Update on Xenotropic Murine Leukemia Virus-Related Virus (XMRV)
IS CHRONIC FATIGUE MISSED XMRV? ANOTHER RETROVIRUS? TESTING AND TREATMENT DEFECTS? MISSED NEW BABESIA OR BARTONELLA SPECIES? MISSED OTHER VIRUS CLUSTERS, MISSED LYME DISEASE, MISSED INDOOR INFLAMMATORY MOLD OR BACTERIA, OR MISSED MYCOPLASMA OR ???
SOME FEEL AT LEAST PART OF CHRONIC FATIGUE IS DUE TO XMRV: HERE IS A FREE UPDATE
Update on XMRV by Dr. AzRa Mael, MD
What is XMRV (aka Xenotropic Murine Leukemia Virus-Related Virus)? Does it cause Chronic Fatigue Syndrome? What other illnesses might it be associated with? How can it be treated?
XMRV is the current name given to this recently discovered group of retroviruses that infects humans.
It is a member of the third known family of human retroviruses, a Human Gamma Retrovirus (HGRV), and in time these viruses may be renamed HGRV.
Human Immunodeficiency Virus (HIV) and Human T-Lymphotropic Virus (HTLV) are the other 2 families of human retroviruses that may be more familiar to some.
XMRV was first discovered in association with prostate cancer in 1996. Only recently (2009) was the virus found to be strongly associated with Chronic Fatigue Syndrome by a group of collaborating labs, including Dr. Mikovits's lab at the Whittemore Peterson Institute (WPI).
The presence of other closely related viruses (murine leukemia virus related-viruses or MLV-related viruses) was then independently and robustly confirmed by the Harvard / NIH / FDA collaborative effort headed by Dr.'s Lo and Alter in 2010.
The family of viruses consists of multiple closely related viral mutations, which is typical of retroviruses. In studies, approximately 80-90% (perhaps more) of people with CFS have XMRV and closely related viruses, compared to 4-7% of controls.
The strength of this association has led to the hypothesis that XMRV causes CFS.
However, it is more complicated than that. In unpublished studies from Dr. Paul Cheney and Gordon Medical patients, approximately 40-50% of healthy family members and close contacts of people with CFS are infected with XMRV.
XMRV alone may not be sufficient to cause CFS in all people, but it appears it may be a necessary contributing factor, possibly in combination with another undetected retrovirus, another infection, or a genetic susceptibility to XMRV.
It is possible not everyone infected will develop disease in response to XMRV. In the case of HTLV, another human retrovirus, we see a similar pattern in that only 10% of infected patients develop clinical illness.
Since the original CFS paper published in Science magazine in 2009, several research teams have questioned the research of Mikovits, Lo, and Alter, perhaps due to concern about the consequences of the presence of XMRV in the nation's blood supply, and the high cost of screening our blood banks.
A recent flurry of papers attempted to debunk the XMRV research using the issue of possible mouse DNA contamination. The contamination concerns are generally valid, but the research done by the group for the Science paper, and the later paper by Lo and Alter had already taken steps to test for such contamination issues.
The contamination arguments, claiming the positive results are due to mouse DNA, cannot explain why positive samples show an immune response to XMRV, or why XMRV can be cultured from samples.
In addition, the samples were tested specifically for mouse DNA, in order to ensure there would be no contamination.
The contamination papers are not relavant to the most important studies indicating the finding of XMRV in Chronic Fatigue Syndrome, and the existence of XRMV still stands firm.
As of December 2010, the American Red Cross and international blood banks began banning blood donation from people with CFS. The government is currently working to develop a fast and accurate test for XMRV in order to protect the blood supply.
In unpublished research XMRV has been found associated with multiple other illnesses, including chronic Lyme disease.
It is associated with lymphoma, prostate cancer, inflammatory breast cancer, fibromyalgia, autism, Parkinson's, and Multiple Sclerosis, among other inflammatory conditions.
There is no proof yet that it is causative, but it is being found in higher numbers than would otherwise be expected.
Testing for XMRV has not proven easy. The Lo/Alter paper has shown there are many strains (mutations) of XMRV and related MLV viruses (such as PMRV).
Different strains of the virus can only be detected using the most sensitive PCR probes and under exacting conditions, often requiring culturing of the blood sample for several weeks to increase the viral numbers to detectable levels.
Testing is also complicated by the fact that XMRV can be undetectable in the blood, but may be found instead in organs such as the spleen, lymph nodes, and others.
Additionally, as in some other chronic infections, not everyone who is infected with XMRV produces antibodies, so tests that rely on measuring antibodies can produce *false negative* results.
Patients who are negative by PCR, may be positive by culture or serology/antibody, and vice versa.
Dr. Mikovits is currently working on a way to detect more of the strains of the MLV viruses in the XMRV family, as well as faster and more sensitive tests for both antibody and DNA of the entire family of retroviruses.
Patients who have tested negative for XMRV should realize that it is still possible they are infected, but it was not possible to find the infection in that sample on that day. Retesting on another day, or by another type of test, may give different results.
Samples from Gordon Medical patients who participated in the XMRV study through WPI are being used to help in the development of these new tests.
Dr. Mikovits is continuing to actively test any negative samples to ensure that any infections are found if evidence is present in the sample.
When viral evidence is found, WPI is sequencing the genetics to discover whether it is in this new family of retroviruses.
Dr. Mikovits stated that she expects to have a new, commercially viable test available by June of 2011.
Treatment Possibilities for the New Human Retroviruses
Are there treatments for XMRV? Will they help people with CFS, cancer, or other illnesses?
This is the hot topic that is still under investigation.
Doctors at Gordon Medical, the Whittemore-Peterson Institute, and a handful of other centers across the world are actively looking at possibilities.
At the time of writing, we know of approximately 65 CFS patients with XMRV who have tried various combinations of three anti-retroviral (ARV) medications originally designed for HIV: tenofovir, zidovudine and raltegravir.
Each drug has been proven to inhibit XMRV viral replication in in vitro (test tube) studies, and they are synergistic when any two drugs are combined.
Dr. Joseph Brewer is one of the primary clinicians doing trials with these medications. Dr. Brewer and other CFS doctors report that after 6 months of use, approximately 20-30% of patients on ARV's have noticed mild to moderate improvements.
Though these medications help some people, they are clearly not a complete solution for CFS and XMRV.
There is still a lot to learn about what doses, what combinations, and what supportive therapies might make them more useful for more patients.
Gordon Medical doctors, along with several other centers around the world are now looking at working with immunomodulating treatments such as Gc-MAF, stem cells, Peptide T and others that boost immune system function against viruses and cancers.
Dr. Paul Cheney is one of the pioneers of umbilical cord stem cells in the treatment of CFS and XMRV.
Based on 18 - 24 months of his experience with just over 30 patients, it is clear that stem cells produce dramatic improvements in most people under the age of 36, moderate results in the 36 - 60 year age group and mild improvements in those over 60 years of age.
Unfortunately, the good results are only temporary, lasting approximately 6 - 18 months before patients regress partially or completely.
Doctors at GMA are now investigating a technology related to stem cells called Platelet Poor Particle Rich Plasma that has proven beneficial to several hundred patients, some with conditions related to CFS, and will hopefully will have longer lasting effects than umbilical cord stem cells.
Another promising immune therapy is Gc-MAF (Gc protein-Macrophage Activating Factor).
Gc-MAF activates macrophages, which are immune system cells that are important in eliminating infection and cancer.
Unfortunately, many cancers and viruses cause the secretion of an enzyme called nagalase that digests naturally occurring MAF in our bodies.
Gc-MAF has a similar effect to that of our naturally occurring MAF, but Gc-MAF is not degraded by nagalase.
Administration of Gc-MAF via intra-muscular injection results in the reactivation of previously suppressed macrophages.
Gc-MAF was first used by Dr. Yamamoto in the treatment of HIV and cancer. Recently, approximately 80 XMRV positive CFS patients in Belgium and the U.S. have received Gc-MAF with very promising initial results.
Patients who are considering this therapy can be tested for nagalase levels as well as vitamin D receptor mutations, which may influence the outcome of Gc-MAF treatment.
Dr. Mikovits warns that it may be important to use an anti-viral strategy in addition to immunologic treatments that could potentially activate a reservoir in the body to express more virus. In addition to ARV pharmaceuticals, agents such as artesunate, nexavir and others have antiviral and anti- inflammatory properties that retard the growth of viruses.
Other factors that studies show may inhibit XMRV replication are restoring healthy glutathione levels, reducing oxidative stress, reducing inflammation, and normalizing methylation.
Few people realize that our body can naturally silence viral infections, including retroviruses such as HIV and XMRV, through methylating viral DNA.
Conversely, if viral DNA is not properly methylated, viruses will continue to reproduce and grow in our bodies.
We know that almost everyone with CFS has a methylation cycle abnormality that can be improved by taking methylation enhancing nutritional supplements.
The study that proved this concept was co-written by GMA's very own Neil Nathan, MD. Most people with CFS have mild to moderate improvement in symptoms when on methylating factors.
Some very sensitive patients find that starting methylation supplements can exacerbate symptoms, so as with all treatments, it is important to do these in close consultation with your physician.
Viruses replicate more quickly in environments of oxidative stress and inflammation. They also grow more easily in low-glutathione environments.
As an adaptive mechanism viruses actually cause oxidative stress, inflammation, and low glutathione levels in our bodies that favors their survival.
By replenishing glutathione levels and reducing oxidative stress and inflammation, we may inhibit viral growth.
Many natural compounds have anti-inflammatory properties. One group of compounds that has proven to inhibit both the herpes viruses and the NF-kB inflammatory pathway is artesunate and related artemisinin derivatives.
Dr. Mikovits and the doctors at Gordon Medical believe it will be important to diagnose and treat co-infections in patients infected with XMRV, just as it is with HIV.
In the Gordon Medical cohort so far approximately half of the patients who are positive for XMRV also have Lyme disease. Many also have EBV, HHV-6 and CMV, and other infections.
Some patients who are diagnosed with *CFS* respond partially or completely after treating the Lyme disease.
Other patients experience benefits by taking valtrex, valcyte or other antiviral medications active against herpes-viruses. Though valtrex and valcyte do not usually cure CFS, they can help people feel better by reducing the immune system load imparted by viral co-infections.
Studies have shown that hormones such as cortisol, testosterone and estrogen can promote XMRV replication.
Each of these hormones performs critical functions in our body, so some amount is needed, but in excess, or out of balance, they may be harmful.
Cortisol is produced in response to stress, and most people with CFS are familiar with how stress impacts their symptoms.
Estrogen, progesterone, testosterone and DHEA are often low or out-of-balance in CFS. Some patients feel better on low-level supplementation of these hormones, but some worsen. It is important to pay close attention how one's body responds to hormonal shifts in order to stay in balance.
The good news is that with every passing year, our understanding of CFS is getting better and better. Though CFS is still a challenging illness to treat, recently discovered treatments have resulted in marked improvements in a growing percentage of patients with CFS, which represents a significant advance compared to years past.
It is important to remember that each of the therapies mentioned in this newsletter are experimental.
There are no published clinical trials yet, only informal observations made by groups of astute doctors and patients.
The practitioners and staff at GMA thank you for your time and interest.We will continue to collaborate with the Whittemore-Peterson Institute and share the latest advances in CFS and XMRV research.
We would also like to extend our appreciation and gratitude to the courageous patients dealing with CFS, XMRV, chronic Lyme disease and related illnesses who have maintained hope, raised awareness and pushed us forward.
Dr. AzRa MaEl, MD Dr. Schaller would like to thank this source: Susan Friedl, Research Coordinator, Gordon Medical Associates
DR. SCHALLER NEITHER SUPORTS NOT OPPOSES THIS INFORMATION, AND INVITES YOU TO WORK WITH YOUR RESEARCH ORIENTED CLINICIAN TO SEE IF THIS MIGHT BE PART OF YOUR SUFFERING IN THE COMING YEARS.
IN THE END, DR. SCHALLER FEELS THIS TYPE OF RESEARCH WILL HELP SOME PATIENTS.
WHAT TYPE OF PATIENTS AND TO WHAT PERCENT THEY WILL BE HELPED APPEARS WILL BE UNFOLDED SLOWLY AND SOBERLY WITH HUNDREDS OF RESEARCHERS INVOLVED TO REACH CLINICAL HUMAN TREATMENT.