Application of a degradable thin film to modulate perfusion to post-autotransplantation airways in rats.

Objective: Recipients of lung transplants experience the lowest long-term survival among all solid-organ transplant recipients. Airway complications contribute significantly to morbidity and mortality post-lung transplant and may be driven by airway devascularization inherent to procurement and implantation of the lungs. We studied application of biodegradable, nanofiber-based thin films to devascularized autotransplanted airways to mitigate airway ischemia.

Methods: We used a rat tracheal autotransplantation model that replicates airway ischemia. Rats were divided into an operated control group (n = 18) and a treatment group (n = 12) receiving an electrospun film composed of randomly aligned polydioxanone (PDO) nanofibers applied to the circumferential surface of the transplanted trachea. Airway perfusion was assessed via laser speckle contrast analysis at 0, 3, and 10 days. Differences in perfusion units were calculated between the nontransplanted and transplanted segments of the trachea. Multimodal analysis of angiogenesis in tracheal autografts included immunoassay profiling for proangiogenic cytokines, histologic injury grading, and speckle angiography.

Results: Qualitative and quantitative perfusion differences were demonstrated at days 0, 3, and 10. Nanofiber-based, PDO thin films significantly improved perfusion in the transplanted segment of trachea ( < .05). Histologic injury scoring was significantly worse in the operated controls compared with the treatment group ( < .01). Immunoassays demonstrated increased expression of vascular cell adhesion molecule 1 in the treatment group ( < .05).

Conclusions: Application of a nanofiber-based, PDO thin film induced a local tissue response that improved perfusion and histologic injury scoring of the transplanted airway in an autotransplant model of airway devascularization. Immune multiplexing suggests local inflammatory responses may drive angiogenesis.