Late Breaking Abstract - Engraftment of autologous airway epithelial cells in the rabbit trachea

Epidermolysis bullosa (EB) is a group of rare, inherited genetic diseases characterised by epithelial fragility and blistering. Airway involvement in EB is rare, but affected patients experience a high burden of morbidity and mortality. EB airway disease involves granulation tissue formation and scarring of the larynx and trachea. As the disease progresses, airway stenosis (narrowing) necessitates a tracheostomy and can be lethal. <italic>LAMA3</italic> variants are common in this patient group, suggesting that <italic>LAMA3</italic> variants confer particular susceptibility to airway disease. We have shown that lentiviral expression of wildtype <italic>LAMA3A</italic> in cultured primary EB patient human airway basal epithelial cells corrects cell adhesion defects, but it remains unclear how to deliver transduced cells to airways. To explore stent-based epithelial cell delivery, we developed a surgical transplantation model through short segment tracheal resection and primary anastomosis in New Zealand white rabbits. We establish autologous epithelial cell cultures for each animal following a first surgical procedure. After transduction with a lentivirus encoding ZsGreen and luciferase for cell tracking, cells were seeded onto fibrin sheets and wrapped around bespoke 3D-printed soft elastomer composite tubular constructs. These constructs were delivered to the trachea in a second surgical procedure. Engraftment of transplanted cells was found after 4 or 10 days, demonstrating successful transfer of cells in 13/13 animals. However, after 28 days luciferase signal was significantly reduced, suggesting the loss of transplanted cells over time. Overall, our data provide initial evidence to support stent-based transplantation of epithelium to the trachea.