Stem Cell Research – Frequently Asked Questions

Stem Cell Research – Frequently Asked Questions

Stem Cell Research – Frequently asked questions

What is an embryo? 

An embryo is the earliest form of human life. It is naturally created when sperm and egg meet and unite. This fertilised ovum, known as a zygote, is the beginning, or primordium, of a human being. In 1978 the first baby was born as a result of in vitro fertilisation (IVF). This involved bringing sperm and ovum together in the laboratory and then implanting it into the mother's womb. At this stage a new genetically distinct human being existed.   

What are stem cells?  

Stem cells are unspecialised cells that continually renew themselves through cell division. They are found in humans at all stages of life, from embryonic through to adulthood as well as in umbilical cords and placentas. 

Why is there controversy involving stem-cell research? 

There are two different kinds of stem cells: adult stem cells (ASC) and embryonic stem cells (ESC). Adult stem cells can be found in the blood, bone marrow, skin, brain, liver, pancreas, fat, hair follicle, placenta, umbilical cord and amniotic fluid. As well as showing great scientific promise in repairing damaged organs and tissues, adult stem cell research is ethically non-problematic. However, embryonic stem cell research (ESCR) requires the destruction of an embryo, which is a human being at the beginning of life.  

Why do some claim there are advantages to embryo research?

Embryonic stem cells originally were thought to have an advantage because of their flexibility and capacity to generate new cell types. However the ongoing research in animals has revealed serious side effects ranging from tumour formation to immune rejection. [1]

Are adult stem cells beneficial?

Yes. The main advantage is that they are already programmed for function in adult tissues and organs. Patients are already being treated with ASCs. Studies using ASCs include diabetes, heart disease, sickle cell anemia, acute myeloid leukaemia, multiple sclerosis, Parkinson's disease and Crohn's disease. ASCs have also successfully fought brain tumours, retinoblastoma, multiple myeloma, ovarian, testicular, and breast cancers. More than 30 anti-cancer uses for stem cells have been tested on humans, and many are already in therapeutic use.

Numerous recent studies document the pluripotent flexibility of certain adult stem cells (e.g. cord blood), proving that such versatility is not confined to stem cells taken from human embryos. [2][3][4]

What are induced pluripotent stem cells (iPSCs)?

In 2007, researchers in Japan and the US discovered that they could generate pluripotent stem cells without the need to destroy human embryos. [5] These stem cells, known as reprogrammed cells, can be generated from adult skin cells. Many scientists believe this breakthrough will mark a huge sea change in stem cell science.

Dr James Thomson, who led the US team behind the reprogramming breakthrough, says this new discovery will make the debate about the ethics of embryonic research "a funny historical footnote". Dr Robert Lanza, another expert in the field, said it marked "a new era for stem cells" and was "the biological equivalent of the Wright brothers' first airplane". Quite apart from the ethical advance achieved by this cutting edge science, reprogrammed cells or induced pluripotent stem cells (iPSCs) have a number of scientific and practical advantages over embryonic stem cells. iPSCs allow scientists to create patient-specific stem cell lines for research on human diseases.

Many scientists say that, practically speaking, iPSCs will be easier to generate than stem cells from human embryos. Also, using iPSCs does not involve human embryos or human eggs and so obtaining them doesn't require the consent of a third party.

How is the issue dealt with in other countries? 

Even countries that permit abortion are still very concerned about protecting the human embryo e.g. Italy, Germany, Austria, Poland, Malta and Slovakia among others. Unfortunately, the recent recommendations of the Irish Council for Bioethics blindly follow the British model, which has little or no respect for the human embryo inside or outside the womb.  

Conclusion

Adult stem-cell research is both effective and ethical. Embryonic stem cells are obtained by killing human embryos and as things stand are too unstable to even begin clinical trials. It's no secret that large pharmaceutical and biotech companies are refusing to fund embryonic research themselves given its very uncertain potential. They have, nonetheless, waged an extremely successful public relations campaign to secure taxpayers' funded research. This in part explains the media hype promoting destructive embryonic research. Whether or not pharmaceutical companies make exaggerated claims or blur important ethical distinctions, legislators have a responsibility not to flout empirical standards. 

We should not destroy life to prolong life. Rather we should strive for cures we can all live with.

[1] Bloom S. Stem Cell Division. J Clin Invest 2005;115:1676-7

[2] Krause DS, TheiseND, Collector MI, et al. Multi-organ, multi lineage engraftment by a single bone marrow derived stem cell. Cell2001;105:369-77

[3] Yoon Y-S, Wecker A, Heyd L, et al. Clonally Expanded multipotent stem cells from human bone marrow regenerate myocardium after myocardial infarction. J Clin Invest 2005;115:326-38

[4] Mc Guckin CP, Forraz N, Baradez N-O,et al. Production of stem cells with embryonic characteristics from human umbilical cord blood. Cell Prolif 2005;38:245-255

[5] Kyoto University, Japan and University of Wisconsin, USA, 2007