Purpose of review: Patients with liver cirrhosis often require liver transplantation, which remains the only effective treatment of the end-stage cirrhosis. Here we briefly summarize the current concepts in treatment of liver diseases based on the transplantation of intrahepatic liver cells, capable of repopulating the injured liver. These cells include hepatocytes, oval cells (bipotential intrahepatic progenitor cells), bone marrow hematopoietic and mesenchymal stem cells, and induced pluripotent stem (iPS) cells.
Recent findings: Although liver transplantation remains the only conventional treatment, liver cell transplantation is an experimental procedure which has been successfully used in clinical trials in patients with acute liver failure, chronic liver disease with end-stage cirrhosis. Extraordinary progress has been made in the field of hepatic progenitors and iPS. Liver precursor cells (oval cells) are recognized as bipotential precursor cells in the damaged liver. They can rapidly proliferate, change their cellular composition, and differentiate into hepatocytes and cholangiocytes to compensate for the cellular loss and maintain liver homeostasis in animal models of liver injury. Similarly, iPS are somatic cells obtained from patients and differentiated into hepatocytes in vitro. Future studies of iPS are designed to develop of specific conditions to expand and in vitro differentiate somatic cells into functionally mature liver cells.
Summary: The current review defines and discusses different populations of hepatic cells which can be potentially used for liver cell transplantation to advance the therapy of hepatic cirrhosis.