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vrijdag 31 december 2010

SSH..... MBNY!



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The editor of *Help ME Circle*
wishes you a Much Better New Year!







~jan van roijen


















~~~~

The Race Is On in XAND Land


Judith Mikovits,
Whittemore Peterson Institute




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http://pharmaceuticalvalidation.blogspot.com/2010/12/race-is-on.html




Pharmaceutical Validation


validation refers to establishing documented evidence that a
process or system, when operated within established
parameters, can perform effectively and reproducibly to
produce a medicinal product meeting its pre-determined
specifications and quality attributes



``````````````````````


By Walter Armstrong




"I really, really, really want to die and have had enough
of being so sick and in so much pain every second of
every day and, basically, one serious health crisis after
another,"
wrote Lynn Gilderdale in a 2006 Web post during one
of many discussions the 31-year-old British woman had with
parents and friends on whether to hasten her own death.

In July 2009, Gilderdale decided to act, injecting herself with
what she believed to be a lethal quantity of morphine. An hour
later, she was unconscious but still alive, so her mother, Kay,
took over the duty of assisting her daughter's suicide.

She crushed antidepressants and sedatives and inserted the
powder into her daughter's nasogastric tube.

When that remedy failed, Kay gave Lynn several more
injections of morphine, and later, increasingly desperate,
several injections of air.

Finally, toward dawn, Lynn's spirit made good her longed-for
escape from a body ravaged for 17 years by severe chronic
fatigue syndrome (CFS).



The Gilderdales' personal tragedy became a public story
following Kay Gilderdale's arrest for attempted murder.

With the British government inching toward legalizing assisted
suicide, Lynn's CFS-related loss of almost every physical
function, coupled with her mother's steadfast devotion,
rendered the Gilderdales the most sympathetic in a series of
highly publicized right-to-die cases.

In January, a British jury unanimously found Kay Gilderdale not
guilty of attempted murder. Her exoneration marked a triumph
for advocates of the legalization of assisted suicide.

But lost in that debate was what patients with CFS view as a
more urgent story:

The disease that took Lynn Gilderdale's life
remains as untreatable in 2010 as it was when
the first known outbreak occurred in Lake Tahoe
in 1984.




"CFS simply gets no respect. It has been underfunded,
understudied, underdiagnosed, and the healthcare system
would like nothing better than to sweep it under the rug,"
says
Donnica Moore, a women's health expert and CFS advocate.

"But we're not going to allow that. "Medicine's "Problem
Child"




From almost any angle, CFS presents a vexing picture. No
cause-not even a single biomarker-has been identified.
Symptoms are as diverse as they are unpredictable, including
debilitating fatigue, post-exertion malaise, and an enduring
flu-like state ranging from aches and pains to severe
headaches, cognitive disturbances, paralysis, and myriad
complications.

"CFS defies the established structure of medical disease,"
says Kimberly McCleary, who has headed the CFIDS
Association of America for 20 years. "Many doctors still don't
'believe' in it. They treat a single symptom without seeing the
whole. Or, worse, they dismiss it as a psychological problem."

In turn, a fierce mistrust of not only the medical profession
but the federal research establishment is endemic in the CFS
community. Conspiracy theories abound.



Some 200,000 Americans have been diagnosed with CFS, while
anywhere from 1 million to 4 million may suffer from it,
according to the CDC.

Average life expectancy is about 55, with suicide the third
most frequent cause of death. Depression is rampant. "CFS is
not a death sentence-it's a life sentence," is a CFS
community truism.

Meanwhile, skeptics persist in dismissing it as "yuppie flu" and
"shirker syndrome." Yet recent studies show that most CFS
patients did not experience clinical depression prior to getting
sick.

And increasing diagnoses of pediatric and adolescent cases
reveal that kids who fall victim to the disease include many
high achievers, whose parents can trace the onset of the
illness to a routine infection of unusual severity or duration.


Still, the CDC's sole treatment recommendation
is cognitive-behavioral therapy. The agency's
longtime CFS program head was finally axed in
February, following years of public criticism by
doctors for favoring a research focus on early
sexual abuse rather than the search for
pathogens.


The tenacity of its "disputed diagnosis" status has earned CFS
the dubious distinction as the only orphan disease with
literally millions of "silent sufferers."

Pharma's longstanding disinterest in CFS is predictable, given
the disease's unforgiving uncertainties. "I don't blame the drug
industry-CFS is medicine's 'problem child,'" says virologist
Suzanne Vernon, the CFIDS Association's scientific director. "If
so many doctors do not recognize CFS, how can a drugmaker
sell a treatment?"



CFS presents a kind of Gordian Knot to any pharma wishing to
brave clinical trials: the lack of a biomarker confounds
diagnosis; the lack of quantitative measurements of
fatigue-the telltale symptom-confounds evaluation of a
drug's efficacy; the presence of such diverse symptoms
confounds validation of data.


"The drug industry works best on a 'bug and drug' model, and
CFS has been slow to deliver a target," says McCleary. Early
on, hopes were high that basic science would uncover a single
virus behind CFS's devastating immune-system collapse-as
took place in HIV.

Academic research into the human retrovirus HTLV-II yielded
especially promising preliminary results in 1991, raising
patients' hopes, but replication studies foundered and funding
was cut.



Until now, pharma's contribution to CFS treatment has been
largely limited to the off-label use of a panoply of drugs, such
as stimulants, sedatives, antidepressants, and anti-migraine
medications to treat symptoms. However, with the success of
Lyrica and Cymbalta for fibromyalgia (another "disputed
diagnosis") drugmakers may find themselves inching into the
CFS market.


Pharma may in fact stand to gain considerably by investing in
CFS R&D. Expert consensus is that CFS is actually a suite of
diseases, with some overlapping symptoms but many
differences-and multiple causes.
Advanced research is identifying biological trends, including
chronic low-grade immune activation, latent activation of
infections, and specific abnormalities in cognition, metabolism,
and blood pressure. Deeper forays into CFS pathogenesis could
yield finds that apply to many other conditions.


"CFS is a huge opportunity for pharma,"
says Moore. "The
market is big, the bar is low, and they don't need a home
run. Even incremental improvements to quality of life would
be fantastic."



Unfortunately, the first CFS drug to face FDA review bombed in
December: Hemispherx's sloppy NDA for Ampligen, an antiviral
and immune booster in experimental use since the late '80s,
contained 15-year-old data that "did not provide credible
evidence of efficacy.

"The drug, which requires twice-weekly IVs and costs
thousands of dollars a month, appears to work well in about
15 percent of patients. "This is the right drug in the wrong
hands," says McCleary. "They cut too many corners."




In XAND Land

Into this bleak landscape last October blazed an unpredictable
claim by an obscure researcher from a little-known institute
that the cause of CFS may have been discovered: a human
retrovirus called xenotropic murine leukemia virus–related virus
(XMRV).

Biochemist Judith Mikovits at the Whittemore Peterson
Institute (WPI) in Reno, NV, along with colleagues at the
National Cancer Institute and the Cleveland Clinic, reported in
the journal Science that DNA from the mouse-derived
retrovirus were found in 67 out of 101 blood samples of CFS
patients.

Testing of 300 additional samples was said to hit 98 percent.
What's more, 3.7 percent of the 218 control samples also
contained XMRV.


The media predictably amplified the remarkable, if preliminary,
findings into a "cause-of-CFS" story, and WPI was only too
happy to oblige.

"This is the breakthrough that we have been hoping for.
Now we have scientific proof that this infectious agent is a
significant factor in CFS," Annette Whittemore, WPI founder
and president, proclaimed in the initial press release, which
also announced that WPI had renamed CFS as
XMRV-associated neuro-immune disorder (XAND).



WPI did not discover the XMRV virus, however. That distinction
goes to scientists at the Cleveland Clinic and the University of
California San Francisco, who in 2005 detected this fourth
human retrovirus in the cancerous prostate tissue of 40
percent of men with a particular defective gene.


WPI's Mikovits made the opportune leap from prostate cancer
to CFS when she learned of the high incidence of lymphoma
among the original Lake Tahoe cohort.

XMRV seemed a possible culprit because it decimates natural
killer blood cells, the immune defense against cells infected by
HTLV-I.

In addition, some CFS patients carry the same genetic
mutation as men with prostate cancer who tested positive for
XMRV.

The working hypothesis at WPI is that XMRV indirectly causes
CFS by inflicting so potent an assault on the immune system
that it reactivates other viral infections and a chronic
inflammatory response.

"XMRV is the sort of agent that could create that effect on
the immune system," Daniel Peterson, WPI's medical director
and the co-discoverer of the original Lake Tahoe outbreak, told
The New York Times in a piece headlined "A Big Splash by an
Upstart Medical Center."



WPI was founded in 2006 by Whittemore and her husband,
Harvey, a prominent Nevada couple whose daughter, Andrea,
31, has lived with a severe case of CFS for 20 years.
Frustrated by Andrea's marginalization by doctors and by the
lack of leadership, funding, and research at CDC, Annette
Whittemore invested $5 million to launch her own research
institute at the University of Nevada Medical School in Reno.



A flurry of activity followed on the heels of the discovery.
Other researchers raced to confirm the WPI study. Patients
flocked to the Internet for more information:

Was XMRV fatal? How was it transmitted? Could they
get tested for it?


The answer to the last question was yes. A diagnostic test for
the virus was already being marketed at $650 a shot by VIP
Dx, which just happens to be owned by Annette and Harvey
Whittemore.

"Leaving aside the issue of who's right and who's wrong, the
original paper did not establish the virus [causes CFS] and
didn't establish it as a viable marker,"

Tufts University retrovirologist John Coffin, who wrote the
editorial accompanying the original Science study, told the
journal. Nevertheless, VIP Dx reported a six-to-eight-week
backlog for results.


In general, patients' emotions bordered on the euphoric. Cort
Johnson, whose Phoenix Rising Web site is one of the most
trusted sources of information in the CFS community, says,
"Patients are starved for good news. A discovery like this
excites researchers, brings in funding, and gives patients
hope-something they haven't had for many years."

Meanwhile, the nation's handful of CFS specialists tried to
temper patients' expectations with YouTube educational
lectures on XMRV and its potential treatment implications.


For public health officials, the most alarming
data point was XMRV's 3.7 percent prevalence
rate in the control group.

Extrapolating a worst-case scenario led to the prospect that as
many as 10 million Americans could be carrying an infectious
retrovirus already linked to two serious diseases.

In January, a federal task force was convened to safeguard the
nation's blood supply, an operation that could take a year or
more, according to member Suzanne Vernon. Then again, a
little public panic has its upside. "As we saw in the early years
of HIV, fear among the general population at least gets the
money flowing," says Moore.




A Pharma Screening


XMRV is exactly the kind of bug that hooks Big Pharma. "Two
of the world's biggest drug companies contacted us the day
our Science paper appeared," says Judith Mikovits.

"By showing that XMRV is an infectious agent, we think we've
convinced them to become interested in this target." Although
Mikovits refused to disclose the identity of the two
companies-"for fear that patients might seek out the
treatments before studies"-she said that both were already
screening HIV antiretroviral compounds in WPI cell lines for a
hit.


Given the similarities among human retroviruses, an HIV
drugmaker may already possess an effective anti-XMRV
agent-if not a drug already on the market, then one of the
thousands of marginally variant molecules made in the
painstaking process of discovery-and currently gathering dust.
Two classes of HIV drugs are in the running.


Both HIV and XMRV replicate by virtue of reverse
transcriptase, the enzyme that links their viral RNA to the host
cell's DNA. Reverse-transcriptase blockers were the first victory
Big Pharma scored against HIV.

Ironically, in the February Virology, Mayo Clinic researchers
reported that after testing 10 HIV drugs against XMRV in vitro,
the virus was susceptible only to AZT, a nucleoside
reverse-transcriptase inhibitor (NRTI) notorious for its toxicity.

"No CFS patient wants to go near AZT," says Mikovits.

Other RTs (or experimental versions) that may show promise
include Bristol-Myers Squibb ddI and d4T, GlaxoSmithKline's
Ziagen, and Gilead's Emtriva and Viread.

Merck's first-in-class integrase inhibitor, Isentress, may work
"because of its broad-spectrum activity," according to Coffin.

In the best case, an already-approved antiretroviral will reveal
XMRV-busting prowess, allowing the drugmaker to bypass
safety and other early tests and advance straight into humans.

"If one of the drugmakers currently screening candidates gets
lucky, we could start a clinical trial in a month," says Mikovits.


Veteran advocates like Kimberly McCleary do a double-take at
the news that two global pharmas are on the trail of CFS.
"Now what we need is a race between them to see which can
be first to market," she says.




WPI and Full Disclosure


When XMRV was first discovered in 2005, pharma held back
because it was reported that the virus appeared to be inactive
in prostate cancer cells.

But Abbott Diagnostics jumped at the challenge of developing
assays to detect XMRV. Last month, Abbott HIV Global
Surveillance Program's John Hackett reported early progress on
several fronts.

But the main takeaway was that detecting XMRV in human
blood samples is proving far more difficult than the WPI study
had led anyone to expect.

Using their new assay that can detect three different antibody
proteins, the Abbott team found XMRV in only three of 2,851
random human samples. That's good news for the general
population-a .01 percent extrapolated prevalence rate-but
bad news for CFS patients.


Nor is Abbott alone in judging XMRV hard to find. Since
January, three confirmation studies-two British, one
Dutch-have reported results, and none found the retrovirus in
either their CFS blood samples or their controls.

As doubt is increasingly cast on WPI's theory that XMRV
causes CFS, arguments have raged across the Atlantic.
Accusations of sloppiness, bias, and even fraud have been
hurled, mostly by Judith Mikovits and WPI's defenders. Old
suspicions of patients have reappeared.


When asked for a more considered opinion, others choose their
words carefully. "Validation and confirmation are not coming as
fast as one might like, that's for sure," says John Coffin. "If
you can't establish a disease association, then there is less
interest in developing a drug, obviously."

Coffin also notes that uncertainty remains about whether or
not the virus is replicating. "If it does so, like HIV, then an
antiretroviral would be very effective. But if not, as it appears
in prostate cancer, a drug would not make any difference."


Writing on the CFIDS Association of America's Web site,
Suzanne Vernon made a valiant effort to keep hope in the
causal hypothesis flickering by emphasizing that none of the
three studies is a "proper and robust replication study."

And she concluded by throwing down the gauntlet: "Until
methods are standardized and the scientific community is
provided information about the specific characteristics of the
CFS subjects who tested positive in the Science paper, be
prepared to read more negative studies.

Hopefully the Science investigators will make this information
available before interest in XMRV being associated with CFS
fades."

Given the great diversity in CFS symptoms, disclosure of the
medical histories and clinical conditions of the high number of
WPI's XMRV-infected CFS patients is critical. "Of course, this
would generate more questions, but a cleaner association is
needed," Vernon says. "I don't know why WPI won't provide
this."


So far, Mikovits has refused to budge. "No additional medical
histories or anything about the patient population would shed
any light on XMRV," she says.

Sleuthing on her own, Vernon was able to uncover some
suggestive information about the 32 CFS patient samples
about which WPI originally reported assay results. Only 12
tested positive on more than one assay (WPI ran four assays);
of those 12, four had been diagnosed with cancer. Another 13
of the total 67 XMRV-positive CFS samples also had cancer.


Whether XMRV is a cause or a passenger or merely a
geographical coincidence of a particular CFS outbreak remains
to be learned.

But one thing is clear: With its big discovery, the upstart
medical center has made more than a big splash. WPI has
placed CFS-and itself-at the center of the perfect storm.


"I knew how serious a retrovirus is," Annette Whittemore told
the Times. "I was very concerned, knowing the implications.
My second thought was, 'Of course, it was going to be
something serious like that. Look at my daughter and how ill
she is.'"








~~~~

woensdag 29 december 2010

Lyme, (CFS, FM), XMRV -ILADS 2010 Conference Takeaways




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Special Edition










Quote from Dr. Joe Brewer:



*....In one autism study, all mothers tested were XMRV
positive and many of them expressed symptoms of Chronic
Fatigue Syndrome or Fibromyalgia....*



~jan van roijen




``````






http://bit.ly/eNuKYO



[]







Thursday, December 30, 2010



ILADS 2010 Conference Takeaways




In October 2010, I attended the ILADS [http://www.ilads.org/]
2010 Annual event. The event was packed. Almost 400 people
attended in person and over 1,000 people watched on the live
webcast. It is exciting to see so many people taking an
interest in this controversial area of medicine. The event was
full of great information and people working hard to help us all
find answers.



In this blog entry, I will share a few of the key takeaways that
I learned at the event. The slides from the event are
available for purchase here for a very reasonable $40. The
DVDs (Friday's sessions) and CDs of the presentations can be
obtained from ZenWorks Productions.

Thus, I am not going to attempt to repeat information that is
available elsewhere, but I will focus on some of the key things
that caught my attention.



* The 2011 ILADS event will be in Toronto, Canada -
October 28-30, 2011




* Dr. Richard Horowitz proposed that Chronic
Lyme is really MCIDS - Multiple Chronic Infectious
Disease Syndrome



* Biofilm treatment may be with EDTA or a
Banderol/Samento combination. There may be a strong
antigen release with biofilm treatment which may make it a
good candidate for pulsed therapy

* Dr. Steve Harris mentioned that yeast may cannibalize
dying Borrelia and that yeast is not always the result of
antibiotic therapy alone. He suggested up to 100 billion
probiotic organisms daily. In terms of diet, he said, "If it's
white, it ain't right"

* Minocycline may have longer toxic effects than
doxycycline but has better CNS penetration. Mino also has
less sun sensitivity than doxy. That said, Dr. Joe Burrascano
commented that the effectiveness of minocycline may be
regional as he never observed it working well in his patients

* Tygacil can be difficult to tolerate but has emerged as an
excellent tool for some patients in the treatment of chronic
infections




Dr. Joe Burrascano shared:


* New pathogens will likely continue to be discovered such
as XMRV / HGRV

* Biofilm-busting treatments are just the beginning of what
will come

* When Borrelia is the only infection involved, the onset of
symptoms is slow. There are no sweats. A 4-week symptom
cycle is observed. There is often joint involvement, swelling,
and stiffness. Temperature may be high in the late afternoon
but low in the morning. Headache is often in the back of the
head

* CD57 suppression may occur in XMRV as well as in
Borrelia. (Editor's Note: There was also talk at this event of
Chlamydia pneumoniae causing CD57 depression as well as a
discussion of CD57 going down when one is in the midst of a
Herxheimer or die-off reaction. Thus, it seems that CD57 may
not be as specific for Borrelia as may have been previously
believed. That said, I do still believe it is an important marker
to help provide additional insight as to whether or not
someone may have Lyme disease and when they may be able
to stop antibiotic therapy with a lower possibility of relapse.)

* If a relapse occurs within 3-4 weeks after stopping a
therapy, this may be Borrelia. Anything sooner would more
likely indicate a co-infection
* Bartonella may result in light sweats, CNS/Brain
involvement, anxiety/rage, sore soles of feet in AM, 99.5
temperature in AM and normal in afternoon, lymph gland
involvement, elevated VEGF, seizures, feeling rev'd up,
gastrointestinal complaints, and nodules under the skin

* Babesia may result in abrupt onset of symptoms,
symptom cycles of every 3-7 days, fatigue, global headaches,
dry cough, air hunger, and coagulation cascade irregularities
being triggered. When Lyme disease is really bad, Babesia is
likely a co-factor

* Ehrlichia may result in abrupt onset of symptoms, muscle
involvement, high fevers, low WBC and platelet counts

* Rocky Mountain Spotted Fever (RMSF) results in a spotted
rash including on the hands and soles of the feet

* Mycoplasma does not currently have any good tests
available. It is a common lab contaminant which makes
testing difficult. Leads to neuropathy and fatigue. Infects the
mitochondria of the cells and leads to the sickest and most
chronic patients. He mentioned that building the immune
system and getting rid of Lyme is often the focus here rather
than going after Mycoplasma specifically

* C6 ELISA is generally never positive in chronic Lyme and
not useful as a result

* Spinal taps are done to look for OTHER things; not to look
for Lyme

* Stonybrook has a good Western Blot but only reports all
bands when requested; otherwise reports CDC bands which
exclude the most important 31 and 34 bands

* Flagyl must be taken for 14-30 days minimum to have any
impact on Borrelia

* If someone has chronic Lyme but does not do IV therapy,
the chances of them recovering are small

* Never taper the dose of antibiotics. When it is time to
stop, stop. Tapering off may create resistant organisms

* Exercise is a key to recovery

* In chronic Lyme patients, 100% may be XMRV / HGRV
positive

* Kefir is an excellent source of probiotics




````````````
* There was some discussion from Dr. Fry's talk (which I
was unable to attend) that decreasing lipid intake may be
helpful. I'm hoping to understand this more from the audio
CDs of the talk. There was also discussion that Magnesium
stearate can increase the amount of biofilm

````````````




* Dr. Richard Horowitz mentioned:


o He has had success with IV Glutathione for
detoxification - helps with fatigue and depression and
improvement is often observed within minutes

o Almost every Lyme patient is testing positive for
heavy metal toxicity

o 40% have adrenal dysfunction

o The Western Blot from IGeneX has both B31 and 297
Borrelia strains where many other labs use only B31 which
makes their Western Blots more likely to result in a false
negative

o Mepron and Malarone dosages may need to be
increased to higher dosages than previously used. Mepron - 2
teaspoons twice a day with Septra or Bactrim may be useful
for Babesia. Malarone may require 4 tablets daily with
artemisia. Coartem (Riamet) can be done as a 3 day pulse per
month and has been very helpful for some patients

o Bartonella can have significant eye-related symptoms

o Gentamicin is bacteroicidal

o Bartonella infection has been found in newborn
children resulting from pregnancy

o Probenecid may help reduce Quinolinic acid - a toxin
produced by Borrelia

o 200 billion probiotic organisms daily is often
necessary





* Paul Ewald suggested that microbes that cannot
transmit frequently favor persistence in the body (i.e. sexually
transmitted microbes do not have the same opportunity to
transmit vs. airborne microbes which much more easily
transmit from one person to another). He lectured on the
connection between many chronic illnesses and chronic
infections




* Dr. Ray Stricker shared the following on the
topic of testing:



o Band 39 is the most specific for Borrelia

o IgM Western Blot has more possibility of a false
positive result than the IgG Western Blot

o CD57 may be affected by Borrelia, Chlamydia
pneumoniae, and Tuberculosis

o CD57 will generally go down within 3 months of
infection

o According to Dr. Stricker, the test is valid for children
(though responses may be exaggerated) though Dr. Jones
shared that he did not find it to be very helpful with children

o CD57 may go down with Herxheimer reactions.
Inflammation may result in a drop in CD57

o Elevated CD57 such as 400 may occur. HIV patients
do exist with high CD4 counts as a corollary though the CD4
cells may not work well or function properly. Thus, CD57 can
tell us the quantity of the cells but the issue may be the
quality or whether or not the cells can function optimally.
(Another practitioner suggested that many cases of high CD57
show drops in CD57 results once treatment begins)

o Stem cell therapy is not known to affect CD57 counts
though another practitioner commented that she had seen an
initial drop in CD57 after stem cell therapy with continued
ongoing increases as time passed after stem cell therapy

o C4a is an inflammation marker. It generally
correlates with symptom presentation

o C3a is an autoimmune marker

o C4a can be due to infection





Dr. Norton Fishman shared information on the
immune system and cytokines:



* Noted that Lyme is a "politically incorrect illness"

* Dr. Herxheimer died in a Nazi concentration camp

* One of his diagnostic criteria for Lyme patients is a
person that feels that each time they take antibiotics, they
get sick. Generally, this is not an allergic reaction, but a
die-off reaction.

* There is an exacerbation of inflammation with a herx
reaction. Some herxes are more mild and may suggest that
you are on a good path much like a speed bump. However,
when a speed bump in the road becomes a guardrail, you have
a problem

* Opportunistic infections may not do much while the
"police are are on the street" or the immune system is on
alert. Some Lyme patients don't get colds or flu. When
treatment begins, opportunists may emerge

* When a herx is too much, pulling back on the therapeutic
throttle is often appropriate. There is no place for heroes in
this disease. Herxes can be terribly damaging

* Some agents will slow the inflammatory reaction such as:
Willow Bark, Omega-3, zinc (many are zinc deficient),
turmeric, ginger, licorice root. Many of these quiet down
NFK-ß. Probiotics help dampen the cytokine response in the
gut. His favorite is Vitamin D3

* Vitamin D3 is turned by liver into D,25 which is converted
to D1,25. Macrophages increase Vitamin D1,25 production
when activated. Many Lyme patients have high D1,25 and low
D,25 which indicates they have infection. D1,25
downregulates the pro-inflammatory cascade and makes
peptide antibiotics. People with higher Vitamin D levels have
fewer infections such as TB and flu

* Many people experience a "herx" when they get "Lyme 2"
on top of "Lyme 1". Immune memory of "Lyme 1" explodes
when "Lyme 2" is introduced. The response is much more
exaggerated with the second Lyme infection than the first.
Once new antigens are introduced, the patient may become
much sicker

* People with Lyme are mosquito and tick-attractive; likely
related to a pheromone




Eva Sapi, PhD talked about the many exciting
projects that her team is doing:



* They are looking for XMRV in ticks to see if the retrovirus
may be transmitted by tick exposure

* They did some excellent research showing Samento +
Banderol + Serrapeptase (all from NutraMedix) had very
significant biofilm eliminating effects




Dr. Joe Brewer spoke on the topic of XMRV:


* Endogenous retroviruses are viruses that we all have.
These cannot complete replication and are not infectious.
They are something that we inherit in our DNA

* Exogenous retroviruses are viruses that can replicate
outside of the cell and are infectious

* Xenotropic (as in XMRV) - the virus does not complete its
life-cycle in the mouse but does in humans

* XMRV is a much simpler virus than HIV

* XMRV does incorporate itself into our DNA

* XMRV uses a receptor X-pr1 that is present on all human
cells and thus can infect all human cells

* We now have both X-MLV (xenotropic mouse leukemia
virus) and P-MLV (polytropic) forms of the virus

* In CFS, both X and P have been observed

* In HIV, HAART (Highly Active Antiretroviral Therapy)
therapy is a three-drug (generally) combination used for
treatment of HIV

* In one autism study, all mothers tested were XMRV
positive and many of them expressed symptoms of Chronic
Fatigue Syndrome or Fibromyalgia

* In a small sample of MS (4), Parkinson's (1), and ALS (1)
patients, 100% of those tested were positive for XMRV

* In chronic Lyme disease, over 90% of those tested were
positive for XMRV

* How XMRV is transmitted is still not fully understood but
we do have HIV as a model. Blood transfusion, sexual
transmission, and needles may be mechanisms. They are not
seeing rampant CFS in gay men or prostitutes so there must
be other mechanisms. One German study showed XMRV was
found in saliva. There is little doubt that in-utero and breast
milk transmission is possible. One unknown is whether or not
ticks may also have XMRV and could they transmit XMRV to
humans? That work is being done by Eva Sapi, PhD and her
team

* Current possible treatment options for XMRV include:
Zidovudine (Retrovir), Tenofovir (Viread), and Isentress
(Raltegravir). All two drug combinations worked better than
any single drug

* There is not a perfect testing method for XMRV

* XMRV often gets worse at the onset of treatment and
treatment has been a mixed bag thus far. Tests are needed
to monitor treatment progress. The P-variant may require
entirely different anti-retroviral medications

* Known inducers of XMRV/HGRV activity include: NFK-ß,
possibly treating Lyme with antibiotics leading to a strong
herx which results in inflammation could increase the
replication of XMRV, glucocorticoids activate viruses
(cortisol/stress), and androgenic hormones. I was struck by
the comment that a Herx reaction from Lyme treatment may
actually increase the activity of XMRV



````````````
During Q&A, Dr. Fishman acknowledged the
politics involved in Lyme disease. He suggested
that XMRV may be the pathway that we should
pursue in order to benefit ourselves

````````````



Dr. Richard Horowitz did a lecture on integrative treatment
of Lyme disease which was one of my favorite lectures. I would
highly recommend getting the audio recording of his session
as it was one of the best. I don't begin to touch on the
wealth of information that he shared over this two+ hour talk.
He shared the following (and much more):


* He suggested we need to broaden our view of Lyme
disease and look at all of the other factors involved. He
suggested that it is like having 14 nails in your foot - you
need to pull out all 14

* In 5,000-6,000 patients tested, everyone is "loaded" with
heavy metals such as mercury and lead
* Most "sickness behavior" (i.e. what makes us feel sick;
symptoms) is the cytokines. Glutathione reduces this in
minutes in many patients

* 1/3 of his patients have had a severe history of abuse;
these emotional traumas need to be dealt with in order to
recover. These are the most resistant patients. When the
trauma is cleared, the patients improve. He mentioned a
technique called "The Journey" (http://www.thejourney.com)

* 40% of patients have adrenal dysfunction which must be
addressed; patients will not respond to antibiotic treatment
without adrenal support

* 70% of patients have peripheral neuropathy

* Low Dose Naltrexone (LDN) can be very helpful in
lowering cytokines and thus relieving many symptoms
associated with the disease. Always remember the cytokines.
LDN can be a big help here

* Bicillin is one of the best antibiotic options at 1.2 million
units 2-4 times per week

* Biaxin XR is better than Biaxin

* Grapefruit Seed Extract can be an effective cyst buster

* When using Flagyl, supplemental B-vitamins may be
helpful to avoid peripheral neuropathy

* A combination such as Doxycycline or Minocycline with a
macrolide and Plaquenil may be a good option. Plaquenil
alkalinizes the intracellular compartment

* You cannot combine a macrolide with a quinolone

* Magnesium and Alpha-lipoic acid taken away from a
quinolone may be helpful in reducing the risk of tendon
damage

* Factiv is a newer drug sometimes used for Bartonella that
is generally tolerated well

* Mepron resistance is becoming a problem and 1 teaspoon
twice daily is no longer working

* The goal is not to "cure" or "eradicate" but to lower the
load so that the immune system can manage. We will not
eliminate all of these organisms entirely from our bodies

* Mepron plus Sulfa/Bactrim; or Malarone (up to 4 tablets
daily) plus Artemesia may be useful for Babesia. No CoQ10
can be used with Mepron or Malarone

* Coartem (Riamet) is a new option in the US for Babesia.
It is a 3-day course. No macrolides, no QT-interval impacting
drugs, no Plaquenil, no Mepron/Malarone for a period before,
during, and after the Coartem; works well, but the Babesia will
still come back

* Babesiosis is extremely difficult to "cure" (i.e. fully
eradicate)

* Olive leaf is a good option for viruses

* For Candida, oregano, garlic, caprylic acid, Pau D'Arco,
and berberine may be useful

* Autoimmunity is likely driven by intracellular bugs such as
Mycoplasma

* Alpha-lipoic acid pulls metals and regenerates glutathione

* Quinolinic acid (QUIN) is a major neurotoxin in Lyme
disease

* For environmental toxins, far infrared sauna can be a
good option

* Up to 25% of patients with MCIDS (Multiple Chronic
Infectious Disease Syndrome) improve on a metal
detoxification program. This may also be related to
autoimmunity

* Detoxamin or oral DMSA may be used for heavy metal
detoxification

* Xymogen MedCaps DPO (dual-phase optimizer) can be a
useful detoxification support option

* Environmental chemicals can be tested for with
Accu-Chem / MetaMetrix

* Glutathione can be used for quinolinic acid or for
cytokines
* On the Cowden Protocol: Glutathione works better than
Burbur or Parsley in his experience and he did not find the
protocol to have a strong enough effect on Babesia.
Otherwise though, Dr. Horowitz reports very positive results
with the Cowden Protocol

* Take-home message: DETOXIFY YOUR LYME PATIENTS!

* It does NOT matter what antibiotic you give people, they
will NOT get better without detoxification

* For Herxheimer reactions: 2 Alka-Selzer Gold (no
aluminum) in 8 ounces of water with lemon or lime followed by
6-8 capsules of glutathione or 1500 mg or oral liposomal
glutathione. 70% will feel better in hours

* On the topic of water: Dilution is the solution to
pollution. This suggests that in order to help our bodies
detoxify, we must drink more water

* His goal of treatment is to get off antibiotics as soon as
possible and that is why he is so interested in the various
herbal protocols such as Cowden and Buhner but he believes
that it is critical for scientific studies to be done in these
areas




````````````

ILADS 2010 was a great event full of great people
looking for answers. I can't wait for the 2011
event!




Note: Please contact me
[http://betterhealthguy.com/joomla/contact] if any errors,
omissions, or misstatements are identified in the content
above.


My apologies in advance to any presenter that I may have not
accurately reflected above.







~~~~

dinsdag 28 december 2010

How did XMRV enter the human population?


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Send an Email for free membership
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For private members the Provisional PDF file is attached;
others can download the full text via the abstract site,
because the mentioned URL doesn't work.

http://www.frontiersin.org/virology/10.3389/fmicb.2010.00147/abstract




~jan van roijen




````










Of mice and men:
on the origin of XMRV


Antoinette Cornelia Van der kuyl,
Marion Cornelissen and Ben Berkhout


Journal Name: Frontiers in Microbiology
ISSN: 1664-302X
Article type: Perspective Article
Received on: 20 Sep 2010
Accepted on: 26 Dec 2010
Provisional PDF published on: 26 Dec 2010


Frontiers website link: www.frontiersin.org

Citation: Van der kuyl AC, Cornelissen M and Berkhout B
(2010) Of mice and men: on the origin of XMRV. Front.
Microbio. 1:147. - doi:10.3389/fmicb.2010.00147

http://www.frontiersin.org/virology/10.3389/fmicb.2010.00147/abstract

s=1161&name=virology&ART_DOI=10.3389/fmicb.2010.00147

(If clicking on the link doesn't work, try copying and pasting it
into your browser.)




Perspective


Of mice and men:
on the origin of XMRV



Running title:

How did XMRV enter the
human population?



Antoinette C. van der Kuyl, Marion Cornelissen
and Ben Berkhout


Laboratory of Experimental Virology, Department of Medical
Microbiology, Center for Infection
and Immunity Amsterdam (CINIMA), Academic Medical Center,
University of Amsterdam,
Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands






Abstract


The novel human retrovirus XMRV (xenotropic murine leukemia
virus-related virus) is arguably the most controversial virus of
this moment.

After its original discovery in prostate cancer tissue from North
American patients, it was subsequently detected in individuals
with chronic fatigue syndrome (CFS) from the same continent.

However, most other research groups, mainly from Europe,
reported negative results.

The positive results could possibly be attributed to
contamination with mouse products in a number of cases, as
XMRV is nearly identical in nucleotide sequence to endogenous
retroviruses in the mouse genome.

But the detection of integrated XMRV proviruses in prostate
cancer tissue proves it to be a genuine virus that replicates in
human cells, leaving the question: how did XMRV enter the
human population?

We will discuss two possible routes: either via direct virus
transmission from mouse to human, as repeatedly seen for
e.g. hantaviruses, or via the use of mouse-related products by
humans, including vaccines.
We hypothesize that mouse cells or human cell lines used for
vaccine production could have been contaminated with a
replicating variant of the XMRV precursors encoded by the
mouse genome.





Introduction


The xenotropic murine leukemia virus-related virus (XMRV) is
undoubtedly the most controversial human virus since its first
detection in human samples in 2006 [1].

XMRV infection still lacks a firm disease association, although
the virus was originally isolated from prostate cancer tissue
and subsequently detected in the blood of American patients
with chronic fatigue syndrome (CFS) [2], and in the respiratory
tract of patients with or without a respiratory tract infection
[3].

However, irregular XMRV detection [2-7] suggests that it is not
likely to be a major causal factor. First, we do not know
whether the biological reservoir has been investigated thus
far, as most studies focused exclusively on blood or prostate
tissue (summarized in Table 1).

Second, some pathogenic retroviruses do not cause much of a
viraemia, and experimental infection of macaques suggests
that this is also the case for XMRV [8].

In these monkeys, virus inoculation resulted in a low transient
plasma viraemia, followed by a wide dissemination of
replicating virus into various organs including spleen, lymph
nodes and gastrointestinal tract.

Third, sequence variation may exist, but such variant virus
strains could be missed by the PCR primers used.



Whether or not the virus causes disease in humans (reviewed
extensively by Silverman et al. [9], see also comments by
Coffin and Stoye [10], by Kearney and Maldarelli [11], by
Kaiser [12], and the cautionary note by Weiss [13]), and how
and when XMRV entered the human population - as the first
gammaretrovirus to do so - remains unclear.

To add to the ongoing discussion, we would like to propose an
alternative possible source for XMRV, human vaccines or other
biological products that were produced in murine cells.



How did XMRV enter the human population? One of the most
striking aspects of XMRV biology is the high sequence
similarity to mouse chromosal sequences that encode
endogenous retroviruses.

Initially, this raised the speculation that contamination with
mouse DNA could explain the presence of XMRV in human
samples.

However, the absence of other mouse-derived sequences,
combined with the ease of infection of human cells with XMRV
in vitro [14], and the detection of integrated proviruses in
prostate cancer tissues [15,16] indicated that laboratory
contamination with mouse products is not a likely explanation
for the origin of XMRV, at least for some of these studies.

If contamination does not provide an explanation, where does
the virus come from and how did it end up in humans?



Direct transmission of viruses from wild rodents to humans is
not uncommon, e.g. rodent hantaviruses and arenaviruses
spread through excrement via aerosols and are able to infect
nonrodent species, including humans [17-19].

Transmission of xenotropic murine leukemia viruses (XMLV’s)
to humans is possible as human cells do express the XPR1
protein that is able to function as receptor for xenotropic and
polytropic murine retroviruses.

The human XPR1 receptor protein shows a preference for
xenotropic retroviruses, but is also able to mediate infection of
polytropic murine leukemia retroviruses (P-MLV’s) [20].

Classical laboratory mice strains are hybrids between Mus
musculus musculus, M. m. domesticus and M. m. castaneus,
with around two-thirds of the genome coming from M. m.
domesticus [21].
X-MLV’s cannot (re-)infect most of the laboratory mouse
strains due to polymorphisms in the XPR1 protein that disable
xenotropic virus entry [22].

Interestingly, the XPR1 genotype that prohibits X-MLV entry
was not found in wild-caught M. m. domesticus, suggesting
that it is a rare allele [23]. Indeed, extensive screening
identified 7 strains of laboratory mice strains containing a
permissive allele, of which at least three were susceptible to
XMLV and XMRV in cell culture [23].

In addition, the F/St mouse strain also produced infectious
XMLV together with a lifelong viraemia [23]. Many feral mice
species, e.g. M. dunni and M. spretus, are also susceptible to
infection with X-MLV’s [20,22,24].

Evidence on M. m. castaneus is conflicting, with some
reporting a non-functional and others a susceptible XPR1
phenotype [22,25]. The ability of XPR1 to function as a
receptor for xenotropic viruses was found to depend on the
identity of two amino acid residues [22].





The origin of XMRV?

Every mouse genome contains multiple copies of endogenous
MLV and has thus the capacity to express viral RNA and
possibly viral particles.

Endogenous MLV transcription has been described for many
tissues and several mouse strains. It remains unclear if and
when virus particles are generated and whether these particles
are actually excreted.

Zoonotic transmission of these viruses could have occurred in
the many million years that mice and men have shared the
same environment.

But current XMRV sequences isolated from human samples do
closely mimic mouse genomic sequences, thus suggesting a
low number of replication cycles since zoonotic transmission,
which is thus likely to have occurred recently.

The mutation rate of MLV’s is not different from other
retroviruses [26] (although its replication rate may be low),
implying that if the transmission had taken place a long time
ago, more nucleotide substitutions should have become fixed.

Phylogenetic sequence analysis, however, revealed very short
branches for XMRV and the mouse xMERV sequences on
chromosomes 7 and 9, indicating that very few mutations have
occurred since transmission [1,3,4].

In addition to the loci on chromosomes 7 and 9, a BLAST
search using the NCBI sequence database
(http://blast.ncbi.nlm.nih.gov/Blast.cgi) retrieves loci on
mouse chromosomes 4, 11 and 12 with a much higher
(98-100%) sequence identity to XMRV-gag nucleotide
sequences (e.g. GenBank accession numbers AC124739,
AY349138, and AL627314).

Blasting whole genome XMRV sequences recovers very similar
sequences with large stretches of sequence identity on mouse
chromosomes 4, 5, 13 and Y, especially for the 3’ end of the
XMRV genome.

These results suggest that the genome of human XMRV is
present, albeit in two parts, in the mouse genome with
effectively no nucleotide changes. Even in slowly evolving
retroviruses like foamy viruses, 100% sequence identity is only
seen in animals with close contact or humans that have been
bitten by an infected primate, suggestive of direct
transmission, while intraspecies variation is generally around
85-95% for the pol gene [27-29].


A recently described locus [23] on chromosome 1 of M.
musculus (GenBank accession number AC115959) contains a
provirus that is 92% homologous to XMRV from the 22Rv1 cell
line (GenBank accession number FN692043) over its complete
genome length. This provirus, Bxv1, is mainly found in
Japanese M. molossinus (a natural hybrid of M. castaneus and
M. musculus) and is highly expressed in some laboratory
mouse strains [23].

However, the Bxv1 provirus is less likely to be the source of
XMRV, as its similarity to XMRV is much lower than that of
other murine loci.





XMRV is a novel recombinant retrovirus

XMRV is actually a recombinant virus, resembling
polytropic-endogenous sequences for the 5’ half up to
approximately the middle of the pol gene and
xenotropic-endogenous sequences for the 3’ half of the
genome, which includes the env gene (see: [30]).

This recombination event is likely to have occurred in the
mouse before transmission to humans. At least one
recombinant provirus, Bxv1, is already found in the M.
musculus genome [23]. This locus is heterogeneous in
subspecies of M. musculus, suggesting that it represents a
recent integration.

Recombination rates are high for all retroviruses because they
package two copies of the RNA genome in virions, which drives
subsequent mixing of sequences during the reverse
transcription process.

Recombination also enables the generation of
replication-competent viruses from defective endogenous
proviruses. Recombination can also extend the viral host range
(cell type and/or host species).

A virus carrying a xenotropic env-gene is more infectious for
human cells as the human XPR1 protein has a preference for
xenotropic murine envelope proteins over polytropic ones.

The replication-competent endogenous cat retrovirus RD-114 is
an example of a recombinant virus expressed from endogenous
sequences. It combines FcEV gag-pol genes (FcEV is an
endogenous retrovirus of cats) and a BaEV env-gene (BaEV is
an endogenous retrovirus of African monkeys) [31].

RD-114 is expressed by all species of the genus Felis, but not
in other felines, and probably originates from a cross-species
transmission of BaEV, followed by a recombination event and
subsequent germ-line integration.





Are mouse-derived biological products the source
of XMRV?

Detection rates of XMRV in populations are extremely variable,
with 0-67% positivity in patients and 0-3.7% in healthy
controls [2-7], suggesting that virus prevalence and thus
exposure could vary significantly with geographic location.

Although the virus could possibly be transmitted from feral
mice to humans in a natural setting, followed by a rapid
dissemination in the human population, the high XMRV
sequence similarity on two continents would suggest an
alternative transmission route.

Likely sources of XMRV are mouse-derived products. Some
mouse genomes encode complete copies of X-MLV’s with at
least 92% similarity to XMRV; segments with even higher
homology are present on other locations, and could result in
novel recombinant viruses.

So, X-MLV’s that closely resemble XMRV could then be
produced from these loci and virions could be excreted from
mouse tissue or cell cultures.




Are X-MLV’s produced in mice?

MLV’s, including xenotropic sequences, are actively transcribed
in mouse brain [32], and mice can produce virus particles of
different MLV classes [33]. In vivo recombination between
endogenous and exogenous polytropic MLV’s has also been
reported, resulting in viable viral offspring capable of infecting
a variety of species [34].

The Bxv1 locus in M. musculus molossinus is an example of an
endogenous xenotropic/polytropic recombinant MLV that is
expressed and gives rise to a life-long viraemia in laboratory
mice of the F/St strain [23].


Although there was no evidence of X-MLV transmission to
human embryonic stem cells expressing XPR1 after
cocultivation with murine cells expressing X-MLV particles in a
single report [35], this does not imply that transmission may
not have occurred on another occasion.

The prostate carcinoma cell line 22Rv1 is a popular research
tool because it contains approximately 10 integrated copies of
the XMRV provirus and it produces infectious virus [36].

The origin of the 22Rv1 cell line may represent a recent
transmission case as a carcinoma was grafted in nude mice to
establish this permanent cell line [37]. The complete 22Rv1
provirus has 99% sequence similarity with other XMRV isolates
[38].

Possibly, the 22Rv1 carcinoma cells were infected with XMRV
by mouse cells surrounding the tumour graft [36].




Vaccines, viruses and contamination


One of the most widely distributed biological products that
frequently involved mice or mouse tissue, at least up to recent
years, are vaccines, especially vaccines against viruses.

Some, for instance vaccines against rabies virus [39], yellow
fever (YF) virus [40], and Japanese encephalitis (JE) virus [41],
consisted of viruses that were cultured on mouse brains.

Such vaccines were in use from 1931 (YF vaccine) until now
(Japanese encephalitis vaccine, licensed in Japan since 1954).

For rabies virus, early vaccines were mainly of goat or sheep
nerve tissue origin. In addition, suckling mouse brain-derived
rabies virus vaccines were used in South America and France
[39].

No mouse-derived rabies vaccine was ever licensed in the USA
[42]. Live-attenuated YF vaccines were originally also grown
on mouse brain, but an YF vaccine grown on chicken eggs
(named 17D) became available in 1937, and was since the
vaccine of choice in the America’s.

In 1962, contamination of the 17D vaccine with oncogenic
avian leukosis virus was detected both in England and in the
USA, but fortunately no excess of cancer incidence among
vaccinees was reported [40]. In France, the mouse-brain
derived YF vaccine was discontinued as late as 1982.


Although being the most effective means to prevent infectious
diseases and to safe lives, serious contamination problems
involving vaccines have occurred [43].

Contamination with unrelated viruses such as the presence of
hepatitis B virus (HBV) in yellow fever vaccine preparations
stemming from the use of human serum for stabilization, and
simian virus 40 (SV40) and foamy viruses through the use of
monkey cell cultures [43].

Some vaccine viruses are inactivated before use, hopefully
also inactivating any contaminating virus particles, but the
contaminating virus may be more stable than the vaccine
virus.

For instance, SV40 is highly resistant to inactivation [44].

Endogenous retroviruses constitute a distinct class of
contaminating viruses, as these viruses are encoded by all
cells of a certain species, and therefore cannot be avoided
even through rigorous screening [45].

Contamination with endogenous avian leukosis viruses is a
major problem for vaccine viruses grown in chicken embryos or
chicken embryonic fibroblasts [46]. Infectious cat endogenous
RD-114 virus has been found in several veterinary vaccines
produced in cat cell cultures [47,48].





XMRV and monoclonal antibodies.

Apart from vaccines, other mouse-derived biologicals could
have been a source of XMRV in the human population.

Monoclonal antibodies present a modern treatment for many
cancers and other diseases including cardiovascular disease,
psoriasis and auto-immune disorders (for a review see: [49]).

The first monoclonal antibody, OKT3 (to be used against
transplant rejection), was approved by the FDA in 1986.

The market for monoclonal antibody therapy has been
expanding rapidly after the year 2000. Initially, murine
antibodies produced by the hybridoma technique were used
[50], but these have been largely abandoned because of
(sometimes severe) allergic reactions.

The murine antibodies were often replaced by humanised
antibodies mainly produced in transgenic mice. Monoclonal
antibodies generated in mice could possibly be polluted by
XMRV and related viruses.

Platinum Taq polymerase from Invitrogen Corporation,
prepared using mouse monoclonal antibodies, is known to be
frequently contaminated with mouse DNA, which can generate
falsepositive PCR amplifications in combination with X-MLV or
XMRV primers [51].

It is less likely that monoclonal antibodies from mice are a
major source of XMRV in the human population as they are in
use only recently, but they could provide a future supply of
mouse-derived viruses.

Although monoclonals are treated with detergents before use
in patients, virus inactivation may not be complete, especially
as protein function should be conserved. And if retroviral
particles containing RNA genomes are copurified with the
antibody proteins, the absence of mouse DNA may give a false
impression of safety.





XMRV contamination of cell lines?

It is possible that XMRV particles were present in virus stocks
cultured in mice or mouse cells for vaccine production, and
that the virus was transferred to the human population by
vaccination.

The sequence homogeneity of all XMRV isolates known today
suggests that only a single or very few transmissions have
occurred, which is consistent with the proposed vaccination
route.

Nowadays, vaccine batches are carefully checked with
sensitive PCR assays for the presence of contaminating
retroviruses, but this screening was not performed in the early
years of vaccination ([52] see also [48]).

Apart from vaccines, other biological products have been
generated using mice or mouse cells. Alternatively, laboratory
contamination with a mouse-derived virus of cell lines used for
e.g. vaccine production could have occurred [53-55]. The virus
could then unintentionally have been transmitted to the
human population.

Nowadays, many vaccine strains are grown in human diploid
cell lines [56], which are susceptible to MLV infection. A recent
report detected other MLV-related sequences in CFS patients
and healthy controls from North America [57], suggesting that
more MLV strains may have been transmitted to the human
population, possibly in a similar fashion.

However, solid evidence that these polytropic MLV sequences
represent replicating virus is currently lacking.




Where was XMRV transmitted?

XMRV was found in samples from CFS patients in North
America, but not in Europe. The virus was detected in prostate
cancer tissue from patients on both continents. There is a
single report with negative results from China [58], and a
single report with one positive sample from Mexico [59] but
none from other areas of the world, leaving many questions
about the true distribution of XMRV in humans.

Prevalence of XMRV from North American studies varies
between 3.7-67% in four studies with two other studies
reporting negative results (one in CFS patients and healthy
controls [6], and one in HIV-infected patients receiving
antiretroviral therapy and untreated men at risk for HIV
infection [60]).

In Europe, XMRV was detected in two studies from Germany
[3], and in one from The Netherlands [61], but not in the
United Kingdom [5,62], France [63], Denmark [64], and two
other studies from The Netherlands [7,65], although the
nature of the samples analysed differed between studies.
Table 1 summarizes the results from these studies.




XMRV sequences from Germany and North America exhibit very
little nucleotide divergence, suggesting that they descended
from a common ancestor relatively recently.

A close inspection of the phylogenetic trees obtained with
XMRV-gag sequences [3,4] suggests that XMRV sequences
from the USA are closer to the common ancestor than German
XMRV sequences, although the trees are not optimal due to
the high sequence conservation.

Being closer to the most recent common ancestor (MRCA) is
suggestive of an older virus. Possibly, XMRV was transmitted
from mice to men in the USA, and soon after this event
introduced into Germany.

Germany had close connections with the USA after World War
II, with large numbers of military personnel (and their
families) stationed in Germany from 1945 till present times.

In 2006, there were still 57.080 American army employees
distributed over more than 200 locations in Germany, mainly in
the south and west of the country
(www.defense.gov/pubs/BSR_2007_Baseline.pdf).

US military personnel are highly vaccinated, e.g. virtually all
recruits were vaccinated with YF vaccine in 1941- 1942 after
the outbreak of World War II [40].

A massive outbreak of jaundice, with at least 26,000 cases in
the Western region of the USA, was due to the use of human
serum contaminated with HBV in the vaccine (see [40]).

Recently, massive smallpox vaccination of the US army
personnel has been carried out [66]. XMRV infected Americans
could subsequently have introduced the virus into Germany.




Spread of XMRV

The combined results suggest (1) that XMRV was recently
transmitted from mice to humans, either from a single source,
or at least from a single (sub) species of mice, and (2) that all
XMRV-positive individuals known today were infected with this
newly-emerged virus only recently, as a very high sequence
identity is normally only seen after a direct retrovirus
transmission.

Whatever the mechanism of XMRV cross-species transmission
from mouse in humans, the possible spread from human to
human forms a major health threat.

Sexual transmission was initially proposed [67], but XMRV was
not detected in seminal plasma from HIV- infected men [65].

The detection of XMRV fragments in the respiratory tract [3]
suggests that the virus may be transmitted by saliva, although
RNA concentrations were low. Transmission through saliva,
mainly by biting, has been reported for most retrovirus genera,
including ecotropic MLV’s [68].

Another major threat is transmission through blood products
as infectious virus has been cultured from blood cells [2].


Up till now, all patients with detectable XMRV have been
adults, the majority of them middle-aged or older (mean ± 55
years).

A study in 142 children with a diversity of pathologies,
including respiratory diseases in France revealed no XMRV
infections in that age group [63], although the incidence of
XMRV in France is not known.

Another study in autistic children from the USA and Italy was
also negative for XMRV [69].

XMRV can likely be acquired at any age, and then probably
establishes a chronic, latent infection like other retroviruses.
Therefore the age of XMRV-infected individuals does not
provide an unambiguous clue about when XMRV entered the
human population.




Conclusion


In conclusion, the most likely mode of XMRV transmission
points to mouse-derived biological products, but it cannot
formally be excluded that the virus was once transferred from
feral mice to humans.

The latter scenario is less likely as it would imply that a very
rapid spread in the human population must have occurred to
explain its presence on two continents. In this scenario, the
extreme sequence similarity among XMRV genomes, both
between and within individuals, would argue that the virus
replicates at very low levels.

Among the biological products, vaccines that were produced in
mice or mouse cells are possible candidates that warrant
further inspection. If XMRV was introduced in the human
population through the use of biologicals, a background level
of the virus in the human population, possibly varying with
geography or age group, would be expected.

Such a low level presence would then also explain the
(absence of) detection of the virus in different studies, as
well as its controversial association with disease.



We hope that this hypothesis will spur further discussion and
help to resolve the many remaining XMRV questions.




Acknowledgement

We thank Hans Zaaijer for insightful discussions and
proofreading of the manuscript.




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