What are Stem Cells - How Do They Help With Cancer and Other Diseases

What are Stem Cells?

Stem cells multiply by infinitely dividing themselves and turning into another stem cell, or becoming another type of cell altogether, such as a muscle cell, a red blood cell, or a brain cell.

There are three different types of stem cells - embryonic stem cells (from embryos), adult stem cells (from adults), and lesser known embryonic germ cells (from a fetus).

Embryonic Stem Cells

Embryonic stem cells, unlike adult stem cells are "pluripotent" and can regenerate into over 200 cell types that make up all tissues - such as nerve, bone, cartilage, and muscle cells.

Embryonic stem cells are obtained from the 'inner cell mass' of 4-5 day old human embryos, called a blastocyst, which contain 30-150 cells.

Adult Stem Cells

These cells are found in adult tissues and act as the body's repair system, replenishing specialized cells plus regenerative organs, such as blood, skin or intestinal tissues.

These are generally obtained for research via umbilical cord blood, bone marrow, skin cells or fat. Adult stem cells ar also contained in the brain, muscle and liver.

Induced Pluripotent Stem Cells (iPS or iPSC)

These are a type of pluripotent stem cell artificially derived from a non-pluripotent cell.

In other words, an adult stem cell was used to create an artifical embryonic stem cell.

These were first produced in 2006 (mice) and 2007 (humans).

These iPSC cells may allow scientists to avoid the controversial use of embryos.

Embryonic Germ Cells

Research into human embryonic germ (hEG) cells have received little attention. hEG cells are only collected from the testes of a 7-9 week cadaver fetus. Collection and study of hEG cells raises many ethical questions concerning abortion, and the destruction of human tissue.

What's so Great About Stem Cells

The ability of a stem cell to become any type of cell fascinates scientists. They could potentially repair tissues or treat diseases. Stem cells can be grown into specialized cells for muscles and nerves.

What Has Been Done So Far?

Per CBC News, most studies have been done on lab animals:

• Improved stroke recovery in rats.
• Embryonic stem cells were used to treat a Parkinson's like condition in mice and rats.
• New brain cells grown from adult stem cells in birds.
• Canadian and Italian scientists transplanted adult stem cells from mice brains into the bone marrow of other rodents. These stem cells changed behaviour and began making blood cells.
• Movement was restored in paralyzed mice and rats by injecting stem cells into the spinal fluid.

Is this Cloning?

Yes and No. Stem cells will not create a complete person or animal - like Dolly the sheep. However, stem cells are able to create millions of copies of themselves.

U.S. Policy

Under President George W. Bush, federal money for research on human embryonic stems cells was limited to those stem cell lines, or families of constantly dividing cells, that were created before Aug. 9, 2001. No federal dollars could be used on research with cell lines from embryos destroyed from that point forward.

Federal regulations do not restrict embryonic stem cell research using state or private funds.

Debate about Ethical Issues

Harvesting stem cells from four- or five-day-old embryos kills the embryo, which outrages opponents of this type of research. They say that any embryo has the potential to develop into a human.

But supporters say hundreds of thousands of embryos stored in fertility clinics eventually will be destroyed anyway and that people should be allowed to donate them for research that could help others.

Obama Campaign Quotes

As president, I will lift the current administration's ban on federal funding of research on embryonic stem cell lines created after August 9, 2001, through executive order, and I will ensure that all research on stem cells is conducted ethically and with rigorous oversight.

Argument for Federal Funding

Advocates - American Society for Reproductive Medicine

These embryos would otherwise be discarded.

Is it ethically more acceptable to destroy these embryos by pouring acid on them, or do you deploy these clusters of cells to create new cell lines that could benefit us in the future?

Opponent's Argument

Opponents - Family Research Council, Concerned Women for America

The main argument is that life begins at conception — that once fertilization occurred in the lab, so did a human being. Secondly, they will argue that scientists are having success using other methods — adult stem cells that form specific tissues, or reprogramming skin cells to act like stem cells — so money should be directed where the biggest scientific breakthroughs have occurred. For example, this past week, doctors gave a woman a new windpipe with tissue grown from her own stem cells, eliminating the need for anti-rejection drugs.