A novel method for gene delivery and expression in esophageal epithelium with fibrin glues containing replication-deficient adenovirus vector

Background: Gene transfer to the esophageal epithelium holds the potential for the therapy of malignant as well as premalignant lesions in the upper gastrointestinal tract. Replication-deficient recombinant adenoviruses represent an efficient means of introducing genes in vivo into cells in a variety of organs. The majority of in vivo studies utilize direct submucosal injection for delivery of the viral vectors into the locoregional area of the gut; transferring genes into epithelial cells, however, is difficult because viruses are retained in the subepithelial space. To establish the efficient method for gene transfer into the epithelial cells, we have developed a multiluminal spray catheter that can be passed through the accessory channel of an endoscope, and we have evaluated the feasibility of fibrin glues as a vehicle of recombinant adenoviruses in a porcine model. Methods: The fibrinogen solution and the thrombion solution containing an E1/E3 deleted recombinant adenovirus expressing the bacterial lacZ gene (Ad-lacZ) were endoscopically sprayed on the porcine esophagus through the catheter attached to the dual-barrel syringe. Twenty-four hours after gene delivery, -galactosidase activity of the esophagus was determined under the microscope following X-gal staining. Results: The fibrin glue could be locally sprayed on the porcine esophagus by using the multichannel catheter through the endoscope. Attachment of the fibrin glue comtining Ad-lacZ caused strong -galactosidase staining on epithelial cells in the mucosal surface, but not in the basal cell layer. Conclusion: Endoscopic local delivery of recombinant adenoviruses in aerosolized fibrin glues through a multiluminal catheter could provide an optimal technique for gene transfer into epithelial cells in the mucosal surfece, which may have important implications for the treatment of human esophageal premalignant diseases.