NOTES 27 – Embryonic Stem Cells and Cloning

What are stem cells? Embryonic Stem Cells – cells present in the early stages of an embryo’s development that have the ability to change in any type of body cell

What are the goals of stem cell research? Stem cell research is about repairing and/or replacing damaged body tissues in order to reverse some effects of aging, disease, and injury In the lab, scientists have seen embryonic stem cells change into the cells of virtually every part of the human body Scientists want the ability to control the development of these cells so they can make the types of tissue they need, like brain, heart, nerve, or muscle

Stem Cells in the Lab

The Potential of Stem Cells Stem cells can be used to generate cells and tissues that could be used for cell-based therapies Cell-based therapies —Treatment in which stem cells are changed into the specific cell type required to repair damaged or destroyed cells or tissues Donated organs and tissues are often used to replace damaged or destroyed tissue, but the need for transplantable tissues and organs far outweighs the available supply Stem cells changed into specific cell types, offer the possibility of a renewable source of replacement cells and tissues to treat many diseases (Parkinson's and Alzheimer's diseases, spinal cord injury, stroke, burns, heart disease, diabetes, osteoarthritis, and rheumatoid arthritis)

The Potential of Stem Cells It may become possible to generate healthy heart muscle cells in the laboratory and then transplant those cells into patients with chronic heart disease. Research in mice and other animals indicates that stem cells transplanted into a damaged heart can generate heart muscle cells and successfully repopulate the heart tissue The Potential of Stem Cells

Mouse

The Potential of Stem Cells In people who suffer from type I diabetes, the cells of the pancreas that normally produce insulin are destroyed by the patient's own immune system New studies indicate that it may be possible to change human embryonic stem cells to insulin-producing cells that eventually could be used in transplantation therapy for diabetics

Where do embryonic stem cells come from? Embryonic stem cells must be taken from the earliest stage of the embryo, called the blastocyst 5 to 7 days after fertilization, the blastocyst is ball of about 100 stem cells There are two ways to produce blastocysts from which stem cells can be taken: fertilization of egg with sperm or cloning

Where do embryonic stem cells come from?

Where do embryonic stem cells come from?

Where do embryonic stem cells come from?

Where do embryonic stem cells come from?

Where do embryonic stem cells come from?

Where do embryonic stem cells come from?

Blastocyst

What is cloning?

What is cloning? Cloning – making a genetic copy of an existing organism There are 2 types of cloning: Reproductive Cloning – cloning in order to produce a genetic copy of an existing organism Therapeutic Cloning – cloning in order to produce a blastocyst from which stem cells can be taken and used to develop therapies for injury and disease

How does reproductive cloning work?

How does reproductive cloning work?

How does reproductive cloning work?

How does reproductive cloning work?

How does reproductive cloning work?

How does reproductive cloning work?

How does reproductive cloning work?

How does reproductive cloning work?

Reproductive Cloning

How does therapeutic cloning work? Therapeutic cloning begins the same way as reproductive cloning Instead of implanting the blastocyst into a surrogate mother, the stem cells are taken out of the blastocyst and used to develop whatever type of cells are needed

Cloned Embryo Stem Cells

What’s all the fuss about? When embryonic stem cells are removed from the blastocyst, the embryo is destroyed Is this the same as abortion? What rights does the blastocyst deserve? In 2001, President George Bush placed a ban on federal funding for embryonic stem cell research

Researchers Cheer Obama's Vote for Stem-Cell Science President Barack Obama signs an Executive Order reversing the government's ban on funding stem-cell research, during a ceremony in the East Room of the White House on March 9, 2009