Tissue Engineer Transplantable Livers From Bio-Scaffolds

  • Tissue engineered liver using a pig model.
    Tissue engineered liver

    The images show acute transplantation of a reendothelialized bio-scaffold into a pig model to demonstrate patency. The bio-scaffold is placed into the surgical location and anastomosed to the native vasculature. It is then allowed to perfuse for 60 minutes before being removed and injected with contrast dye to demonstrate that the vasculature and capillaries remain open (patent). This demonstrates the ability of a reendothelialized bio-scaffold to be transplanted without thrombosis.

Tissue engineered liver

In collaboration with industry partner Miromatrix Medical Inc., Mayo researchers at the Artificial Liver and Liver Transplantation Laboratory are developing a protocol for producing transplantable human livers from decellularized pig livers.

This process involves all of the cells from a pig liver being removed using a continuous perfusion technique, which results in a decellularized bio-scaffold with the original architecture, mechanical properties and a vascular network of a normal liver. The bio-scaffold is recellularized with cell types necessary to restore normal function and blood flow.

The team has been working on the project for approximately three years. In 2014, accomplishments to date include transplanting reendothelialized bio-scaffolds and demonstrating normal blood flow in the biomatrix without clot formation after 60 minutes. The next steps include recellularizing the bio-scaffold with hepatocytes and bile duct cells and demonstrating function of fully recellularized grafts ex vivo and after transplantation.

The goal is to be the first team to create a bioengineered replacement liver enabling a large animal to recover in the absence of native function and survive three months with a normal lifestyle. This milestone is required before considering clinical application and Food and Drug Administration approval.