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Stem Cells

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Stem Cells

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  1. Stem Cells Leah Yang

  2. Definition • Stem cell: A cell that has the ability to continuously divide and differentiate (develop) into various other kind(s) of cells/tissues

  3. Relevance • Stem cells have the ability to differentiate into other cell/tissue types, which allows them to replace cells that have died. • They have been used to replace defective cells/tissues in patients who have certain diseases or defects.

  4. History • 1998 - Researchers first extract stem cells from human embryos • 1999 - First Successful human transplant of insulin-making cells from cadavers • 2001 - President Bush restricts federal funding for embryonic stem-cell research • 2002 - Juvenile Diabetes Research Foundation International creates $20 million fund-raising effort to support stem-cell research • 2002 - California approves stem cell research • 2004 - Harvard researchers grow stem cells from embryos using private funding • 2004 - Ballot measure for $3 Billion bond for stem cells

  5. Characteristics • capable of dividing and renewing themselves for long periods of time (proliferation and renewal) • have the potential to give rise to specialized cell types (differentiation)

  6. Embryonic stem cells • derived from extra blastocysts that would otherwise be discarded following IVF • from five to six-day-old embryos • can also be grown in lab by cell culture (see next slide) • can proliferate for a year or more in the laboratory without differentiating

  7. Adult Stem cells • undifferentiated cells found among specialized or differentiated cells in a tissue or organ after birth • they have a more restricted ability to produce different cell types and to self-renew (see next slide) • can be found in many organs and tissues, including the brain and the heart

  8. kinds

  9. Pluripotent stem cells • pluripotent stem cells havemore potential to become any type of cell

  10. Multipotent stem cells • multipotent stem cells are more limited in what they can become

  11. Induced Pluripotent stem cells • IPSCs are adult cells that have been genetically reprogrammed to an embryonic stem cell–like state

  12. Applications • tissue repair -nerve, heart, muscle, organ, skin • cancers • autoimmune diseases • diabetes • rheumatoid arthritis • MS

  13. Tissues • stem cells can be used to regenerate spinal cord, heart tissue or any other major tissue in the body

  14. Bone Marrow • adult stem cells help with jumpstarting repair of eroded cartilage, and can replace damaged/destroyed bone marrow with healthy bone marrow stem cells

  15. Heart Disease • adult bone marrow stem cells injected into the hearts are believed to improve cardiac function in victims of heart failure or heart attack

  16. risks • because stem cells injected into a patient are permanent, long term side effects may not be fully understood for years • injection of embryonic stem cells may result in minor miscalculations – side effects are endless • about 20% of rats injected with embryonic stem cells later die from some form of cancerous tumor

  17. Importance of stem cell research • stem cells can replace diseased or damaged cells • stem cells can be used to test different substances (drugs and chemicals) • scientists can use stem cells to screen new drugs, and develop systems to study growth/identify the causes of birth defects • stem cells allow us to study development and genetics