The document discusses embryonic stem cells, their potential medical applications, and the ethical issues surrounding stem cell research. It provides information on the stages of embryonic development, how embryonic stem cells are derived and can differentiate into various cell types. Therapeutic cloning is described as a potential way to generate patient-matched stem cells for transplantation without immune rejection. The challenges and politics of federal funding for stem cell research in the US are also summarized.
2. Review Embryonic Development from the Reproductive Cloning PP The next few slides are pictures to remind you of the various stages of embryonic development
9. You may never read some stories. You may read some stories only once. You might read other stories over and over. All the cells in your body contain the same exact DNA. How your cells pick and choose the genes that will be expressed or “turned on” via transcription and translation is what makes cells different. These books represent different chromosomes in all your somatic cells. The stories within are the genes. The words are the genetic code. During development, most cells of the body “differentiate”.
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11. Embryonic Stem Cells can be cultured in different laboratory environments to develop into a specific cell type. Cultured embryonic stem cells (developing an ESC line) Different culture conditions Liver cells Nerve Cells Muscle Cells Different types of differentiated cells
22. In vitro fertilization Some procedures involved with IVF manually inject the sperm into the egg, and others simply allow fertilization to occur by adding the sperm to the egg in the lab setting.
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25. Adult Stem Cells You can also find these same type of stem cells in the blood system: Peripheral Blood Stem Cells (PBSCs) Used to treat leukemia, other cancers and various blood disorders Less invasive than collecting bone marrow, but are sparse! The bone marrow is the spongy core found in the bones and is a source of adult stem cells. These stem cells are the precursor cells responsible for the formation of the blood cells (red blood cells, platelets, and white blood cells).
26. Multipotent stem cell rich blood found in the umbilical cord has proven useful in treating the same types of health problems as those treated using bone marrow stem cells Umbilical Cord Blood Stem Cells In 2005, there were more than 1,400 cord blood transplantations in adults, according to NETCORD, an international network that coordinates umbilical cord blood banks Why would a parent consider this blood collection and why might it be considered to have advantages over bone marrow stem cells? The process to collect and store a child’s cord blood doesn’t come cheap. The company “Cord Blood Registry”, for example, charges and “initial fee” of $1975 and then it is $125 per year for storage.
27. Differences between embryonic stem cells and adult stem cells: -ESC can differentiate into any cell type (totipotent/pluripotent) while adult SC have already “committed” to a particular fate (multipotent). Some Challenges in Research: -Adult stem cells are often present in only minute quantities and can therefore be difficult to isolate and purify. -There is also evidence that they may not have the same capacity to multiply as embryonic stem cells do. -They do not have the development potential that a ESC -Finally, adult stem cells may contain more DNA abnormalities—caused by sunlight, toxins, and errors in making more DNA copies during the course of a lifetime. -These potential weaknesses might limit the usefulness of adult stem cells.
30. SCNT and Stem Cells Notice that UNLIKE reproductive cloning, all we are doing here is cloning embryonic cells and then coercing them to differentiate into specific cells the patient needs.
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34. SCNT process (4) Ease the tip of the glass needle deep into the enucleated egg cell. Then, deposit the donor nucleus. Inject the nucleus (at arrow) from a donor cell into the enucleated egg cell. (Such a donor cell might be a skin cell from a disease sufferer whom doctors hope to treat using the patient’s own stem cells grown in culture)
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37. An embryonic stem cell line has now been synthesized, the cells have the same DNA as the donor. These cells can be “customized”; they can be made into any cell/tissue/organ of the body and transplanted (in theory) to the donor without immune rejection . (The cells may have their genes “corrected” before being transplanted to an individual.)
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40. How big of a role does the media play in our impressions on stem cell research? Hint: The answer is that the media plays a HUGE role!
41. The Media had a field day reporting on: Hwang Woo-Suk Hwang Woo-Suk was a professor and prominent researcher in the College of Veterinary Medicine at Seoul National University. In February 2004, Hwang and his team announced that they had successfully created embryonic stem cells with the somatic cell nuclear transfer method, and published their paper in Science (one of the most prestigious scientific journals there is) in March 2004. A second paper, published in May 2005, reported the creation of 11 stem cell lines that genetically matched nine patients with spinal cord injury, diabetes, and an immune system disorder.