RESUMO
Organ scaffold bioengineering is currently limited by the inability to effectively repopulate the scaffold with appropriately distributed functional cells. We examined the feasibility of a decellularized liver scaffold to support the growth and function of multilineage allogenic cells derived from either adult or neonatal liver cells. Cell slurries from neonatal and adult rat livers containing hepatocytes, cholangiocytes, and endothelial cells were introduced into decellularized adult rat liver scaffolds via the bile duct. Recellularized grafts were perfused with cell growth medium through the portal vein for 7 days. Concurrently, the same cell slurries were incubated on culture dishes. Albumin levels were measured from graft perfusates and cell culture media. Immunofluorescent assays were used to verify the colocalization of cholangiocytes, hepatocytes, endothelial cells, and Kupffer cells in the recellularized grafts by using anti-CK7, anti-hepatocyte antigen, anti-CD34, and anti-CD68, respectively. More robust albumin production was detected in the perfusate of scaffolds recellularized with a neonatal liver cell slurry compared with those with an adult liver cell slurry. The perfusates from all recellularized grafts showed increasing albumin concentration over 7 days; higher levels were detected in the constructs compared with the cell culture. Scaffolds seeded with a neonatal liver cell slurry showed the presence of hepatocytes, cholangiocytes, endothelial cells, and Kupffer cells. Results demonstrated the superiority of neonatal allogenic cells over adult cells of the same origin, possibly because of their pluripotent behavior. Liver bio-scaffolds supported the growth of four different liver cell lines. Recellularized grafts exhibited preserved functionality as demonstrated by albumin production, and constructs seeded with a neonatal cell slurry demonstrated proliferation on Ki-67 assay, thus representing a promising model for a transplantable construct.
