Environmental Determinants and Non-Invasive Diagnosis of Eosinophilic Esophagitis

National Institute Of Allergy And Infectious Diseases

Investigators

Abstract

During the fiscal year, the project "Environmental Determinants and Non-Invasive Diagnosis of Eosinophilic Esophagitis" has progressed significantly in study initiation and exploring environmental factors contributing to eosinophilic esophagitis (EoE). This research evaluates the esophageal string test (EST) as a diagnostic tool and investigates environmental exposures linked to the rising prevalence of EoE, particularly in post-industrialized regions like the United States. The protocol has been initiated, and pre-screening of participants for enrollment is underway at both the National Institutes of Health (NIH) and Mali sites. Key personnel, including Dr. Moussa Dicko, have been trained in study procedures and sample collection. Community connections have been strengthened, facilitating the development of recruitment materials and resulting in multiple referrals of eligible patients. Significant advancements have been made in materials and methods. A novel polymerase chain reaction (PCR) technique has been developed to detect Helicobacter pylori from EST samples. Comprehensive microbiome data from skin, stool, and gastrointestinal tissues are being gathered. In the laboratory, environmental exposures such as per- and polyfluoroalkyl substances (PFAS) and food emulsifiers like polysorbate 80 (P80) are being investigated for their potential association with EoE risk. The project has yielded major findings, particularly concerning PFAS and P80. PFAS, including perfluoropentanoic acid (PFPeA), have been identified as possible contributors to increased EoE visit rates. Although PFPeA does not exhibit cytotoxic effects on esophageal epithelial cells, it may activate Th2 cytokine pathways, indicating a role in type 2 inflammation. Meanwhile, P80 has been found to cause cytotoxicity and impair barrier function in esophageal epithelial cells, even at low concentrations, underscoring the potential impact of processed food additives on esophageal health. Patient enrollment will continue at both the NIH Clinical Center and the partner site in Bamako, Mali. Laboratory experiments will further explore the transcriptomic effects of PFPeA and evaluate inflammatory responses following P80 exposure. These efforts are crucial for advancing our understanding of EoE development and informing preventive strategies, aligning with the broader goal of improving healthcare outcomes in the United States and beyond.