In Search For Cures, Scientists Create Embryos That Are Both Animal And Human
A handful of scientists around the United States are trying to do something that some people find disturbing: make embryos that are part human, part animal.
The researchers hope these embryos, known as chimeras, could eventually help save the lives of people with a wide range of diseases.
One way would be to use chimera embryos to create better animal models to study how human diseases happen and how they progress.
Perhaps the boldest hope is to create farm animals that have human organs that could be transplanted into terminally ill patients.
But some scientists and bioethicists worry the creation of these interspecies embryos crosses the line. "You're getting into unsettling ground that I think is damaging to our sense of humanity," says Stuart Newman, a professor of cell biology and anatomy at the New York Medical College.
The experiments are so sensitive that the National Institutes of Health has imposed a moratorium on funding them while officials explore the ethical issues they raise.
Nevertheless, a small number of researchers are pursuing the work with private funding. They hope the results will persuade the NIH to lift the moratorium.
"We're not trying to make a chimera just because we want to see some kind of monstrous creature," says Pablo Ross, a reproductive biologist at the University of California, Davis. "We're doing this for a biomedical purpose."
The NIH is expected to announce soon how it plans to handle requests for funding.
Recently, Ross agreed to let me visit his lab for an unusual look at his research. During the visit, Ross demonstrated how he is trying to create a pancreas that theoretically could be transplanted into a patient with diabetes.
The first step involves using new gene-editing techniques to remove the gene that pig embryos need to make a pancreas.
Working under an elaborate microscope, Ross makes a small hole in the embryo's outer membrane with a laser. Next, he injects a molecule synthesized in the laboratory to home in and delete the pancreas gene inside. (In separate experiments, he has done this to sheep embryos, too.)
After the embryos have had their DNA edited this way, Ross creates another hole in the membrane so he can inject human induced pluripotent stem cells, or iPS for short, into the pig embryos.
Like human embryonic stem cells, iPS cells can turn into any kind of cell or tissue in the body. The researchers' hope is that the human stem cells will take advantage of the void in the embryo to start forming a human pancreas.
Because iPS cells can be made from any adult's skin cells, any organs they form would match the patient who needs the transplant, vastly reducing the risk that the body would reject the new organ.
But for the embryo to develop and produce an organ, Ross has to put the chimera embryos into the wombs of adult pigs. That involves a surgical procedure, which is performed in a large operating room across the street from Ross's lab.
The day Ross opened his lab to me, a surgical team was anesthetizing an adult female pig so surgeons could make an incision to get access to its uterus.
Ross then rushed over with a special syringe filled with chimera embryos. He injected 25 embryos into each side of the animal's uterus. The procedure took about an hour. He repeated the process on a second pig.
Every time Ross does this, he then waits a few weeks to allow the embryos to develop to their 28th day — a time when primitive structures such as organs start to form.
Ross then retrieves the chimeric embryos to dissect them so he can see what the human stem cells are doing inside. He examines whether the human stem cells have started to form a pancreas, and whether they have begun making any other types of tissues.
The uncertainty is part of what makes the work so controversial. Ross and other scientists conducting these experiments can't know exactly where the human stem cells will go. Ross hopes they'll only grow a human pancreas. But they could go elsewhere, such as to the brain.
"If you have pigs with partly human brains you would have animals that might actually have consciousness like a human," Newman says. "It might have human-type needs. We don't really know."
That possibility raises new questions about the morality of using the animals for experimentation. Another concern is that the stem cells could form human sperm and human eggs in the chimeras.
"If a male chimeric pig mated with a female chimeric pig, the result could be a human fetus developing in the uterus of that female chimera," Newman says. Another possibility is the animals could give birth to some kind of part-human, part-pig creature.
"One of the concerns that a lot of people have is that there's something sacrosanct about what it means to be human expressed in our DNA," says Jason Robert, a bioethicist at Arizona State University. "And that by inserting that into other animals and giving those other animals potentially some of the capacities of humans that this could be a kind of violation — a kind of, maybe, even a playing God."
Ross defends what his work. "I don't consider that we're playing God or even close to that," Ross says. "We're just trying to use the technologies that we have developed to improve peoples' life."
Still, Ross acknowledges the concerns. So he's moving very carefully, he says. For example, he's only letting the chimera embryos develop for 28 days. At that point, he removes the embryos and dissects them.
If he discovers the stem cells are going to the wrong places in the embryos, he says he can take steps to stop that from happening. In addition, he'd make sure adult chimeras are never allowed to mate, he says.
"We're very aware and sensitive to the ethical concerns," he says. "One of the reasons we're doing this research the way we're doing it is because we want to provide scientific information to inform those concerns."
Ross is working with Juan Carlos Izpisua Belmonte from the Salk Intitute for Biological Studies in La Jolla, Calif., and Hiromitsu Nakauchi at Stanford University. Daniel Garry of the University of Minnesota and colleagues are conducting similar work.
http://www.npr.org/sections/health-shots/2016/05/18/478212837/in-search-for-cures-scientists-create-embryos-that-are-both-animal-and-human
Audit Finds 'Hostile Probes,' Breaches of Weather Satellite System
The nation's weather satellite program over the course of a year suffered 10 data security incidents, including unauthorized access and probes by adversaries, according to a congressional auditor.
The $11.3 billion Joint Polar Satellite System is set to launch the program’s first next-gen spacecraft, the JPSS-1, in March 2017.
But the ground stations that handle satellite communications and data processing "remain at high risk of compromise," David Powner, the Government Accountability Office's director of IT management issues, said in a new report.
The satellite program, which is run by the National Oceanic and Atmospheric Administration, feeds prediction models and aids weather forecasters on the ground.
"NOAA has experienced several recent information security incidents regarding unauthorized access to Web servers and computers," Powner said in the audit, released Tuesday. The six episodes now considered closed matters "involved hostile probes, improper usage, unauthorized access, password sharing, and other IT-related security concerns."
On Wednesday, NOAA declined to provide more information due to national security.
"While NOAA cannot publicly comment on these specific incidents, due to reasons related to national security, all cyber security threats are taken seriously and addressed quickly. NOAA remains committed to maintaining the highest possible level of information security," agency spokesman John Leslie said in an emailed statement to Nextgov.
The Government Accountability Office had directed Nextgov to the agency for specifics, because of the sensitivity of the issue.
According to the audit, there is a discrepancy between the program office and agency incident response team over how many of the 10 cases have been handled fully.
Two of the four incidents the JPSS program office recommended be closed remain open. The NOAA incident response team ultimately is responsible for acting on the recommendation, according to the program office.
"Until NOAA and the JPSS program have a consistent understanding of the status of incidents, there is an increased risk that key vulnerabilities will not be identified or properly addressed," as well as "tracked to closure,” Powner said.
Agency officials told Powner work is underway on a new tool to improve the uniformity and timeliness of incident tracking.
The ground system is highly susceptible to compromise because, among other things, the agency has not executed nearly half of the recommended standard security controls and has not patched key vulnerabilities, the audit states.
As of August 2015, there were 1,400 critical and high-risk vulnerabilities that included outdated software, an obsolete Web server and old antivirus definitions. NOAA, which is part of the Commerce Department, is not scheduled to finish fixing the security holes until August of this year and January 2017.
By that time, the vulnerabilities will have been open to potential attack for between 17 and 22 months longer than required by the government, according to the audit.
Commerce Deputy Secretary Bruce Andrews, in a written response to the auditors, agreed with the findings but said “resource constraints and shifting priorities” have hampered efforts to keep pace with changing cybersecurity requirements and to avoid schedule slippages.
“We are responding to these challenges by working to establish repeatable processes and resilient information architecture that together enable mission achievement," he added.
NOAA is no stranger to network intrusions, like much of the federal government. Four agency websites were breached in fall 2014 by an Internet-based attack.
Then, Rep. Frank Wolf, R-Va., said NOAA told him the incident was tied to the Chinese government. In 2013, a hacker stole national environmental satellite data from a contractor's PC.
JPSS-1’s timely launch is critical to ensuring the agency's weather forecasts are accurate. NOAA’s current crop of joint polar-orbiting satellites are aging and have been running on borrowed time for years.
http://www.nextgov.com/cybersecurity/2016/05/audit-finds-hostile-probes-breaches-commerce-satellite-system/128393/
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