IL-1RL1a serum levels and IL1RL1 SNPs in the prediction of food allergy

Food Allergy Genetics and Epigenetics: A Review of Genome-Wide Association Studies

In this review, we provide an overview of food allergy genetics and epigenetics aimed at clinicians and researchers. This includes a brief review of the current understanding of genetic and epigenetic mechanisms, inheritance of food allergy, as well as a discussion of advantages and limitations of the different types of studies in genetic research. We specifically focus on the results of genome-wide association studies in food allergy, which have identified 16 genetic variants that reach genome-wide significance, many of which overlap with other allergic diseases, including asthma, atopic dermatitis, and allergic rhinitis. Identified genes for food allergy are mainly involved in epithelial barrier function (e.g., FLG, SERPINB7) and immune function (e.g., HLA, IL4). Epigenome-wide significant findings at 32 loci are also summarized as well as 14 additional loci with significance at a false discovery of < 1 × 10-4. Integration of epigenetic and genetic data is discussed in the context of disease mechanisms, many of which are shared with other allergic diseases. The potential utility of genetic and epigenetic discoveries is deliberated. In the future, genetic and epigenetic markers may offer ways to predict the presence or absence of clinical IgE-mediated food allergy among sensitized individuals, likelihood of development of natural tolerance, and response to immunotherapy.

Influence of Genetics on the Response to Omalizumab in Patients with Severe Uncontrolled Asthma with an Allergic Phenotype

Omalizumab is a monoclonal antibody indicated for the treatment of severe uncontrolled asthma with an allergic phenotype. Its effectiveness could be influenced by clinical variables and single nucleotide polymorphisms (SNPs) in one or more of the genes involved in the mechanism of action and process of response to omalizumab, and these could be used as predictive biomarkers of response. We conducted an observational retrospective cohort study that included patients with severe uncontrolled allergic asthma treated with omalizumab in a tertiary hospital. Satisfactory response after 12 months of treatment was defined as (1) Reduction ≥ 50% of exacerbations or no exacerbations, (2) Improvement of lung function ≥ 10% FEV1, and (3) Reduction ≥ 50% of OCS courses or no OCS. Polymorphisms in the FCER1A (rs2251746, rs2427837), FCER1B (rs1441586, rs573790, rs1054485, rs569108), C3 (rs2230199), FCGR2A (rs1801274), FCGR2B (rs3219018, rs1050501), FCGR3A (rs10127939, rs396991), IL1RL1 (rs1420101, rs17026974, rs1921622), and GATA2 (rs4857855) genes were analyzed by real-time polymerase chain reaction (PCR) using TaqMan probes. A total of 110 patients under treatment with omalizumab were recruited. After 12 months of treatment, the variables associated with a reduction in exacerbations were the absence of polyposis (odds ratio [OR] = 4.22; 95% confidence interval [CI] = 0.95-19.63), IL1RL1 rs17026974-AG (OR = 19.07; 95% CI = 1.27-547), and IL1RL1 rs17026974-GG (OR = 16.76; 95% CI = 1.22-438.76). Reduction in oral corticosteroids (OCS) was associated with age of starting omalizumab treatment (OR = 0.95; 95% CI = 0.91-0.99) and blood eosinophil levels > 300 cells/µL (OR = 2.93; 95% CI = 1.01-9.29). Improved lung function showed a relationship to the absence of chronic obstructive pulmonary disease (COPD) (OR = 12.16; 95% CI = 2.45-79.49), FCGR2B rs3219018-C (OR = 8.6; 95% CI = 1.12-117.15), GATA2 rs4857855-T (OR = 15.98; 95% CI = 1.52-519.57) and FCGR2A rs1801274-G (OR = 13.75; 95% CI = 2.14-142.68; AG vs. AA and OR = 7.46; 95% CI = 0.94-89.12; GG vs. AA). Meeting one response criterion was related to FCER1A rs2251746-TT (OR = 24; 95% CI = 0.77-804.57), meeting two to age of asthma diagnosis (OR = 0.93; 95% CI = 0.88-0.99), and meeting all three to body mass index (BMI) < 25 (OR = 14.23; 95% CI = 3.31-100.77) and C3 rs2230199-C (OR = 3; 95% CI = 1.01-9.92). The results of this study show the possible influence of the polymorphisms studied on the response to omalizumab and the clinical benefit that could be obtained by defining predictive biomarkers of treatment response.

Predictive Values of Serum IL-33 and sST2 in Endotypes and Postoperative Recurrence of Chronic Rhinosinusitis with Nasal Polyps

Background. Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common inflammatory disease with high heterogeneity and postoperative recidivation. The IL-33/ST2 axis is known to be involved in Th2 immune responses. This study is aimed at exploring levels of serum IL-33 and soluble ST2 (sST2) in CRSwNP patients and their potential for predicting CRSwNP endotypes and postoperative recurrence. Methods. The present study recruited 149 CRSwNP patients, 80 of whom were noneosinophilic (neCRSwNP) and 69 eosinophilic (eCRSwNP), as well as 60 healthy controls (HCs). Serum samples were collected from all participants, and sST2 and IL-33 concentrations were measured using ELISA. Multivariate analysis, receiver operating characteristic (ROC) curves, and Kaplan-Meier curves were used to evaluate the value of serum sST2 and IL-33 levels in distinguishing CRSwNP endotypes and predicting postoperative recurrence. Results. The levels of serum sST2 and IL-33 in CRSwNP patients were significantly higher than those in HCs, especially in the eCRSwNP group. Increased sST2 and IL-33 levels were associated with eosinophil counts and percentages in both tissue and blood. Multivariate regression and ROC curve analysis showed that serum sST2 and IL-33 exhibited potential for distinguishing CRSwNP endotypes, and the combination of serum IL-33 and sST2 showed even more predictive power. Finally, 124 CRSwNP patients completed the entire 3-year follow-up. Multivariate analysis and Kaplan-Meier curves showed that serum sST2 and IL-33 levels were associated with recurrence; serum sST2 and IL-33 each exhibited potential for predicting postoperative recurrence, and combining serum sST2 and IL-33 exhibited better accuracy and practicability. Conclusion. Our results suggested that serum sST2 and IL-33 levels were upregulated in CRSwNP patients and related to the degree of mucosal eosinophil infiltration and postoperative recurrence. Serum sST2 and IL-33 might serve as objective biomarkers for distinguishing phenotypes and predicting recurrence in CRSwNP, and their combined use outperformed either marker alone.

Multiple-Cytokine Profiling: A Novel Method for Early Prediction of the Efficacy of Sublingual Immunotherapy in Allergic Rhinitis Patients

Background

Methods

Results

Conclusion

Serum Soluble ST2 Correlated with Symptom Severity and Clinical Response of Sublingual Immunotherapy for House Dust Mite-Induced Allergic Rhinitis Patients

Background

Suppressor of tumorigenicity 2 (ST2) is a key biomarker in inflammation and cardiovascular diseases, but limited data is available on its role in allergic rhinitis (AR).

Objective

The aim of this study is to explore the role of serum soluble ST2 (sST2) in evaluating disease severity and predicting the efficacy of sublingual immunotherapy (SLIT) in house dust mite- (HDM-) induced AR patients.

Methods

Eighty healthy controls (HC group) and 160 HDM-induced AR patients, including 40 mild patients (MAR group) and 120 moderate-severe patients (MSAR group), were recruited in this study. Serum was collected from all participants and levels of sST2 were determined by ELISA and the relationship between sST2 levels and disease severity was assessed. In the MSAR group, 109 patients received 3 years of SLIT, and the relationship between serum levels of sST2 and efficacy of SLIT was exampled.

Results

Serum sST2 levels were increased in HDM-induced AR patients compared to the HC group (P < 0.001), and the concentrations were higher in the MSAR group than in the MAR group and HC group (all P < 0.05). Moreover, sST2 levels positively correlated with the total nasal symptom score (TNSS), visual analogue scale (VAS), and specific IgE levels (P < 0.05). Seventy-eight MSAR patients accomplished SLIT, and they were divided into an effective group (n = 40) and an ineffective group (n = 38). The serum sST2 levels in the effective group were lower than those in the ineffective group (P < 0.001). In addition, patients in the effective group levels exhibited significantly lower sST2 levels post-SLIT than pre-SLIT (P < 0.001), but no statistic difference was observed in the ineffective group (P > 0.05). Receiver operating characteristic (ROC) curve showed promising accuracy for predicting clinical efficacy of SLIT in AR patients (area under the curve = 0.839, P < 0.001).

Conclusion

Serum sST2 is a potential biomarker for assessing disease severity and may serve as a sensitive biomarker for predicting the therapeutic response of SLIT in HDM-induced AR patients.

Pet ownership in pregnancy and methylation pattern in cord blood

Having pets in the house during the first years of life has been shown to protect against allergies. However, the result of different studies is heterogeneous. The aim of this study was to evaluate the methylation pattern in cord blood in relation to pet ownership during pregnancy.We investigated the methylation patterns of 96 cord blood samples, participants of the Epigenetic Hallmark of Maternal Atopy and Diet-ELMA project, born to mothers who either owned pets (n = 32) or did not own pets (n = 64) during their pregnancy. DNA from cord blood was analysed using the Infinium methylation EPIC. For statistical analysis, RnBeads software was applied.We found 113 differentially methylated sites (DMs) in the covariate-adjusted analysis (FDR p < 0.05), with small methylation differences. The top DMs were associated with genes: UBA7, THRAP3, GTDC1, PDE8A and SBK2. In the regional analysis, two promoter regions presented with significance: RN7SL621P and RNU6-211P. Cis-regulatory element analysis revealed significant associations with several immune-related pathways, such as regulation of IL18, Toll signalling, IL6 and complement.We conclude that pet exposure during pregnancy causes subtle but significant changes in methylation patterns in cord blood, which are reflected in the biological processes governing both innate and adaptive immune responses.