Transcript Slide 1
Will Stem Cells Finally Deliver Without Controversy? Keith Gary, Ph.D. Director of Program Development Kansas City Area Life Sciences Institute Olathe North Life Sciences 1 February 2012 What’s the Buzz? PROMISE POLITICS Promise Politics Ethical Dilemma Right To Life Movement Young Scientific Field – little data Not Amenable to Sound Bytes Sexual Reproduction Stages of Development The Blastocyst 3-5 days post-fertilization Inner cell mass = ~30 cells Fate of Embryonic Tissues Germ Layer Organs and Tissues in Adult Ectoderm Skin epidermis, epithelium of mouth and rectum, cornea and lens of eye, nervous system, tooth enamel Endoderm Epithelium, digestive tract and respiratory system; liver, pancreas, thyroid; lining of urethra, bladder, reproductive system Mesoderm Skeletal and muscular systems; circulatory & lymphatic systems; reproductive system (except germ cells); dermis of skin, lining of body cavity Seminal Events 1978 – First successful in vitro fertilization 1981 – Mouse embryonic stem cells grown in lab 1985 – Drug stimulated superovulation 1998 – First human embryonic stem cell line What is a Stem Cell? Self-renewing undifferentiated cells with the ability to repair damaged tissue. Early Stage Stem Cells (Embryonic) Undifferentiated cells that are pluripotent and have the potential to become any type of tissue of the body. Early Stage Stem Cells are Pluripotent Early Stage Stem Cells Somatic Cell Nuclear Transfer (SCNT) Produces stem cells genetically identical to donor Not a new individual No fertilization Are The Blastocysts Identical? IVF SCNT Adult Stem Cells Undifferentiated cells found in a tissue or organ that are multipotent and can become more than one type of tissue, but not all types. The Human Body Contains > 10 trillion cells with 250 different cell types Some tissues continually renew themselves from adult stem cells Adult vs. Embryonic Stem Cells ES AS Pluripotent Multipotent Limiting differentiation in culture is problematic More stable, easier to manage Potentially immortal, unlimited supply Lose ability to proliferate and differentiate in culture High ethical burden, uncertain legal status Less moral ambiguity and controversy Potential Disease Targets Alzheimer’s Disease Cancer Diabetes (Type I) Heart Disease Macular Degeneration Osteoarthritis Parkinson’s Disease Rheumatoid Arthritis Spinal Cord Injuries Stroke U.S. Disease & Injury Statistics Dan Perry, Executive Director of CAMR. Science (2000) 287: 1423. Examples of Potential Treatments Type I Diabetes –Replace pancreatic cells to restore normal blood sugar. Burn Treatment –Regenerate functional skin following severe burns. Alzheimer’s & Other Neurological Diseases –Regenerate neural cells and restore brain/body communication to alleviate symptoms of Alzheimer’s, ALS, multiple sclerosis & Parkinson’s. Spinal Injuries – Restore function to damaged spinal cords (successful in tests with paralyzed rats - regained ability to walk). How Does Stem Cell Research Relate to Human Cloning? Cloning Animals • Multiple examples of successful cloning efforts – Dolly: 1 out of 276 attempts – Mouse: 100 blastocysts transferred to wombs, seventy-one were able to take, from which between five and sixteen fetuses developed, and eventually two or three live mice were born • “Therapeutic Cloning” Human Cloning Must be made illegal with substantive penalties and strict enforcement Human Cloning Ethical Alternatives Altered Nuclear Transfer •William Hurlbut, Stanford •Genetic alteration in adult nucleus that represses a protein necessary for trophoblast maintenance. •Zygote unable to implant in uterus. Ethical Alternatives Blastomeres ESC •Advanced Cell Technology report •Preimplantation Genetic Diagnosis technique commonly used during IVF to detect genetic disorders. •Long-term consequences have not been adequately addressed. Ethical Alternatives Induced pluripotent stem cells (iPSCs) •adult cells genetically reprogrammed to an embryonic stem cell–like state. •express genes and factors important for maintaining the defining properties of embryonic stem cells. •Although iPSCs meet the defining criteria for pluripotent stem cells, it is not known if they differ from embryonic stem cells in clinically significant ways. Induced pluripotent stem cells (iPSCs) What the scientific community knows about stem cells • The most “plastic” cells are early stage • Some adult stem cells have differentiative potential • Other sources exist (Fetal Cord Blood) • Current stem cell lines approved for government funded studies are inadequate to drive research forward Clinical Trials FDA Delays Clinical Trial of Embryonic Stem Cells May 2008 FDA OKs 1st Embryonic Stem Cell Trial January, 2009 Geron Initiates Clinical Trial of Human Embryonic Stem CellBased Therapy - October, 2010 Second human embryonic stem cell clinical trial to start November, 2010 Take Home Message • Stem cells have great potential benefits for agriculture and biomedical sciences. • Efficiencies are very low and research needs to be done before stem cells will be of benefit to society. • Its important for scientists to be proactive and educate the general public, media and government. Additional Information • National Institutes of Health http://stemcells.nih.gov/info/basics/ • University of Wisconsin http://www.news.wisc.edu/packages/stemc ells • Coalition for the Advancement of Medical Research http://www.camradvocacy.org/stem_cell_ne ws.cfm