MMPs-2 and-14 Are Elevated in Eosinophilic Esophagitis and Reduced Following Topical Corticosteroid Therapy

Objectives:Eosinophilic esophagitis (EoE) is a chronic, antigen-mediated disease in children and adults associated with substantial esophageal remodeling and fibrosis. The expression of the remodeling-associated matrix metalloproteinases (MMPs) has not been previously detailed in EoE.Methods:MMP-2 and -14 expression and cellular localization were assessed using real-time quantitative polymerase chain reaction and immunohistochemistry/immunofluorescence in EoE fibroblasts, active and inactive pediatric EoE biopsies, and nondiseased control biopsies. The effect of transforming growth factor (TGF)-1 treatment on MMP-2 expression in cultured esophageal epithelial (HET1A) cells was analyzed.Results:MMP-2 and -14 mRNA were expressed in EoE fibroblasts and biopsies. Proliferating epithelial cells produced MMP-14 more abundantly in EoE than in controls (P<0.001) and the degree of epithelial MMP-14 expression correlated positively with basal zone hyperplasia (r=0.65, P=0.002). EoE lamina propria had higher numbers of MMP-2- and -14-positive cells (906167 and 701 +/- 93cells/mm(2)) as compared with controls (258 +/- 93cells/mm(2), P<0.01 and 232 +/- 54cells/mm(2), P<0.01), and MMP-14 expression correlated with the severity of fibrosis. Following therapy with topical corticosteroids, MMP-14 and -2 were significantly diminished (P<0.01). TGF-1 increased the expression and secretion of MMP-2 from esophageal epithelial HET1A cells.Conclusions:MMP-2 and -14 are elevated in pediatric patients with EoE and significantly decrease following topical corticosteroid therapy. TGF-1 increases MMP-2 in esophageal epithelial cells. This alludes to previously unappreciated role for MMPs in EoE-associated esophageal remodeling and a potential positive feedback loop via TGF-1.