Thursday, November 15, 2007

Major newspapers report on Oregon stem cell work

Further to a discussion by The Independent on November 11, major newspapers are now reporting the "monkey cloning" story. The Los Angeles Times says:

After years of false starts and an international scientific scandal, researchers said Wednesday [Nov. 14] that they had achieved a feat that some scientists believed was impossible -- cloning a monkey embryo from a skin cell of an adult and using it to harvest embryonic stem cells.

Scientists have previously cloned embryos and adult animals of a variety of species, including rats, dogs and cattle. But primates -- the family that includes monkeys and humans -- have proved remarkably resistant to the most sophisticated techniques in the cloner's arsenal.

Reproductive biologist Shoukhrat Mitalipov of Oregon Health & Science University and his colleagues reported in the online version of the journal Nature that they had successfully cloned rhesus macaque embryos using DNA from skin cells taken from the ear of a 9-year-old male. The resulting stem cells grew into viable heart and nerve cells, among others.

"This is a giant step toward showing that human therapeutic cloning is possible," said Dr. Robert Lanza, an embryonic stem cell researcher at Advanced Cell Technology in Worcester, Mass., who was not involved in the research. "It proves once and for all that primate cloning is not impossible . . . as many people had thought."

One can only wonder about the accuracy of the line "It proves once and for all that primate cloning is not impossible . . . as many people had thought" in light of the ready acceptance by stem cell workers of Hwang's false claims about human SCNT [somatic cell nuclear transfer] in the years 2004 and 2005.

The Times article got into issues with SCNT:

The team of researchers, from Oregon and the University of Nebraska Medical Center, used a technique called somatic cell nuclear transfer, in which genetic material from a somatic cell -- any cell other than a sperm or egg -- is transferred into the nucleus of an unfertilized egg.

The problem is that the DNA from the donor is not at the same stage of life as the material in the egg, and getting the two into rhythm can be difficult.

The process has been likened to a ballroom dance in which one partner starts on the beat while the second starts on the off-beat, destroying the rhythmic flow.

In terms of Jeanne Loring's arguments against the Thomson / WARF patents on the basis that "knowing about mice yields an obvious recipe for humans," note the following text:

Each species studied has required its own set of technical modifications to coax the two cellular constituents into step.

In many species, for example, researchers use dyes to see the part of the cell that holds the DNA in place. Mitalipov concluded that the stains were impeding the cloning process in primates and developed a technique using polarized light that avoided the problem.

They also discovered a variety of other technical tricks, including removing calcium and magnesium from the medium in which the cells were grown.

Gina Kolata of the New York Times was more direct about the lack of a mouse / human correlation:

In previous attempts, the investigators had used a method that worked well in mice. They marked the egg’s chromosomes with a dye that glowed under ultraviolet light. That let them see the chromosomes and be sure that they were removed before they inserted the adult cell with its genes into the egg.

The dye and ultraviolet light, the researchers surmised, might damage the egg. So they used a new method that shines polarized light through the egg, allowing them to see the chromosomes directly, without dyes.

Note a quote within the LA Times article:

This study is "really a combination of refinements of technologies that results in a better end result," said Paul J. Simmons, director of the Center for Stem Cell Biology at the University of Texas Health Science Center in Houston, who was not involved in the research.

Gina Kolata of the NYT also stated:

An advantage of using cloning to obtain stem cells is that they would genetically match a patient’s cells, making it unnecessary to suppress the immune system if the stem cells are used in treatment. Cloning could also produce stem cells that genetically match patients with complex diseases like Alzheimer’s. That might let scientists study those cells and understand how the diseases progress.

With the monkey work, some researchers say, cloned human embryonic stem cells seem more feasible. There is no way to know, of course, whether it will be harder or easier to repeat the work with humans. “I’m very enthusiastic,” said Dr. Leonard Zon, director of the stem cell program at Harvard’s Children’s Hospital. “The next step is definitely doing it in humans.”

[In passing, as of 10:30am (eastern) Nov. 15, californiastemcellreport still has not reported on the Oregon work which work is an obvious "plus" for stem cell workers/advocates. Asleep at the switch?]


Incredibly, californiastemcellreport (as of about 5:30pm) still has not mentioned the Oregon work. HOWEVER, there is a November 15 post at the report titled:

Celebrity Leeza Gibbons Named as CIRM Director

In this case, californiastemcellreport can be judged BOTH by what it didn't say AND by what it did say.


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