MMP inhibition as a novel strategy for extracellular matrix preservation during whole liver decellularization

As the only reliable treatment option for end-stage liver diseases, conventional liver transplantation confronts major supply limitations. Accordingly, the decellularization of discarded livers to produce bioscaffolds that support recellularization with progenitor/stem cells has emerged as a promising translational medicine approach. The success of this approach will substantially be determined by the extent of extracellular matrix (ECM) preservation during the decellularization process. Here, we assumed that the matrix metalloproteinase (MMP) inhibition could reduce the ECM damage during the whole liver decellularization of an animal model using a perfusion-based system. We demonstrated that the application of doxycycline as an MMP inhibitor led to significantly higher preservation of collagen, glycosaminoglycans, and hepatic growth factor (HGF) contents, as well as mechanical and structural features, including tensile strength, fiber integrity, and porosity. Notably, produced bioscaffolds were biocompatible and efficiently supported cell viability and proliferation in vitro. We also indicated that produced bioscaffolds efficiently supported HepG2 cell function upon seeding onto liver ECM discs using albumin and urea assay. Additionally, MMP inhibitor pretreated decellularized livers were more durable in contact with collagenase digestion compared to control bioscaffolds in vitro. Using zymography, we confirmed the underlying mechanism that results in these promising effects is through the inhibition of MMP2 and MMP9. Overall, we demonstrated a novel method based on MMP inhibition to ameliorate the ECM structure and composition preservation during liver decellularization as a critical step in fabricating transplantable bioengineered livers.

Automated summary

As a promising approach in translational medicine, the decellularization of discarded livers to produce bioscaffolds that support recellularization has potential in overcoming the limitations of conventional liver transplantation. In this study, the researchers investigated the use of matrix metalloproteinase (MMP) inhibition to preserve the extracellular matrix (ECM) during liver decellularization. The results demonstrated that the application of an MMP inhibitor significantly improved the preservation of ECM components and mechanical properties of the bioscaffolds, which supported cell viability and function in vitro. The study also confirmed that the MMP inhibition led to the inhibition of MMP2 and MMP9, providing a novel method to enhance ECM preservation during liver decellularization.