CXCL8 and gastroesophageal reflux disease: In contrast with this hypothesis, in which damage starts from surface and proceeds to the deep portions of the mucosa, a rat model for reflux esophagitis suggests that inflammation starts in the submucosa, with recruitment of T-lymphocytes, mediated by release of pro-inflammatory cytokines (IL-8) by the squamous epithelium, and successively proceeds toward the surface [8].