.8% peanut and 11.7% other foods. Anaphylaxis to AIT doses requiring over 4-6 h of observation was reported by 70.6% of centres, ICU admissions by 10.8% and eosinophilic esophagitis by 45.1%. Quality of life and sustained unresponsiveness were evaluated in 20.6% and 54.9% of centres, respectively. The main contraindications for food AIT were severe asthma (57%-63%), eosinophilic esophagitis (56%-48%) and age below 5 years (47%-41%).

CONCLUSIONS

In Europe, FA-AIT is provided mostly in clinical practice. Significant variation is seen in the number of centres per country, facility characteristics and inclusion/exclusion criteria, and in certain aspects of protocols. Potential inequality in access to AIT has been identified as well as the need for education and guidance for treatment standardization.

Effect of synbiotic supplementation on children with atopic dermatitis: an observational prospective study

The objective of this observational single-cohort prospective study was to assess the effect of synbiotic supplementation for 8 weeks in children with atopic dermatitis (AD). The synbiotic product contained Lactobacillus casei, Bifidobacterium lactis, Lactobacillus rhamnosus, Lactobacillus plantarum, fructooligosaccharide, galactooligosaccharide, and biotin. Patients were examined at baseline and at 8 weeks. Effectiveness of treatment was assessed with the Scoring Atopic Dermatitis (SCORAD) index. A total of 320 children (mean age 5.1 years, range 0-12 years) were included. The mean (SD) SCORAD index decreased from 45.5 (15.5) at baseline to 19.4 (14.6) at the end of treatment (P < 0.001), VAS score for pruritus decreased from 5.7 (2.2) to 2.3 (2.2) (P < 0.001), and VAS score for sleep decreased from 3.1 (2.5) to 1.1 (1.8) (P < 0.001). Percentage of children with moderate-severe disease decreased from 92.4% at baseline to 28.1% at week 8. In the multiple linear regression analysis, higher baseline SCORAD index (OR 0.51; 95% CI 0.41-0.61) and higher adherence (OR 7.29; 95% CI 1.85-12.73) were significantly associated with greater decrease in SCORAD index.Conclusion: Supplementation with the multistrain synbiotic product may improve AD in children. What is known: • Pediatric atopic dermatitis (AD) is a common, troublesome condition with limited treatment options, which has been shown to be associated with dysbiosis in the intestinal microflora. • Results of controlled clinical trials (RCTs) on the effect of probiotics in children with AD have been disparate, although overall, the data favor probiotics over placebo, with multistrain supplements associated with better improvements in AD. What is new: • The results of this observational, prospective, open-label, single-cohort study on 320 children with AD younger than 12 years old suggest that supplementation with multistrain synbiotics (Lactobacillus casei, Bifidobacterium lactis, Lactobacillus rhamnosus, Lactobacillus plantarum, fructooligosaccharide, galactooligosaccharide, and biotin) helps to improve AD symptoms in children. • More than 80% of children experienced improvement in AD symptoms, as measured by Severity Scoring of Atopic Dermatitis (SCORAD) index and assessed by parents and physicians. The main predictive factors for improvement was adherence to synbiotic treatment and high baseline SCORE index; the change in SCORAD did not depend on age, gender, presence of concomitant treatment, duration, and type of AD (persistent vs with flares), other concomitant allergies or history of parental allergy.

Exercise-induced bronchospasm diagnosis in children. Utility of combined lung function tests

BACKGROUND

The diagnosis of exercise-induced asthma or bronchospasm (EIB) is a complex dare in daily clinical practice. The consensus is that if bronchial hyper-responsiveness (BHR) is demonstrated in a patient with symptoms consistent with EIB, then that patient can be diagnosed with exercise-induced bronchospasm. The aim of this study was to determine which BHR test is the most efficient to diagnose EIB.

METHODS

Children under 16, without previous asthma diagnosis, or with stable asthma, complaining of asthma-like symptoms triggered by exercise were included. Bronchodilator, methacholine, mannitol, and exercise tests were performed on all patients, following established protocols. The performance of single and combined tests was determined.

RESULTS

Of 46 patients (median age: 12 yr, ranged 8-16 y.o.) were recruited, 30 (70%) previously diagnosed of asthma. BHR was detected in 93.47% of the children. The exercise challenge test detected BHR in 11 of 46 (23.90%) patients, bronchodilator test in 10 of 46 (21.70%), mannitol in 36 of 45 (80%) and methacholine in 41 of 45 (91.11%). The total number of patients with BHR was detected using a combination of the methacholine and mannitol tests. A combination of the methacholine test performed first, followed by the mannitol test, was able to diagnose BHR in 100% of children with lower number of tests (n = 45) than if the order was reversed (n = 50).

CONCLUSIONS

Methacholine and mannitol tests detect BHR in most children with suspected EIB. Bronchodilator and exercise tests show a low positivity rate. A combination of the methacholine test, followed by the mannitol test, gives the highest return to identify BHR in children for the diagnosis of EIB.

Misregulation of suppressors of cytokine signaling in eosinophilic esophagitis

BACKGROUND

Several findings suggest that eosinophilic esophagitis (EoE) is strongly associated with atopy and allergen-driven, Th2-type immune responses, indicating the association of EoE with immune dysregulation. The objective of this study is to ascertain the molecular mechanism involved in EoE disease development a Th2 condition.

METHODS

25 patients with diagnosis of EoE and 17 non-EoE controls were recruited by the gastroenterology and allergy departments from three different hospitals. Transcription analysis of suppressors of cytokine signaling 1, 3, 5 (SOCS), interleukin-5 (IL), IL-13, eotaxin (CCL26), eoataxin receptor (CCR3), and mitogen-activated protein kinase 1 (MAPK1) was performed in esophageal biopsies by real time PCR. Western blot of ERK esophageal protein and additional measures of IL-5 and VEGF levels in serum were performed.

RESULTS

The esophagus of EoE patients expresses and synthesizes high levels of SOCS1 and SOCS3 proteins (P < 0.05), and these expression correlated with levels of IL-5, IL-13, CCL26, CCR3, and MAPK1 genes. In addition, we demonstrate the implication of the ERK pathway (P < 0.001).

CONCLUSIONS

SOCS proteins probably contribute to EoE pathogenesis by directly or indirectly inducing the Th2 profile, as well as by promoting the production of Th2 cytokines. All these findings further enhance our understanding of the mechanism of EoE, and accumulating evidence suggests that EoE pathogenesis is likely to be due to misregulation of immunological pathways.

Dehydrated egg white: an allergen source for improving efficacy and safety in the diagnosis and treatment for egg allergy

BACKGROUND

Raw and cooked eggs are used as allergens in oral food challenge (OFC). Raw egg is the best option, as it keeps proteins intact and retains their allergenicity, albeit microbiologically safe manipulation is difficult. Therefore, the use of dehydrated egg white (DEW) could improve the efficacy and safety profile of OFC. The aim of the study was to compare the allergenicity of DEW, a product that undergoes a double heat treatment (pasteurization and drying), with that of raw egg white (REW) and determine the efficacy of DEW in the diagnosis of egg allergy.

METHODS

We conducted a prospective study of 40 egg-allergic patients who visited our outpatient clinic. Each patient underwent OFC with DEW and REW to determine the correlation between the tests. DEW and REW extracts were analyzed using SDS-PAGE. We compared the allergenicity of both extracts using IgE immunoblotting with a serum pool from patients with positive OFC results.

RESULTS

Ten patients (25%) had positive OFC results with both DEW and REW, and the doses that triggered an allergic reaction in each patient were similar (p > 0.05). All 30 patients (75%) with a negative OFC result with DEW also had negative OFC results with REW. SDS-PAGE and IgE immunoblotting revealed that the protein composition and IgE-binding capacity of both extracts were virtually identical.

CONCLUSIONS

This is the first time that it is shown that the allergenicity of commercially available DEW is equivalent to raw egg whites. In vivo and in vitro tests showed that processing of DEW does not affect the allergenicity of egg proteins. DEW is an effective and microbiologically safer source of allergen for the diagnosis of egg allergy. Furthermore, DEW can be used in egg oral immunotherapy.

Allergy to goat's and sheep's milk in a population of cow's milk-allergic children treated with oral immunotherapy

BACKGROUND

Cow's milk oral immunotherapy (CMOIT) is a recognized treatment for persistent cow's milk (CM) allergy. However, further data are necessary on tolerance to milk from other mammals.

OBJECTIVE

To describe the clinical and immunologic features of goat's and sheep's milk (GSM) allergy in patients who tolerated CM after CMOIT.

METHODS

Fifty-eight CM-allergic patients who successfully underwent CMOIT in our department were evaluated using skin prick test (SPT), specific immunoglobulin (Ig) E determination, enzyme-linked immunoassay (ELISA), and controlled oral challenge to assess allergy to GSM. Statistical analysis was carried out to identify markers of allergy to GSM.

RESULTS

  Fifteen of 58 (25.9%) patients were allergic to either goat's or sheep's milk or to both, as confirmed by a controlled positive oral challenge. Forty-seven percent of all positive oral challenges were classified as anaphylactic reactions. Specific IgE to CM casein, goat's whole milk, and sheep's whole milk was 13.2, 18.0, and 21.4 kU(A)/l in the group of GSM-allergic patients and 6.6, 6.5, and 6.5 kU(A) /l in the GSM-non-allergic patients (p < 0.05). Decision-making cut-off points based on sIgE for diagnosing symptomatic GSM allergy could not be determined. ELISA inhibition assays showed limited cross-reactivity (up to 77.2%) between CM casein and GSM casein in the group of GSM-allergic patients in contrast with almost 100% in GSM-not-allergic patients.

CONCLUSION

We found a high prevalence (26%) of allergy to GSM in our population of CM-allergic children treated with oral immunotherapy. Therefore, tolerance to GSM should be assessed in order to provide accurate nutritional advice and minimize life-threatening accidental intake. Specific IgE to CM casein, goat's and sheep's whole milk is a good marker of this allergy. Although CM oral immunotherapy is a specific treatment for CM allergy, it may not be effective against allergy to the milk of other mammals.

Efficacy of oral immunotherapy protocol for specific oral tolerance induction in children with cow's milk allergy

BACKGROUND

In the last two decades milkoralimmunotherapy has gained interest as an effective treatment option for milk-allergic patients.

OBJECTIVES

To report on the efficacy of a milk oral immunotherapy.

METHODS

Children with immunoglobulin E-mediated cow's milk allergy were included in the protocol. The treatment consisted of an induction phase in which milk doses were increased weekly in the hospital, while the tolerated dose was continued daily at home. The goal was to achieve a minimum milk intake of 200 ml a day. During the maintenance phase, patients ingested at least 200 ml of milk in a single dose every day.

RESULTS

The protocol was applied to 105 milk-allergic children diagnosed by specific IgE to milk and controlled oral food challenge. The mean duration of the induction phase was 19 weeks. Of the 105 subjects, 86 (81.9%) successfully complied with the protocol and 19 (19.1%) failed. Causes of failure were moderate/severe reactions in 12 patients (12.44%) and personal reasons in 7 (6.66%). A total of 182 adverse reactions occurred during the induction phase, most of them mild. Baseline specific IgE to milk and casein was significantly lower (P < 0.05) in the successfully treated group compared to the group in which the treatment failed.

CONCLUSIONS

Milk oral immunotherapy is a safe and effective treatment for milk-allergic children, although adverse reactions may occur. Baseline milk and casein-specific IgE may be useful to predict a good response to milk oral immunotherapy.