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Alter/Lo:

XMRV-achtige virus-varianten

aangetroffen bij

87% van de CVS-patiŽnten.

 

 

 

 


 

  

 

Gezien de tegenstrijdige bevindingen in studies en de kontroverse t.a.v. ME/CVS en XMRV

is de Alter-studie een belangrijke mijlpaal in de zoektocht naar de rol van XMRV bij ME/CVS.

 

De belangrijkste konstateringen van de "lang verwachte" FDA/NIH-studie,

die de XMRV-Lombardi/Mikovits-studie in belangrijke mate bevestigt, zijn:

  • Bij een groot deel van de onderzochte ME/CVS-patienten (86,5%) en bij een deel
  • van de gezonde bloeddonors (6,8%) werden XMRV-achtige virussen gevonden.

    Op basis van genetische variaties werden vier MLV-achtige virusvarianten onderkend

    die genetisch meer weg hebben van polytrope endogene muis-retrovirussen dan van XMRV.

    (polytroop: in staat om man en muis te infekteren, endogeen: genetisch overgedragen)

  • Het virus kan jarenlang persisteren, getuige het feit dat bij 7 van de 8 patiŽnten zowel
  • in een recent monster als in een 15 jaar oud monster  "het" MLV-virus aangetroffen werd.

  • Vervuiling (kontaminatie) van de bloedmonsters (hťt "tegenargument") lijkt uitgesloten,
  • gezien o.m. het feit dat het virus bij genoemde patiŽnt na 15 jaar al genetisch afwijkt,

    aanvullend onderzoek (semi-geneste PCR onderzoek naar mitochondriaal muis-DNA) ťn

    de genetische variaties van de MLV-achtige virussen bij diverse patiŽnten.

  • Of "het" virus de ziekte veroorzaakt/in stand houdt (oorzaak) of een gevolg is
  • (bijv. van een verzwakte afweer) zal de toekomst uit moeten wijzen.

  • Het feit dat "het" virus niet gevonden werd in studies die dit jaar verschenen
  • (van Kuppeveld et al., McClure/Wessely et al., Kerr/Gow)

    wordt mogelijk verklaard door het feit dat de gevoelige PCR-test niet geschikt is om genetische variaties van "het" virus op te sporen en/of verschillen in patiŽntenselektie.

 

 

 

 

Slotopmerking:

 

Het percentage geÔnfekteerden ligt mijns inziens (gezien de vergaarbakdiagnose "CVS") vrij hoog.

Dit wordt wellicht verklaard door het feit dat de patiŽnten niet aselektief gekozen zijn.

De meeste deelnemers waren mensen die voldeden aan de stringentere Holmes-kriteria,

waarvan vermoed werd dat ze mycoplasma-geinfekteerd waren.

 

De toekomst zal antwoord moeten geven op de vraag hoeveel patiŽnten geÔnfekteerd zijn,

alsmede op de vraag wat de rol en oorzaak is van de genetische variaties ťn

de oorzaak-of-gevolg-vraag (oorzaak ME/CVS of gevolg van een verzwakt afweersysteem).

 

 


 

Perskonferentie FDA:

 

 

Voor het transkriptie van de perskonferentie n.a.v. de publikatie, klik op onderstaande afbeelding:

 


 

 

Voor de vragen en antwoorden na de perskonferentie, klik op onderstaande afbeelding

 

 

 

Voor geluidsopnamen van de perskonferentie, klik op onderstaande afbeeldingen:

 

   
deel 1 deel 2

 

 


 

Felicitatie Annette Whittemore aan Alter en kollega's:

 

 

 

 

Reaktie Judy Mikovits op studie Alter, Lo en kollega's:

 

 

 

 

 


 

Vragen aan en antwoorden van ME/CVS-experts (CAA, CFIDS Association of America):

 

Enkele in het oog springende citaten:

 

 

Vraag:

 

Youíve been at this a long time and have seen evidence that associates several different infectious agents with CFS. What are your thoughts on this particular study?

 

Antwoord:

 

Based on my experience talking to the patients, and examining them, I think that the most likely explanation of their illness in most of the patients with CFS is that they are suffering from some kind of chronic infection. I think it is very plausible that the infection is of a type that cannot be fully cleared by the immune system, although that has not been proven. "I think it is very plausible that the key symptoms of CFS are caused by the immune systemís attack on the infectious agent(s) that may be involved, although that has not been proven. Finally, since symptoms are experienced in the brain, I think it is very plausible that the immune system molecules that may cause the symptoms are either produced in the brain (because the infection is there) or reach the brain through the circulation, although that has not been proven.

 

A.L. Komaroff, MD

 

 

 

Vraag:

 

There isnít any information included in the article about 12 patients whose samples were sent to Dr. Lo in the early 1990s. By which criteria were they diagnosed? Were there any particular clinical features about these patients that made them different from other patients you were seeing at the time or have since in the years since?

 

Antwoord:

 

I do not recall the particulars of such patients as that was almost 20 years ago. However, my clinic then saw only CFS and they are pretty much the same as what I see today from 26 states and 7 countries. I have a poster presentation at the International XMRV Workshop on September 7-8 regarding XMRV/MLV/HGRV detection in my practice done on 47 consecutive patients from October 2009 to December 2009. Those 47 patients are very well characterized including the percentage of overlap diagnoses (FM, MCS, Lyme, IBS, mold-illness), KPS, age, sex and geographic distribution. The data, I think, are extraordinary, but I cannot talk about it until after the 8th.

 

Paul R. Cheney, MD, PhD, The Cheney Clinic

 

 

 

Vraag:

 

As presented at the Cold Spring Harbor Laboratory (CSHL) conference on Retroviruses (May 2010) and reported in the Wall Street Journal's Health Blog, the Whittemore Peterson Institute (WPI) has found gag sequences that reflect greater variability amplified from the PBMCs from CFS patients than was originally reported for XMRV. Do the variants you have identified match the four MLV variants described in the PNAS paper, or do they represent even greater diversity within this family of gammaretroviruses?

 

 

Antwoord:

 

It is unfortunate that no matter how much data we presented and published (Mikovits et al., Virulence, July 30, 2010) suggesting more sequence variation as a valid scientific explanation for negative studies both in CFS and prostate cancer, our data were met not with critical evaluation but with unsupported allegations of contamination.

 

Judy A. Mikovits, PhD, Director of Research, Whittemore Peterson Institute

 

 

 

 

Voor alle vragen en antwoorden, klik op onderstaande afbeelding:

 

 

 

 

 


 

In de buitenlandse media:

 

 

   
   
   
   
   
   
   
   
 
   

 

 

 

In de Nederlandstalige media:

 

 

   
   
Noorderlicht
   
   
 

 

 

 

Kommentaren, achtergronden en toelichting:

 

 

   
   
   
   
   
   

 

 


 

Relevante citaten (uit kommentaren etc.):

 

 

M.b.t. de patiŽntenselektie:

 

 

Kimberly McCleary (CAA): Another turn of the retrovirus kaleidoscope.

http://www.cfids.org/mlv/caa-response-082310.asp

 

 

The CFS patients' samples tested in Lo's lab were obtained in the early 1990s from 42 patients seen in independent CFS-specialty clinics maintained by Anthony Komaroff (Brigham and Women's Hospital, Boston, Mass.), David Bell (private practice, Lyndonville, N.Y.) and Paul Cheney (private practice, Charlotte, N.C.) for a study of a type of bacteria called Mycoplasmafermentans. As reported in Clinical Infectious Diseases in 1993, the samples were all negative for Mycoplasma fermentans.5 The case definition cited in the 1993 paper is the Holmes definition,6 although the description of cases in the PNAS paper is specifically limited to the 25 patients drawn from Komaroff's clinic. All 25 of Komaroff's patients met the Holmes criteria for CFS and 21 of them also met the Fukuda criteria7 published in 1994. Unopened vials from 37 of these original 42 patients were stored by Lo and co-workers for the past 15 years.

 

After the paper linking CFS and XMRV was published in Science in October 2009, Lo's team at FDA tested these stored samples for the presence of MLV-related viral sequences including XMRV, using nested polymerase chain reaction (PCR). They recorded positive results in 32 of the 37 (86.5%) samples, although none of the sequences for MLV-related viruses matched those re≠ported by Lombardi et al. in Science. Three of 44 samples obtained between 2003 and 2006 from healthy blood donors living in the Washington, D.C. area also tested positive for MLV-related gag viral sequences; none of these positive results matched the strain of XMRV reported by Lombardi either.

 

This year, eight of the 25 patients recruited by Komaroff into the 1993 Mycoplasma study were recontacted and fresh blood samples were drawn and tested by Lo. Seven of these eight fresh samples again tested positive for MLV-like viral sequences. This extra step makes Lo et al. the first group to report on MLV-related viral sequences from serially followed individuals including freshly collected blood samples from CFS patients.

 

 

 

M.b.t. XMRV (Mikovits/Lombardi) en MLVs (Lo/Alter):

 

 

CFS Central: The FDA/NIH/Harvard "XMRV" study: The same thing, only different.

http://www.cfscentral.com/2010/08/fdanihharvard-xmrv-study-same-thing.html

 

 

Most surprising is that the PNAS study didn't find XMRV, which stands for Xenotropic Murine Leukemia Virus-Related Virus, in any patients or controls. Instead, the researchers ó from the National Institutes of Health (NIH), the FDA and Harvard Medical School ó detected novel close cousins to XMRV called MLVs ó which stands for Murine Leukemia Viruses ó in 86.5 percent of 37 patients and nearly 7 percent of 44 controls.

 

Alter explained to CFS Central in a telephone interview. "The fact that we didn't find XMRV doesn't bother me because we already knew that retroviruses tend to be variable. They mutate a lot, basically. This is true of HIV and HCV [hepatitis C virus]. It's not one virus. It's a family of viruses."

 

Dr. Judy Mikovits, principal investigator of the 2009 Science study, agrees. "We presented a paper at the Cold Spring Harbor RNA tumor virus meeting in May showing that patients reported in Lombardi [the Science paper] contained both [Alter's] X and P variants as well as at least one other family member," Mikovits told CFS Central.

 

 

Amy Dockser Marcus (Wall Street Journal):

Betting on X - As in XMRV - With a Big-Ticket Research Center.

http://blogs.wsj.com/health/2010/08/26/

betting-on-x-as-in-xmrv-with-a-big-ticket-research-center

 

 

The Health Blog asked Annette Whittemore after the Alter paper came out if she was concerned about how closely linked the institute is with X. She said that one of the hot topics at the recent WPI symposium was whether X might turn out to have different strains, the same way scientists now talk about HIV-1 and HIV-2. "We called it XMRV at the time because that was the name that had been used," she says. As scientists understand more about the broader family - including the P viruses mentioned by Alter Ė the terminology, too, might eventually change. "The name isn't as important as the concept that these are retroviruses infecting human beings," she says.

 

 

Cort Johnson (Phoenix Rising): Four viruses? The Alter XMRV paper arrives.

http://www.forums.aboutmecfs.org/content.php?213-Four-Viruses-The-Alter-XMRV-Paper-Arrives

 

 

The genetic sequences Lo and Alter looked for were the same as the genetic sequences that all the other studies looked for. The Lombardi (WPI), Groom, McClure and Switzer (CDC) papers all looked for 'gag' sequences identified by primer #'s 419F/1154R. (Dr. Racaniello noted that everyone had tried to duplicate the WPI's results by looking for the same sequence and they did.) The difference with the Alter group is that over half the people with ME/CFS tested positive on the first pass of the PCR and more tested positive on the second. They received similar results using their own in house primer set.

 

At this point the Lo/Alter group was right on the mark with the WPI - both had found that a high proportion of their CFS samples tested positive for that sequence. The gag sequence they identified, however, is not specific to XMRV - it is a marker for a range of murine leukemia retroviruses of which XMRV is one. Hence, both groups did a phylogenetic analysis to determine exactly what viruses they had identified; first they amplified the sequence in order to flesh it out, and then they compared it to other known retroviruses and here was where the two studies diverged.

 

The Alter/Lo group discovered they had not found XMRV at all; instead they had uncovered three of its close cousins (96.6% similarity). While XMRV lacks the genetic sequences it needs to infect mice, these retroviruses had them - instead of xenotropic MLV's they were polytropic MLV's able to infect mice and other mammals. (Tropism refers to the types of tissues or organisms a pathogen can infect). Although three MLV's were found one MLV dominated the rest, infecting 86% of the CFS patients. One of the MLV's was found also in one healthy control.

 

An accompanying commentary "Mouse Retroviruses and chronic fatigue syndrome: Does X (or P) mark the spot?" indicated the MLV's, of which XMRV is one, are a quite intermingled group. A major part of the XMRV genome, for instance, is simply a compilation of various MLV sequences. This kind of 'cross-dressing' or pseudotyping commonly occurs in the MLV's and is believed to play a key role in their ability to infect new species.

 

(The small sample size of the WPI's phylogenetic analysis- 3 samples - could have contributed to the low genetic variability reported).

 

 

 

M.b.t. kontaminatie (vervuiling van de monsters in het laboratorium):

 

 

CFS Central: The FDA/NIH/Harvard "XMRV" study: The same thing, only different.

http://www.cfscentral.com/2010/08/fdanihharvard-xmrv-study-same-thing.html

 

 

Important to note is the retroviruses detected in those seven patients in 2010 had mutated in the 15-year interim. "That's just what you'd expect from a retrovirus," said Alter. "That's more evidence that this is a real agent, not a sequence floating around in the lab."

 

 

 

M.b.t. het feit dat XMRV/MLV moeilijk in het bloed te vinden is:

 

 

CFS Central: The FDA/NIH/Harvard "XMRV" study: The same thing, only different.

http://www.cfscentral.com/2010/08/fdanihharvard-xmrv-study-same-thing.html

 

 

Emory University scientists who injected XMRV into macaques this past spring reported that even when the virus was undetectable in the blood, it thrived in the reproductive organs as well as the spleen, gut, bladder, lung, liver and lymph nodes. Explained Alter, "When viruses are in low titer, sometimes you can find them one day and not find them another day."

 

 

 

M.b.t. de vraag waarom andere studies geen XMRV/MLVs konden vinden:

 

 

Cort Johnson (Phoenix Rising): Four viruses? The Alter XMRV paper arrives.

http://www.forums.aboutmecfs.org/content.php?213-Four-Viruses-The-Alter-XMRV-Paper-Arrives

 

 

An FDA FAQ paper just released specifically addressed the disparity between the CDC and FDA/NIH studies results. It strongly suggested that different study populations not differences in methods were the key difference between the studies. It indicated, in something of a shocker, that the Alter/Lo group tested 34 CDC samples and found XMRV in none of them. Furthermore, both labs were equally able to detect XMRV in known positive samples provided by the DHHS Blood Working Group.

 

This strongly indicates that patient selection is a key factor in the disparate results at least in these two groups and indeed, the two groups were very different. The Alter study participants were provided by Dr. Komaroff from patients at his clinic. (Interestingly only half of them met the Fukuda criteria while all met the Holmes criteria. The CDC study patients were picked up by random sampling and somewhere around half of them had never seen a physician for their illness. (Dr. Komaroff noted that some of the patients in the 'other' studies were not the kind of patients that came by his door). Some of the CDC samples also came from people meeting the Empirical definition which increased prevalence rates dramatically and ushered in a new breed of 'CFS' patient.

 

 

 

 


 

 

 

Detection of MLV-related virus gene sequences in blood of

patients with chronic fatigue syndrome and healthy blood donors.

PNAS. Published ahead of print August 23, 2010. doi:10.1073/pnas.1006901107.

Shyh-Ching Lo, Natalia Pripuzova, Bingjie Li, Anthony L. Komaroff, Guo-Chiuan Hung, Richard Wang, and and Harvey J. Alter.

 

 

 

Chronic fatigue syndrome (CFS) is a serious systemic illness

of unknown cause.

 

A recent study identified

DNA from a xenotropic murine leukemia virus-related virus (XMRV)

in peripheral blood mononuclear cells (PBMCs)

from 68 of 101 patients (67%)

by nested PCR,

as compared with 8 of 218 (3.7%) healthy controls.

 

However,

four subsequent reports failed to detect

any murine leukemia virus (MLV)-related virus gene sequences

in blood of CFS patients.

 

We examined

41 PBMC-derived DNA samples from 37 patients

meeting accepted diagnostic criteria for CFS and found

MLV-like virus gag gene sequences in 32 of 37 (86.5%)

compared with only 3 of 44 (6.8%) healthy volunteer blood donors.

 

No evidence of mouse DNA contamination

was detected

in the PCR assay system or the clinical samples.

 

Seven of 8 gag-positive patients

tested again positive

in a sample

obtained nearly 15 y later.

 

In contrast to the reported findings of

near-genetic identity of all XMRVs,

we identified

a genetically diverse group of MLV-related viruses.

 

The gag and env sequences from CFS patients

were more closely related to

those of polytropic mouse endogenous retroviruses

than to

those of XMRVs and were even less closely related those of ecotropic MLVs.

 

Further studies are needed

to determine whether

the same strong association

with MLV-related viruses

is found

in other groups of patients with CFS,

whether

these viruses play

a causative role in the development of CFS, and

whether

they represent

a threat to the blood supply.

 

 

 

Keywords:

 

xenotropic murine leukemia virus-related virus

murine leukemia virus-like virus

viral gag gene sequence

polytropic

mouse mitochondria DNA PCR

 

 

 

 

Volledige tekst studierepport:

http://www.pnas.org/content/early/2010/08/16/1006901107.full.pdf

 

 

Aanvullende informatie:

http://www.pnas.org/content/suppl/2010/08/16/1006901107.DCSupplemental/

pnas.201006901SI.pdf.

 

 


 

Kommentaar:

 

Mouse retroviruses and chronic fatigue syndrome: Does X (or P) mark the spot?

PNAS. Published online before print August 23, 2010. doi: 10.1073/pnas.1007944107.

Valerie Courgnaud, Jean-Luc Battini, Marc Sitbon, and Andrew L. Mason.

 

 

http://www.pnas.org/content/early/2010/08/16/1007944107.full.pdf

 

 


 

Met dank aan Jeroen, Erik, Rubia en talloze anderen.