Perfusion‐Decellularization of Porcine Lung and Trachea for Respiratory Bioengineering

Abstract

Decellularization of native organs may provide an acellular tissue platform for organ regeneration. However, decellularization involves a trade-off between removal of immunogenic cellular elements and preservation of biomechanical integrity. We sought to develop a bioartificial scaffold for respiratory tissue engineering by decellularization of porcine lungs and trachea while preserving organ architecture and vasculature. Lung-trachea preparations from 25 German Landrace pigs were perfused in a modified Langendorff circuit and decellularized by an SDC (sodium deoxycholate)-based perfusion protocol. Decellularization was evaluated by histology and fluorescence microscopy, and residual DNA quantified spectrophotometrically and compared with controls. Airway compliance was evaluated by endotracheal intubation and mechanical ventilation to simulate physiological breathing-induced stretch. Structural integrity was evaluated by bronchoscopy and biomechanical stress/strain analysis by measuring passive tensile strength, all compared with controls. Decellularized lungs and trachea lacked intracellular components but retained specific collagen fibers and elastin. Quantitative DNA analysis demonstrated a significant reduction of DNA compared with controls (32.8 ± 12.4 μg DNA/mg tissue vs. 179.7 ± 35.8 μg DNA/mg tissue, P < 0.05). Lungs and trachea decellularized by our perfusion protocol demonstrated increased airway compliance but preserved biomechanical integrity as compared with native tissue. Whole porcine lungs-tracheae can be successfully decellularized to create an acellular scaffold that preserves extracellular matrix and retains structral integrity and three-dimensional architecture to provide a bioartifical platform for respiratory tissue engineering.

Biologic Scaffolds

“…Recently, a study involving the decellularization of 39 human hearts by perfusion of 1% SDS for 4 to 8 days showed that the decellularized organ promotes cardiocyte gene expression in implanted stem cells and allows the organization of cardiomyocytes into nascent muscle with electrical coupling (Sanchez et al 2015). A sodium deoxycholate-based perfusion protocol led to the decellularization of porcine lung and trachea, which maintained the structural and biomechanical integrity of the native tissue (Weymann et al 2015).…”

Comparative study of two perfusion routes with different flow in decellularization to harvest an optimal pulmonary scaffold for recellularization

“…Generation of bioartificial lungs and engineered tissue grafts and pulmonary bioprostheses are just a few examples of the proposed therapeutical approaches . Advances in pulmonary tissue engineering have enabled the development of pulmonary bioprostheses, based on seeding cells onto natural or synthetic three‐dimensional (3D) matrices or scaffolds.…”

“…4 Generation of bioartificial lungs and engineered tissue grafts and pulmonary bioprostheses are just a few examples of the proposed therapeutical approaches. 5 Advances in pulmonary tissue engineering have enabled the development of pulmonary bioprostheses, based on seeding cells onto natural or synthetic three-dimensional (3D) matrices or scaffolds. Therefore, scaffold biomaterial choice is the essential step, as the scaffold must be able to provide functional cell attachment niches and microenvironments resembling the native structural organization and promoting vascularization to ensure nutrients and oxygen supply into the host tissue.…”

“…6,7 Compared to some synthetic matrices, lung extracellular matrix (ECM), obtained after decellularization procedures, shows better preservation of the 3D-architecture and ECM microenvironment. 5 Lung ECM have appeared as promising pulmonary scaffolds due to their greater biocompatibility and biodegradability because of their properties are more similar to those of native pulmonary tissue. 8 These properties make lung ECM a suitable scaffold for cell reseeding and subsequent engraftment as a pulmonary bioprosthesis.…”

Development of a large‐volume human‐derived adipose acellular allogenic flap by perfusion decellularization

“…Decellularization of allogenic tissues has long been adopted to produce in large scale, off‐the‐shelf scaffolds (allografts) that are typically nonvascularized and limited in thickness and hence not effective in large‐volume reconstructions . Recently, it has been shown that immune‐compatible organs or large‐volume tissues (e.g., limbs, face, and others) can be obtained from human cadaveric donors or donor animals by sequential perfusion decellularization and recellularization . Perfusion decellularization/recellularization takes advantage of the native vascular network of the tissue to homogeneously penetrate it with decellularizing reagents and cultured cells, as well as to maintain a diffused blood supply to tissues after replantation.…”