What is Known About Human Pluripotent Stem Cells?
• Since 1998, research teams have refined the techniques for growing human pluripotent cells in culture systems. Collectively, the studies indicate that it is now possible to grow these cells for up to two years in a chemically defined medium. • The cell lines have been shown to have a normal number of chromosomes and they generate cell types that originate from all three primary germ layers. • Cultures of human pluripotent stem cells have active telomerase, which is an enzyme that maintains the length of telomeres and is important for cells to maintain their capacity to replicate. Human pluripotent stem cells appear to maintain relatively long telomeres, indicating that they have the ability to replicate for many, many generations. • Evidence of structural, genetic, and functional cells characteristic of specialized cells developed from cultured human and mouse embryonic stem cells has been shown for: • Pancreatic islet-cell like cells that secrete insulin (mouse and human); • cardiac
