Stem Cells

• Stem Cell


  An unspecialized cell that can develop into a specialized cell under the right conditions
• Embryonic Stem Cell


  An undifferentiated cell, taken from an embryo that has potential to give rise to various other cell or tissue types
• Meristematic tissue


  Where stem cells are found in plants. New cells are continuously produced because the plant is always growing.
• Totipotent


  Cells that are able to develop into any type of cell found in the body.
• Pluripotent


  Cells that are capable of developing into most, but not all, of the body's cell types
• Human bone marrow


  Adult stem cells which can differentiate into a limited number of cells.
• HSC


  Hematopoietic stem cells (multipotent), can differentiate into blood cells.
• Multipotent


  Cell with limited potential to develop into many types of differentiated cells
• Parkinson's disease


  This disease kills dopamine producing neurons causing rigidity and tremors in patients. They may become depressed, lose sleep and develop dementia too.
• Treatment for parkinson's disease

  Stem cells could be grown to make dopamine producing nerve cells in the lab to study disease with. Embryonic stem cells would have to be used to make these nerve cells.
• Alzheimer's disease


  This neurological disease is one of the main causes of dementia. It causes memory lapses, confusion, mood swings and eventually memory loss. The cause is unknown but is thought to be related to the abnormal buildup of proteins in the brain.
• Possible treatment for Alzheimer's


  New neurons could replace damaged cells.

  Producing stem cells which could deliver proteins called neurotrophins to the brain. Neurotrophin production is low in Alzheimer's patients.
• Cell based therapy


  An example of this is injecting ESCs into the heart to repair cells that have been damaged after a heart attack.
• Transdifferentiation


  A form of wound healing in which mature cells dedifferentiate and produce new cells that are then able to mature into cell types with a completely different function from the originating cells eg. Liver cells could be coaxed to produce insulin (usually made in the pancreas).
• Issues


  Organ/ tissue rejection, can't control stem cell differentiation once in body, ESCs have a number of ethical issues surrounding them.