Researchers, through the University of California, San Diego (UCSD) Superfund Research Program (SRP) Center, have discovered a population of liver cells that are better at regenerating liver tissue than ordinary liver cells, or hepatocytes. The study is the first to identify these so-called "hybrid hepatocytes" and show that they are able to regenerate liver tissue without giving rise to cancer. While most of the work described in the study was done in mouse models, the researchers also found similar cells in human livers.