Ethics of Induced Pluripotent Stem Cells

Comparing IPS Cells and Embryonic Stem Cells Morally and Technically

May 21, 2009

The recently discovered induced pluripotent stem cells, or IPS cells, seem to be just as promising as embryonic stem cells without any of the ethical drawbacks.

For over a decade, nations around the world have debated and discussed the morality of embryonic stem cell (ESC) research. It is a highly contentious issue because of the ethical issues surrounding the creation, manipulation, and destruction of human life in the embryonic stage.

While many countries have passed restrictions on the research, others have left the issue untouched. The United States until very recently did not provide federal funding of stem cell research, and has no other federal regulation of the research. Thus, private US research organizations are unrestricted in the field, provided they can afford it and there are no preventative state-imposed regulations.

Ethical Issues with Embryonic Stem Cell Research

There are several key problems people frequently have with ESC research, according to ethicist Louis Guenin of the International Society for Stem Cell Research.

1. Some believe that the destruction of embryos (which is required for ESC research) destroys a human life that is worthy of legal protection or special respect. They object to killing human embryos to find medical cures.

2. ESC research that is not performed on existing embryos requires the use of eggs from human female donors. Opponents worry about the exploitation of women and the commodification of human body parts. This aspect also carries concern regarding informed consent of the women undergoing surgery for donation.

3. Some ESC research, particularly for patient-specific therapies, requires somatic cell nuclear transfer (SCNT), another term for cloning. Many people object to the idea of cloning human beings even if the embryo will not be used to create a child.

4. ESCs have not yet been used in human clinical trials or therapeutic treatment, and some people worry that the ethically problematic research is still being performed despite the success of alternative research with fewer ethical complications (such as adult stem cell research). In addition, many trials involving ESCs result in tumors or cancer development in mice subjects.

The Promise of IPS Cells

Though IPS cells are a recent discovery by James Thomson and Junying Yu of UW-Madison in the stem cell research field, many scientists are enthusiastic about their potential. IPS cells are regular skin cells that have been reprogrammed to have the same pluripotent abilities as ESCs, meaning they can be stimulated to develop into many different kinds of tissue.

Research with IPS cells initially used viruses to transform the skin cells to pluripotent cells, raising some concern over health risks to possible recipients of the cells, but the issue has since been resolved, and harmless proteins are now used to convert the cells. Although the extent of their similarity has not been fully assessed, research to date indicates that IPS cells are biologically equivalent to ESCs in virtually every way.

IPS cells can turn into any type of cell in the body, and have been successfully developed with both mouse and human cells. Because the process for inducing cells to pluripotency is not as ethically or technically complicated as working with ESCs, many researchers believe IPS cells hold more practical promise for routine research and future medical use.

IPS Cell Ethics

IPS cells do not involve the use or destruction of human embryos or eggs, do not involve risk to women donors, and do not have oncogenic (cancer-related) growth problems like ESCs, but there are still some concerns that creating these cells does not solve the entire ethical roadblock, according to Francoise Baylis, an expert ethicist on ESC research and IPS cells.

In an online article entitled "ES Cells and iPS Cells: A Distinction with a Difference" for the Hastings Center in March of 2008, Baylis noted that if IPS cells eventually demonstrate totipotency, which is required for the generation of a new human life, they would essentially be human embryos, negating any advantage IPS cells may have over ESCs in terms of the destruction of early human life.

Although this is not currently a problem, philosophical debates over this possibility currently occupy many discussions of IPS cell ethics. For the time being, IPS cells have not been able to be manipulated to grow the outer layer of an embryonic cell required for the development of the cell into a human being.

Future developments in the field of IPS cell research should clarify its true ethical standing in comparison to ESC research.

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The copyright of the article Ethics of Induced Pluripotent Stem Cells in Scientific Ethics is owned by Katherine Brind'Amour. Permission to republish Ethics of Induced Pluripotent Stem Cells in print or online must be granted by the author in writing.