Xenotropic murine leukemia virus¨Crelated virus (XMRV) has been the subject of many studies since its discovery in 2006, but conflicting reports have created an unclear picture of XMRV¡¯s role in human disease.
In three recent studies published in the November 15 issue of The Journal of Infectious Diseases, now available online, the evidence supports a possible link between XMRV and prostate cancer but not other links involving chronic fatigue syndrome, HIV infection, or hepatitis C virus (HCV) infection. (Please see below for links to these articles online.)
In one of the studies, led by Athe Tsibris, MD, investigators from Boston determined XMRV prevalence in a variety of North American clinic populations. The study included healthy subjects, participants with CFS, and participants with chronic immune activation or suppression.
Study samples were obtained from adult patients presenting to outpatient clinics or from pre-existing samples at Brigham and Women¡¯s Hospital, Massachusetts General Hospital, and Dana-Farber Cancer Institute. Researchers did not detect XMRV in any of the 293 patients tested, and the investigators did not find an association between XMRV and patients with CFS, chronic immune suppression, or medical conditions associated with chronic immune activation.
Researchers were surprised that they did not detect XMRV in any of the study participants, despite the high prevalence previously reported. A previous study in the United States found evidence of XMRV DNA in 67 percent of subjects with chronic fatigue syndrome (CFS), compared to 3.7 percent of healthy controls. Subsequent studies in Europe, however, were unable to demonstrate the presence of XMRV in CFS subjects or healthy controls.
¡°The findings suggest that in the population we tested, XMRV is not associated with chronic fatigue syndrome and suggests that differences in PCR technique from study to study do not explain the disparate results seen in XMRV studies of chronic fatigue syndrome,¡± Dr. Tsibris said.
A second study, led by Eleanor Barnes, MD, aimed to detect XMRV in patients with HIV-1 or hepatitis C virus (HCV) infection in the United Kingdom and Switzerland. Because the route of transmission for XMRV has not been established, Dr. Barnes and the researchers tested individuals who were at high risk for contracting blood-borne or sexually transmitted infections. Investigators tested plasma and peripheral blood mononuclear cells to determine if these patients were at risk for XMRV infection.
Investigators did not find XMRV in any of the 230 patients with HIV or HCV infections. According to the researchers, ¡°This study provides the first evidence that if XMRV is a human pathogen, it is not enriched in the blood of patients with HIV or HCV, and by implication it is unlikely to be spread though sexual or blood-borne routes in the UK and Western Europe.¡± In light of these findings, Dr. Barnes noted that further studies are necessary to explore potential transmission routes and determine which members of the population may be at risk.
The possible association between XMRV and human prostate cancer has also been questioned by conflicting studies. Jason T. Kimata, PhD, and investigators from the Baylor College of Medicine looked for XMRV in 144 patients with prostate cancer from the southern United States. Researchers were able to detect XMRV in 22 percent of men with prostate cancer. XMRV was present in both normal and tumor tissue of men with prostate cancer. According to the authors, this suggests that the virus may not specifically target cancer cells for infection and that infection may precede cancer. Dr. Kimata emphasized the need to ¡°continue discussions about XMRV detection assay methodologies, so that discrepancies in the findings of different research groups can be addressed.¡±
In an accompanying editorial, Frank Maldarelli, MD, PhD, and Mary Kearney, PhD, of the National Cancer Institute, pointed out that differences among various studies may be related to a variety of factors, including geography, patient selection, and detection techniques. They noted that these three new studies highlight the need for standardization of detection assays, prospective epidemiological surveys, and sharing of reagents and samples among investigators. Only when this is done in a rigorous fashion will it become clear what role XMRV or related viruses have in human disease.
Investigators from Boston did not find an association between XMRV and patients with CFS, chronic immune suppression, or medical conditions associated with chronic immune activation, in a study in the November 15 issue of The Journal of Infectious Diseases.
In a second study in the same issue, European researchers did not find XMRV in any of 230 patients infected with HIV or HCV, suggesting that XMRV is unlikely to be transmitted by blood or sexual exposure.
Researchers at Baylor College of Medicine detected XMRV in 22 percent of men with prostate cancer, in both tumor and normal tissues, according to a third study in the issue.
The studies highlight the need for standardization of XMRV detection assays, prospective epidemiologic surveys of its prevalence, and sharing of reagents and samples among investigators to clarify what role XMRV or related viruses play in human disease.
Note: The three studies and the accompanying editorial are available online:
¡°Xenotropic Murine Leukemia Virus¨CRelated Virus Prevalence in Patients with Chronic Fatigue Syndrome or Chronic Immunomodulatory Conditions¡± http://www.journals.uchicago.edu/doi/abs/10.1086/657168¡°Failure to Detect Xenotropic Murine Leukemia Virus¨CRelated Virus in Blood of Individuals at High Risk of Blood©Borne Viral Infections¡±
http://www.journals.uchicago.edu/doi/abs/10.1086/657167¡°Detection of Xenotropic Murine Leukemia Virus¨CRelated Virus in Normal and Tumor Tissue of Patients from the Southern United States with Prostate Cancer Is Dependent on Specific Polymerase Chain Reaction Conditions¡±
http://www.journals.uchicago.edu/doi/abs/10.1086/656146¡°Current Status of Xenotropic Murine Leukemia Virus¨CRelated Retrovirus in Chronic Fatigue Syndrome and Prostate Cancer: Reach for a Scorecard, Not a Prescription Pad¡±
Founded in 1904, The Journal of Infectious Diseases is the premier publication in the Western Hemisphere for original research on the pathogenesis, diagnosis, and treatment of infectious diseases; on the microbes that cause them; and on disorders of host immune mechanisms. Articles in JID include research results from microbiology, immunology, epidemiology, and related disciplines. It is published under the auspices of the Infectious Diseases Society of America (IDSA). Based in Arlington, Va., IDSA is a professional society representing nearly 8,000 physicians and scientists who specialize in infectious diseases. Nested within the IDSA, the HIV Medicine Association (HIVMA) is the professional home for more than 2,600 physicians, scientists and other health care professionals dedicated to the field of HIV/AIDS. 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.
John Heys | EurekAlert!
Further reports about: > CFS > Cancer > Chronic Fatigue Syndrome > Disease > Fatigue > HCV > HIV > HIVMA > Human vaccine > IDSA > Infectious Diseases > Medicine > Syndrome > Virus > Virus¨CRelated > XMRV > Xenotropic > chronic insomnia > hepatitis C virus > immune activation > immune suppression > infectious disease > infectious outbreaks > leukemia > prostate > prostate cancer
Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington
New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
23.06.2017 | Physics and Astronomy
23.06.2017 | Life Sciences
23.06.2017 | Information Technology