4D - stem cells

• S


  Stem Cells
• TPMOV


  Totipotent, Pluripotent, Multipotent, Oligopotent , Unipotent—> specialised cells
• At the start of life, stem cells divide over and over again
• Stem cells are the building blocks of the human body
• Stem cells can be used to create a full person from an embryo
• As you age, stem cells replenish cells in your blood, bone, skin and organs
• Stem cells can be powerful tools in treating injury and illness
• Self-renewal


  Stem cells maintain their own population by dividing and renewing themselves
• Stem cell differentiating


  Stem cells specializing into different cell types
• Specialized cell


  Cells that have become specialized, e.g. muscle, nerve cell
• If stem cells don't copy themselves, they would run out
• It is important for the body to maintain a pool of stem cells to use throughout life
• Differentiation


  Specialized cells are used up, damaged or die during life, and need to be replaced
• The body needs 100,000 new blood cells everyday
• Differentiation is also important for making all different kinds of cells in the body during development from a single fertilized egg
• Embryonic stem cells


  Stem cells found in the blastocyst, a very early stage of development
• Tissue stem cells


  Stem cells found in the fetus, baby and throughout life
• Potency


  A measure of how many types of specialized cells a stem cell can make
• Pluripotent


  Can make all types of specialized cells in the body
• Multipotent


  Can make multiple types of specialized cells, but not all types
• Totipotent


  Stem cells that can differentiate into any cell type, including extra-embryonic cells
• Zygote


  Cell produced following fertilization of an egg cell by sperm, can differentiate into all cells required to build a person
• Unipotent


  Stem cells that can differentiate into a single cell type
• Embryonic stem cells


  Found in early stages of a developing embryo, can differentiate into all cell types of the body (except the placenta)
• Multipotent stem cells


  Can differentiate into a limited number of specialized cell types belonging to a specific tissue or organ
• Multipotent stem cells


  • Blood stem cells (can differentiate into RBC, WBC, platelets)
  • Mesenchymal stem cells (can differentiate into bone, cartilage, muscle, fat cells)
• Embryonic stem cells


  Blank slate cells that can become any type of cell in the body, can divide and multiply endlessly, controversial as embryos must be destroyed to obtain them
• Adult stem cells


  Mature stem cells that replenish blood, skin, gut and some other cells, have limited ability to become other cell types and divide/multiply
• Induced pluripotent stem (iPS) cells


  Adult cells that are programmed to look and act like embryonic stem cells, can be made from skin, blood and other adult cells
• Embryonic stem cells are removed from the embryo in the blastocyst stage and can be multiplied or differentiated in the lab
• Embryonic stem cells are the starter cell of the human body, are undifferentiated, and are able to become any cell in the body
• Embryonic stem cells can multiply and differentiate to become organs, bones and muscles
• Embryonic stem cells are isolated from 3-5 day-old embryos donated by people who have gone through in-vitro fertilization
• Embryonic stem cells


  • Only stem cells that are naturally able to become any other cell types and to multiply endlessly
  • Under the right circumstances in the lab can be nudged to become cell types they normally wouldn't
• Medical potential of embryonic stem cells

  Their ability to differentiate and multiply endlessly makes them the most powerful stem cells, with potential to treat injuries and illnesses
• Scientists are able to control how and how often embryonic stem cells differentiate, allowing them to be used to replace damaged parts of the body
• Ethical problems and potential for mutations are limitations of embryonic stem cell therapies
• Adult stem cells


  More mature than embryonic stem cells, limited in their ability to differentiate
• Adult stem cells are found in many of the body's organs and replenish cells in the organs they reside in
• Adult stem cells


  • Limited in their abilities, can only become certain types of cells (multipotent) instead of all cell types (pluripotent)
  • Limited in how much they can divide