A Deficiency in the Cytokine TNFSF14/LIGHT Limits Inflammation and Remodeling in Murine Eosinophilic Esophagitis.

Eosinophilic esophagitis (EoE) is a chronic type 2 allergic disease, with esophageal tissue remodeling as the mechanism behind clinical dysphagia and strictures. IL-13 is thought to be a central driver of disease, but other inflammatory factors, such as IFNs and TNF superfamily members, have been hypothesized to play a role in disease pathogenesis. We recently found that the cytokine TNFSF14/LIGHT is upregulated in the esophagus of patients with EoE and that LIGHT promotes inflammatory activity in esophageal fibroblasts. However, the global effects of LIGHT on EoE pathogenesis in vivo remain unknown. We investigated the impact of a LIGHT deficiency in a murine model of EoE driven by house dust mite allergen. Chronic intranasal challenge with house dust mite promoted esophageal eosinophilia and increased CD4+ T cell numbers and IL-13 and CCL11 production in wild-type mice. Esophageal remodeling was reflected by submucosal collagen accumulation, increased muscle density, and greater numbers of fibroblasts. LIGHT-/- mice displayed normal esophageal eosinophilia, but exhibited reduced frequencies of CD4 T cells, IL-13 expression, submucosal collagen, and muscle density and a decrease in esophageal accumulation of fibroblasts. In vitro, LIGHT increased division of human esophageal fibroblasts and selectively enhanced IL-13-mediated expression of a subset of inflammatory and fibrotic genes. These results show that LIGHT contributes to various features of murine EoE, impacting the accumulation of CD4 T cells, IL-13 production, fibroblast proliferation, and esophagus remodeling. These findings suggest that LIGHT may be, to our knowledge, a novel therapeutic target for the treatment of EoE.