TH2 cell compensatory effect following benralizumab treatment for eosinophilic gastritis.

BACKGROUND: Eosinophil accumulation is a main feature of eosinophilic gastritis (EoG) and is associated with its histologic diagnosis and pathology. However, a recent clinical trial has demonstrated that EoG endoscopic, noneosinophil histologic, and clinical features remain persistent despite complete eosinophil depletion. OBJECTIVE: Our aim was to examine gastric T-cell composition and associated cytokine levels of patients with EoG following benralizumab-induced eosinophil depletion versus following administration of placebo. METHODS: A cohort of subjects with EoG from a subset of subjects who participated in a recent phase 2 benralizumab trial was treated for 12 weeks with administration of 3 doses of benralizumab (anti-IL-5 receptor α antibody [n = 5]) or placebo (n = 4). Single-cell suspensions obtained by gastric biopsy were stimulated with phorbol 12,13-dibutyrate and ionomycin in the presence of brefeldin A and monensin. Harvested cells were fixed, stained, and analyzed by flow cytometry to examine T-cell populations and associated cytokines. RESULTS: Following benralizumab treatment but not placebo, blood and gastric eosinophil levels decreased 16-fold and 10-fold, respectively. Whereas histologic score and features were significantly decreased, no change was observed in endoscopic score and features. Following complete eosinophil depletion with benralizumab, gastric TH2 cell levels were 3-fold higher than the levels in the patients with EoG who were given placebo; and the levels of associated type 2 cytokine production of IL-4, IL-5, and IL-13 in the benralizumab-treated patients were, respectively, 4-, 5.5-, and 2.5-fold, higher than those in the placebo-treated patients. CONCLUSION: We have identified a putative positive feedback loop whereby eosinophil depletion results in a paradoxic increase in levels of TH2 cells and derived cytokines; this finding suggests an explanation for the limited success of eosinophil depletion as monotherapy in eosinophil-associated gastrointestinal disorders.

Transnasal Endoscopy Acquires Esophageal Biopsies Adequate for Comprehensive Pathology Evaluation in Patients With Eosinophilic Esophagitis.

BACKGROUND: Transnasal endoscopy (TNE) does not require general anesthesia, an attractive characteristic for monitoring eosinophilic esophagitis (EoE). We evaluated the adequacy of TNE-obtained esophageal biopsies using the EoE Histology Scoring System (EoEHSS). METHODS: The Cincinnati Center for Eosinophilic Disorders database was searched for esophageal biopsies obtained by the same endoscopist, using either TNE or conventional endoscopy (CE). Whole-slide biopsy images were evaluated. The Mann-Whitney test was used for median (interquartile range) values and Fisher exact test for categorical variables. P ≤ .05 was considered significant. RESULTS: Median age (P = .82) or height (P = .83) did not differ between TNE (n = 17) and CE (n = 17) groups. Although median largest piece size (mm2) differed between the groups (TNE: 0.59 (0.45, 0.86), CE: 2.24 (1.09, 2.82), P < .001), all 8 EoEHSS features were evaluated in each group; only 1 feature (lamina propria fibrosis) was missing in both groups (TNE: 19/34, CE: 11/34, P = .09). The median peak eosinophil count/high-power field differed (TNE: 3 (0, 29), CE: 16 (1, 66), P = .03), but overall grade (TNE: 0.17 (0.10, 0.29), CE: 0.22 (0.14, 0.46), P = .12), stage (TNE: 0.14 (0.10, 0.24), CE: 0.20 (0.10, 0.43), P = .15), and non-eosinophil-related individual EoEHSS scores did not differ. CONCLUSIONS: TNE- and CE-obtained esophageal biopsies are similarly sufficient for evaluation of key pathological features in EoE.

Pooled Phase 2 and 3 Efficacy and Safety Data on Budesonide Oral Suspension in Adolescents with Eosinophilic Esophagitis.

OBJECTIVES: The objective of this study was to evaluate the efficacy and safety of budesonide oral suspension (BOS) in adolescents with eosinophilic esophagitis (EoE). METHODS: This post hoc analysis pooled data from two 12-week, randomized, double-blind, placebo-controlled studies of BOS 2.0 mg twice daily (b.i.d.) (phase 2, NCT01642212; phase 3, NCT02605837) in patients aged 11-17 years with EoE and dysphagia. Efficacy endpoints included histologic (≤6, ≤1, and <15 eosinophils per high-power field [eos/hpf]), dysphagia symptom (≥30% reduction in Dysphagia Symptom Questionnaire [DSQ] scores from baseline), and clinicopathologic (≤6 eos/hpf and ≥30% reduction in DSQ scores from baseline) responses at week 12. Change from baseline to week 12 in peak eosinophil counts, DSQ scores, EoE Histology Scoring System (EoEHSS) grade (severity) and stage (extent) total score ratios (TSRs), and total EoE Endoscopic Reference Scores (EREFS) were assessed. Safety outcomes were also examined. RESULTS: Overall, 76 adolescents were included (BOS, n = 45; placebo, n = 31). Significantly more patients who received BOS than placebo achieved histologic responses (≤6 eos/hpf: 46.7% vs 6.5%; ≤1 eos/hpf: 42.2% vs 0.0%; <15 eos/hpf: 53.3% vs 9.7%; P < 0.001) and a clinicopathologic response (31.1% vs 3.2%; P = 0.003) at week 12. More BOS-treated than placebo-treated patients achieved a dysphagia symptom response at week 12 (68.9% vs 58.1%; not statistically significant P = 0.314). BOS-treated patients had significantly greater reductions in EoEHSS grade and stage TSRs ( P < 0.001) and total EREFS ( P = 0.021) from baseline to week 12 than placebo-treated patients. BOS was well tolerated, with no clinically meaningful differences in adverse events versus placebo. CONCLUSIONS: BOS 2.0 mg b.i.d. significantly improved most efficacy outcomes in adolescents with EoE versus placebo.

Esophageal Epithelium and Lamina Propria Are Unevenly Involved in Eosinophilic Esophagitis.

BACKGROUND & AIMS: The nature of the involvement of esophageal tissue in eosinophilic esophagitis (EoE) is unclear. We estimated the intrabiopsy site agreements of the EoE Histologic Scoring System (EoEHSS) scores for the grade (degree) and stage (extent) of involvement of the esophageal epithelial and lamina propria and examined if the EoE activity status influenced the intrabiopsy site agreement. METHODS: Demographic, clinical, and EoEHSS scores collected as part of the prospective Outcome Measures for Eosinophilic Gastrointestinal Diseases Across Ages study were analyzed. A weighted Cohen's kappa agreement coefficient (k) was used to calculate the pairwise agreements for proximal:distal, proximal:middle, and middle:distal esophageal biopsy sites, separately for grade and stage scores, for each of the 8 components of EoEHSS. A k > 0.75 was considered uniform involvement. Inactive EoE was defined as fewer than 15 eosinophils per high-powered field. RESULTS: EoEHSS scores from 1263 esophageal biopsy specimens were analyzed. The k for the stage of involvement of the dilated intercellular spaces across all 3 sites in inactive EoE was consistently greater than 0.75 (range, 0.87-0.99). The k for lamina propria fibrosis was greater than 0.75 across some of the biopsy sites but not across all 3. Otherwise, the k for all other features, for both grade and stage, irrespective of the disease activity status, was 0.75 or less (range, 0.00-0.74). CONCLUSIONS: Except for the extent of involvement of dilated intercellular spaces in inactive EoE, the remaining epithelial features and lamina propria are involved unevenly across biopsy sites in EoE, irrespective of the disease activity status. This study enhances our understanding of the effects of EoE on esophageal tissue pathology.

Local type 2 immunity in eosinophilic gastritis.

BACKGROUND: Eosinophilic gastritis (EoG) associates with type 2 immunity. However, the type 2 cytokine cellular source, gastric T-cell composition, and gastric T-cell relationship (or relationships) with disease pathology remain understudied. OBJECTIVE: We defined gastric T-cell populations and their association with histologic and endoscopic EoG pathology. METHODS: Gastric biopsy samples (n = 6 EoG, n = 7 control) were subjected to histologic, endoscopic, and flow cytometry analyses. In a complementary cohort (n = 83 EoG), IL4, IL5, and IL13 mRNA levels were correlated with EoG pathologic parameters. RESULTS: Gastric biopsy samples contained CD3+ T cells that were mainly CD8+; the CD8/CD4 ratio was comparable in EoG and control biopsy samples (5.7 ± 3.0 and 4.3 ± 0.6, respectively; P = .28). Gastric regulatory T (CD3+CD4+FOXP3+) and TH2 (CD3+CD4+GATA3+) cell levels were increased in EoG versus controls (2-fold, P < .05 and 10-fold, P < .001, respectively) and correlated with gastric eosinophil levels (r = 0.63, P < .05 and r = 0.85, P < .001, respectively), endoscopic pathology (r = 0.56, P < .01; r = 0.84, P < .001, respectively), and histopathology (r = 0.72, P < .01; r = 0.82, P < .01, respectively). Cytokine-positive, most notably IL-4+, TH2 cell levels strongly correlated with histologic and endoscopic scores (r = 0.82, P < .0001 and r = 0.78, P < .0001, respectively). In an independent EoG cohort (n = 83), bulk gastric IL4, IL5, and IL13 mRNA levels correlated with histologic score (r = 0.22, P < .005; r = 0.54, P < .0001; and r = 0.36, P < .0001, respectively) and endoscopic score (r = 0.27, P < .001; r = 0.40, P < .0001; and r = 0.35, P < .0001, respectively). CONCLUSIONS: EoG is a TH2 cell-associated disease featuring increased gastric type 2 cytokine-producing CD3+CD4+GATA3+TH2 cells that strongly correlate with disease pathologies.

Molecular analysis of duodenal eosinophilia.

BACKGROUND: Eosinophilic duodenitis (EoD), characterized by nonspecific gastrointestinal symptoms and increased numbers of duodenal eosinophils, may be in the eosinophilic gastrointestinal disease spectrum. However, diagnostic thresholds and pathogenic processes of duodenal tissue eosinophilia are inadequately characterized. OBJECTIVE: We aimed to define an EoD transcriptome and pathologic pathways. METHODS: RNA sequencing and histologic features of human duodenal biopsy samples were analyzed as a function of duodenal eosinophils levels. For analyses, we defined EoD as more than 52 peak eosinophils/hpf (n = 8), duodenal eosinophilia as 30 to 52 eosinophils/hpf (n = 11), and normal controls as fewer than 30 eosinophils/hpf (n = 8). Associations between gene expression and histologic features were analyzed with Spearman correlation. RESULTS: We identified 382 differentially expressed genes (EoD transcriptome) between EoD and normal controls (>2-fold change [adjusted P < .05]). The EoD transcriptome distinguished EoD from controls (duodenal eosinophilia and normal controls). The duodenal eosinophil count was correlated with a distinct EoD transcriptome when 50 to 60 peak eosinophils/hpf were present. The EoD transcriptome was enriched in genes involved in IL-4/IL-13 signaling, mast cells, and myeloid progenitor cells. Among duodenal histologic features, lamina propria eosinophil sheets was the most associated with transcriptomic changes (r = 0.66; P < .01). EoD gene signatures were shared with eosinophilic esophagitis and eosinophilic gastritis but not with eosinophilic colitis or celiac disease. CONCLUSION: We have identified an EoD transcriptomic signature that emerges at 50 to 60 peak eosinophils/hpf and established EoD as part of a spectrum of upper eosinophilic gastrointestinal disorder associated with type 2 immunity and distinct from eosinophilic colitis and celiac disease. These findings provide a basis for improving diagnosis and treatment.

Mucosal Microbiota Associated With Eosinophilic Esophagitis and Eosinophilic Gastritis.

OBJECTIVE: The aim of the study was to determine the mucosal microbiota associated with eosinophilic esophagitis (EoE) and eosinophilic gastritis (EoG) in a geographically diverse cohort of patients compared to controls. METHODS: We conducted a prospective study of individuals with eosinophilic gastrointestinal disease (EGID) in the Consortium of Eosinophilic Gastrointestinal Disease Researchers, including pediatric and adult tertiary care centers. Eligible individuals had clinical data, mucosal biopsies, and stool collected. Total bacterial load was determined from mucosal biopsy samples by quantitative polymerase chain reaction (PCR). Community composition was determined by small subunit rRNA gene amplicons. RESULTS: One hundred thirty-nine mucosal biopsies were evaluated corresponding to 93 EoE, 17 EoG, and 29 control specimens (18 esophageal) from 10 sites across the United States. Dominant community members across disease activity differed significantly. When comparing EoE and EoG with controls, the dominant taxa in individuals with EGIDs was increased ( Streptococcus in esophagus; Prevotella in stomach). Specific taxa were associated with active disease for both EoE ( Streptococcus , Gemella ) and EoG ( Leptotrichia ), although highly individualized communities likely impacted statistical testing. Alpha diversity metrics were similar across groups, but with high variability among individuals. Stool analyses did not correlate with bacterial communities found in mucosal biopsy samples and was similar in patients and controls. CONCLUSIONS: Dominant community members ( Streptococcus for EoE, Prevotella for EoG) were different in the mucosal biopsies but not stool of individuals with EGIDs compared to controls; taxa associated with EGIDs were highly variable across individuals. Further study is needed to determine if therapeutic interventions contribute to the observed community differences.

Prospective Endoscopic Activity Assessment for Eosinophilic Gastritis in a Multisite Cohort.

INTRODUCTION: Eosinophilic gastritis (EG) is a chronic inflammatory disease of the stomach characterized by eosinophil-predominant gastric mucosal inflammation and gastrointestinal symptoms. The aim of this study was to prospectively evaluate endoscopic features in a large series of children and adults with EG to better understand the endoscopic manifestations and develop a standardized instrument for investigations. METHODS: Data were prospectively collected as part of the Consortium for Eosinophilic Gastrointestinal Disease Researchers, a national collaborative network. Endoscopic features were prospectively recorded using a system specifically developed for EG, the EG Endoscopic Reference System (EG-REFS). Correlations were made between EG-REFS and clinical and histologic features. RESULTS: Of 98 patients with EG, 65 underwent assessments using EG-REFS. The most common findings were erythema (72%), raised lesions (49%), erosions (46%), and granularity (35%); only 8% of patients with active histology (≥30 eosinophils/high-power field) exhibited no endoscopic findings. A strong correlation between EG-REFS scores and physician global assessment of endoscopy severity was demonstrated (Spearman r = 0.84, P < 0.0001). The overall score and specific components of EG-REFS were more common in the antrum than in the fundus or body. EG-REFS severity was significantly correlated with active histology, defined by a threshold of ≥30 eosinophils/high-power field (P = 0.0002). DISCUSSION: Prospective application of EG-REFS identified gastric features with a strong correlation with physician global assessment of endoscopic activity in EG. Endoscopic features demonstrated greater severity in patients with active histology and a predilection for the gastric antrum. Further development of EG-REFS should improve its utility in clinical studies.

Development and Validation of Web-Based Tool to Predict Lamina Propria Fibrosis in Eosinophilic Esophagitis.

INTRODUCTION: Approximately half of esophageal biopsies from patients with eosinophilic esophagitis (EoE) contain inadequate lamina propria, making it impossible to determine the lamina propria fibrosis (LPF). This study aimed to develop and validate a web-based tool to predict LPF in esophageal biopsies with inadequate lamina propria. METHODS: Prospectively collected demographic and clinical data and scores for 7 relevant EoE histology scoring system epithelial features from patients with EoE participating in the Consortium of Eosinophilic Gastrointestinal Disease Researchers observational study were used to build the models. Using the least absolute shrinkage and selection operator method, variables strongly associated with LPF were identified. Logistic regression was used to develop models to predict grade and stage of LPF. The grade model was validated using an independent data set. RESULTS: Of 284 patients in the discovery data set, median age (quartiles) was 16 (8-31) years, 68.7% were male patients, and 93.4% were White. Age of the patient, basal zone hyperplasia, dyskeratotic epithelial cells, and surface epithelial alteration were associated with presence of LPF. The area under the receiver operating characteristic curve for the grade model was 0.84 (95% confidence interval: 0.80-0.89) and for stage model was 0.79 (95% confidence interval: 0.74-0.84). Our grade model had 82% accuracy in predicting the presence of LPF in an external validation data set. DISCUSSION: We developed parsimonious models (grade and stage) to predict presence of LPF in esophageal biopsies with inadequate lamina propria and validated our grade model. Our predictive models can be easily used in the clinical setting to include LPF in clinical decisions and determine its effect on treatment outcomes.

Budesonide Oral Suspension Improves Outcomes in Patients With Eosinophilic Esophagitis: Results from a Phase 3 Trial.

BACKGROUND & AIMS: Eosinophilic esophagitis (EoE) is a chronic, immune-mediated disease for which there is currently no pharmacologic therapy approved by the US Food and Drug Administration. METHODS: In this double-blind, placebo-controlled, phase 3 trial, patients 11-55 years of age with EoE and dysphagia were randomized 2:1 to receive budesonide oral suspension (BOS) 2.0 mg twice daily or placebo for 12 weeks at academic or community care practices. Co-primary endpoints were the proportion of stringent histologic responders (≤6 eosinophils/high-power field) or dysphagia symptom responders (≥30% reduction in Dysphagia Symptom Questionnaire [DSQ] score) over 12 weeks. Changes in DSQ score (key secondary endpoint) and EoE Endoscopic Reference Score (EREFS) (secondary endpoint) from baseline to week 12, and safety parameters were examined. RESULTS: Overall, 318 patients (BOS, n = 213; placebo, n = 105) were randomized and received ≥1 dose of study treatment. More BOS-treated than placebo-treated patients achieved a stringent histologic response (53.1% vs 1.0%; Δ52% [95% confidence interval (CI), 43.3%-59.1%]; P < .001) or symptom response (52.6% vs 39.1%; Δ13% [95% CI, 1.6%-24.3%]; P = .024) over 12 weeks. BOS-treated patients also had greater improvements in least-squares mean DSQ scores and EREFS over 12 weeks than placebo-treated patients: DSQ, -13.0 (SEM 1.2) vs -9.1 (SEM 1.5) (Δ-3.9 [95% CI, -7.1 to -0.8]; P = .015); EREFS, -4.0 (SEM 0.3) vs -2.2 (SEM 0.4) (Δ-1.8 [95% CI, -2.6 to -1.1]; P < .001). BOS was well tolerated; most adverse events were mild or moderate in severity. CONCLUSIONS: In patients with EoE, BOS 2.0 mg twice daily was superior to placebo in improving histologic, symptomatic, and endoscopic outcomes over 12 weeks. BOS 2.0 mg twice daily was well tolerated. ClinicalTrials.gov number: NCT02605837.

Long-Lasting Dissociation of Esophageal Eosinophilia and Symptoms After Dilation in Adults With Eosinophilic Esophagitis.

BACKGROUND & AIMS: Esophageal dilation improves dysphagia but not inflammation in eosinophilic esophagitis (EoE) patients. We investigated if dilation modifies the association between symptoms and peak esophageal eosinophils per high-power field (eos/hpf). METHODS: Adults enrolled in a multisite prospective Consortium of Gastrointestinal Eosinophilic Disease Researchers Outcome Measures for Eosinophilic Gastrointestinal Diseases Across Ages observational study (NCT02523118) completed the symptom-based EoE activity index (EEsAI) patient-reported outcome instrument and underwent endoscopy with biopsy specimens. Patients were stratified based on dilation status as absent, performed 1 year or less before endoscopy, and performed more than 1 year before endoscopy. Assessments included Spearman correlations of the relationship between symptoms and eos/hpf and linear regression with EEsAI as the outcome, eos/hpf as predictor, and interaction for dilation and eos/hpf. RESULTS: Among 100 patients (n = 61 males; median age, 37 y), 15 and 40 patients underwent dilation 1 year or less and more than 1 year before index endoscopy, respectively. In nondilated patients, the association between eos/hpf and symptoms was moderate (ρ = 0.49; P < .001); for a 10-eos/hpf increase, the predicted EEsAI increased by 2.69 (P = .002). In patients dilated 1 or less and more than 1 year before index endoscopy, this association was abolished (ρ = -0.38; P = .157 for ≤1 y and ρ = 0.02; P = .883 >1 y); for a 10-eos/hpf increase, the predicted EEsAI changed by -1.64 (P = .183) and 0.78 (P = .494), respectively. Dilation modified the association between symptoms and eos/hpf (P = .005 and P = .187 for interaction terms of eos/hpf and dilation 1 or less years before and more than 1 year before index endoscopy, respectively). CONCLUSIONS: In nondilated EoE adults, eos/hpf correlate modestly with symptoms; this correlation was no longer appreciated in dilated patients, and the dilation effects lasted longer than 1 year. Dilation status should be considered in studies evaluating EoE treatment and for clinical follow-up evaluation.

Desmoplakin and periplakin genetically and functionally contribute to eosinophilic esophagitis.

Eosinophilic esophagitis (EoE) is a chronic allergic inflammatory disease with a complex underlying genetic etiology. Herein, we conduct whole-exome sequencing of a multigeneration EoE pedigree (discovery set) and 61 additional multiplex families with EoE (replication set). A series of rare, heterozygous, missense variants are identified in the genes encoding the desmosome-associated proteins DSP and PPL in 21% of the multiplex families. Esophageal biopsies from patients with these variants retain dilated intercellular spaces and decrease DSP and PPL expression even during disease remission. These variants affect barrier integrity, cell motility and RhoGTPase activity in esophageal epithelial cells and have increased susceptibility to calpain-14-mediated degradation. An acquired loss of esophageal DSP and PPL is present in non-familial EoE. Taken together, herein, we uncover a pathogenic role for desmosomal dysfunction in EoE, providing a deeper mechanistic understanding of tissue-specific allergic responses.

Eosinophilic Esophagitis Histology Remission Score: Significant Relations to Measures of Disease Activity and Symptoms.

OBJECTIVES: Eosinophilic esophagitis (EoE) is characterized by remissions and relapses. Guidelines defining remission do not exist and therefore remission is inconsistently identified. We sought to define histology remission in EoE. METHODS: Esophageal biopsies, obtained at the time the validated pediatric EoE symptoms scores v2.0 (PEESS v2.0) questionnaire was completed (N = 42), were scored using the validated EoE Histology Scoring System. An EoE Histology Remission Score (EoEHRS) was constructed and specified that in all esophageal sites sampled the peak eosinophil count was <15 per high power field (HPF); in addition, neither the total grade (severity of pathology) nor stage (extent of pathology) scores could exceed 3 (possible total maximum score for each was 24). Spearman correlation coefficients were generated for histology/symptom correlations; coefficient range 0.31 to 0.50 was considered moderate. RESULTS: EoE Histology Scoring System composite and individual feature scores from proximal and distal esophageal biopsies correlated moderately with PEESS v2.0 mean scores (0.48-0.36, P < 0.01), and with scores in the dysphagia (0.39-0.30, P ≤ 0.01), pain (0.48-0.34, P ≤ 0.01), and gastroesophageal reflux disease (0.51-0.32, P ≤ 0.01) domains. Biopsies that met full EoEHRS criteria had reduced biomarkers, specifically expression of the mast cell markers CPA3 and tryptase mRNA, and reduced eosinophil peroxidase deposition (P < 0.03), compared to those with nonremission scores. Subjects whose biopsies met EoEHRS remission criteria reported reduced symptoms for all domains except nausea and vomiting (P ≤ 0.01). CONCLUSIONS: The EoEHRS correlated with reduced biomarkers of disease activity and reduced symptoms, and therefore may be useful to inform clinical care and interstudy comparisons.

Molecular, endoscopic, histologic, and circulating biomarker-based diagnosis of eosinophilic gastritis: Multi-site study.

BACKGROUND: Eosinophilic gastritis (EG) is a clinicopathologic disorder with marked gastric eosinophilia and clinical symptoms. There is an unmet need among patients with EG for more precise diagnostic tools. OBJECTIVE: We aimed to develop tissue- and blood-based diagnostic platforms for EG. METHODS: Patients with EG and control subjects without EG were enrolled across 9 Consortium of Eosinophilic Gastrointestinal Disease Researchers-associated sites. An EG Diagnostic Panel (EGDP; gastric transcript subset) and EG blood biomarker panel (protein multiplex array) were analyzed. EGDP18 scores were derived from the expression of 18 highly dysregulated genes, and blood EG scores were derived from dysregulated cytokine/chemokine levels. RESULTS: Gastric biopsy specimens and blood samples from 185 subjects (patients with EG, n = 74; control subjects without EG, n = 111) were analyzed. The EGDP (1) identified patients with active EG (P < .0001, area under the curve ≥ 0.95), (2) effectively monitored disease activity in longitudinal samples (P = .0078), (3) highly correlated in same-patient samples (antrum vs body, r = 0.85, P < .0001), and (4) inversely correlated with gastric peak eosinophil levels (r = -0.83, P < .0001), periglandular circumferential collars (r = -0.73, P < .0001), and endoscopic nodularity (r = -0.45, P < .0001). For blood-based platforms, eotaxin-3, thymus and activation-regulated chemokine, IL-5, and thymic stromal lymphopoietin levels were significantly increased. Blood EG scores (1) distinguished patients with EG from control subjects without EG (P < .0001, area under the curve ≥ 0.91), (2) correlated with gastric eosinophil levels (plasma: r = 0.72, P = .0002; serum: r = 0.54, P = .0015), and (3) inversely correlated with EGDP18 scores (plasma: r = -0.64, P = .0015; serum: r = -0.46, P = .0084). Plasma eotaxin-3 levels strongly associated with gastric CCL26 expression (r = 0.81, P < .0001). CONCLUSION: We developed tissue- and blood-based platforms for assessment of EG and uncovered robust associations between specific gastric molecular profiles and histologic and endoscopic features, providing insight and clinical readiness tools for this emerging rare disease.

Identification of anoctamin 1 (ANO1) as a key driver of esophageal epithelial proliferation in eosinophilic esophagitis.

BACKGROUND: The pathology of eosinophilic esophagitis (EoE) is characterized by eosinophil-rich inflammation, basal zone hyperplasia (BZH), and dilated intercellular spaces, and the underlying processes that drive the pathologic manifestations of the disease remain largely unexplored. OBJECTIVE: We sought to investigate the involvement of the calcium-activated chloride channel anoctamin 1 (ANO1) in esophageal proliferation and the histopathologic features of EoE. METHODS: We examined mRNA and protein expression of ANO1 in esophageal biopsy samples from patients with EoE and in mice with EoE. We performed molecular and cellular analyses and ion transport assays on an in vitro esophageal epithelial 3-dimensional model system (EPC2-ALI) and murine models of EoE to define the relationship between expression and function of ANO1 and esophageal epithelial proliferation in patients with EoE. RESULTS: We observed increased ANO1 expression in esophageal biopsy samples from patients with EoE and in mice with EoE. ANO1 was expressed within the esophageal basal zone, and expression correlated positively with disease severity (eosinophils/high-power field) and BZH. Using an in vitro esophageal epithelial 3-dimensional model system revealed that ANO1 undergoes chromatin modification and rapid upregulation of expression after IL-13 stimulation, that ANO1 is the primary apical IL-13-induced Cl- transport mechanism within the esophageal epithelium, and that loss of ANO1-dependent Cl- transport abrogated esophageal epithelial proliferation. Mechanistically, ANO1-dependent regulation of basal cell proliferation was associated with modulation of TP63 expression and phosphorylated cyclin-dependent kinase 2 levels. CONCLUSIONS: These data identify a functional role for ANO1 in esophageal cell proliferation and BZH in patients with EoE and provide a rationale for pharmacologic intervention of ANO1 function in patients with EoE.

Single-cell RNA sequencing identifies inflammatory tissue T cells in eosinophilic esophagitis.

T cell heterogeneity is highly relevant to allergic disorders. We resolved the heterogeneity of human tissue CD3+ T cells during allergic inflammation, focusing on a tissue-specific allergic disease, eosinophilic esophagitis (EoE). We investigated 1088 single T cells derived from patients with a spectrum of disease activity. Eight disparate tissue T cell subtypes (designated T1-T8) were identified, with T7 and T8 enriched in the diseased tissue. The phenotypes of T7 and T8 resemble putative Treg (FOXP3+) and effector Th2-like (GATA3+) cells, respectively. Prodigious levels of IL-5 and IL-13 were confined to HPGDS+ CRTH2+IL-17RB+FFAR3+CD4+ T8 effector Th2 cells. EoE severity closely paralleled a lipid/fatty acid-induced activation node highlighted by the expression of the short-chain fatty acid receptor FFAR3. Ligands for FFAR3 induced Th2 cytokine production from human and murine T cells, including in an in vivo allergy model. Therefore, we elucidated the defining characteristics of tissue-residing CD3+ T cells in EoE, a specific enrichment of CD4+ Treg and effector Th2 cells, confinement of type 2 cytokine production to the CD4+ effector population, a highly likely role for FFAR3 in amplifying local Th2 responses in EoE, and a resource to further dissect tissue lymphocytes and allergic responses.

17ß-Estradiol protects the esophageal epithelium from IL-13-induced barrier dysfunction and remodeling.

BACKGROUND: The incidence of eosinophilic esophagitis (EoE) is greater in male than female subjects, and the underlying molecular basis for this sex bias remains unclear. OBJECTIVE: We sought to delineate the contribution of the sex hormone estrogen to the EoE phenotype and esophageal epithelial barrier function and remodeling. METHODS: We performed demographic and incidence analyses of EoE in male and female subjects from a single-center pediatric cohort. Estrogen-responsive gene expression analyses and estrogen receptor (ESR) immunofluorescence staining of esophageal biopsy specimens from patients with EoE and control subjects were performed. The effect of 17ß-estradiol (E2) on IL-13-induced signaling pathways, gene expression, and esophageal epithelial architecture and barrier function in a primary human esophageal keratinocyte cell (EPC2) culture system (EPC2-air-liquid interface) was examined. RESULTS: We observed a male predominance in patients with EoE. Analyses of RNA sequencing data sets revealed a significant dysregulation of the estrogen-responsive gene network and expression of ESR1 and ESR2 in esophageal biopsy specimens from patients with EoE compared with control subjects. IL-13 stimulation of EPC2-air-liquid interface cells led to altered cellular architecture with induced dilation of intercellular spaces and barrier dysfunction. Pretreatment of EPC2s with E2 prior to IL-13 exposure abrogated IL-13-induced architectural changes and esophageal barrier dysfunction. Mechanistically, E2-protective effects were dependent on ESR2 and associated with diminishing of IL-13-induced tyrosine kinase 2 and signal transducer and activator of transcription 6 phosphorylation and EoE-dysregulated gene expression. CONCLUSIONS: Estrogen-responsive genes are modified in patients with EoE compared with control subjects. E2 attenuated IL-13-induced architectural changes and esophageal epithelial barrier dysfunction through inhibition of the IL-13/tyrosine kinase 2/signal transducer and activator of transcription 6 pathway via ESR2-dependent process. Estrogen hormone signaling may protect against development of EoE in female subjects.

Updated International Consensus Diagnostic Criteria for Eosinophilic Esophagitis: Proceedings of the AGREE Conference.

BACKGROUND & AIMS: Over the last decade, clinical experiences and research studies raised concerns regarding use of proton pump inhibitors (PPIs) as part of the diagnostic strategy for eosinophilic esophagitis (EoE). We aimed to clarify the use of PPIs in the evaluation and treatment of children and adults with suspected EoE to develop updated international consensus criteria for EoE diagnosis. METHODS: A consensus conference was convened to address the issue of PPI use for esophageal eosinophilia using a process consistent with standards described in the Appraisal of Guidelines for Research and Evaluation II. Pediatric and adult physicians and researchers from gastroenterology, allergy, and pathology subspecialties representing 14 countries used online communications, teleconferences, and a face-to-face meeting to review the literature and clinical experiences. RESULTS: Substantial evidence documented that PPIs reduce esophageal eosinophilia in children, adolescents, and adults, with several mechanisms potentially explaining the treatment effect. Based on these findings, an updated diagnostic algorithm for EoE was developed, with removal of the PPI trial requirement. CONCLUSIONS: EoE should be diagnosed when there are symptoms of esophageal dysfunction and at least 15 eosinophils per high-power field (or approximately 60 eosinophils per mm2) on esophageal biopsy and after a comprehensive assessment of non-EoE disorders that could cause or potentially contribute to esophageal eosinophilia. The evidence suggests that PPIs are better classified as a treatment for esophageal eosinophilia that may be due to EoE than as a diagnostic criterion, and we have developed updated consensus criteria for EoE that reflect this change.

The antiprotease SPINK7 serves as an inhibitory checkpoint for esophageal epithelial inflammatory responses.

Loss of barrier integrity has an important role in eliciting type 2 immune responses, yet the molecular events that initiate and connect this with allergic inflammation remain unclear. We reveal an endogenous, homeostatic mechanism that controls barrier function and inflammatory responses in esophageal allergic inflammation. We show that a serine protease inhibitor, SPINK7 (serine peptidase inhibitor, kazal type 7), is part of the differentiation program of human esophageal epithelium and that SPINK7 depletion occurs in a human allergic, esophageal condition termed eosinophilic esophagitis. Experimental manipulation strategies reducing SPINK7 in an esophageal epithelial progenitor cell line and primary esophageal epithelial cells were sufficient to induce barrier dysfunction and transcriptional changes characterized by loss of cellular differentiation and altered gene expression known to stimulate allergic responses (for example, FLG and SPINK5). Epithelial silencing of SPINK7 promoted production of proinflammatory cytokines including thymic stromal lymphopoietin (TSLP). Loss of SPINK7 increased the activity of urokinase plasminogen-type activator (uPA), which in turn had the capacity to promote uPA receptor-dependent eosinophil activation. Treatment of epithelial cells with the broad-spectrum antiserine protease, α1 antitrypsin, reversed the pathologic features associated with SPINK7 silencing. The relevance of this pathway in vivo was supported by finding genetic epistasis between variants in TSLP and the uPA-encoding gene, PLAU We propose that the endogenous balance between SPINK7 and its target proteases is a key checkpoint in regulating mucosal differentiation, barrier function, and inflammatory responses and that protein replacement with antiproteases may be therapeutic for select allergic diseases.

Alignment of parent- and child-reported outcomes and histology in eosinophilic esophagitis across multiple CEGIR sites.

BACKGROUND: Patient-reported outcome metrics for eosinophilic esophagitis (EoE) have been developed and validated but not used in a multicenter pediatric population or systematically aligned with histology. OBJECTIVE: We sought to understand (1) the potential of caregiver report to predict patient self-reported symptoms and (2) the correlation of patient-reported outcome domains with histology. METHODS: Patients with EoE (n = 310) and their parents participating in the Consortium of Gastrointestinal Eosinophilic Disease Researchers (CEGIR) observational clinical trial were queried for baseline patient symptoms and quality of life (QOL) by using the Pediatric Eosinophilic Esophagitis Symptom Score, version 2 (PEESSv2.0), and the Pediatric QOL EoE module (PedsQL-EoE), and biopsy specimens were analyzed by using the EoE Histology Scoring System. RESULTS: PEESSv2.0 parental and child reports aligned across all domains (r = 0.68-0.73, P < .001). PedsQL-EoE reports correlated between parents and children across ages and multiple domains (r = 0.48-0.79, P < .001). There was a tight correlation between symptoms on PEESSv2.0 and their effects on QOL both on self-report and parental report (P < .001). Self-reported symptoms on PEESSv2.0 (positively) and PedsQL-EoE (inversely) showed a weak correlation with proximal, but not distal, peak eosinophil counts and features and architectural tissue changes on the EoE Histology Scoring System (P < .05). CONCLUSIONS: Parents of children with EoE aged 3 to 18 years accurately reflected their children's disease symptoms and QOL. Self- and parent-reported symptoms correlate with proximal esophageal histology. Our data suggest that parental report in young children can function as an adequate marker for self-reported symptoms and that self-reported symptoms can reflect changes in tissue histology in the proximal esophagus. These findings should be considered during clinical trials for drug development.