GenoMed’s West Nile Virus Trial Endorsed By Emergency Medicine Authority

GenoMed (OTC Pink Sheets GMED), a Next Generation Disease Management company whose business is public health™, today announced the endorsement of its trial for West Nile virus encephalitis by an authority in Emergency Medicine, Dr. Neal Handly.

Dr. Handly is Associate Director of Research for the Department of Emergency Medicine at Drexel University College of Medicine and a Fellow of the American Academy of Emergency Medicine. Dr. Handly chairs the Academy’s Subcommittee on Information Technology.

Dr. Handly said, “GenoMed’s protocol is extremely exciting, since we’re in the grip of another West Nile epidemic this summer without any known treatment. The Emergency Room is where these cases are seen first. It makes sense to have the ER be a partner in a clinical trial.”

Dr. Handly continued, “Dr. Moskowitz uses safe medicines already familiar to every ER physician. What makes his approach appealing is the possibility that it may work for many viruses, including avian influenza and bioterrorist viral attacks. These last two scenarios are of special concern to the Emergency Medicine community.”

About Dr. Handly

Dr. Neal Handly is an Assistant Professor in the Department of Emergency Medicine at Drexel University College of Medicine in Philadelphia, PA. He was consulted to create a state-of-the-art ER this summer in Beirut, Lebanon but has been prevented from doing so by the current hostilities.

About GenoMed

Since 2003, GenoMed has been using safe, FDA-approved, prescription-only blood pressure pills to treat West Nile virus encephalitis. So far, GenoMed has had an 86% treatment success rate (19 of 22 patients). This summer the Company extended its trial successfully to include horses. Anyone can download the WNV trial protocol from GenoMed’s website, www.genomed, by clicking on the “West Nile trial” link. An email address is required for clinical follow-up.

Safe Harbor Statement

This press release contains forward looking statements, including those statements pertaining to GenoMed, Inc.’s (the Company’s) treatments. The words or phrases “ought to,” “should,” “could,” “may,” or similar expressions are intended to identify “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Actual results could differ materially from those projected in the forward looking statements as a result of a number of risks and uncertainties, including but not limited to our research and development being subject to scientific, economic, regulatory, governmental, and technological factors. Statements made herein are as of the date of this press release and should not be relied upon as of any subsequent date.

Unless otherwise required by applicable law, we specifically disclaim any obligation to update any forward-looking statements to reflect occurrences, developments, unanticipated events or circumstances after the date of such statement.

genomed Continue reading

Merced Sun-Star Examines HIV/AIDS Epidemic Among Migrants Who Travel Between U.S., Mexico

The Merced Sun on Saturday examined the increasing number of HIV/AIDS cases among Mexicans in the U.S. and Mexico, “a trend that researchers and health officials attribute to migrants’ high-risk behavior and constant movement.” Juan Ruiz, director of the California Office of AIDS, said that the agency did not find any HIV-positive migrant workers when it conducted its first study in 1994. However, up to 1% of the population might be HIV-positive, according to a study of 600 migrant workers conducted in Fresno and San Diego counties by the Universitywide AIDS Research Program of the University of California. Researchers said that migrant workers, who travel to the U.S. in search of a better life for themselves and their families, often come to the country alone, making them more likely to engage in high-risk behaviors. Migrant workers who do not have access to their normal support systems are “more likely to engage in high-risk behavior in order to deal with loneliness and fear,” Ruiz said. Although the number of new HIV cases reported among migrant workers is lower than in other at-risk populations, such as blacks, public health workers need to put into practice HIV/AIDS education and prevention programs, Salvador Sandoval of the Golden Valley Health Center said. Migrant workers in California are eligible for government assistance for treatment and care regardless of their immigration status, according to the Sun-Star. “The thing is, really, now if someone is diagnosed with HIV, we end up paying for it,” Sandoval said, adding, “So it is in our benefit to prevent the disease in everybody” (Fox, Merced Sun-Star, 11/19).

The Merced Sun-Star

“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. Continue reading

Despite Record Number Of HIV Screenings, One Third Of Diagnoses Still Occurring Late

Although record numbers are being tested for HIV in the USA, over 200,000 infected individuals are not aware of their HIV status, and one third of diagnoses are occurring later on during the infection when treatment is less effective. A CDC (Centers for Disease Control and Prevention) MMWR report says increased testing is required, especially among populations where HIV diagnoses occur the most.

HIV (human immunodeficiency virus) has become a major cause of health-care expenditures in the USA, it also burdens the country with considerable morbidity and mortality. For HIV positive individuals to be treated effectively, their infection must be diagnosed early. For diagnosis to occur early on during the disease, HIV testing has to be thorough and nationwide. Early diagnosis also reduces incidences of human-to-human transmission.

Information from the National Health Interview Survey, 2001-2009 was used to work out what proportion of 18 to 64 year-olds got tested for HIV in the USA. National HIV Surveillance System data were gathered to estimate numbers, percentages and HIV/AIDS diagnoses rates, as well as late-HIV infection diagnoses rates. A late diagnosis is one that occurs at least 12 months after infection started.

The researchers found that:

40% of 18 to 64 year olds were at some time tested for HIV from 2001 to 2006. This percentage rose to 45% in 2009.
From 2001 to 2004 about 37% of those diagnosed HIV positive were diagnosed after being infected for at least 12 months (late diagnosis). By 2007 the figure dropped to 32.3%.
Late diagnoses ranged from 25% to 47.2% in 37 states with mature HIV reporting systems in 2007.
51.2% of HIV diagnoses were among African-Americans in 2008.
In 2008, about 55% of transmissions occurred among non-injecting males who claimed to have had male-to-male sexual contact.

South and Northeast census regions, as well as the states with the largest populations had the highest AIDS diagnosis rates.

The CDC says that health care providers should widen routine screening to include ALL adults. Population groups with higher HIV incidence, as well as geographical areas where HIV prevalence is higher should be tested more often.

Individuals at high risk, such as gay, bisexual, and other males who have sex with males should undergo testing at least once a year.

Public health authorities should inform their populations about the importance of HIV testing.

The CDC informs that 56,000 new infections are reported in the USA each year, approximately one new one every 9.5 minutes. If left untreated, an HIV positive individual will eventually develop AIDS (acquired immunodeficiency syndrome); usually within ten years. Treatment (antiretroviral therapy) will delay the progression of the disease and the patient will live much longer. However, treatment is much more effective if it starts soon after HIV infection, when no symptoms are present.

An HIV-positive 25-year-old patient who receives good treatment early on will typically live 39 years longer than an HIV-positive patient of the same age who doesn’t get treated properly and promptly.

1.1 million adults and adolescents were thought to be HIV positive in the USA in 2006. Approximately 21% of them did not know about their HIV status.

“Vital Signs: HIV Testing and Diagnosis Among Adults – United States, 2001–2009″
Morbidity and Mortality Weekly Report (MMWR) – CDC

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They Are Young And Need The Job: A Second Chance For Dangerous T-cells

The immune system’s T-cells react to foreign protein fragments and therefore are crucial to combating viruses and bacteria. Errant cells that attack the body’s own material are in most cases driven to cell death. Some of these autoreactive T-cells, however, undergo a kind of reeducation to become “regulatory T-cells” that keep other autoreactive T-cells under control. A group led by immunologist Professor Ludger Klein of LMU Munich has now shown that the developmental stage of an autoreactive T-cell is decisive to its ultimate destiny. Young autoreactive T cells are very readily reeducated into regulatory T-cells. Under identical conditions, however, older T cells become fully activated and can cause damage they are in a way resistant to reeducation. “We now intend to study at the molecular level what makes a T-cell accessible for reeducation,” said Klein, “because then it may be possible to convert even normal adult T-cells, which can be obtained easily and in great numbers from blood. Possibly, they could then be used as regulatory T-cells in therapies for autoimmune diseases such as type-1 diabetes or multiple sclerosis: these are diseases that are triggered by uncontrolled autoreactive T-cells.” (PNAS, 10 June 2009)

During their development in the thymus gland, a kind of ‘T-cell school’, every T-cell is fitted out with its own personal receptor. The diversity of these receptors allows the immune system to respond to nearly all pathogens. Since T-cell receptors are all randomly constructed, there is also a constant production of T-cells in the thymus that may recognize and attack the body’s own structures. “Most of these dangerous autoreactive T-cells, though, are sorted out in a screening process before they leave the thymus,” Klein reported. “This negative selection, that is the elimination of autoreactive T-cells that would otherwise attack their own organism, is an important requirement for immune tolerance.”

But not all autoreactive T-cells are driven to cell death. Some of them are ‘reeducated’ into so-called regulatory T-cells. While these still possess a T-cell receptor that targets the body’s own structures, they have been reprogrammed during their development in the thymus so that they can no longer cause any damage. In fact, it is “quite the opposite,” as Klein explained. “They even keep other nearby errant T -cells under control. This is why the mechanisms for the creation of regulatory T-cells are of enormous practical interest. Deciphering these processes could lead to new therapeutic approaches for autoimmune diseases such as multiple sclerosis, rheumatic arthritis and type-1 diabetes, which are triggered by autoreactive T-cells.”

Klein and his colleagues are working on a study into unexplained aspects of regulatory T-cells: How can negative selection, i.e. induced cell death, and reprogramming into regulatory T-cells both take place in the thymus gland, right alongside each other? Why does apparently the same trigger drive some cells to ‘suicide’ while bringing on a ‘reeducation process’ in others? “One largely popular hypothesis among immunologists in answer to these questions is based on the fact that T-cells can only recognize their target structures if they have them presented to them by other immune cells,” said Klein. “Since there are various subspecies of these antigen-presenting cells in the thymus, we tested whether some of them are possibly specialized in controlling one or the other T-cell destinies with a negative result.”

Instead, it turned out that the developmental stage the ‘age’ as it were of the T-cells is crucial. This was even observable in vitro: Young T cells are very readily reeducated into regulatory T-cells, while older T-cells are largely ‘resistant to reeducation’ under identical conditions. “It is important for us to understand this ‘educability’ at a molecular level,” Klein said, “because then we might be able to manipulate adult, non-autoreactive T cells to our needs, since they can be obtained in the millions from the blood of patients. Young T cells, on the other hand, only exist in the thymus. We will now investigate whether there is a specific time window in the life of a young T-cell that allows negative selection or reprogramming into regulatory T-cells. We are also trying to decode the molecular switch inside T-cells that controls this cell-autonomous switching as a response to external signals.”

Source: LMU Continue reading

HUD Announces $18.8M In Grants To Programs Providing Housing Assistance To HIV-Positive People, Their Families, USA

U.S. Department of Housing and Urban Development Secretary Alphonso Jackson on Wednesday announced $18.8 million in grants for 16 programs operating in 15 states that help cover housing costs for HIV-positive people, the AP/Aberdeen American News reports (AP/Aberdeen American News, 11/30). The funding — which is part of HUD’s Housing Opportunities for Persons With AIDS Program — aims to help 545 families that are either homeless or at “extreme risk” of being dispossessed to find “traditional supportive housing” for the next three years, according to a HUD release. “In keeping with the theme of this year’s World AIDS Day, HUD is ‘keeping the promise’ to work with exceptional local programs that serve the most vulnerable among us,” Jackson said, adding, “These local projects provide real housing solutions for those who might otherwise be calling the streets their home.” According to HUD, the grants also will bring about an additional $23.5 million in funding from other public and private donors for the 16 programs (HUD release, 11/30). HOPWA in 2005 budgeted $282 million to help programs nationwide provide housing for HIV-positive people and their families (AP/Boston Globe, 11/30). Although HOPWA is only a small portion of HUD’s overall budget, “it takes care of those who fall through the cracks,” Sen. Mel Martinez (R-Fla.), a former HUD secretary who appeared with Jackson in Tampa, Fla., to announce the grants, said (Zink, St. Petersburg Times, 12/1).

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“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. Continue reading

HIV patients may be infected with more than one type of HIV

Some HIV patients may be plagued by more than one type of HIV infection according to researchers at the McGill AIDS Centre, Sir Mortimer B. Davis – Jewish General Hospital and the McGill University Health Centre. They have shown that some patients may be susceptible to a second infection with another HIV virus including viruses resistant to drugs. This infection with a second HIV virus is called superinfection.

“This is the first time we have seen a patient infected with two different forms of drug-resistant HIV,” says MUHC clinician Dr. Jean-Pierre Routy, an associate professor of Medicine at McGill University and co-author of the study. “These emerging drug resistant viruses present a treatment challenge and the existing drug cocktails will need to be tailored accordingly.”

“Our findings are different than those previously published, ” says Sir Mortimer B. Davis – Jewish General Hospital clinician Dr. Mark Wainberg, a professor of Medicine at McGill University and senior author of the study. “We originally believed, once an individual was infected with one type of HIV they became immune to another HIV infection. Our findings clearly show that this is not the case and will have widespread implications for HIV management, diagnosis and prognosis.”

This groundbreaking news is in part due to the development of a new technical tool that permits cloning of the virus.

These findings are published in the August issue of AIDS and are currently available online at gateway.ut.ovid/gw1/ovidweb.cgi.

Christine Zeindler
christine.zeindlermuhc.mcgill
514-934-1934 ext. 36419
pager: 514-406-1577
MUHC Communications Services Continue reading

University looks to the past in fight against disease

A review of the history of infectious diseases commissioned by the Government is to be carried out by The University of
Manchester.

The report aims to produce a long-term perspective on the detection and identification of infectious diseases and inform
policy at a national and international level.

The study by the University’s Centre for the History of Science, Technology and Medicine (CHSTM) will reflect on the
experience of dealing with human and animal disease problems to inform future research and management policies.

Professor Michael Worboys, who heads CHSTM, said the Office of Science and Technology (OST) commission was the first of its
kind for British historians of science.

“OST wanted a research centre that could write a review of the experience of the management of infectious diseases in the
20th Century in both industrialised and third world countries.

“Our study will review the evolving risk of diseases, changing requirements for detection and identification, and input
cutting-edge science.”

Dr Abigail Woods, a science historian and qualified vet, will head the project, which is expected to last 3 months and will
focus primarily on HIV/Aids, TB and foot and mouth disease.

She said: “One aspect we will be looking at is the globalisation of the disease environment and what technologies we should
be investing in to tackle future disease outbreaks.

“We will also look at the difficulties of treating disease in the developing world where cultural differences mean
alternative health policies are required.”

The University of Manchester’s Centre for the History of Science, Technology and Medicine is part of the Faculty of Life
Sciences and is the largest centre of its kind in the UK.

The CHSTM report will be published by OST’s Foresight Review, which aims to “provide challenging visions of the future to
ensure effective strategies now”.

OST falls within the Department of Trade and Industry (DTI), headed by the Secretary of State for Trade and Industry, the Rt
Hon Alan Johnson MP.

The study is being sponsored by the Department for the Environment, Food and Rural Affairs (Defra) and the newly formed Arts
and Humanities Research Council.

Contact: Aeron Haworth
aeron.haworthmanchester.ac
44-161-275-8383
University of Manchester
manchester.ac Continue reading

Enzyme reins in runaway inflammation; May prove potent drug target

An enzyme found in nearly all animal and human cells acts as a natural brake to prevent potentially deadly runaway inflammation, UCSF scientists have discovered. The discovery in research with mice suggests a promising target for treating a range of inflammatory diseases in which the body’s immune reaction to bacterial invasion spirals out of control, the researchers report.

The enzyme, known as A20, controls the first step in the series of signals that unleash immune system soldiers against a foreign microbe, the scientists found. The enzyme’s action, they discovered, blocks signals from pivotal receptors on immune cells, known as toll-like receptors (TLRs), that directly sense the presence of dangerous bacteria and other microbes.

The research shows that A20 prevents over-reactions of the immune system to blood infections known as sepsis — a life-threatening condition in which bacteria invade the bloodstream. Unchecked by A20, the new research shows, an over-reactive immune response can lead to a deadly collapse of blood pressure. Because bacteria are plentiful in our intestines, the protein may also control the immune reaction that can cause inflammatory bowel disease, the research shows.

Discovery of the ubiquitous enzyme’s role in shutting down rampant inflammation is being published online August 29 by Nature Immunology.

The research adds to earlier work by the UCSF scientists and colleagues, published in Science, showing that A20 blocks signals triggered by one of the major agents of inflammation — the immune system’s tumor necrosis factor (TNF). In the new study, the scientists found that mice lacking genes for both the A20 enzyme and TNF still exhibited a high level of inflammation, indicating that the anti-inflammation protection afforded by A20 is at least in part independent of TNF.

“Finding one enzyme that can rein in two potent pathways of inflammation increases the potential benefits of developing drugs to enhance or restore A20′ s effectiveness,” said Averil Ma, MD, Rainin Distinguished Professor of Medicine at UCSF and senior author on the Nature Immunology paper.

In addition to restricting inflammation, A20 may also protect tissues from the damage inflammation can cause, Ma said. His group found that A20 protects cells from “programmed cell death,” a process by which cells near the site of inflammation may be killed. Many autoimmune diseases such as type 1 diabetes and arthritis involve cell death and damage to tissues caused by programmed cell death, and A20 may naturally prevent this damage, Ma said.

Finally, mounting evidence has linked subtle and chronic states of inflammation with atherosclerosis, the process by which arteries become clogged and lead to heart attacks and strokes. The A20 enzyme may also be a good target to treat these diseases, Ma said.

“Finding that A20 may control multiple important inflammatory processes provides an extremely attractive model — a lesson from nature — showing how one might use a single protein to have multiple therapeutic benefits,” Ma said. “A drug that mimicked A20′s sundry functions could be extraordinarily useful.”

A20 controls inflammation by blocking the immune system’s first line of defense against bacterial attack. When bacteria invade, their carbohydrates bind to TLRs on the surface of macrophages and other immune cells. This initiates a chain reaction of signals in which proteins inside the macrophages are modified. The end result: the macrophages produce and secrete tumor necrosis factor (TNF), interleukin-1 and other cytokines that induce inflammation.

The researchers showed that A20 shuts down one of these signaling proteins, called TRAF6, turning off the immune system cascade. The enzyme, they found, disables the signaling molecule by cleaving off from it a small protein called ubiquitin which would normally activate the signaling molecule.

Recent studies have suggested that ubiquitin modifications may be very important for regulating a wide variety of inflammatory signals within cells. The new research, along with a study by Ma and colleagues published online July 18 by Nature, shows that A20 modifies ubiquitin-containing proteins in two ways, both to deactivate the proteins and remove them.

Lead author on the Nature Immunology paper is David L. Boone, UCSF assistant adjunct professor of gastroenterology working with Ma’s lab.

Co-authors on the paper and collaborators in the research are Emre Turner, MA; Eric G. Lee, BA; and Regina-Celeste Ahmad, BA; and Paula Hurley, BA, all graduate students in medicine at UCSF; Matthew T. Wheeler, BA, graduate student in medicine at University of Chicago; Colleen Tsui, BA, graduate student in biochemistry and molecular biology, School of Public Health, Johns Hopkins University; Marcia Chien, BA, and Sophia Chai, BA, both senior research technicians in Ma’s lab; and Osamu Hitotsumatsu, MD, postdoctoral fellow in medicine at UCSF; Elizabeth McNally, MD, associate professor of medicine, University of Chicago; and Cecile Pickart, PhD, professor of biochemistry and molecular biology at Johns Hopkins University.

The research was supported by grants from the National Institutes of Health.

Contact: Wallace Ravven
wravvenpubaff.ucsf.edu
415-476-2557
University of California – San Francisco Continue reading

New Study Shows Potential To Treat Or Prevent Viral Cancers

A new study, presented at the SNM 55th Annual Meeting, shows that radioimmunotherapy (RIT) targeting viral antigens offers a novel option to treat – or even prevent – many viral cancers by targeting cancer cells expressing viral antigens or infected cells before they convert into malignancy.

“There is an urgent need to find new approaches to treating and preventing viral cancers,” said Ekaterina (Kate) Dadachova, associate professor of nuclear medicine and microbiology and immunology at Albert Einstein College of Medicine, Bronx, N.Y. and lead researcher of the study, Viral Antigens as Novel Targets for Radioimmunotherapy of Viral Cancers. “The magnitude and global health-burden associated with viral cancers is only now being realized.”

It is estimated that up to 25 percent of all cancers are currently linked to existing viral infections. Most of these cancers are extremely difficult to treat and cannot successfully be reduced or removed using conventional therapies or treatments. Viral cancers include cervical cancers caused by infection with a human papillomavirus (HPV), a sexually transmitted disease; hepatocellular carcinoma (HCC), a cancer of the liver; various lymphomas and carcomas in patients with AIDS/HIV; and other cancers.

According to Dadachova, this is the first time that researchers have attempted to target viral antigens on cancers, although the use of RIT for the treatment of cancer has been under development for thirty years. However, the targets of RIT therapy to date have included only “self” human antigens, which are overexpressed on the tumors but also expressed on normal tissues. Viral antigens, on the contrary, are expressed only on the tumors and nowhere else in the body.

The idea to perform the study was suggested by Dr. Arturo Casadevall, chair of the department of microbiology and immunology at Albert Einstein College of Medicine, who collaborates with Dadachova on developing radioimmunotherapy of infectious diseases and cancers. The study involved treating experimental cervical cancer and hepatocellular carcinoma in nude mice with antibodies to respective viral antigens expressed on these tumors. The antibodies were radiolabeled with 188-Rhenium – a powerful beta-emitting radionuclide. “This study demonstrates a real possibility for more specifically targeted cancer treatments,” said Dadachova. “Targeting those antigens with radiolabeled molecules offers exquisite specificity – and will hopefully allow us to significantly increase the efficacy of treatment by administering more individualized doses while avoiding toxicity.”

“Nuclear medicine and molecular imaging offer the ability to target disease on a truly molecular level that is unmatched by any other imaging or therapeutic modality,” said Dadachova. “Targeting viral antigens with radiolabeled antibodies (or also with specific peptides or aptamers) will allow the extremely precise diagnosis of such cancers and their effective therapy. Furthermore, this approach will make possible ‘molecular prevention’ of viral cancers, when infected cells will be targeted before they become cancerous.”

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Dadachova and her team will also be recognized for this study by SNM’s Young Professionals’ Committee, which recognizes the contributions of significant studies to the fields of nuclear medicine and molecular imaging by young researchers. The Young Professionals’ Committee Award was presented on Sunday, June 15, during a luncheon.

This study was supported by the National Institutes of Health (NIH), Center for AIDS Research (CFAR) and Albert Einstein Cancer Center (AECOM).

Scientific Paper 412: E. Dadachova, X. Wang, E. Revskaya, R.A. Bryan, A. Casadevall, Albert Einstein College of Medicine, Bronx, N.Y., “Viral Antigens as Novel Targets for Radioimmunotherapy of Viral Cancers,” SNM’s 55th Annual Meeting, June 14-18, 2008.

About SNM – Advancing Molecular Imaging and Therapy

SNM is an international scientific and medical organization dedicated to increasing understanding and sound practice of molecular imaging throughout the medical community and with the public. Due to the work of SNM members, molecular imaging is a vital element of today’s medical practice, adding an additional dimension to diagnosis that can change the way common and devastating diseases are understood and treated.

Our more than 16,000 members set the standard for molecular imaging practice by creating procedure guidelines, sharing information through our Journal and meetings, and leading advocacy on key issues that affect imaging research and practice. For more information visit snm/.

Source: Amy Shaw

Society of Nuclear Medicine Continue reading

In Hematopoietic Stem Cells P21 Stops HIV-1 In Its Tracks

Hematopoietic stem cells (HSCs) are one of the few cell types able to resist infection with HIV-1 despite expressing the cell surface molecules to which HIV-1 binds before entering a cell. In a study that appears in the February issue of the Journal of Clinical Investigation, researchers from Harvard Medical School, Boston, show that HSC expression of a protein known as p21Waf1/Cip1/Sdi1 (p21) is required for HSCs to be resistant to infection with HIV-1.

David Scadden and colleagues showed that HSCs in which expression of p21 was decreased were more susceptible to infection with HIV-1 than cells expressing normal levels of p21. Further analysis showed that p21 did not inhibit HIV-1 entering the cells, rather it prevented the viral DNA integrating into the host cell genome by binding to the HIV-1 integrase complex and preventing it from mediating chromosomal integration. This protective mechanism was specific for HIV-1, as decreased expression of p21 in HSCs did not allow a related virus (SIVmac-251) to productively infect the HSCs. This study therefore identifies p21 as a protective factor that prevents HSCs being infected with HIV-1.

In an accompanying commentary, Paul D. Bieniasz from the Aaron Diamond AIDS Research Center, New York, discusses how this study adds p21 to an ever-growing list of cellular proteins that alter the sensitivity of a cell to infection with HV-1, but cautions that “it would seem premature to dub p21 a bona fide restriction factor.” (a protein whose major, and perhaps only, role is to prevent retrovirus replication).

TITLE: Primitive hematopoietic cells resist HIV-1 infection via p21Waf1/Cip1/Sdi1

AUTHOR CONTACT:
David T. Scadden
Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.

Clyde S. Crumpacker
Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.

ACCOMPANYING COMMENTARY

TITLE: An intrinsic host defense against HIV-1 integration?

AUTHOR CONTACT:

Paul D. Bieniasz
Aaron Diamond AIDS Research Center, The Rockefeller University, New York, New York, USA.

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JCI table of contents: Feb. 1, 2007

Contact: Karen Honey

Journal of Clinical Investigation Continue reading