Novel Noninvasive Biomarker for Eosinophilic Esophagitis (EoE)

Rationale: , The field of EoE research has expanded greatly in the understanding of disease pathogenesis including esophageal fibrosis; however, there has been a significant delay in identifying reliable predictive EoE specific non-invasive biomarkers. Herein, we propose a panel of noninvasive biomarkers for disease progression and diagnosis.

Methods: , A flowcytometer analysis to detect CD274⁺ and CD274^- eosinophil subsets and qPCR analysis to detect mRNA levels of IL-18Rα, CD274 (PDL1), VIP, CD101 in normal and EoE patients blood and biopsies.

Results: We recently discovered two eosinophil subtypes in the blood of normal and EoE patients that will be identified by CD274⁺ and CD274^-. The CD274⁺ eosinophil increases in EoE patients as disease progresses and most eosinophil accumulated in esophageal biopsies of EoE patients are CD274⁺. In addition, we found that mRNA levels of IL-18Rα, CD274 (PDL1), VIP (eosinophil chemoattractant), CD101 (T regulatory cells suppressor) significantly increases in blood and esophageal biopsies of EoE patients compare to normal and GERD patients.  Additionally, the mRNA levels of IL-18Rα, CD274, VIP, CD101 correlates well with blood eosinophilia that significantly reduces in improved EoE patients.

Conclusions: We first time show eosinophil two subset and only CD274⁺ eosinophil increases in the blood of EoE patients. Furthermore, blood and tissue mRNA levels of IL-18Rα, CD274, VIP, CD101 increases and correlates with the eosinophils of blood and biopsies, respectively. Taken together, induced CD274⁺ eosinophils and indicated panel of molecules will be the novel noninvasive biomarkers for EoE, which even differentiate EoE from GERD.