Researchers Advance Cloning Of Human Embryos

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Researchers in New York are reporting an advance in creating cloned human embryos. The embryos would not be used for reproduction, but rather for the creation of embryonic stem cells. Many scientists believe that human embryonic stem cells made this way could revolutionize medicine.

The advantage of stem cells made this way is that they could be personalized to an individual.

[Egli's work] isn't the gold ring, but it's a major step forward.

- George Daley, stem-cell researcher, Children's Hospital Boston

Think of it this way: Let's say you know you're going in for surgery in a few months to have your hip replaced. The surgeon says you may lose blood during the surgery, and recommends that you donate a pint of your own blood in advance in case you need it during the operation.

The advantage of donating your own blood is that there's no chance your immune system will reject that blood if it's put back into you.

Cloning, or somatic cell nuclear transfer, as scientists prefer to call it, is a technique that allows you to make what is essentially a genetic copy of a living organism. Stem cells derived from a cloned embryo are made with one of your stem cells but will be genetic twins to all the cells in your body, so receiving a stem-cell transplant would essentially mean getting your own cells back.

Dieter Egli and his colleagues at the New York Stem Cell Foundation have taken an important step toward that goal.

First they took an egg, removed its genetic material, replaced it with the genetic material from an adult skin cell, and coaxed the resulting embryo to grow. This is basically the same technique Scottish scientists used to create the first cloned mammal, Dolly the sheep. (See the top path in the illustration below.)

But Egli says that just because something works in some mammals doesn't mean it necessarily has to translate to human cells. And as others have found in the past, embryos made this way wouldn't grow.

Then Egli modified the Dolly technique. He left in the egg's genetic material instead of removing it, and then added the genetic material from the adult cell. That did the trick. The embryo started growing. (See the bottom path in the illustration below.)

Nature

In a first attempt (top), researchers removed an egg's genetic material and replaced it with the genes from an adult skin cell. These embryos didn't grow. The researchers tried another method: They left the egg's original genetic material in, but then also added genetic material from an adult cell (bottom). These embryos started growing.

But there was a problem.

Leaving in the egg's DNA meant each cell in the embryo now had three sets of chromosomes, instead of the two that are normally there. Transplanting stem cells derived from these embryos as a medical therapy wouldn't work. Our bodies just wouldn't know what to do with three sets of chromosomes.

Nature

This image shows the chromosomes from one of the cloned cells. Notice there are three sets of each chromosome; normal cells have just two copies of each chromosome.

But at least Egli has answered the question of whether it's possible to make a cloned human embryo. "The clear answer of our paper to this is yes, and this is really the major finding of the paper," he says.

Egli says this result gives him the confidence to keep working with their approach, to see if they can make it work with just the two chromosomes that are supposed to be there.

"[Egli's work] isn't the gold ring, but it's a major step forward, says stem-cell researcher George Daley, who works at Children's Hospital in Boston.

But even if Egli perfects his cloning techniques, there are still many people morally opposed to this kind of research. Daley says a new kind of cell, called an iPS cell, may prove to be just as good as an embryonic stem cell, and iPS cells can be made without eggs or embryos.

"The jury is still out as to whether the iPS cells are going to be the gold standard in the long run. In the near term, it's still the embryo-derived stem cells," says Daley. So for now, he thinks work with cloned human embryos should continue.

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Researchers Advance Cloning Of Human Embryos

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Researchers in New York are reporting an advance in creating cloned human embryos. The embryos would not be used for reproduction, but rather for the creation of embryonic stem cells. Many scientists believe that human embryonic stem cells made this way could revolutionize medicine.

The advantage of stem cells made this way is that they could be personalized to an individual.

[Egli's work] isn't the gold ring, but it's a major step forward.

- George Daley, stem-cell researcher, Children's Hospital Boston

Think of it this way: Let's say you know you're going in for surgery in a few months to have your hip replaced. The surgeon says you may lose blood during the surgery, and recommends that you donate a pint of your own blood in advance in case you need it during the operation.

The advantage of donating your own blood is that there's no chance your immune system will reject that blood if it's put back into you.

Cloning, or somatic cell nuclear transfer, as scientists prefer to call it, is a technique that allows you to make what is essentially a genetic copy of a living organism. Stem cells derived from a cloned embryo are made with one of your stem cells but will be genetic twins to all the cells in your body, so receiving a stem-cell transplant would essentially mean getting your own cells back.

Dieter Egli and his colleagues at the New York Stem Cell Foundation have taken an important step toward that goal.

First they took an egg, removed its genetic material, replaced it with the genetic material from an adult skin cell, and coaxed the resulting embryo to grow. This is basically the same technique Scottish scientists used to create the first cloned mammal, Dolly the sheep. (See the top path in the illustration below.)

But Egli says that just because something works in some mammals doesn't mean it necessarily has to translate to human cells. And as others have found in the past, embryos made this way wouldn't grow.

Then Egli modified the Dolly technique. He left in the egg's genetic material instead of removing it, and then added the genetic material from the adult cell. That did the trick. The embryo started growing. (See the bottom path in the illustration below.)

Nature

In a first attempt (top), researchers removed an egg's genetic material and replaced it with the genes from an adult skin cell. These embryos didn't grow. The researchers tried another method: They left the egg's original genetic material in, but then also added genetic material from an adult cell (bottom). These embryos started growing.

But there was a problem.

Leaving in the egg's DNA meant each cell in the embryo now had three sets of chromosomes, instead of the two that are normally there. Transplanting stem cells derived from these embryos as a medical therapy wouldn't work. Our bodies just wouldn't know what to do with three sets of chromosomes.

Nature

This image shows the chromosomes from one of the cloned cells. Notice there are three sets of each chromosome; normal cells have just two copies of each chromosome.

But at least Egli has answered the question of whether it's possible to make a cloned human embryo. "The clear answer of our paper to this is yes, and this is really the major finding of the paper," he says.

Egli says this result gives him the confidence to keep working with their approach, to see if they can make it work with just the two chromosomes that are supposed to be there.

"[Egli's work] isn't the gold ring, but it's a major step forward, says stem-cell researcher George Daley, who works at Children's Hospital in Boston.

But even if Egli perfects his cloning techniques, there are still many people morally opposed to this kind of research. Daley says a new kind of cell, called an iPS cell, may prove to be just as good as an embryonic stem cell, and iPS cells can be made without eggs or embryos.

"The jury is still out as to whether the iPS cells are going to be the gold standard in the long run. In the near term, it's still the embryo-derived stem cells," says Daley. So for now, he thinks work with cloned human embryos should continue.

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Initially, Daniel Shechtman's discovery cost him a job and the respect of his colleagues.

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Guy Raz talks with Insoo Hyun, associate professor of bioethics at Case Western Reserve University.

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Roche, Genentech researchers avoid business talk

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By Ransdell Pierson

NEW YORK | Fri Sep 23, 2011 5:34pm EDT

NEW YORK (Reuters) - When scientists at Genentech and parent Roche need to discuss business, they do not talk to each other -- they use lawyers.

Roche acquired the remaining stake of Genentech it did not already own in 2009, against the protests of critics who feared the cancer-drug powerhouse would lose the innovation prowess that made it the envy of the biotech world if it was absorbed by far-bigger Roche Holding AG.

But Roche research chief Jean-Jacques Garaud says the creative fires are burning as bright as ever at Genentech, which developed blockbuster cancer drugs Avastin and Herceptin, because it has been kept apart from Roche proper.

An estimated 2,500 scientists and research staff from Genentech work at its longtime campus in South San Francisco, in their own unit named gRED (Genentech Research and Early Development). They are charged with discovering drugs relating to cancer, immunology, neuroscience and infectious diseases.

In a seemingly parallel universe thousands of miles away in Europe, Shanghai and at a U.S. campus in New Jersey, Roche operates its own separate research unit with 3,000 researchers, called pRED (Pharma Research and Early Development), that specializes in the same disease areas and also is involved from drug discovery through mid-stage human trials.

"At the time we decided to bring Genentech on board it became obvious to us we had to keep separate the two units to keep the innovation alive," said Garaud, who heads pRED and its roster of Roche veterans.

"If you bring the units together, you contaminate each other -- you don't look at things differently. Innovation comes from groups looking at the same issue from different approaches. We want to have a diversity of approaches and maintain it," Garaud said in an interview.

"We talk to each other, but we don't talk about science too much. We talk about life -- books and movies."

Asked how the two units avoid duplicating research efforts if they do not talk business, he said that is where the attorneys come in.

"We are aware of duplication when it occurs because our patent lawyers are watching us and tell us if we are overlapping in activity -- if we are wasting resources on the same activity."

Garaud said it is too early to tell just how productive the respective research units will be, but noted that seven Roche drugs have progressed into late-stage trials since the Genentech deal.

"That is a strong success rate," he added.

(Reporting by Ransdell Pierson; editing by Andre Grenon)

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Zebra And Cattle Make Good Lunch Partners, Researchers Say

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Enlarge Ryan Lee Sensenig/Science

Cattle and zebra share a meal in a pasture in Kenya.

Ryan Lee Sensenig/Science Cattle and zebra share a meal in a pasture in Kenya.

Those of us who eat beef can thank cattle for turning grass into something tastier. But grass is not always easy to come by, especially in Africa. And without grass, where's the beef?

That's a big deal in Africa, where there's something of a range war going on — cattle versus just about any other grazers running wild: Oryx, buffalo, hartebeest, gazelle, and especially zebra. Conventional wisdom is that the wildlife eat the grass out from under the cattle. So some people shoot the wildlife, which is one reason wildlife numbers are crashing in much of the continent.

But some researchers who've spent the last 17 years watching cattle eat grass say, Don't squeeze the trigger so fast. (Yes, watching cattle eat grass takes dedication, especially when you have to weigh them in the field).

 

Ecologist Wilfred Odadi of the African Wildlife Foundation says he and his colleagues found that when cattle grazed shoulder to shoulder with zebra, the cattle actually gained more weight than when they dined alone. No doubt they also had more fun, zebras being somewhat more frolicsome than cows.

Here's why zebra make good dining companions: In the wet season, grass grows fast and soon gets tall and "rank." Basically, it gets fibrous and unappetizing to cows, says Truman Young, an ecologist at University of California at Davis. He's a grass guy; when he looks at a cow, he actually sees grass.

"What the zebra do is, they lop that (shoot) off," he says. "That encourages the regrowth of fresh shoots from the base, and those fresh shoots are just more edible. It's like having the choice of having bran muffins or blueberry muffins, I guess."

But, a note of caution. It only works this way in the wet season. In the dry season it's dog eat dog — and the zebras do eat the cattle's lunch.

Still, scientists say the research, which appears in the journal Science today, could help ranchers manage cattle and wildlife together, to their mutual benefit. And it might even work in the U.S.

Johan du Toit, an ecologist at Utah State University, is trying the same experiment with cattle and wildlife in the Utah plains – you know, where the buffalo roam, and the deer and the antelope play. His encouraging word: "It's worth a try."

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HEALTH MANAGEMENT. Researchers examine more recent and secure birth control method

Oregon Health & Science University researchers have discovered a new contraceptive, which is better, more secure and thus a larger population of women available. The research found the OHSU Oregon National Primate Research Center. It is published online in the journal Endocrinology.
Today's birth control methods are several decades old. The food and drug approved administration, for example, "the pill", 1961. It prevents contraception due to increase in the hormone levels of synthetic hormones. This higher hormone levels interrupt the normal menstrual cycle. In short, the synthetic hormones inhibit the release of hormones, responsible for triggering ovulation.
"While the method works, it its disadvantages", said ONPRC scientist Jon Hennebold, PhD. "The main concern is that through a stronger hormone levels, this contraceptive method affects systems in the body of a woman." "Therefore, there are some risks associated with current contraceptive methods, especially heart-cardiovascular disease."
An additional drawback is that hormonal treatments such as the pill of the user of schedule must comply with drugs. Due to this requirement the pill is only about 80 to 90 percent effective.
In contrast, the contraceptive are OHSU researchers develop, is not hormonal and more focused on mechanisms that directly lead the release an egg. This new approach is aimed at the major enzymes responsible for the release of an egg. Hennebold and his colleagues were able to determine exactly what enzymes to focus through the study of rhesus monkeys, which have a very similar reproductive system to humans.
This research in monkeys showed that on these enzymes the release of an egg from the ovary can prevent. The next step for Hennebold and colleagues is the delivery method to determine such drugs and the schedule for drugs.
"Our hope is that the next generation of birth control is targeted and more effective has" Hennebold added. "Much more work is necessary our proposed solution, further, but we believe that better, safe contraceptives are possible."

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