Stem Cells

• Differentiate into specialised cells
• Regenerate an infinite number of times
• Totipotent -> Pluripotent -> Multipotent -> Unipotent
• Totipotent cells: can divide into any type of cell from embryonic stem cells.
• Pluripotent cells: in animals, have the potential to differentiate into any body cell except the placenta.
• Multipotent cells: adult stem cells, differentiate further can only give rise to a limited number of different types of cell.
• Unipotent cells: can only differentiate into a single type of cell. Made in adult tissue.
• Induced Pluripotent stem cells (iPS)

  • Derived from unipotent cells
  • Genetically altered to behave like embryonic stem cells (a type of Pluripotent cell)
  • This turns on genes that were turned off
  • Shows that adult cells can still contain genes present in the embryo
  • Can self renew so could replace embryo cells in research.
• Cardiomyocytes

  • A type of unipotent stem cell
  • Cardiomyocytes are unipotent heart cells
  • Can replicate to replace damaged or aged cells