title: Eosinophilic esophagitis-linked calpain 14 is an IL-13-induced protease that mediates esophageal epithelial barrier impairment.
abstract: We recently identified a genome-wide genetic association of eosinophilic esophagitis (EoE) at 2p23 spanning the calpain 14 (CAPN14) gene, yet the causal mechanism has not been elucidated. We now show that recombinant CAPN14 cleaves a calpain-specific substrate and is inhibited by 4 classical calpain inhibitors: MDL-28170, acetyl-calpastatin, E-64, and PD151746. CAPN14 is specifically induced (>100-fold) in esophageal epithelium after IL-13 treatment. Epithelial cells overexpressing CAPN14 display impaired epithelial architecture, characterized by acantholysis, epidermal clefting, and epidermolysis. CAPN14 overexpression impairs epithelial barrier function, as demonstrated by decreased transepithelial resistance (2.1-fold) and increased FITC-dextran flux (2.6-fold). Epithelium with gene-silencedCAPN14demonstrates increased dilated intercellular spaces (5.5-fold) and less organized basal cell layering (1.5-fold) following IL-13 treatment. Finally, CAPN14 overexpression results in loss of desmoglein 1 (DSG1) expression, whereas the IL-13-induced loss of DSG1 is normalized byCAPN14gene silencing. Importantly, these findings were specific to CAPN14, as they were not observed with modulation of CAPN1 expression. These results, along with the potent induction ofCAPN14by IL-13 and genetic linkage of EoE to theCAPN14gene locus, demonstrate a molecular and cellular pathway that contributes to T helper type 2 responses in mucosal epithelium.
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Davis
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Emily M
authors.initials: EM
authors.lastname: Stucke
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: M Eyad
authors.initials: ME
authors.lastname: Khorki
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Vladislav A
authors.initials: VA
authors.lastname: Litosh
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Jeffrey K
authors.initials: JK
authors.lastname: Rymer
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Rochman
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Jared
authors.initials: J
authors.lastname: Travers
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.; Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Leah C
authors.initials: LC
authors.lastname: Kottyan
authors.affiliation: Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center (CCHMC), Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Marc E
authors.initials: ME
authors.lastname: Rothenberg