EMBRYONIC STEM CELLS

An introduction to the science, ethics and legislation

Day 1: Groups/articles assigned Feb. 14

Day 2: Library – Feb 24

Day 3: Presentations – Feb 27/28

Day 4: Committee presents: March 3rd

What is a stem cell?

Stem cells can become other types of cells

Stem cells can also divide indefinitely stem cell line

Pluripotent vs multipotent stem cells

Reproduced by Permission of Professor Rathjen of the University of Adelaide

http://www.sumanasinc.com/webcontent/animations/content/stemcells_scnt.html

Potency

Potency describes the potential of stem cells to differentiate into different cell types

Totipotent stem cells can differentiate into embryonic and

extraembryonic cell types (cells that do not become part of the fetus – like placenta).

can construct a complete, viable, organism. cells are produced from the fusion of an egg and

sperm cell. Cells that are produced by the first few divisions

of the fertilized egg are also totipotent.

Pluripotent stem cells the descendants of totipotent cells can differentiate into nearly all cells. (just

not placenta)

Multipotent stem cells differentiate into cells of closely related

family of cells (e.g. hemapoietic cells can become several different types of blood cells, but not a brain cell).

http://www4.od.nih.gov/stemcell/figure3big.gif

Embryonic (ES) vs Adult Stem (AS)cells

ES cells are pluripotent AS cells found in small amounts

throughout body Most AS cells appear to be multipotent

ES cells come from ICM of blastocyst

Reproduced by permission of the NIH

Why all the fuss?

Stem cells may be able to replace damaged cells in the body

Today: lymphoma, leukemia

Future? Parkinson’s, Alzheimer’s, diabetes...

Promising animal studies

Reproduced by permission of The Providence Journal

Courtesy of The Michael J. Fox Foundation for Parkinson’s Research

Sources of ES cells

ES cell lines Excess embryos from IVF clinics Embryos created for research by IVF Therapeutic cloning

Reproduced by permission of the NIH

Induced pluripotent stem cells (iPSCs)

adult cells that have been genetically reprogrammed to an embryonic stem cell–like state .

Human iPSCs were first reported in late 2007. They are capable of differentiating into all types of cells.

Viruses are currently used to introduce the

reprogramming factors into adult cells, and this process must be carefully controlled and tested before the technique can lead to useful treatments for humans. In animal studies, the virus used to introduce the stem cell factors sometimes causes cancers.

http://archives.cbc.ca/health/medical_research/clips/17505/

Cloning

Purpose of therapeutic cloning is to harvest ES cells for treatment blastocyst destroyed

Purpose of reproductive cloning is to make new person blastocyst implanted in uterus

Reproduced by permission of the NIH

Cloning

Why the interest?

Ethical debate

Harvesting ES cells destroys the blastocyst

“This is murder”

Reproduced by permission of Dave Catrow and Copley News Service

Ethical debate, cont’d ES cell research

requires human cells

Could create a commercial market for human cells

“This devalues life”

Courtesy of Kevin Siers, The Charlotte Observer © 2001

Ethical debate, cont’d

“If excess IVF embryos are being discarded anyway, they should be put to good use”

Reprinted by permission of Chip Bok and Creators Syndicate, Inc.

Ethical debate, cont’d

“Therapeutic cloning is a slippery slope - it will lead to reproductive cloning”

Reproduced by permission of Gary Markstein and Copley News Service

http://www.youtube.com/watch?v=7Y5H9Sasq5U

Project Overview

We are all citizens of Adanac

There is the need to draft legislation (laws) to decide on the use of embryonic stem cells in our country.

Project Overview The legislation must address:

1. The use of embryonic stem cells from existing cell lines

2. The use of embryonic stem cells from discarded embryos from in vitro clinics

3. The use of embryonic stem cells from embryos created by IVF for research

4. The use of embryonic stem cells from embryos created by therapeutic cloning.

Project Overview

There will be a committee who will hear the views of concerned citizen groups.

The committee will be responsible for creating the legislation based on discussion and what they hear from the public.

Project Overview The class will be divided into focus

groups – each group will prepare a presentation for the committee.

Focus Groups: Scientists Industry Volunteer Health Organizations Religious Groups Bioethicists

Steps You will get an article from the

perspective of your focus group. Read the article and summarize the ideas

on the sheet provided. Next week – get the presentation guide

and start working on it in groups. Computer day booked for FEB 24th time

to put together PPT. presentation on your group’s position.

This is not YOUR opinion – you must take the perspective of the group you represent.

Governing ES cell research

Country Therapeutic

cloning

Creation of embryos for

research

Use of excess embryos from

IVF clinics

Use of existing ES cell lines

UK

US ? Canada

Germany