Up-Scaling Decellularization and Whole Organ Culture for Human Lung Regeneration

Abstract

Purpose Organ engineering is a theoretical therapy for organ failure. Whole organ matrices can be created by detergent perfusion, generating acellular scaffolds with the capacity for recellularization. This study aimed to up-scale this technology to clinically relevant porcine and human lungs, and to test their recellularization potential in biomimetic culture. Methods and Materials Rat, pig, and human lungs were perfused with detergent via the pulmonary artery at constant pressures, followed by washing. DNA was quantified by PicoGreen. Residual SDS was quantified by Stains-All assay. Soluble collagen, elastin, and glycosaminoglycans were quantified by colourimetric assays. Proteomic analysis by mass spectrometry (LC-MS/MS) generated spectral counts as a measure of abundance. Perfusion recellularization experiments of human lungs used standard organ culture techniques derived from rodent protocols. Results Rat lungs decellularized using (1) Sodium Dodecyl Sulfate (SDS), (2) Sodium deoxycholate, or (3) CHAPS showed loss of DNA but greatest preservation of ECM in SDS decellularized lungs. Histology and proteomics also confirmed greater matrix preservation in SDS lungs. The SDS-based decellularization protocol was up-scaled to porcine (n=7) and human (n=3) lungs with greater SDS concentration and perfusion pressures, and extended decellularization time. Removal of residual DNA and SDS was confirmed. Analysis of 10 areas from each decellularized lung showed intact ECM and lung architecture. Proteomics of human decellularized lungs further demonstrated matrix preservation. Recellularization of isolated lobar scaffolds used endothelial (HUVEC) and lung epithelial (SAEC) lines delivered to the appropriate organ compartment. Throughout biomimetic organ culture matrix integrity was maintained, while cell retention was observed by H&E and DAPI. Conclusions SDS decellularization can generate organ scaffolds with preserved ECM and architecture in whole porcine and human lungs. The results confirm clinical scale lung scaffolds can support recellularization for organ regeneration.