Prostaglandin and Cannabinoid Receptors in EoE

Prostaglandin D2 and E2 receptors, and components of the endocannabinoid system (cannabinoid receptors and endocannabinoid-metabolizing enzymes) are examined in mucosal esophageal biopsies and blood leukocytes from EoE patients (acute and in remission), individuals with gastroesophageal reflux and from individuals with no esophageal disease. Expression of these components are compared between all cohorts by polymerase chain reaction, Western blots, flow cytometry and immunohistochemical methods. EoE disease activity is evaluated by determining a symptom score and the number of eosinophils per high-power field (hpf) in histologic sections of mucosal biopsies. Additionally, an Endoscopic Reference Score (EREFS) is used. Disease activity is correlated with cannabinoid/prostaglandin D2 and E2 receptor expression. Blood is collected and immediately processed for flow cytometric experiments. Prostaglandins and endocannabinoids are measured in plasma and esophageal mucosal biopsy samples of all cohorts by mass spectrometry.