Stem Cells by Sejul Jaiswal.ppt
- 2. Importance of Stem Cell Research
- 4. WHAT ARE STEM CELLS? ■ A cell that has the ability to continuously divide and differentiate (develop) into various other kind(s) of cells/tissues
- 5. Stem Cell Characteristics ■ ‘Blank cells’ (unspecialized) ■ 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. Types of Stem Cells Stem cell type Description Examples Totipotent Each cell can develop into a new individual Cells from early (1-3 days) embryos Pluripotent Cells can form any (over 200) cell types Some cells of blastocyst (5 to 14 days) Multipotent Cells differentiated, but can form a number of other tissues Fetal tissue, cord blood, and adult stem cells
- 7. This cell Can form the Embryo and placenta This cell Can just form the embryo Fully mature
- 8. Kinds of Stem Cells Embryonic stem cells • five to six-day-old embryo • Tabula rasa Embryonic germ cells • derived from the part of a human embryo or fetus that will ultimately produce eggs or sperm (gametes). Adult stem cells • undifferentiated cells found among specialized or differentiated cells in a tissue or organ after birth • appear to have a more restricted ability to produce different cell types and to self-renew.
- 9. Pluripotent Stem Cells – more potential to become any type of cell
- 10. Multipotent stem cells ■ Multipotent stem cells – limited in what the cells can become
- 11. Embryonic Stem Cells Mainly from IVF
- 13. Stages of Embryogenesis blastocyst Blastocyst inner mass cells 8-cell stage cleavage
- 15. Induced Pluripotent Stem Cells
- 16. • Skin • Fat Cells • Bone marrow • Brain • Many other organs & tissues Adult Stem Cells An undifferentiated cells found among specialized or differentiated cells in a tissue or organ after birth
- 17. Bone Marrow ■ Found in spongy bone where blood cells form ■ Used to replace damaged or destroyed bone marrow with healthy bone marrow stem cells. ■ Treat patients diagnosed with leukemia, aplastic anemia, and lymphoma ■ Need a greater histological immunocompatibility
- 18. Umbilical cord stem cells ■ Also Known as Wharton’s Jelly ■ Adult stem cells of infant origin ■ Less invasive than bone marrow ■ Greater compatibility ■ Less expensive
- 19. Umbilical cord stem cells Three important functions: 1. Plasticity: Potential to change into other cell types like nerve cells 2. Homing: To travel to the site of tissue damage 3. Engraftment: To unite with other tissues
- 20. Stem Cell Applications • Tissue repair - nerve, heart, muscle, organ, skin • Cancers • Autoimmune diseases - diabetes, rheumatoid arthritis, MS
- 22. Tissue Repair • Regenerate spinal cord, heart tissue or any other major tissue in the body.
- 23. Replace Skin
- 24. Heart Disease • Adult bone marrow stem cells are injected into the hearts are believed to improve cardiac function in victims of heart failure or heart attack
- 26. Leukemia and Cancer • Studies show leukemia patients treated with stem cells emerge free of disease. • Injections of stem cells have also reduces pancreatic cancers in some patients. Proliferation of white cells
- 27. Rheumatoid Arthritis • Adult Stem Cells may be helpful in jumpstarting repair of eroded cartilage.
- 28. Type I Diabetes • Pancreatic cells do not produce insulin • Embryonic Stems Cells might be trained to become pancreatic islets cells needed to secrete insulin.
- 29. Stem cells in the adult brain: BRAIN REGENERATION
- 30. Technical Challenges ■ Source - Cell lines may have mutations ■ Delivery to target areas ■ Prevention of rejection ■ Suppressing tumors
- 31. Mutations can lead to leukemia Problems with Adult Stem Cells
- 32. Why is Stem Cell Research So Important to All of Us? Stem cells can replace diseased or damaged cells Stem cells allow us to study development and genetics Stem cells can be used to test different substances (drugs and chemicals)
- 33. Why the Controversy Over Stem cells? ■ Embryonic Stem cells are derived from extra blastocysts that would otherwise be discarded following IVF. ■ Extracting stem cells destroys the developing blastocyst (embryo). -Questions for Consideration- ■ Is an embryo a person? ■ Is it morally acceptable to use embryos for research? ■ When do we become “human beings?”