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1981 — Two scientists, Martin Evans of the University of Cambridge and Gail Martin of the University of California, San Francisco, conduct separate studies and derive pluripotent stem cells from the embryos of mice. These early cells are the first embryonic stem cells ever to be isolated.Apr 28, 2010
Stem cell therapies are not new. Doctors have been performing bone marrow stem cell transplants for decades. But when scientists learned how to remove stem cells from human embryos in 1998, both excitement and controversy ensued. The excitement was due to the huge potential these cells have in curing human disease.
Key Moments in the Stem-Cell Debate The first embryonic stem cells were isolated in mice in 1981. But it wasn’t until 1998 that researchers managed to derive stem cells from human embryos. That kicked into full gear an ethical debate that continues to this day. Here’s a look at key moments in the controversy so far.
James Alexander Thomson
James Alexander Thomson is an American developmental biologist best known for deriving the first human embryonic stem cell line in 1998 and for deriving human induced pluripotent stem cells (iPS) in 2007.
Historically, the use of stem cells in medical research has been controversial. … Many people disagree with using human embryonic cells for medical research because extracting them means destroying the embryo. This creates complex issues, as people have different beliefs about what constitutes the start of human life.
There are no ethical or moral concerns with the appropriate use of adult stem cells. However, human embryonic stem cell (HESC) research is unethical since it results in the destruction of human life for research purposes.
Stem cells were first used for bone marrow transplants (BMTs), a proceedure that was introduced as a treatment for cancer and genetic blood disorders in the 1960s. Every year stem cells are presently used in about 60,000 BMT operations worldwide.
Also known as somatic stem cells, they can be found in children, as well as adults. Research into adult stem cells has been fueled by their abilities to divide or self-renew indefinitely and generate all the cell types of the organ from which they originate — potentially regenerating the entire organ from a few cells.
Additionally, under defined conditions, embryonic stem cells are capable of propagating themselves indefinitely. This allows embryonic stem cells to be employed as useful tools for both research and regenerative medicine, because they can produce limitless numbers of themselves for continued research or clinical use.
Founded by Dr. Neil Riordan, a globally recognized stem cell expert and visionary, the Stem Cell Institute in Panama is among the world’s leaders in stem cell research and therapy. Their treatments focus on well-targeted combinations of allogeneic umbilical cord stem cells, as well as autologous bone marrow stem cells.
James Thomson, in full James Alexander Thomson, (born Dec. 20, 1958, Chicago, Ill., U.S.), American biologist who was among the first to isolate human embryonic stem cells and the first to transform human skin cells into stem cells.
Scientists discovered ways to derive embryonic stem cells from early mouse embryos nearly 30 years ago, in 1981. The detailed study of the biology of mouse stem cells led to the discovery, in 1998, of a method to derive stem cells from human embryos and grow the cells in the laboratory.
On August 9, 2001, U.S. President George W. Bush introduced a ban on federal funding for research on newly created human embryonic stem (ES) cell lines. The policy was intended as a compromise and specified that research on lines created prior to that date would still be eligible for funding.
For every embryo that is donated to others, more than 100 embryos are discarded. Currently, more than 400,000 embryos are frozen in fertility clinics, and most will eventually be discarded.
Some argue that as long as the decision to donate embryos for research is made after the decision to discard them, it is morally permissible to use them in HESC research even if we assume that they have the moral status of persons. The claim takes two different forms.
The Catholic Church has opposed human embryonic stem cell research and any kind of human cloning because they are contrary to the dignity of procreation, of conjugal union and of human embryos.
The Catholic Church has become the leading voice against any form of human cloning and even against the creation of human embryonic stem-cell lines from ‘excess’ in vitro fertilization (IVF) embryos.
Rank | Country/Territory | Number of clinical trials |
---|---|---|
1 | United States | 136 |
2 | Iran | 65 |
3 | South Korea | 40 |
4 | Australia | 18 |
When McCulloch and Till transplanted bone marrow cells into lethally irradiated mice, they noticed small lumps on the mice’s spleens. They later concluded that the lumps were clones of cells arising from a single cell, now called a stem cell.
When a sperm fertilizes an egg, it becomes what is known as a “zygote.” Many scientists view the zygote as the ultimate stem cell because it can develop into any cell not only of the embryo, but also of the surrounding tissues, such as the placenta.
As the fertilized egg divides to make an embryo, cells become specialized gradually. … Less than three weeks after a human egg has been fertilized, these most flexible of stem cells have disappeared and embryonic cells become gradually more restricted in their potential.
Embryonic stem cells (ESCs) are derived from the embryo and have the potential to become all the different cell types of the body (pluripotency). … Cord blood stem cells can be isolated from the umbilical cord of newborn infants and are less mature than adult stem cells.
Embryonic stem cells (ESCs) derived from the inner cell mass of a blastocyst are pluripotent stem cells with unique properties of pluripotency and self-renewal. They can divide indefinitely in vitro, while maintaining the capacity to generate all the cell types of an adult organism.
Q. Which is true about embryonic stem cells? They no longer divide, their cell type is set and cannot change. … They can become any cell type in the body.
Consider the blastocyst. It’s a microscopic clump of cells that looks as innocuous as a raspberry. … “These are fertilized cells that are alive,” says Paul McHugh, a professor of psychiatry and behavioral sciences at the School of Medicine.
Whereas Germany, Austria, Italy, Finland, Ireland, Portugal and the Netherlands prohibit or severely restrict the use of embryonic stem cells, Greece, Sweden, Spain and the United Kingdom have created the legal basis to support this research. Belgium bans reproductive cloning but allows therapeutic cloning of embryos.
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