Regeneration of the esophagus using gastric acellular matrix: an experimental study in a rat model

Recently, tissue engineering of the autologous esophagus has been thought to provide a promising strategy for esophageal substitution. In this study, gastric acellular matrix (GAM) was used as a scaffold for regeneration of the esophagus in a rat model. Usage of GAM has an advantage that naturally derived extracellular matrix autograft can be prepared less invasively in a clinical setting. Twenty-seven F344 female rats were used as recipients. Patch defects created in the abdominal esophagus were replaced by GAM patch grafts. The rats were sacrificed 1 week to 18 months after implantation. The specimen was examined macroscopically as well as microscopically. 5'-Bromo-2'-deoxyuridine (BrdU) proliferation assay was performed in six rats that were sacrificed 1, 2, and 4 weeks after implantation. Twenty-four rats survived without complications. The graft site did not show esophageal stenosis or dilatation in any rat. Keratinized stratified squamous esophageal mucosa was regenerated in the entire graft 2 weeks after implantation. Regeneration of the muscle layer or lamina muscularis mucosae in the graft site was not observed even 18 months after implantation. Marked incorporation of BrdU was observed only in the mucosal layer but not in the muscle layer. GAM patch graft provided satisfactory mucosal regeneration of the esophagus without stenosis or dilatation, although muscle regeneration was still a future challenge.