Hsieh LY, Chiang AWT, Duong LD, et al. - This study was sought to use proteomics and primary cell as a novel approach to ascertain relevant pro-fibrotic factors. Researchers applied primary esophageal eosinophilic esophagitis (EoE) and normal fibroblasts, their derivative extracellular matrixes (ECMs), an approach of fibroblast culture on autologous vs opposing ECM, and proteomics to evaluate EoE ECM proteins that dysregulate cellular function. This study’s findings demonstrated that EoE fibroblasts secrete a unique ECM proteome that reflects their in vivo state and induces collagen I and α-smooth muscle actin protein expression from normal fibroblasts. In EoE, thrombospondin-1 is a previously unappreciated pro-fibrotic molecule.