Predator-Prey Interaction Recreated In A Petri Dish

The hunter-versus-hunted phenomenon exemplified by a pack of lionesses chasing down a lonely gazelle has been recreated in a Petri dish with lowly bacteria.

Working with colleagues at Caltech, Stanford and the Howard Hughes Medical Institute, a Duke University bioengineer has developed a living system using genetically altered bacteria that he believes can provide new insights into how the population levels of prey influence the levels of predators, and vice-versa.

The Duke experiment is an example of a synthetic gene circuit, where researchers load new “programming” into bacteria to make them perform new functions. Such re-programmed bacteria could see a wide variety of applications in medicine, environmental cleanup and biocomputing. In this particular Duke study, researchers rewrote the software of the common bacteria Escherichia coli (E. coli.) to form a mutually dependent living circuit of predator and prey.

The bacterial predators don’t actually eat the prey, however. The two populations control each others’ suicide rates.

“We created a synthetic ecosystem made up of two distinct populations of E. coli, each with its own specific set of programming and each with the ability to affect the existence of the other,” said Lingchong You, assistant professor of biomedical engineering at Duke’s Pratt School of Engineering and member of Duke’s Institute for Genome Sciences and Policy. “This ecosystem is quite similar to the traditional predator-prey relationship seen in nature and may allow us to explore the dynamics of interacting populations in a predictable manner.”

The results of You’s study appear April 15 in the journal Molecular Systems Biology. The research was supported by National Institutes of Health, the Defense Advanced Research Projects Agency, the Howard Hughes Medical Institute, and the David and Lucile Packard Foundation.

This field of study, known as synthetic biology, emerged on the scientific scene around 2000, and many of the systems created since have involved the reprogramming of single bacteria. The current circuit is unique in that two different populations of reprogrammed bacteria live in the same ecosystem and are dependent on each other for survival.

“The key to the success of this kind of circuit is the ability of the two populations to communicate with each other,” You said. “We created bacteria representing the predators and the prey, with each having the ability to secrete chemicals into their shared ecosystem that can protect or kill.”

Central to the operation of this circuit are the numbers of predator and prey cells relative to each other in their controlled environment. Variations in the number of cells of each type trigger the activation of the reprogrammed genes, stimulating the creation of different chemicals.

In this system, low levels of prey in the environment cause the activation of a “suicide” gene in the predator, causing them to die. However, as the population of prey increases, it secretes into the environment a chemical that, when it achieves a high enough concentration, stimulates a gene in the predator to produce an “antidote” to the suicide gene. This leads to an increase in predators, which in turn causes the predator to produce another chemical which enters the prey cell and activates a “killer” gene, causing the prey to die.

“This system is much like the natural world, where one species – the prey – suffers from growth of another species – the predator,” You said. “Likewise, the predator benefits from the growth of the prey.”

This circuit is not an exact representation of the predator-prey relationship in nature because the prey stops the programmed suicide of predator instead of becoming food, and both populations compete for the same “food” in their world. Nevertheless, You believes that the circuit will become a useful tool for biologic researchers.

“This system provides clear mapping between genetics and the dynamics of population change, which will help in future studies of how molecular interactions can influence population changes, a central theme of ecology,” You said. “There are literally unlimited ways to change variables in this system to examine in detail the interplay between environment, gene regulation and population dynamics.

“With additional control over the mixing or segregating of different populations, we should be able to program bacteria to mimic the development and differentiation of more complex organisms,” he said.

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The research is a collaboration between the You lab and the laboratories of Frances Arnold at Caltech and Stephen Quake at Stanford and the Howard Hughes Medical Institute. The first author of the study, Frederick Balagadde, is currently establishing a research program at the Lawrence Livermore National Lab. While working in the Quake lab, he developed the technology to enable high-resolution measurements of the circuit dynamics. Other study authors include Duke’s Hao Song and Jun Ozaki, as well as Cynthia Collins, Rensselear Polytechnic Institute and Mat Barnet, Caltech.

Source: Richard Merritt

Duke University

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Global Fund Board Selects New Executive Director

The board of the Global Fund To Fight AIDS, Tuberculosis and Malaria has selected Michel Kazatchkine — France’s global ambassador for HIV/AIDS and communicable diseases and a former Global Fund vice chair — to serve as the organization’s new executive director, spokesperson Jon Liden said on Thursday, the AP/International Herald Tribune reports (AP/International Herald Tribune, 2/8). The Global Fund in November 2006 called off plans to name a new executive director to succeed Richard Feachem — whose contract ends in March — and launched a new search. Board members at closed meetings in November 2006 were unable to agree on one of two finalists. At that time, the final two candidates were Kazatchkine and Michel Sidibe, director of UNAIDS’ country and regional support department, according to meeting participants. Sidibe withdrew his candidacy for the position. According to a previous report, a nomination committee in January named nine candidates for the executive direction position. Three final candidates were named last month (Kaiser Daily HIV/AIDS Report, 1/31). The board’s official vote tally is not immediately available, Liden said, adding that Kazatchkine received the two-third majority required for approval (AP/International Herald Tribune, 2/8). “I look forward to handing over a strong institution that is positively impacting tens of millions of lives in 136 countries,” Feachem said, adding, “Under Dr. Kazatchkine’s leadership, the Global Fund is in excellent hands and its life saving work will continue to expand.” Carol Jacobs, chair of the Global Fund board, said, “This is a new period in the life of the Global Fund and we are indeed fortunate to have Professor Kazatchkine lead the secretariat at the start of the fund’s second five-year cycle. He has a right blend of skills and experience needed to manage this unique financial institution” (Global Fund release, 2/8).

Global Fund Should Manage Administrative Expenses, Prioritize Governance, Editorial Says
“Almost nobody … said a bad word about” the Global Fund “until this week” when the Boston Globe reported on an internal inspector general investigation into the business expense practices of the Global Fund’s executive director, a Los Angeles Times editorial says. According to the Times, the Global Fund’s new executive director will “start the job under a cloud of suspicion.” That is a “pity because the allegations, at least so far, don’t seem all that serious,” the editorial adds. “Given the size of its operations,” the Global Fund’s “administrative expenses are relatively modest,” the editorial says, concluding that the Global Fund board should “get a handle on this controversy by making governance matters a priority. The Global Fund lives or dies on its reputation — and so do the millions of people in Africa and across the developing world who need its services” (Los Angeles Times, 2/8).

“Reprinted with permission from kaisernetwork. You can view the entire Kaiser Daily Health Policy Report, search the archives, or sign up for email delivery at kaisernetwork/dailyreports/healthpolicy. The Kaiser Daily Health Policy Report is published for kaisernetwork, a free service of The Henry J. Kaiser Family Foundation . © 2005 Advisory Board Company and Kaiser Family Foundation. All rights reserved.

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HIVMA Calls On President-Elect Obama For Leadership, Realistic Funding For HIV/AIDS – World AIDS Day: Dec. 1, 2008

Statement of HIV Medicine Association (HIVMA) Chair Arlene Bardeguez, MD, MPH:

The majority of the one million-plus people in this country living with HIV are uninsured or rely on public programs for care. As the economy worsens, and the number of people diagnosed rises, the strain on publicly funded programs will only grow. In fact, one in five people with HIV do not yet know they are infected. Most won’t be diagnosed until the disease has progressed to full-blown AIDS.

As part of the coalition AIDS in America, we join with other HIV/AIDS organizations in calling for important changes in prevention, access to care, civil rights, and research within the first 100 days of the new administration. We need an increased federal investment in domestic HIV/AIDS programs, including research and prevention efforts at the Centers for Disease Control and Prevention and the National Institutes of Health, and care and services for those with HIV/AIDS through the Ryan White CARE Act. We also urge President-elect Obama to quickly begin working on a national HIV/AIDS strategy that finally deals realistically with the growing epidemic in the United States.

HIVMA and AIDS in America have high hopes that the new administration can provide renewed leadership and help build on the many positive things that occurred this year, which attest that together we can make a difference. Among the HIV-related triumphs this year are:

the finding that people with HIV who are on treatment have similar survival rates as those of non infected people;

the reality that newly approved treatment options allow for simpler regimens with a better safety profile; and

the fact that states are making progress in implementing routine HIV testing in health care settings.

Our nation has made a critical and unprecedented commitment to the HIV/AIDS crisis in the developing world. That investment must continue, but the crisis at home requires more attention. To that aim the community, health care providers, researchers and government officials at all levels must work collaboratively to bring changes in diagnosis, access to care and treatment, and a decrease in the number of new infections. We are hopeful that with the next Administration’s leadership and a bold new national strategy we can do just that.

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HIVMA is the professional home for more than 3,600 physicians, scientists, and other health care professionals dedicated to the field of HIV/AIDS. Nested within the Infectious Diseases Society of America (IDSA), HIVMA promotes quality in HIV care and advocates policies that ensure a comprehensive and humane response to the AIDS pandemic informed by science and social justice. HIVMA is part of the umbrella group AIDS in America, whose funding recommendations and proposals for the new president’s first 100 days are available online at hivma.

Because of our commitment to global public health issues, HIVMA and IDSA have created the Infectious Diseases Center for Global Health Policy and Advocacy to support and promote U.S. efforts to combat HIV/AIDS and tuberculosis throughout the developing world. More information about the Center is available online.

Source: Steve Baragona

Infectious Diseases Society of America

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Conference On Nanomedicine, Geriatric Care, Brain Injury: Nobel Laureate Keynote Speaker

Sir Harold Kroto, Nobel Laureate, will be the keynote speaker at the Edward Via Virginia College of Osteopathic Medicine Third Annual Via Research Recognition Day and Geriatric Update for Continued Medical Education on Oct. 5-6, 2006.

Kroto, a professor in the School of Chemistry and Molecular Sciences at the University of Sussex, will speak on “Architecture in NanoSpace.” He received the Nobel in Chemistry in 1996 along with Robert F. Curl and Richard E. Smalley for the 1985 discovery of fullerenes (C60 Buckminsterfullerene), a new form of carbon in which the atoms are arranged in closed shells. Kroto’s research areas in addition to fullerenes are spectroscopy of unstable species and reaction intermediates, cluster science, including carbon and metal clusters, microparticles, and nanofibers, and astrophysics, specifically interstellar molecules and circumstellar dust.

The focus on Thursday, Oct. 5, will be nanomedicine and biomedical applications of nanoparticles. Virginia Tech President Charles Steger will provide an introduction to biomedical research at Virginia Tech, where many of VCOM’s faculty members are adjunct faculty.

Other speakers on nanomedicine will be Roop Mahajan, director of the Institute for Critical Technology and Applied Science at Virginia Tech, on “Nanotechnology and Modern Medical Science: Challenges and Opportunities”; Harry C. Dorn, professor of chemistry at Virginia Tech, on “New Nanoscale Multi-Modal Diagnostic and Therapeutic Approaches in Biomedicine”; and Ishwar Puri, professor and head of engineering science and mechanics at Virginia Tech, speaking about “Biomedical Applications of Superparamagnetic Nanoparticles in Microfluidic Systems.”

Mahajan comes to Virginia Tech from the University of Colorado at Boulder and is the founder and co-director of MicroElectronic Devices in Cardiovascular Applications (MEDICA).

Dorn has invented a new family of filled fullerenes with many applications, including as a diagnostic and therapeutic agent that boosts the sensitivity of MRI techniques and improves the diagnosis and treatment of brain tumors. Based on findings with animal models, Dorn and colleagues at Virginia Commonwealth University and Virginia Tech have funding from the National Institutes of Health’s National Cancer Institute to further develop, produce, and test nanoparticles that can identify brain tumor cells and selectively target them for radiation therapy.

On Friday, Oct. 6, topics will be anti-aging medicine, geriatric care, and osteopathic medicine in the genomic era, image-guided therapy, and depression in older adults.

Traumatic Brain Injury will be addressed both days by such speakers as Ross D. Zafonte, DO, professor and chair of the Department of Physical Medicine and Rehabilitation at the University of Pittsburgh Medical School, speaking on clinical trials in traumatic brain injury; Katherine H. Taber of the Veterans Affairs Mid-Atlantic Mental Illness Research, Education, and Clinical Center in Salisbury, N.C., on the neurobiology of traumatic brain injury; and Robin A. Hurley, MD, of the Hefner Veteran Affairs Medical Center in Salisbury, on the neuropsychiatry of traumatic brain injury.

Attendance at the conference is limited to approximately 600 participants. Registration is free for those who apply before Sept. 11, 2006. Registration includes admission to all sessions, continental breakfast, beverages, and lunch. To register, contact Kelly Varelos at kvarelosvcom.vt.edu. On-site registration will be $50 per person and depends on availability of space.

The meeting site will be the Edward Via Virginia College of Osteopathic Medicine (VCOM), 2265 Kraft Drive, Blacksburg, VA. For additional information about the conference, contact Hara Misra at misravt.edu.

* Continued Medical Education (CME) Credits – DO’s: VCOM is accredited by the American Osteopathic Association (AOA). The college anticipates being approved for 12 AOA Category 1-A credits pending approval by the AOA CCME. Each physician should claim only the hours of credit that he/she actually spent in the educational activity.

CME Credits – MD’s: This activity has been planned and implemented in accordance with the Essentials and Standards of the Medical Society of Virginia through joint sponsorship of Lewis Gale CME Organization, the Montgomery Regional Hospital, and the Edward Via Virginia College of Osteopathic Medicine. It is anticipated that the Lewis Gale CME Organization will designate this educational activity for a maximum of 12 credits AMA PRA Category 1 Credit(s)TM. Physicians should only claim credit commensurate with the extent of their participation in this activity.

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VCOM’s research facility is located in the Virginia Tech Corporate Research Center in Blacksburg, Virginia. Learn more about the Edward Via Virginia College of Osteopathic Medicine at vcom.vt.edu/
The Edward Via Virginia College of Osteopathic Medicine is a professional graduate college offering the degree of Doctor of Osteopathic Medicine (D.O.) The college operates with a collaborative agreement with Virginia Tech for research and for student activities.

Contact: Hara Misra

Virginia Tech

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Scientists Discover Crucial Trigger For Tumour Protein

Scientists have discovered an essential protein that controls inflammation induced by ‘tumour necrosis factor’ (TNF) – an important part of the body’s defences against infection and a driver of cancer-associated inflammation, according to research published in Nature.

The study – led by Cancer Research UK-funded scientists based at Imperial College London in close collaboration with scientists at La Trobe University in Melbourne* – may also shed light on the causes of certain autoimmune diseases, such as rheumatoid arthritis and psoriasis.

TNF plays a pivotal role in protecting the body against infection by bacteria, viruses and other pathogens. It does this by directing the immune system to spot rogue pathogens and then destroy them.

As the name suggests, when TNF was first discovered scientists thought its main role in the body was to help kill cancer cells. But later research showed that in many types of cancer TNF instead serves to promote cancer growth.

So rather than destroying cancer cells, it encourages them to grow and spread by triggering inflammation in the surrounding tissues.

Short-term inflammation is used by the body to increase blood flow to an injury or infection, helping it heal faster. But scientists believe prolonged inflammation may be exploited by some cancers to help fuel the growth and spread of the disease.

The researchers discovered how a protein called ‘Sharpin’ prevents TNF from inducing inflammation, providing potential new insights into the link between inflammation and cancer.

Study leader Professor Henning Walczak, based at Imperial College London, said: “Together with our collaborators at La Trobe University in Melbourne, we discovered that the inflammatory skin problems triggered in mice lacking Sharpin could be completely resolved by switching off TNF. This was a striking result, not least because TNF-controlled inflammation is central to a wide variety of different diseases from autoimmune diseases – like rheumatoid arthritis and psoriasis – to cancer.

“Understanding how inflammation is controlled in the body on a molecular level could one day open the door to completely new approaches for treating both cancer and autoimmune disease.”

Dr Lesley Walker, director of cancer information at Cancer Research UK, said: “This important discovery is the culmination of six years work and demonstrates how basic research into the fundamental mechanisms of inflammation may lead to exciting new insights into its links with cancer. Although still at an early stage, we hope this will open up new avenues of research for developing treatments that target cancer-related inflammation in the future.”

References

Gerlach B. et al, Linear ubiquitination prevents inflammation and regulates immune signalling (2011), Nature, DOI: 10.1038/nature09816.

Notes

* Additional collaborators were from the University of Melbourne, German Cancer Research Centre (DKFZ) in Heidelberg and the Mediterranean Institute of Oncology in Viagrande, Italy. Research in the Walczak lab is supported by grants from Cancer Research UK, AICR, BBSRC, Ovarian Cancer Action and the EU Marie Cure Research Training Network ApopTRAIN.

Source:

Cancer Research UK

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Insight Into HIV Immunity May Lead To Vaccine

Latest insights into immunity to HIV could help to develop a vaccine to build antibodies’ defences against the disease, a University of Melbourne study has found.

By investigating the action of the human antibodies called ADCC, in people with HIV, researchers were able to identify that the virus evolves to evade or ‘escape’ the antibodies.

Professor Stephen Kent of the University of Melbourne and one of the senior authors on the paper said ADCC antibodies have been strongly implicated in protection from HIV in several vaccine trials but their action was poorly understood.

“These results show what a slippery customer the HIV virus is, but also shows that these ADCC antibodies are really forcing the virus into changing, in ways that cause it to be weaker,” he said.

“It also implies that if good ADCC antibodies were available prior to infection, via a vaccine, we might be able to stop the virus taking hold. This is the holy grail.”

The group at the University of Melbourne’s Department of Microbiology and Immunology analysed blood samples of people with HIV and found their virus had evolved to evade or ‘escape’ the ADCC antibodies against HIV they are making to try to control their virus.

The team led by Dr Ivan Stratov and Professor Kent employed a novel technology developed in their laboratory to find where ADCC antibodies were attacking the virus. They then looked at how the sequence of the virus had mutated over time to avoid the immune response.

“There is an urgent need to identify effective immunity to HIV and our studies suggest ADCC responses supply significant immune pressure on the virus,” Dr Ivan Stratov, a clinician and researcher said.

The group is now working on designing HIV vaccines to induce ADCC antibodies that make it more difficult for the virus to escape.

The work was published in the prestigious international journal PNAS.

Source:
Rebecca Scott

University of Melbourne

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International Travel Increasing Spread Of New Drug-Resistant Bacteria: Is This The End Of Antibiotics?

A new gene (New Delhi metallo-beta-lactamase [NDM] 1) that enables bacteria to be highly resistant to almost all antibiotics is widespread in Enterobacteriaceae* taken from patients in India and Pakistan, and has also been found in UK patients who travelled to India for elective surgery, according to an Article published Online First and in the September edition of The Lancet Infectious Diseases. The rapid emergence of these multi-drug resistant NDM-1 producing bacteria and their potential worldwide spread could herald a period in which antibiotics become redundant and demands very close international monitoring and surveillance.

In 2009, Timothy Walsh from Cardiff University in the UK and international colleagues first identified the NDM-1 gene in Klebsiella pneumonia and Escherichia coli bacteria taken from a Swedish patient admitted to hospital in India. Worryingly, NDM-1-producing bacteria are resistant to many antibiotics including carbapenems, a group of antibiotics generally reserved for use in emergencies and the treatment of infections caused by multi-resistant bacteria.

In this study, the authors investigated how common the NDM-1 producing antibiotic resistant bacteria are in Bangladesh, India, and Pakistan and the importation of these bacteria into the UK via patients returning from these countries.

The researchers collected bacteria samples from patients presenting with various hospital and community-associated infections in Chennai and Haryana in India, and from patients referred to the UK’s national reference laboratory between 2007 and 2009. Samples were tested for antibiotic susceptibility and the presence of the NDM-1 gene using polymerase chain reaction (PCR) and sequencing.

They identified 44 (1.5%) NDM-1-positive bacteria in Chennai, 26 (8%) in Haryana, 37 in the UK, and 73 in other sites in Bangladesh, India, and Pakistan. NDM-1 was mostly found in E coli (36), the most common cause of community-associated urinary tract infections, and K pneumoniae (111). The NDM-1-producing bacteria were highly resistant to all antibiotics except tigecycline and colistin. In some cases, isolates were resistant to all antibiotics.

Importantly, the NDM-1 gene was found to be present on plasmids, DNA structures that can be easily copied and transferred between different bacteria, suggesting: “an alarming potential to spread and diversify among bacterial populations”.

The authors say that the emergence of NDM-1 positive bacteria is potentially a serious global public health problem as there are few new anti-Gram-negative antibiotics in development and none that are effective against NDM-1. Consequently, we are facing a period in which antibiotics become redundant. They go on: “Even more disturbing is that most of the India isolates from Chennai and Haryana were from community-acquired infections, suggesting that NDM-1 is widespread in the environment.”

They conclude by pointing out that several of the UK NDM-1 positive patients had travelled to India or Pakistan for surgical procedures (including cosmetic) within the past year: “India also provides cosmetic surgery for other Europeans and Americans, and it is likely NDM-1 will spread worldwide.”

In a Comment, Johann Pitout from the University of Calgary in Canada warns that patients who have medical procedures in India should be screened for multiresistant bacteria before they receive care in their home country: “If this emerging public health threat is ignored, sooner or later the medical community could be confronted with carbapenem-resistant Enterobacteriaceae that cause common infections, resulting in treatment failures with substantial increases in health-care costs.”

“Emergence of a new antibiotic resistance mechanism in India, Pakistan, and the UK: a molecular, biological, and epidemiological study”
Karthikeyan K Kumarasamy, Mark A Toleman, Timothy R Walsh, Jay Bagaria, Fafhana Butt, Ravikumar Balakrishnan, Uma Chaudhary, Michel Doumith, Christian G Giske, Seema Irfan, Padma Krishnan, Anil V Kumar, Sunil Maharjan, Shazad Mushtaq, Tabassum Noorie, David L Paterson, Andrew Pearson, Claire Perry, Rachel Pike, Bhargavi Rao, Ujjwayini Ray, Jayanta B Sarma, Madhu Sharma, Elizabeth Sheridan, Mandayam A Thirunarayan, Jane Turton, Supriya Upadhyay, Marina Warner, William Welfare, David M Livermore, Neil Woodford
The Lancet Infectious Diseases August 11, 2010. DOI:10.1016/S1473-3099(10)70143-2

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EnWave Announces Successful Test Results For Antibodies Using FreezeREV Dehydration Technology

EnWave Corporation (TSX VENTURE:ENW) (“EnWave” or “the Company”) today announced that it has successfully dried three different antibodies in the Company’s prototype freezeREV vial dehydration technology. Results from this study showed no detectable visual difference between freezeREV-dried and freeze dried samples when examined with the SDS-PAGE electrophoresis method. Additionally, the indication of the molecular weight was similar between the two dried samples and liquid antibodies. Freeze drying, or lyophilization, is the current industry standard for dehydrating live or active organisms such as antibodies.

Freeze drying can be particularly harsh on sensitive materials such as antibodies because of the length of time the organisms are exposed to extremely low temperatures. The freezeREV prototype has been designed to significantly reduce the drying time and temperature exposure from days, to minutes or hours, creating the potential for a high-speed, cost effective dehydration technology. The Company believes that a commercial-scale freezeREV machine could reduce the costs of dehydration for live or active pharmaceuticals and reagents by as much as 80%.

“These are exciting results for the Company as we are seeing the potential of this technology in a new area of biopharmaceuticals and biomaterials,” said Dr. Durance. “We have tested a variety of proteins in the past, but antibody dehydration could open up a huge new market for EnWave, and this would compliment our existing research into vaccine dehydration.”

Antibodies are infection fighting proteins used in a wide variety of applications including medical research and diagnostics, prenatal therapy, and treatment of diseases such as cancer, heart disease, rheumatoid arthritis and multiple sclerosis. The three polyclonal antibodies used in this study were derived from chicken, rabbit and bovine blood serum, and are used by the pharmaceutical industry for drug research. They are also used in the production of animal vaccines, and as feed additives to improve animal health. Dehydration of antibodies is important to the pharmaceutical and biotechnology sectors, primarily because the process increases the shelf-life of these expensive and difficult-to-manufacture organisms.

freezeREV is a method for drying biomaterials in vials where low moisture levels in the final product are imperative for long product shelf-life. This technology is being designed to create room temperature stable pharmaceuticals or reagents containing live organisms such as viruses, bacteria and antibodies where an emphasis must be placed on maintaining the maximum possible survival rates of these organisms until they are delivered to a patient.

EnWave has initiated a search for a major industry partner with whom to expand testing for both polyclonal and monoclonal antibody products with the goal of proving that freezeREV dehydration technology can be developed into a commercially viable method.

Source
EnWave

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Victorian HIV Test To Help Monitor Sufferers

People living with HIV will benefit from a new test developed by Victoria, Australia scientists that offers a simpler and cheaper way of monitoring the disease in sufferers, Victorian Innovation Minister Gavin Jennings said today.

The test, developed by researchers at the Melbourne-based Macfarlane Burnet Institute, provides a simple way for clinicians to monitor the key CD4 T-cells in people with HIV.

These cells are used as an accurate marker of the disease’s progression because HIV targets these cells, reducing their levels and weakening the immune system which can result in the onset of AIDS.

“The Victorian Government is taking action to promote health and lifestyle benefits through biotech initiatives, such as this new HIV test, which will also create jobs for Victorians,” Mr. Jennings said.

“This test is good news for the 40 million people worldwide diagnosed with HIV – a virus that continues to grow by three million new cases each year. The current monitoring approach using flow cytometry is expensive, complex and only available in major laboratories.

The ELISA (enzyme-linked immunosorbent assay) test addresses an unmet need for a lower-cost, simpler and higher throughput technology suitable for routine use in pathology laboratories.”

The researchers behind the ELISA-based test, led by Associate Professor David Anderson and Professor Suzanne Crowe, have formed a spinout company, SeeD4, and have received funding of $377,000 from the Medical Research Commercialisation Fund (MRCF), a $30 million fund supported by the Victorian Government, for ongoing development.

Mr. Jennings announced the innovation at the international BIO2009 conference in Atlanta, USA, ahead of a keynote address on HIV/AIDS initiatives by Sir Elton John.

“The management of HIV and the use of antiviral therapies require the regular monitoring of circulating CD4 T-cells in patients, that’s why this test is so important,” Mr. Jennings said.

“The measurement of CD4 T-cell levels is initially used to determine when patients should commence treatment. Once on treatment, CD4 T-cells are regularly monitored to ensure that the viral load is effectively managed and that the virus has not become resistant to therapy.”

The MRCF investment will enable completion of the testing and clinical evaluation, including a head-to-head comparison with the flow cytometry method.

The technology was developed to an initial validation stage with funding provided by the Doris Duke Charitable Foundation and the National Health and Medical Research Council.

Source
Victoria

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Scientists Discover Reservoir Where HIV-Infected Cells Can Lay-In-Wait

University of Michigan scientists have identified a new reservoir for hidden HIV-infected cells that can serve as a factory for new infections. The findings, which appear online March 7 in Nature Medicine, indicate a new target for curing the disease so those infected with the virus may someday no longer rely on AIDS drugs for a lifetime.

“Antiviral drugs have been effective at keeping the virus at bay. However once the drug therapy is stopped, the virus comes back,” says senior author of the study Kathleen L. Collins, M.D., Ph.D., associate professor of both internal medicine and microbiology and immunology at the U-M Medical School.

In people infected with HIV (human immunodeficiency virus), the virus that causes AIDS, there’s an unsolved problem with current anti-viral drugs. Though life-saving, they cannot root the virus out of the body. Infected cells are able to live on, undetected by the immune system, and provide the machinery for the virus to reproduce and spread.

Important new research by U-M has discovered that bone marrow, previously thought to be resistant to the virus, can contain latent forms of the infection.

“This finding is important because it helps explain why it’s hard to cure the disease,” Collins says. “Ultimately to cure this disease, we’re going to have to develop specific strategies aimed at targeting these latently infected cells.”

“Currently people have to take anti-viral drugs for their entire life to control the infection,” she says. “It would be easier to treat this disease in countries that don’t have the same resources as we do with a course of therapy for a few months, or even years. But based on what we know now people have to stay on drugs for their entire life.”

Using tissue samples, U-M researchers detected HIV genomes in bone marrow isolated from people effectively treated with antiviral drugs for more than six months.

While further studies are needed to demonstrate that stem cells can harbor the HIV virus, the study results confirm that HIV targets some long-lived progenitor cells, young cells that have not fully developed but mature into cells with special immune functions. When active infection occurs the toxic effects of the virus kill the cell even as the newly made viral particles spread the infection to new target cells.

“Our finding that HIV infects these cells has clear ramifications for HIV disease because some of these cells may be long-lived and could carry latent HIV for extended periods of time,” she says. “These HIV cell reservoirs can be induced to generate new infections.”

The new research gives a broader view of how HIV overwhelms the body’s immune system and devastates its ability to regenerate itself.

Globally more than 30 million people are infected with HIV, including millions of children. Improvements have been made since the 1990s in the way the disease is treated that has led to an 85 percent to 90 percent reduction in mortality.

“Drugs now available are effective at treating the virus, making HIV more of a chronic disease than a death sentence,” Collins says. “This has made a huge impact in quality of life, however only 40 percent of people worldwide are receiving anti-viral drugs and unfortunately that means that not everybody is benefiting.”

Additional authors: Christoph C. Carter, Adewunmi Onafuwa-Nuga, Lucy A. McNamara, James Riddell IV, and Dale Bixby, all of U-M; and Michael R. Savona, University of Texas Health Science Center, San Antonio, Texas, formerly of U-M Heath System.

Funding: National Institutes of Health. The work of first author Carter was supported by the Wellcome Foundation, U-M Molecular Mechanisms in Microbial Pathogenesis Training Grant and a Rackham Predoctoral Fellowship, and McNamara’s work was supported by a National Science Foundation Predoctoral Fellowship and a Bernard Maas Fellowship.

Reference: 10.1038/nm.2109

Source
University of Michigan Health System

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