A Translational Tissue Engineering Approach to Airway Reconstruction Leveraging Decellularized Meniscus and Cartilage Progenitor Cells

Abstract

Severe subglottic stenosis develops in over 20,000 infants per year and requires laryngotracheal reconstruction (LTR) to enlarge the airway by implanting autologous cartilage from a rib graft. However, young children often lack sufficiently sized costal cartilage resulting in increased donor site morbidity and operative time, as well as an elevated risk for airway restenosis necessitating revision surgery. To overcome these limitations, we have created a first-of-its-kind scaffold based on porcine meniscal cartilage decellularization (MEND) by selectively digesting the elastin and blood vessels uniquely present in the meniscus to create microchannels that support cellular re-invasion. Here we demonstrated that MEND can be fully recellularized in 3 days with ear-derived cartilage progenitor cells (eCPCs) and reaches structural and functional maturation suitable for implant within 3 weeks of chondrogenic differentiation, a time frame compatible with clinical translation, a first in airway tissue engineering. To further this therapy toward clinical translation, we validated the eCPCs-MEND grafts in a New Zealand white rabbit LTR model. Our results demonstrated airway expansion, graft re-epitheliazation, neocartilage formation, and integration with adjacent native laryngotracheal cartilage, notably at a higher degree than the standard of care of autologous costal cartilage. No instances of adverse events of extrusion, granulation, infection, or calcification were observed in any of the 38 rabbits of our 3 months study. These results demonstrate the feasibility of our translational tissue engineering approach to laryngotracheal reconstruction and could overcome the autograft-associated limitations in pediatric patients and a decrease the risk of invasive revision surgery.

A Pilot Study of Decellularized Cartilage for Laryngotracheal Reconstruction in a Neonatal Pig Model

“…There, in a LTR study of 38 rabbits, MEND expanded the airway and integrated with the adjacent cartilage, marked by an increase in glycosaminoglycans (GAGs) and neochondrification. 28 Although our previous study demonstrated the effectiveness of MEND as a graft for LTR, we are proposing to use MEND as an LTR graft in pediatric patients, and the rabbits of our previous study were adults. In fact, all animal studies published to test tissue engineered LTR grafts involved only adult animals, 29 which do not accurately recapitulate the complex growing environment of the pediatric airway or children undergoing LTR.…”

“…Our previous study successfully used MEND to engineer cartilage in vitro that mimicked the biochemical content and mechanical strength of the cricoid. There, in a LTR study of 38 rabbits, MEND expanded the airway and integrated with the adjacent cartilage, marked by an increase in glycosaminoglycans (GAGs) and neo‐chondrification 28 . Although our previous study demonstrated the effectiveness of MEND as a graft for LTR, we are proposing to use MEND as an LTR graft in pediatric patients, and the rabbits of our previous study were adults.…”