Stem Cells: Miracle Cure? Avionna Baldwin J. Onyi Oradiegwu SAMS 2008 What is Tissue Engineering/ Regenerative Medicine? Replacing diseased or injured tissues with tissue constructs designed and fabricated for the specific needs of each individual patient. What are Biomaterials? A material intended to interface with biological systems to evaluate, treat, augment or replace any tissue, organ or function in the body. Still thousands die while waiting for a transplant, and thousands more aren’t even on the list. 400 bil: ½ of national health care bill goes to patients with organ failure, or tissue loss Five hottest jobs for the next millennium will be bioengineering/biomedical related. Tissue Engineering Hottest job for 21st Century No One Discipline Can Tackle the Problem Alone Lee Weiss, Carnegie Mellon Normal Wound Repair Requires a Balance of Processes The Basic Three Rs of Tissue Engineering Right Hormones Matrices Right ECM Cells Healing Signaling Molecules Right Cells Guided Tissue Repair If needed, harvest cells from patient. Biomimetic extracellular matrix Lee Weiss, Carnegie Mellon Culture Implant Principles of Tissue Engineering Cells ECM Defect Hormones Phil Campbell, Carnegie Mellon Regeneration Blood Supply What about the cells? Adult stem cells look promising for some applications Embryonic stem cells great potential, controversial The right hormones can induce these cells to become a variety of cell types • A cell that is able to differentiate into many cell types is known as pluripotent – Can’t grow into a totally new indiv. Because they don’t make extraembryonic structures like placenta • A cell that is able to differentiate into all cell types is known as totipotent. – Can go full on into a new indiv. They can make a placenta – Amazing: plants are way easier to find totipotent cells in Beast boy can turn into any animal adipocyte osteoblast hematopoetic/endothelial cells muscle cell chondrocyte Adult MuscleDerived Stem Cells (MDSCs) nerve cells/neurons/glial cell hepatocyte/urinary bladder cells Pancreatic islets?? Derivation of Human Embryonic Stem Cells (hESC’s) http://stemcells.nih.gov/staticresources/info/scireport/PDFs/Chapter8_final.pdf Derivation of Human Embryonic Stem Cells (hESC’s) http://stemcells.nih.gov/staticresources/info/scireport/PDFs/Chapter8_final.pdf Modified Cell Stem Cell Induction or Derivation. http://stemcells.nih.gov/staticresources/info/scireport/PDFs/Chapter8_final.pdf http://stemcells.nih.gov/staticresources/info/scireport/PDFs/Chapter8_final.pdf Adult Stem Cell Derivation Stem Cell Differentiation Princeton University Stem Cell Cultivation University of Wisconsin-Madison Human Stem Cell Production Tissue origins • Embryonic cells present molecules on their membranes that aid in the early organizing process – Ectoderm, mesoderm, endoderm You’ve got stem cells in you right now • Note: Progenitor cells: a term like stem cells, but less restrictive • Adults have stem cells in blood marrow. – They’re multipotent, but not pluripotent – Might have suffered ravages of time, sunlight, and toxins, that come with aging • There are also stem cells in umbilical cords • Embryonic stem cells = controversy Bo is like a pluripotent athlete. An Ultimate Vision for Regenerative Medicine: Complete Tissue Regeneration Spinal Cord Retina and Lens Tail Upper and Lower Jaw Heart Limb The Newt From Dr. Susan Bryant, Univ.from of Calif., Irvine Adapted Brockes Phil Campbell, Carnegie Mellon And lots of tissue engineering research looks very promising For example, tissue-engineered nerve guides for treatment of spinal cord injuries • After induced put in the video and see the clip to implement the stem cell Medical Implants Millions of People in the US Have Medical Implants Associated with a $50 billion/year Medical Device Industry FDA approved products Infuse Bone Graft Bone morphogenetic protein-7, Osteogenic peptide-1 Regranex Carticel Transcyte Intergra Dermal Regeneration Template Dermagraft Apligraft Ortec Short form: Know the argument • Proponents – They’re from embryos that are slated for destruction anyway – Great potential for good – Superman was for it • Only for embryoes that were going to be discarded • Opponents – Destroys embryos – Devalues worth of human •Hot research area: harvest embryonic stem cells without destroying the embryo. Proponents Argument in depth – Embryonic stem cells are more useful – Utilitarian • The benefits of stem cell research outweigh the cost in terms of embryonic "life“ – human potential vs humanity • The value of an embryo should not be placed on par with the value of a child or adult • Life starts with a heartbeat – Ends justify the means – Efficiency • If an embryo is going to be destroyed anyway, isn't it more efficient to make practical use of it? • In Vitro Fertilization makes thousands of unusable embryos Opponents arguments in depth – Embryos are lives • Life starts at conception • Note Roe v. Wade said life = viability, ability to survive outside of womb, medical advancements have pushed this back to 22 weeks. Could trend continue? – Exploring alternative therapeutic options • We’ve studied adult stem cells longer and have more therapies with them that with embryonic – The potential is overstated Legal Sweden Finland Belgium Greece the United Kingdom, Denmark Netherlands China Japan Korea Taiwan Israel Iran Illegal Germany Austria Ireland Italy Portugal. Most of middle east Africa, except S. Africa S. America, except Brazil