Las Vegas Sun

March 28, 2024

Breakthrough stemmed

A potential breakthrough in embryonic stem cell research that could have great benefits in Nevada has been called into question because misleading information about the technology appeared in media outlets across the country.

Advanced Cell Technology researchers wrote in the scientific journal Nature that they had developed a method of making embryonic stem cells while maintaining viable embryos. Supporters touted the discovery as a way to remove many ethical concerns voiced by opponents of stem cell use.

The results were called into question, however, when it was revealed the embryos used in the experiment were, in fact, destroyed.

Researchers at Massachusetts-based Advanced Cell Technology said they knew the embryos would not survive because several cells from each embryo were used in the experiments to increase the chance for success.

They maintain, however, that the principle behind the research is sound because it demonstrates a single cell taken from an embryo can produce viable stem cell lines. Embryos with only one cell removed have resulted in hundreds of live births through in vitro fertilization.

The setback was disheartening to researchers across the Silver State who had hoped the technology might fuel support for more widespread use of embryonic stem cells, which they say could lead to medical breakthroughs.

Dr. Esmail Zanjani, chairman of UNR's animal biotechnology department, is researching before-birth treatments on diseases such as sickle-cell anemia and hemophilia. He uses human stem cells and sheep fetuses to generate the cells needed to correct diseases.

He says the limited availability of stem cells has been a major stumbling block: "We are limited to using the human embryonic stem cells that have been approved by the government. These cells have been around a long time and have been continuously expanded. They are not the pristine source of cells they once were, and that's really a drawback."

There are private sources for stem cells, but Zanjani says suppliers of those cells have a specific goal in mind, which limits the research potential.

He already has developed a stem cell technique that cured the immune deficiency or "bubble boy" disease before birth by using bone marrow transplants.

The potential for stem cells goes far beyond this, he says: "The main thrust of our work is to figure out what human stem cells can do once they get inside the body. Human embryonic stem cells produce all kinds of specialized cells in culture, but once transferred inside an animal they don't do anything."

By transferring the cells into a newly developed animal fetus, the cells are not rejected, and Zanjani believes they can develop enough characteristics of human organs to be used in transplants. The potential for this research to the more than 90,000 people in this country awaiting organ transplants, 7,000 of whom die each year before they get one, is clear.

Closer to home, the University of Nevada School of Medicine in Las Vegas and its Lou Ruvo Alzheimer's Institute could also benefit greatly from increased stem cell availability.

Dr. Charles Bernick is chief of neurology at the school and the institute's medical director. In addition to Alzheimer's disease, he says the institute treats Parkinson's, Lou Gehrig's Disease (amyotrophic lateral sclerosis or ALS) and Huntington's disease, and embryonic stem cell research has potential benefits for all of them.

"There are, for example, in Parkinson's and Alzheimer's, certain families where the disease is due to a genetic mutation," Bernick says. "The potential is there for stem cells to have value in recognizing the genetic mutation that causes the disease."

There are also preliminary indications that stem cells injected into the brain could change into the type of cell needed by Parkinson's patients. The decline of such patients is brought on by the loss of brain cells that produce dopamine, a messenger chemical.

Researchers admit that embryonic stem cells may not be the panacea everyone hopes, but they would at least like the opportunity to find out.

"Many in the scientific fields simply believe you have to have the ability to at least test the potential," says Bernick.

The method that has spurred the current controversy involves taking a cell from an eight cell-stage embryo produced for in vitro fertilization. The cell is allowed to grow overnight, creating new cells that are used to produce the stem cell lines.

The cell used in the successful test produced 19 stem cell outgrowths and two stable cell lines that were genetically normal and retained the potential to form all of the cells in the human body.

Previously, when a cell was removed from the embryo it was used for pre-implantation genetic testing. This method simply delays that testing long enough for the cell to grow.

Dr. Yupo Ma of the Nevada Cancer Institute in Summerlin had hoped the new method would gain widespread support and expand other research opportunities. Ma is working with adult stem cells to develop a technique that attacks the root of a leukemia tumor.

"In order to design a better therapy to target leukemia stem cells, we must better understand how leukemia stem cells are regulated," Ma says. "It will affect us if the federal government relaxes the rules regarding stem cell research."

Ma adds that the current federal policy hampers new embryonic stem cell research and has put U.S. scientists behind their European counterparts.

White House response to the use of embryonic stem cells has been less enthusiastic than many had hoped. President Bush this summer used the first veto of his presidency to block the use of federal funds for embryonic stem cell research.

Even before it was revealed that the embryos in the controversial tests were destroyed, Bush said the new method, if successful, would not resolve the ethical concerns raised when embryos are used.

Ronald Green, director of the Ethics Institute at Dartmouth College in New Hampshire and chairman of Advanced Cell Technology's ethics advisory board, disagrees.

"One of the major ethical objections of those who oppose the generation of human embryonic stem cells is that all techniques have resulted in the destruction of the embryo. This technique has the potential to overcome that hurdle," he says.

Another question with this method concerns the potential for damage to the embryo from which the cell is taken even if the embryo could be preserved. Green admits that taking a cell from a healthy embryo poses some risk. He points out, however, that more than 2,000 babies have been born from embryos with a cell removed for genetic testing.

Senate Minority Leader Harry Reid, D-Nev., has been an outspoken supporter of stem cell research. He expressed concerns that questions about the new technology could be an additional roadblock to research.

"I am disappointed that, as thousands of Nevadans are suffering, the president continues to hinder promising research like this that could clear the way for a wide range of diseases and conditions," he says.

"It's time for a new direction, one that believes in science and the hope that stem cell research brings."

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