Decellularized Lung Scaffolds for Bioengineered Organs

Abstract: Background: Lung transplantation is a treatment provided to patients in terminal respiratory diseases. While opportunities for organ transplantation are somewhat limited, the list of patients awaiting donation is increasing. Therefore, new strategies are required to increase the availability of organs. The development of bioengineered lungs is one potential therapeutic alternative to functional organ transplantation. Intensive research, carried out by several groups, has explored the possibility of using tissue engineering to produce completely decellularized organs.
Material/Methods: This study aimed to demonstrate in an experimental animal model the decellularization process of lungs in order to prepare scaffolds for artificial recreation of organs. For the successful creation of a bioengineered lung, it is necessary that the organ remains viable and contains a functional architecture that allows adequate ventilation, perfusion, and gas exchange.
Results: Cells and nuclear material were removed during the decellularization process, but the architecture of the alveolar septum remained unchanged. An scanning electron microscope study confirmed that the alveolar cells, red blood cells, and cellular proteins previously present in the native lung were absent in the decellularized structure. Quantitative trials showed that collagen had been retained in the extracellular matrix, while elastin was partially exhausted. High-resolution micro-computed tomography revealed that the lung architecture, arterial weft, and microcirculation remained intact.
Conclusions: Decellularization is part of the bioengineering process, and various ionic, nonionic, and zwitterionic detergents have been used during decellularization. The variety of methods used in these studies also reinforces the need for a standard decellularization protocol that could advance the development of bioengineered organs.

Keywords: Bioengineering, Tissue Scaffolds