Some atheist scientists with children embrace religious traditions, according to new research

ScienceDaily (Dec. 1, 2011) — Some atheist scientists with children embrace religious traditions for social and personal reasons, according to research from Rice University and the University at Buffalo -- The State University of New York (SUNY).

The study also found that some atheist scientists want their children to know about different religions so their children can make informed decisions about their own religious preferences.

"Our research shows just how tightly linked religion and family are in U.S. society -- so much so that even some of society's least religious people find religion to be important in their private lives," said Rice sociologist Elaine Howard Ecklund, the study's principal investigator and co-author of a paper in the December issue of the Journal for the Scientific Study of Religion.

The researchers found that 17 percent of atheists with children attended a religious service more than once in the past year.

The research was conducted through interviews with a scientifically selected sample of 275 participants pulled from a survey of 2,198 tenured and tenure-track faculty in the natural and social sciences at 21 elite U.S. research universities. Approximately half of the original survey population expressed some form of religious identity, whereas the other half did not.

The individuals surveyed cited personal and social reasons for integrating religion into their lives, including:

Scientific identity -- Study participants wish to expose their children to all sources of knowledge (including religion) and allow them to make their own choices about a religious identity.Spousal influence -- Study participants are involved in a religious institution because of influence from their spouse or partner.Desire for community -- Study participants want a sense of moral community and behavior, even if they don't agree with the religious reasoning.

Ecklund said one of the most interesting findings was discovering that not only do some atheist scientists wish to expose their children to religious institutions, but they also cite their scientific identity as reason for doing so.

"We thought that these individuals might be less inclined to introduce their children to religious traditions, but we found the exact opposite to be true," Ecklund said. "They want their children to have choices, and it is more consistent with their science identity to expose their children to all sources of knowledge."

One study participant raised in a strongly Catholic home said he came to believe later that science and religion were not compatible. He said what he wants to pass on to his daughter -- more than the belief that science and religion are not compatible -- is the ability to make her own decisions in a thoughtful, intellectual way.

"I … don't indoctrinate her that she should believe in God," the study participant said. "I don't indoctrinate her into not believing in God." He said he sees himself as accomplishing this by exposing her to a variety of religious choices, including Christianity, Islam, Buddhism and others.

Ecklund said the study's findings will help the public better understand the role that religious institutions play in society.

"I think that understanding how nonreligious scientists utilize religion in family life demonstrates the important function they have in the U.S.," she said.

Ecklund is the author of "Science vs. Religion: What Scientists Really Think,"published by Oxford University Press last year.

The paper was co-authored by University at Buffalo SUNY sociologist Kristen Schultz Lee. A grant from the John Templeton Foundation and funding from Rice supported the research.

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Elaine Howard Ecklund, Kristen Schultz Lee. Atheists and Agnostics Negotiate Religion and Family. Journal for the Scientific Study of Religion, Volume 50, Issue 4, pages 728%u2013743, December 2011 DOI: 10.1111/j.1468-5906.2011.01604.x

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Stronger corn? Take it off steroids, make it all female

ScienceDaily (Nov. 30, 2011) — A Purdue University researcher has taken corn off steroids and found that the results might lead to improvements in that and other crops.

Burkhard Schulz, an assistant professor of horticulture and landscape architecture, wanted to understand the relationship between natural brassinosteroids -- a natural plant steroid hormone -- and plant architecture, specifically plant height. Schulz said corn could benefit by becoming shorter and sturdier, but the mechanisms that control those traits are not completely understood.

"It is essential to change the architecture of plants to minimize how much land we need to produce food and fuels," said Schulz, whose findings are published in the early online version of the Proceedings of the National Academy of Sciences. "If you can find a natural mutation or mechanism that gives you what you need, you are much better off than using transgenic techniques that could be difficult to get approval for."

Schulz found that when maize loses the ability to produce brassinosteroids, it becomes a dwarf, as he suspected. But another feature caught him off guard: The plants without the naturally occurring steroids could not make male organs -- they had kernels where the tassels should be.

That could be a cost-saving discovery for the seed industry. Hybrid seed producers must painstakingly remove the male pollen-producing tassels from each plant so that they do not pollinate themselves. Schulz said maize plants that produce only female organs would eliminate the detasseling step.

"This would be the perfect mutation for hybrid seed production," Schulz said. "There is no way these plants could produce pollen because they do not have male flowers."

Schulz used a multistep process to determine brassinosteroids' role in height and, later, sex determination. He wanted to ensure that light and the addition of gibberelic acid, a hormone that promotes cell growth and elongation, would not eliminate the dwarfism.

Schulz gathered known mutants of maize with short mesocotyls, the first node on a corn stalk. He suspected that even dwarf plants that produced brassinosteroids would have elongated mesocotyls if grown in the dark as they stretched for light, a trait typical of all brassinosteroid mutants. He also added gibberellic acid to the plants to ensure that a deficiency of that hormone was not causing the dwarfism.

The dwarf plants that did not grow in the dark or with the addition of the gibberellic acid were compared to regular maize plants that had been dwarfed by subjecting them to a chemical that disrupts the creation of brassinosteroids. Both exhibited short stalks with twisted leaves and showed the feminization of the male tassel flower.

Schulz then used information that was already known from the research plant Arabidopsis about genes that control brassinosteroid production. He found the same genes in the maize genome.

In the dwarf maize plants, those genes were mutated, disrupting the biosynthesis of the steroids. A chemical analysis showed that the compounds produced along the pathway of gene to steroid were greatly diminished in the maize dwarfs. Cloning of the gene revealed that an enzyme of the brassinosteroid pathway was defective in the mutant plants. A related enzyme in humans has been reported as essential for the production of the sex steroid hormone testosterone. Mutations in this enzyme in humans also resulted in feminization.

While Schulz expected brassinosteroids to affect plant height, he said he did not expect those steroids to affect sex determination.

"We don't know if this is a special case for corn or if this is generally the same in other plants," he said. "If it is the same in other plants, it should be useful for creating plants or trees in which you want only males or females."

Gurmukh Johal, a professor of botany and plant pathology and collaborator on the research, identified the mutant used in the research, nana plant1, years ago. He said better understanding the steroid-production pathways could be important to strengthening maize plants and increasing yields.

"Maize produces too much pollen and it actually wastes a lot of energy on that," Johal said. "This implies that by using this gene or the pathway it controls, we could manipulate the plants to improve their quality."

Schulz said he would look at other plants, such as sorghum, to determine if the same genes and pathways control sex determination and height.

The project was an international collaboration with George Chuck from the Plant Gene Expression Center at the University of California Berkeley, Shozo Fujioka of RIKEN Advanced Science Institute in Japan, Sunghwa Choe of Seoul National University in South Korea, and Devi Prasad Potluri of Chicago State University.

The National Science Foundation and the U.S. Department of Agriculture funded the research.

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The above story is reprinted from materials provided by Purdue University. The original article was written by Brian Wallheimer.

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Thomas Hartwig, George S. Chuck, Shozo Fujioka, Antje Klempien, Renate Weizbauer, Devi Prasad V. Potluri, Sunghwa Choe, Gurmukh S. Johal, Burkhard Schulz. Brassinosteroid Control of Sex Determination in Maize. Proceedings of the National Academy of Sciences, 2011

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Trail of 'stone breadcrumbs' reveals the identity of one of the first human groups to leave Africa

ScienceDaily (Nov. 30, 2011) — A series of new archaeological discoveries in the Sultanate of Oman, nestled in the southeastern corner of the Arabian Peninsula, reveals the timing and identity of one of the first modern human groups to migrate out of Africa, according to a research article published in the open-access journal PLoS ONE.

An international team of archaeologists and geologists working in the Dhofar Mountains of southern Oman, led by Dr. Jeffrey Rose of the University of Birmingham, report finding over 100 new sites classified as "Nubian Middle Stone Age (MSA)." Distinctive Nubian MSA stone tools are well known throughout the Nile Valley; however, this is the first time such sites have ever been found outside of Africa. According to the authors, the evidence from Oman provides a "trail of stone breadcrumbs" left by early humans migrating across the Red Sea on their journey out of Africa. "After a decade of searching in southern Arabia for some clue that might help us understand early human expansion, at long last we've found the smoking gun of their exit from Africa," says Rose. "What makes this so exciting," he adds, "is that the answer is a scenario almost never considered." These new findings challenge long-held assumptions about the timing and route of early human expansion out of Africa.

Using a technique called Optically Stimulated Luminescence (OSL) to date one of the sites in Oman, researchers have determined that Nubian MSA toolmakers had entered Arabia by 106,000 years ago, if not earlier. This date is considerably older than geneticists have put forth for the modern human exodus from Africa, who estimate the dispersal of our species occurred between 70,000 and 40,000 years ago. Even more surprising, all of the Nubian MSA sites were found far inland, contrary to the currently accepted theory that envisions early human groups moving along the coast of southern Arabia. "Here we have an example of the disconnect between theoretical models versus real evidence on the ground," says co-author Professor Emeritus Anthony Marks of Southern Methodist University. "The coastal expansion hypothesis looks reasonable on paper, but there is simply no archaeological evidence to back it up.

Genetics predict an expansion out of Africa after 70,000 thousand years ago, yet we've seen three separate discoveries published this year with evidence for humans in Arabia thousands, if not tens of thousands of years prior to this date." The presence of Nubian MSA sites in Oman corresponds to a wet period in Arabia's climatic history, when copious rains fell across the peninsula and transformed its barren deserts to sprawling grasslands. "For a while," remarks Rose, "South Arabia became a verdant paradise rich in resources -- large game, plentiful freshwater, and high-quality flint with which to make stone tools." Far from innovative fishermen, it seems that early humans spreading from Africa into Arabia were opportunistic hunters traveling along river networks like highways. Whether or not these pioneers were able to survive in Arabia during the hyperarid conditions of the Last Ice Age is another matter -- a mystery that will require archaeologists to continue combing the deserts of southern Arabia, hot on the trail of stone breadcrumbs.

The Dhofar Archaeological Project is conducted under the auspices of the Ministry of Heritage and Culture in Oman. The team is composed of an interdisciplinary group of researchers from the University of Birmingham and Oxford Brookes University, UK; Arizona State University and Southern Methodist University, USA; Institute of Archaeology, National Academy of Sciences, Ukraine; Institute of Archaeology of the Academy of Science, Czech Republic; University of Tübingen, Germany, and the University of Wollongong, Australia. The project is funded by research grants from the UK Arts and Humanities Research Council and the Australian Research Council.

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Jeffrey I. Rose, Vitaly I. Usik, Anthony E. Marks, Yamandu H. Hilbert, Christopher S. Galletti, Ash Parton, Jean Marie Geiling, Viktor Cerný, Mike W. Morley, Richard G. Roberts. The Nubian Complex of Dhofar, Oman: An African Middle Stone Age Industry in Southern Arabia. PLoS ONE, 2011; 6 (11): e28239 DOI: 10.1371/journal.pone.0028239

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Astronomers discover new exoplanet similar in size to Earth; Planet Kepler-21b found using space and ground-based observations

ScienceDaily (Nov. 30, 2011) — The NASA Kepler Mission is designed to survey a portion of our region of the Milky Way Galaxy to discover Earth-size planets in or near the "habitable zone," the region in a planetary system where liquid water can exist, and determine how many of the billions of stars in our galaxy have such planets. It now has another planet to add to its growing list.

A research team led by Steve Howell, of NASA's Ames Research Center, has shown that one of the brightest stars in the Kepler star field has a planet with a radius only 1.6 that of Earth's radius and a mass no greater that 10 Earth masses, circling its parent star with a 2.8-day period. With such a short period, and such a bright star, the team of over 65 astronomers -- which included David Silva, Ken Mighell and Mark Everett of the National Optical Astronomy Observatory (NOAO) -- needed multiple telescopes on the ground to support and confirm their Kepler observations. These included the 4-meter Mayall telescope and the WIYN telescope at Kitt Peak National Observatory.

With a period of only 2.8 days, this planet, designated Kepler-21b, is only about 6 million kilometers away from its parent star. By comparison Mercury, the closest planet to the sun, has a period of 88 days and a distance from the sun almost ten times greater, or 57 million km. So Kepler 21b is far hotter than any place humans could venture. The team calculates that the temperature at the surface of the planet is about 1900 K, or 2960 F. While this temperature is nowhere near the habitable zone in which liquid water might be found, the planet's size is approaching that of Earth.

The parent star, HD 179070, is quite similar to our sun: its mass is 1.3 solar masses, its radius is 1.9 solar radii, and its age, based on stellar models, is 2.84 billion years (or a bit younger than the sun's 4.6 billion years). HD 179070 is spectral type F6 IV, a little hotter and brighter than the sun. By astronomical standards, HD 179070 is fairly close, at a distance from the sun of 352 light years. While it cannot be seen by the unaided eye, a small telescope can easily pick it out.

Part of the difficulty in detecting this planet is the realization, from the Kepler mission, that many stars show short period brightness oscillations. The effect of these must be removed from the stellar light in order to uncover the regular, but very small, dimming caused by the planet passing in front of the star. The Kepler mission observed this field for over 15 months, and the team combined the observations to enable them to detect this tiny, periodic signal. They also relied on spectroscopic and imaging data from a number of ground based telescopes.

The results of this work have been accepted for publication in the Astrophysical Journal.

NOAO is operated by Association of Universities for Research in Astronomy Inc. (AURA) under a cooperative agreement with the National Science Foundation.

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Children with HIV/AIDS falling through the cracks of treatment scale-up efforts

ScienceDaily (Dec. 1, 2011) — Less than one-quarter (23%) of children with HIV/AIDS who need treatment are getting it, according to a report released by the World Health Organization (WHO) on the occasion of World AIDS Day (1 December 2011). Although treatment coverage for adults has been steadily climbing and has now reached approximately half of those in need, coverage for children is lagging far behind, highlighted the Drugs for Neglected Diseases initiative (DNDi), a non-profit research and development organization that has recently launched a new paediatric HIV drug development programme.

'Children with HIV/AIDS are falling through the cracks', said Dr Bernard Pécoul, Executive Director of the DNDi. '250,000 children died of HIV-related complications in 2010 -- that's nearly 700 each day. This is simply unacceptable.'

There are several reasons for this situation -- including lack of access for pregnant women to antenatal care, HIV testing, and antiretrovirals (ARVs) to prevent mother-to-child transmission and treat expecting mothers, as well as difficulties diagnosing HIV in infants. But one of the most important, and overlooked, is the lack of suitable formulations of ARVs adapted for children, particularly babies and toddlers. The reason for this neglect lies, ironically, with the success of the virtual elimination of HIV among newborns in wealthy countries.

'There's little profit to be made from developing treatments for the millions of children with HIV/AIDS, 90% of whom are the poorest of the poor in sub-Saharan Africa, and the lack of market incentive means pharmaceutical companies do not develop ARVs adapted to their needs', Dr Pécoul continued. 'Without treatment, half of the children born with HIV die before their second birthday.'

WHO recommends immediate ART for all HIV-positive children less than two years old, but the safety and correct dosing have not been established in very young children for the majority of ARVs approved for adults. In addition, key existing paediatric ARV formulations taste bad, require impractical multiple liquid preparations and refrigeration, and have undesirable interactions with tuberculosis (TB) drugs.

DNDi's new paediatric HIV programme aims to develop an improved first-line therapy for children under three years of age. Ideally, this ARV combination therapy needs to be easy to administer and better tolerated by children than current drugs, as well as heat stable and easily dispersible (dissolvable in water or breast milk). It must also carry minimal risk for developing resistance and require minimum weight adjustments. Finally, any new formulations must be compatible with TB drugs.

'Given the current funding crisis, we are deeply concerned that children with HIV/AIDS -- who are already invisible and largely voiceless -- will fall even further down on the agenda', said Dr Marc Lallemant, Head of DNDi's Paediatric HIV Programme. 'And while everything possible needs to be done to achieve the long-term goal of "eliminating" new infections among infants, including through scale-up of prevention of mother-to-child transmission programmes, a more serious response is urgently needed for HIV-positive children today.'

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Earthquake friction effect demonstrated at the nanoscale

ScienceDaily (Nov. 30, 2011) — Earthquakes are some of the most daunting natural disasters that scientists try to analyze. Though Earth's major fault lines are well known, there is little scientists can do to predict when an earthquake will occur or how strong it will be. And, though earthquakes involve millions of tons of rock, a team of University of Pennsylvania and Brown University researchers has helped discover an aspect of friction on the nanoscale that may lead to a better understanding of the disasters.

Robert Carpick, a professor who chairs the Department of Mechanical Engineering and Applied Mechanics in Penn's School of Engineering and Applied Science, led the research in collaboration with Terry Tullis and David Goldsby, professors of geological science at Brown. The experimental and modeling work was conducted by first author Qunyang Li, a postdoctoral researcher in Carpick's group, who has recently been appointed an associate professor in the School of Aerospace at Tsinghua University, China.

Their work will be published in the journal Nature.

The team's research was spurred by an unusual phenomenon that has been observed in both natural and laboratory-simulated faults: materials become more resistant to sliding the longer they are in contact with one another. This trait is actually fundamental to why earthquakes happen at all. The longer materials are in contact, the stronger the resistance between them and the more violent and unstable the subsequent sliding is. Energy is stored over the time the materials are in contact and is then catastrophically released as an earthquake.

While geologists, physicists and mechanics researchers have studied this phenomenon for decades, the mechanism behind this increase of friction over time has only been hypothesized. There are two main theories as to why this "frictional aging" occurs.

"One hypothesis is that points of contact deform and grow over time -- that contact quantity increases," Carpick said. "The other is that bonding at the points of contact strengthens over time -- that contact quality increases."

The difficulty in proving that either theory holds true lies in the fact that points of contact are necessarily embedded at the juncture of two materials and are therefore hard to observe. One of the original breakthrough experiments on these theories projected light through transparent materials held together to measure the growth of apparent contact points. While this lent credence to the contact quantity theory, there was not yet a way to assess the bond strengths at those individual points of contacts or to be sure that the observations were of single points of contacts or clusters of even smaller nanoscale contacts.

It was not until Carpick and Tullis met at a conference designed to bring physicists and mechanics researchers together with geologists that they realized that the tools of the former group could resolve the latter group's contact quality theory. The solution came from moving from the massive scale of earthquakes to the smallest scales imaginable.

"We want to simplify the case," Li said. "So in our experiment we look at only one point of contact: the tip of an atomic force microscope."

An atomic force microscope is an ideal tool for investigating bonding strength where two surfaces meet. Instead of using light, atomic force microscopes measure nanoscale details using an extremely sharp probe tip that is sensitive to the push and pull of individual atoms.

The researchers simulated rock-on-rock contact with silica, a major component in most geological materials. They pressed a silica tip against a silica surface for different lengths of time and then dragged it to measure the amount of friction it experienced. They repeated these experiments with surfaces made out of different materials: diamond and graphite. Critically, both diamond and graphite are chemically inert. As they don't easily form chemical bonds with silica, any frictional aging that occurred with them would necessarily be due to changing contact area and not increased bond strength.

The results showed a stark difference in the frictional aging between the materials.

"We saw a huge amount of aging with silica on silica. But with silica on diamond or graphite, even though the tip is experiencing about the same stress levels, we see almost no aging," Li said. "If the increasing contact area was responsible for the increase in frictional aging, you would see similar amounts in these cases. You might even see more aging with diamond because it is stiffer, leading to a slightly higher stress level in the silica, and this would cause more deformation on the tip."

The frictional aging seen in the silica-on-silica experiment was so intense that the researchers had another mystery on their hands: how to reconcile strong aging on the nanoscale with the weaker level seen on the macroscale where earthquakes actually occur.

The solution to that puzzle stems from the fact that not all contact points are created equal. Two different contact points on the same surface that are close to one another will sense each other's presence. This "elastic coupling," as it is known, means that only a few of the contact points within an area will be resisting the sliding motion at their full capacity; some will have started to slide earlier, and others will slide later. It is too difficult to make them all slide at once.

So, the overall level of resistance relies not only on the maximum resistance any contact point can provide, but also on the small fraction of contact points able to provide this resistance.

"When you take a lot of contact points,"Carpick said, "all of them could have this large amount of aging. But when you try to shear them, you see only a small fraction reach that very high value of friction at any given time. So, you need a very large effect on the level of a single contact point to get even a very modest effect on the macroscopic scale."

While showing that nansocale experiment can provide useful data for these kinds of applications was in itself an important finding for the research team, the ability to reconcile the laboratory data with geologists' observations will have a lasting effect on the field.

"If we can understand the fundamental physics," Tullis said, "then theories and equations based on that physics would have the capability of being extrapolated beyond the laboratory scale. Therefore we could use them with more confidence in all the earthquake modeling that's already being done."

"We're not ruling out the quantity argument, we're just ruling in the quality argument," Carpick said. "Future research will go to higher stress levels, where maybe contact quantity could start to come into play. We'd also like to look at different temperatures, which matter in the geological context, and do experiments where we can actually watch the contact in real time, using an electron microscope."

The research was supported by the National Science Foundation.

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Qunyang Li, Terry E. Tullis, David Goldsby, Robert W. Carpick. Frictional ageing from interfacial bonding and the origins of rate and state friction. Nature, 2011; DOI: 10.1038/nature10589

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Biologists deliver neutralizing antibodies that protect against HIV infection in mice

ScienceDaily (Nov. 30, 2011) — Over the past year, researchers at the California Institute of Technology (Caltech), and around the world, have been studying a group of potent antibodies that have the ability to neutralize HIV in the lab; their hope is that they may learn how to create a vaccine that makes antibodies with similar properties. Now, biologists at Caltech led by Nobel Laureate David Baltimore, president emeritus and Robert Andrews Millikan Professor of Biology, have taken one step closer to that goal: they have developed a way to deliver these antibodies to mice and, in so doing, have effectively protected them from HIV infection.

This new approach to HIV prevention -- called Vectored ImmunoProphylaxis, or VIP -- is outlined in the November 30 advance online publication of the journal Nature.

Traditional efforts to develop a vaccine against HIV have been centered on designing substances that provoke an effective immune response -- either in the form of antibodies to block infection or T cells that attack infected cells. With VIP, protective antibodies are being provided up front.

"VIP has a similar effect to a vaccine, but without ever calling on the immune system to do any of the work," says Alejandro Balazs, lead author of the study and a postdoctoral scholar in Baltimore's lab. "Normally, you put an antigen or killed bacteria or something into the body, and the immune system figures out how to make an antibody against it. We've taken that whole part out of the equation."

Because mice are not sensitive to HIV, the researchers used specialized mice carrying human immune cells that are able to grow HIV. They utilized an adeno-associated virus (AAV) -- a small, harmless virus that has been useful in gene-therapy trials -- as a carrier to deliver genes that are able to specify antibody production. The AAV was injected into the leg muscle of mice, and the muscle cells then put broadly neutralizing antibodies into the animals' circulatory systems. After just a single AAV injection, the mice produced high concentrations of these antibodies for the rest of their lives, as shown by intermittent sampling of their blood. Remarkably, these antibodies protected the mice from infection when the researchers exposed them to HIV intravenously.

The team points out that the leap from mice to humans is large -- the fact that the approach works in mice does not necessarily mean it will be successful in humans. Still, the researchers believe that the large amounts of antibodies that the mice were able to produce -- coupled with the finding that a relatively small amount of antibody has proved protective in the mice -- may translate into human protection against HIV infection.

"We're not promising that we've actually solved the human problem," says Baltimore. "But the evidence for prevention in these mice is very clear."

The paper also notes that in the mouse model, VIP worked even in the face of increased exposure to HIV. To test the efficacy of the antibody, the researchers started with a virus dose of one nanogram, which was enough to infect the majority of the mice who received it. When they saw that the mice given VIP could withstand that dose, they continued to bump it up until they were challenging them with 125 nanograms of virus.

"We expected that at some dose, the antibodies would fail to protect the mice, but it never did -- even when we gave mice 100 times more HIV than would be needed to infect 7 out of 8 mice," says Balazs. "All of the exposures in this work were significantly larger than a human being would be likely to encounter."

He points out that this outcome likely had more to do with the properties of the antibody that was tested than the method, but adds that VIP is what enabled the large amount of this powerful antibody to circulate through the mice and fight the virus. Furthermore, VIP is a platform technique, meaning that as more potent neutralizing antibodies are isolated or developed for HIV or other infectious organisms, they can also be delivered using this method.

"If humans are like mice, then we have devised a way to protect against the transmission of HIV from person to person," says Baltimore. "But that is a huge if, and so the next step is to try to find out whether humans behave like mice."

He says the team is currently in the process of developing a plan to test their method in human clinical trials. The initial tests will ask whether the AAV vector can program the muscle of humans to make levels of antibody that would be expected to be protective against HIV.

"In typical vaccine studies, those inoculated usually mount an immune response -- you just don't know if it's going to work to fight the virus," explains Balazs. "In this case, because we already know that the antibodies work, my opinion is that if we can induce production of sufficient antibody in people, then the odds that VIP will be successful are actually pretty high."

The study, "Antibody-based Protection Against HIV Infection by Vectored ImmunoProphylaxis," was funded by the Bill and Melinda Gates Foundation, the National Institutes of Health, and the Caltech-UCLA Joint Center for Translational Medicine. Caltech biology researchers Joyce Chen, Christin M. Hong, and Lili Yang also contributed to the paper, as well as Dinesh Rao, a hematologist from the University of California, Los Angeles.

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Alejandro B. Balazs, Joyce Chen, Christin M. Hong, Dinesh S. Rao, Lili Yang, David Baltimore. Antibody-based protection against HIV infection by vectored immunoprophylaxis. Nature, 2011; DOI: 10.1038/nature10660

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