Friday, November 18, 2011
so let's get this straight; CFS patients don't have XMRV or MLVs, but if they did, it would explain the neuromuscular pathology....
Dusty Miller, greatly respected in the retroviral community, has just published a paper in the Journal of Virology describing how, if it really existed in humans, XMRV could induce apoptosis of human neuroblastoma cells - presenting a potential mechanism for the neuromuscular pathology seen in patients with chronic fatigue syndrome. I don't normally blog about XMRV or other MLVs that might be capable of infecting humans - but we did just publish a paper showing how easy it would be to get false-negative results when attempting to PCR amplify the GAG region of viruses like these, which would be especially relevant if the titer or copy number of the virus in various tissues was low. While several journals considered this scientifically worthy work, they all thought the "interest" in this paper would be low. By publishing in an open access journal, we've now had 850 accesses to our paper in 3 weeks - suggesting at least some people are in fact interested in it. I then wonder if anyone actually did find polytropic/xenotropic MLVs in human disease, would they be able to publish it? Would it not get held back by virtue of the already published negative data, which in most cases was poorly controlled for or maybe not the appropriate source of tissue? Just a thought. It just seems highly coincidental that the virus (family) that apparently is so ubiquitous in the lab - from reported contamination in heparin blood tubes to DNA extraction kits...can in some cases infect human cells...and can reproduce the symptoms seen in CFS patients, whom at one point were thought to carry the virus. Its just a thought...you can read the paper, an epub, here - Xpr1 is an Atypical G-protein Coupled Receptor that Mediates Xenotropic and Polytropic Murine Retrovirus Neurotoxicity
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Thx Dr Dr. O'Keefe. http://niceguidelines.blogspot.com/2011/11/so-lets-get-this-straight-cfs-patients.html
ReplyDeleteThanks for sharing your thought! I hope you will keep thinking about this.
ReplyDeleteThank you for making this very important point.
ReplyDeleteHi Dr. O'Keefe,
ReplyDeleteThanks for commenting on our paper. It was perplexing and frustrating for me, as we were doing this work, to see these sort of neurtoxic effects yet at the same time see the association between XMRV and CFS become so riddled with holes. I think the case for XMRV detection due to contamination with plasmid / 22Rv1 / 3T3 cells is extremely difficult to dismiss, however. Unless presented with evidence otherwise, I think the XMRV / CFS assocation is pretty much non-existant. Still, our work demonstrates a mechanism for how MLVs cause neuropathology in mice, and we believe these findings may ultimately translate into human neurologic disease as well.
I'm just waiting for someone to explain how I ended up with antibodies to a lab contaminant ... Apparently it is a response to a different but close pathogen - okay. Anybody interested in what?
ReplyDeleteI have been in numerous studies - Dr. Dharam Ablashi, who is the co-discoverer of HHV-6 and it's two variants, found me positive for HHV-6A in 1998. Also, EBV was reactivated for the fourth documented time. Years later, after doing well on a Phase III immune modulator that FDA took away in Feb 2008, I relapsed again badly. In 2008 and 2009 I would be found positive for EBV, HHV-6, HHV-7, CMV, and Coxsackie B. A lumbar puncture in July 2009 to rule out MS found active cases of HHV-6 and CMV in my spinal fluid. Maybe there is a relationship to whatever was giving me antibodies to a lab contaminant.
When beset by these viruses, I have symptoms of encephalitis and significant CNS dysfunction.
So thank you for some healthy intellectual,curiosity. As a former scholar in a different field, I wish there was more in medicine.
Finally a voice of reason. There are many unanswered questions about these types of viruses that need studying. Thanks for bringing this up.
ReplyDelete"………presenting a potential mechanism for the neuromuscular pathology seen in patients with chronic fatigue syndrome.>
ReplyDelete>………and can reproduce the symptoms seen in CFS patients……...."
Your ‘thought’ is apparently constructed on the translation of “ potential” into “can” without any supporting evidence; one might expect the worthiness of the ‘thought’ to end there.
M.E/CFS is a condition described by multiple symptoms only, none of which need (under current understanding) have common causation in any one individual, let alone be common across a global patient population estimated to exceed 10 million. There was always a huge question about the WPI work because they were reporting such high levels of XMRV presence from a diverse population without any explanation of how communicability of XMRV was achieved. Later reports from Mikovits of 80%+ ‘infection’ levels stretched credibility to breaking point. All though certain patient groups refuse to accept the phylogeny work of Paprotka et al, there has been no published refutation of Paprotka’s phylogeny, and it is this more than anything else, that has given an end point to publisher interest in XMRV as a human disease. Even if XMRV is capable of causing disease in humans (a very remote possibility given the many established limitations) XMRV can not be the sole or even defining cause of M.E/CFS if XMRV is an anthropogenic creation little more than 20 years old. Miller et al have identified possible mammalian disease causing processes that might offer a line of research that might in turn explain some M.E/CFS symptomology. But any study of M.E/CFS that claims to demonstrate a single causative process across a highly diverse population should raise especial scepticism on probabilistic grounds alone, and after Lombardi et al fiasco, journals are unlikely to welcome M.E/CFS related research papers which are not expressly parsimonious in their scope and reference.
Finally ‘read’ numbers on an open access publication that deals with a hot button issue are hardly recommendations of validity, one can safely assume that of “850 accesses” the vast majority came from links clicked on a few activist web sites.
To add to earlier posting, I find the following statement rather curious:
ReplyDelete"It just seems highly coincidental that the virus (family) that apparently is so ubiquitous in the lab - from reported contamination in heparin blood tubes to DNA extraction kits...can in some cases infect human cells [...]"
This does not seem "highly coincidental" to me, but exactly what you would expect from a virus that was generated by recombination of two mice viruses during human tissue passaging. The result of any recombination event that "survived" its "human" enviroment, would be expected to be able to infect some human cells.
Suppose that tomorrow all laboratories would be starting to passage elephant tissues through lab tigers. When (eventually) a tiger virus was generated (through random mutations or a recombination event) that would be able to "survive" its new environment (elephant tissue), it would be perfectly normal for this new tiger-like virus to also be able to infect (some) elephant cells in real life.
The viruses discovered by Dr Mikovits and Dr Ruscetti have been proven to not be VP62/XMRV. The isolates now need to be fully sequenced. So far the gag sequences are the same as those found by Lo et al. polytropic gag sequences. Every single negative paper has failed to clinically validate their assays and has instead optimised to a free floating virus, that has never been found in nature and cannot be said to be the viruses discovered in Lombardi et al.
ReplyDeleteThere is no reason to believe 22Rv1 as a source of contamination for several reasons.
1. 22Rv1 has never been in the WPI or NCI labs.
2.. 293T cells are also infected with XMRV are predate the 22rv1 cells. They are taken from a patients in1977.
3. The assays used in Paprotka et al. were only ever shown capable of detecting a whopping 2000 copies per 100 cells of VP62/XMRV and the one used to screen the early xenografts failed to detect XMRV/VP62 in 293T cells.
4. There is a third assay used in the paper, as named by Pathak at a conference, that is omitted from the paper!!! An reverse transcriptase PCR assay. This was only used on the later xenografts.
5. PreXMRV has not been shown to exist as it was constructed from 3 separate sources.
It looks like 22Rv1 is only contaminated with VP62, which the WPI/NCI samples have been proven free of!
Dale
5. is preXMRV-1
ReplyDeleteDale
It is time someone did a tissue study on ME patients, preferably Lymphoid tissue, using the assays from Lombardi et al. What good are studies that using assays not clinically validated.
ReplyDeleteDale
In Vito infidellium - I think you are displaying some circular logic here. The reason some people claim ME/CFS is due to multiple causes is precisely because nobody was trying to tie the diverse symptoms together and find a single cause. If you pay close attention to the symptoms and history of this illness you'd realize that the onset, history, and symptoms of patients have more features in common than they are different. This going back much more than 20 years in reported outbreaks... Given this pattern, it's much more likely that there is a single etiology than not.
ReplyDelete@ Anon 19/2011/ 10.25am
ReplyDeleteAt no point did I invoke circularity. There are simply too few definitive reference points in the symptomolgy of M.E/CFS for there to be a high probability of a single causative agency of disease across the affected population. Certainly an ‘outbreak’ hypothesis is worthy of testing but to date there is only limited correlatative data that might in turn imply single infection events, but even then these could only apply to a tiny number of those diagnosed globally with M.E/CFS by symptomology. There was a fundamental failure in the conception of Lombardi et al study: the researchers (and ultimately the peer reviewers) failed to consider the foundational hypothesis of the study in terms of prior plausibility. And a plausibilty test in M.E/CFS research requires that a single causation across the global population be considered to be highly implausible. Had Lombardi et al limited their study to an ‘outbreak’ population, then a test of prior plausibility would have been satisfied, but the wide geographical sourcing of samples made any ‘outbreak’ criteria irrelevant. What has followed in the WPI/XMRV debacle has been pure post hoc ergo propter hoc as XMRV has been repeatedly ‘fitted out’ as the agency of M.E/CFS without even the slightest attempt to match epidemiology to the imputed cause.
There is no need to believe a pathogen can only be involved in outbreaks. By testing 25 patients from an outbreak and others from around the world, a better grasp of how the virus could be contributing to disease was provided.
ReplyDeleteIn vitro, why would it be any more implausible that there is a single cause of CFS than any other illness in which a group of patients share common symptoms, history, and onset? Frankly, I'd think it's actually most logical to test this hypothesis first before you go assuming there is something more complicated (multiple causes for the same illness) is going on.
ReplyDeleteIn response to Andy's comment above, well said - I agree with you with regards to XMRV and the plasmid contamination problem. However your findings have the potential to apply to related MLVs. I am not entirely convinced that polytropic or other MLVs aren't infecting humans. I think that the same level of healthy (usually) skeptism regarding positive findings of these viruses should have been extended to the negative finding papers, as well. I do not believe that it has; ill-defined levels of detection and poorly described methods attest to this. As I mentioned in my post, we found that it was unbelievably easy to generate false-negative results using PCR detection - we accidentally found this while testing our levels of detection for mouse DNA contamination in patient samples. I think the best remedy for this is to include an internal control in every patient sample tube; the control would need to be almost identical to the intended target but ideally, a little larger (we'd take a plasmid containing the targeted region and clone in a 30 base pair piece of DNA in the middle). This would be spiked into patient samples at the level of detection of the assay. Therefore if inhibitors are present in the sample, the internal control will not amplify and the test is inconclusive. The reason for having the internal control a little larger is so it can be distinguished from a true positive when run on a gel or otherwise analyzed. If you are looking for MLV-type sequences, the sample would be spiked with a "gag" like sequence (or whichever bit is the target), and a replicate sample should be tested for mouse DNA contamination, also spiked with an internal positive control for mouse DNA (i.e. mouse mitochondrial DNA target). To my knowledge none of the published papers have used these type of controls, instead using a single tube with VP62 plasmid as a control for the entire PCR reaction. The problem with that is vanishingly small amounts of plasmid have very high copy numbers of the target, in this case XMRV/MLVs (many sets of primers against XMRV will also amplify other MLVs). Almost all the papers we looked at did not specify how much of the positive control they used; but let's just say they used one microliter of a typical plasmid prep - so 50ng of plasmid...diluted it 1:1000, so now its 0.05 nanograms of plasmid...guess how many copies you have? For VP62 that would be about 6 million. If the test sample has significantly less copies, or differences at the primer binding sites, it might not be detected. In addition, as we demonstrated in our paper, accidental carry-over contamination - for example for touching a lab book that has contacted your gloved hand that loaded a previous PCR on a gel (we are talking less than millionths of a liter) - from a negative control or PCR reaction - is sufficient to completely block legitimate amplification of 2 million copies of an MLV GAG sequence. Until I see those kinds of controls, I would suggest that inability to find a virus in a sample is not the equivalent of evidence against the existence of said virus.
ReplyDeleteNo study has found VP62 in nature and it is not the viruses discovered in ME. It is well known that gamma retroviruses exist at a low titre in the blood and that these viruses have a preference for integrating into CpG islands. So although controls are important do you intend on optimising to a clinical positive or will you introduce another variable by using an assay with unknown ability to detect HGRVs? Why not replicate the methodology used in Lombardi et al?
ReplyDeleteThe people who report no evidence of murine related retroviruses have all optimised their PCR assays to be able to detect the vp62 strain of xmrv using the assertion that murine related human retroviruses can only exist as one invariable sequence.In other words they have merely demonstrated the analytical sensitivity of their assays.They have used high stringency annealing temperatures so that their assays could only detect the vp-62 sequence
ReplyDeleteThey have not demonstrated the clinical or diagnostic sensitivity of their assays.There is considerable evidence that MLV viruses rapidly establish latency.The vp-62 strain of XMRV has displayed a greater affinity for G-C rich promoter regions of genes even than those MLV, examined
The two major reasons for PCR failure are low copy number and secondary structures in the nucleic acid containing the target sequence
There are a number of variables that determine the yield of a PCR reaction,
It is likely that an assay optimised to detect free proviral DNA in a spiked sample would face a different challenge when faced with a MRV at low copy number and integrated into gene promoter regions
It is probable that the assay would need to be reoptimised in order to be able to do so.Ajusting the annealing temperatures and magnesium concentrations are the most commonly used methods of reoptimising a PCR assay. This step has been conspicious by its absence in all the studies where the authors have claimed the absence of MRVs in study populations examined
In Lombardi et all they designed their nested reverse transcriptase PCR assay based on the assay developed by urisman et all.This assay was optimised untill it was able to detect GAG sequences in the cDNA of patients who had been found to be infected using IHC FISH and a microarray technique.The difference in the lombardi assay is they lowered the annealing temperatures and adjusted the magnesium concentrations to increase the sensitivity of the assay. This means that the assays were not restricted to detecting one single sequence but also closely related sequences
This was indeed wise as it is now known that the viruses detected were not related to the vp-62 strain of XMRV in any way
This further explains the findings of the negative studies using high stringency conditions capable to detecting the vp-62 sequence only
There are other reasons which explain the negative findings which I hope to post later.
Thankyou for being given the opportunity for making these posts on your blog
I have just read some of the comments above which commented that no single initiating event could produce all the symptoms of a neuroimmune disease
ReplyDeleteThat is actually not true activated microglia with the resulting oxidative stress,proinflammatory cytokine production and mitochondrial damage could account for the entire symptom spectrum experienced by people with ME
It is a common mechanism involved in all neuroimmune diseases investigated thus far
In terms of MRV causation infection of BCEC s and the resulting raised levels of VEGF and MIP-1 result in activated microglia and neuroimmune pathology when MLV viruses infect other hosts
Thus the potential mechanism by which MRV infections could cause ME exists
This is not to say that MRVs do cause ME merely that the hypothesis that they do so is plausible and consilient with observations re causation of neuroimmune diseases in general and the behavior of MLV class viruses in other hosts
@D.O’Keefe 20/11
ReplyDeleteThe descent of this Blog page into the usual morass of partialist argument typical of anything related to XMRV demonstrates the desirability of urgently separating the M.E/CFS//XMRV fiasco from future MLV research. Whatever failures by whichever labs, the M.E/CFS connection was never an effectively testable hypothesis and until there is far stronger epidemiological certainty about M.E/CFS, research on MLVs as human pathogens, should be focussed on known pathological processes. Neither MLV researchers, nor M.E/CFS patients need further hypothesis stacking.
@Anon. Nov 20/1.37 pm
So everyone with a sore throat may be considered to have typhoid ? The symptomology currently accepted for case descriptions of M.E/CFS is simply too open ended to allow an implication of common causality. Of course testing the simple hypothesis of single causation is, absent of a test of prior plausibility, the most logical course – but which pathogen do you start with ? There are unlimited candidates and investigations would have to include consideration of common illness agencies acting in uncommon fashion. The very fact that Lombardi et al happened to hit the ‘right one’ first time should have been enough to raise profound scepticism of the results they presented.
@Anon. Nov 20/8.12 am
No common diagnostic selection, no common phlebotomy practice, no common age of samples or sample handling, no comparative data. Lombardi et al did not do what you apparently want it to have done.
my friend above is relying on semantics
ReplyDeletecan a neuroimmune disease stem from a single causative abnormality? yes
can mlv viruses cause neuroimmune disease yes
Is ME a neuroimmune disease yes
CFS is nothing but a metaphor and is in no way a scientific description of a disease entity
Is chronic fatigue of unknown of psychological cause and 4 minor self reported symptoms likely to have a single cause? no of course not?
CFS is a linguistic construct when you use the expanded description it soon becomes apparent that it is just a subjective label treated as an objective descrpition
BTW all patients in Lombadri satisfied the CCC diagnostic criteria which allow for a wide range of neurological immunological and endocrine abnormalities to be included in the diagnosis
In other words as confirmed by later work the patients had neuroimmune abnormalities and hence retroviral causation of these patients neurological abnormalities is entirely plausible
@Anon. Nov 20/1.37 pm
ReplyDeleteIt is possible that the ongoing metagenomics research of Dr. Ian Lipkin will provide some starting points regarding pathogens and the pathogenesis of ME/CFS - in subgroups at least - absent a determination as to whether this is one disease or a group of disparate entities which all have core symptoms in common. Biomarkers would be nice.
There is no mystery to CFS/ME. CFS leads to HIV-Negative AIDS. It horrifies me on a daily basis that the medical establishment, politicians, and media have not gotten around to reporting the fact that HIV is not the cause of AIDS. CFS/ME patients are the neglected AIDS patients.
ReplyDeleteDrug companies simply make profit convincing very healthly HIV+ people (i.e., predominantly in 3rd world countries) that they need toxic Rx's.
See how easy? It's no mystery.
Bravo to "ANON" (above) who states: "CFS is nothing but a metaphor..." I agree that these disease paradigms are such a sham.
Sit in a room with a group of "CFS" patients, a support group, perhaps, or a doctor's waiting room, and listen, just listen. The commonalities are stunning, regardless of the differences.
ReplyDeleteAlso, virtually all studies assume that the symptom picture for a "CFS" patient is fixed and stable in time. All "CFS" patients, myself included, will report new symptoms emerging over time, some old symptoms waning, etc.
But again and again, I'm struck by the commonalities amongst us "CFS" patients.
CFS is a descriptive label given to people who present with ongoing fatigue and 4 minor symptoms of unknown or psychological origin.It is not a disease entity in the sense that epilepsy of diabetes or multiple sclerosis. One cant talk about the causes of CFS because CFS has no objective existance it is merely a label of convenience. some people given a label of CFS will have an underlying nueroimmune disease so the task is not to determine the cause of a subjective label but to determine the nature of the underlying disease that people given this label of convenience have
ReplyDeleteIn this postmodern era we must always be wary of labels which suggest an objective connection with the thing so labelled when in fact they do not. CFS is just a label with no objective relationship to any disease and can be applied to anyone presenting with chronic fatigue whatever the aetiology of the fatigue.To say that CFS has multiple aetiologies is misleading because CFS is not an objective entity or disease.It can be correct to say that CFS is a label which may be given to people with diseases of entirely different aetiology.
to be given a label of ME/CFS however using the canadian criteria there needs to be neurological immunological and endocrine abnormalities in addition to fatigue and 4 minor symptoms
the patients who are mrv positive using these criteria show objective neuroimmune abnormalities and thus it is these patients with these abnormalities which are subject to the hypothesis that their neuro immune abnormalities are caused by the MRV
when one uses the term CFS one must be very specific about the underlying abnormalities found in the patients examined
Indeed the fukuda group insist that merely describing the patients in a trial as having CFS is hopelessly inadequate and the patients abnormalities should be explicitly stated
It is something akin to describing patients with chronic pain syndrome and then claiming that there is no such thing as one cause of chronic pain syndrome.!
In vitro - It doesn't sound like you know much about CFS, its symptoms, their onset, and the risk factors it creates over time. If you did, it would make more sense to you why they initially focused in on retroviruses given the "almost infinite" number of potential singular causes. The Lombardi group actually originally started with a broad net looking for any and all pathogens with an array to begin with. In fact, they state repeatedly they thought they would find a herpes virus because that had been the focus of CFS research up until that point. But, the only virus that consistently showed up across the majority of their patient samples (and not the controls) was a gamma-retrovirus that they thought was or was similar to XMRV. Given that finding, they wanted to do more research on this type of virus because in many types of animals - mice, cats, etc.. gammaretroviruses are capable of causing the same immune, neurological, and oncological problems that occur in consistently CFS patients.
ReplyDeleteMore specifically, CFS patients have been reported to have much higher rates of relatively rare leukemias and lymphomas than the general population - gamma-retroviruses like MLV are known to cause such cancers in the animals they infect. This, along with immune system problems and neurological changes/deficits reported in CFS being similar as well. In fact the whole pattern of CFS symptom exacerbation by infection and events that trigger inflammation and stress hormones mirrors exactly the observation of the course of FeLV infected cats. These retroviruses also don't cause symptoms in everyone exposed, but can at some point in their life cycle be transmitted both vertically and horizontally - which also fits the observation of how "CFS" occurs. The point is, it wasn't just a shot in the dark.. there are good reasons to suspect a gammaretrovirus might cause a symptom complex like "CFS" in humans.
These citations might also explain the initial interest in gamma-retroviruses when studying CFS:
ReplyDeleteOne of the most consistent lab abnormalities found in CFS patients is low NK cell cytotoxicity.
Suppression of natural killer cell activity by Friend murine leukemia virus.
http://www.ncbi.nlm.nih.gov/pubmed/6202923
Seems rather interesting, no? I applaud Dr O'Keefe for questioning some basic assumptions that have been made about the study of gamma-retroviruses in humans up until this point. I hope researchers stop squabbling and follow suit. There are *a lot* of unanswered questions about the pathogenicity of such viruses in humans and the best way to detect such viruses. Unfortunately, I think the current paradigm being used to decide what "is" and what "isn't" when is flawed. Perhaps thats why research into these viruses hasn't gone any where recently? People are asking the wrong questions and using the tools wrong.
Totally agree with the last two posts.
ReplyDeleteDr. O'Keefe,
ReplyDeleteThank you for having an inquisitive mind! So refreshing in the world of ME and HGRV science! And thank you for this interesting post. XMRV may be dead, but HGRVs have just been born!
Justin Reilly, esq.
taking tenofovir, azt, and raltegravir raised my nk cell function from "2" to "60". i believe healthy people are in the 60 - 80 range. i was still ill, however.
ReplyDeleteAnon, it is easy to hypotheisis that for some the downstream affects will also need treating as well. It's not as if current ARVs were designed to specifically target a potential MRV.
ReplyDelete"All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident." ~ Arthur Schopenhauer
ReplyDeleteTo Drs. Vaughan and O'Keefe.
ReplyDeleteHi, I think that what Dr. Vaughan said about so many things seeming to fit, everything except the important point of actually finding the virus, is really how it feels to me. A gammaretroviral infection would have the potential to neatly explain most all of the findings in Myalgic Encephalomyelitis (CFS).
As a background I would be interested in knowing what you both think about the study out of the Max Plank Institute that found that they could detect 'XMRV' in respiratory fluids?
Fischer N, Aepfelbacher M et al.Xenotropic murine leukemia virus-related gammaretrovirus in respiratory tract. Emerg Infect Dis. 2010 Jun;16(6):1000-2. PubMed PMID: 20507757.
The citation is above and as far as I know they have not stated this was contamination, though their subsequent study in 'XMRV' in tissue sections of prostate cancer is wholly negative:
Stieler K, Fischer N et al. No detection of XMRV in blood samples and tissue sections from prostate cancer patients in Northern Europe. PLoS One. 2011;6(10):e25592. Epub 2011 Oct 12. PubMed PMID: 22022417.
While I don't see a comment abou the detect of XMRV in the respiratary fluids, perhaps due to this latest study they think that their positive results were only due to contamination?
Here is another link to ME_RESEARCH_UK (Dundee Uni) team's studies, many of which consist of showing a large degree of inflammation, neutrophil apoptosis, and a lack of control at the junction between the meeting points of the nervous and the vascular system.
http://www.meresearch.org.uk/research/projects/completed.html
though their subsequent study in 'XMRV' in tissue sections of prostate cancer is wholly negative:
Stieler K, Fischer N et al. No detection of XMRV in blood samples and tissue sections from prostate cancer patients in Northern Europe. PLoS One. 2011;6(10):e25592. Epub 2011 Oct 12. PubMed PMID: 22022417.
While I don't see a comment abou the detect of XMRV in the respiratary fluids, perhaps due to this latest study they think that their positive results were only due to contamination?
Here is another link to ME_RESEARCH_UK (Dundee Uni) team's studies, many of which consist of showing a large degree of inflammation, neutrophil apoptosis, and a lack of control at the junction between the meeting points of the nervous and the vascular system.
http://www.meresearch.org.uk/research/projects/completed.html
_________________________________
ReplyDeleteSorry everything above the link: http://www.meresearch.org is just a repeat, sorry about that.
_________________________________
http://www.meresearch.org.uk/research/projects/completed.html
There seems to me three possibilities:
1.) MLV- related retroviruses has an airtight alibi and are simply not involved. At all.
2.) These retroviruses (MLV related viruses) cling so tightly to specific tissue locations they are simply not found in the blood; especially of patients who have been ill for a long time. I suppose the macaque studies would be a good starting point if there are researchers out there considering this a possibility.
3.) Due to immune defects, M.E. patients are terrible at making antibodies to these retroviruses. This would explain the lack of antibody findings. I think the possibility that we are terrible at making antibodies (or at least specific antibodies) is something the research world which didn't know of M.E. before this probably hasn't fully considered.
As a corollary to this I wonder if an overblown amount of inflammation, would perhaps lead to the presence of 'strange'-inflammation dependent nucleases which were not present in healthy people's blood, and which where not deactivated in a normal PCR protocol?
Anyways thanks and it would be interesting to hear both of your thoughts. It feels to me as if the "safety button" on the immune response (or at least the innate immune response) has been released and the innate immune system is reacting to everything, or perhaps in a constant state of fighting off common, daily, pathogen exposures due to a dysfunction in the adaptive immune system.
Just a hypothesis, "that happens to fit the facts." I don't know if these would necessitate a persistent viral infection or not.
Kind wishes and tc all!
John_d -- thanks for your comment; I did take a quick look at these papers -- I read all the comments on this blog and if I get a chance, look into the suggestions -- anyhow - the first paper regarding respiratory fluids - it seems that they did not look for mouse DNA contamination at all...but in at least one sample they determined 8-fold increased reverse-transcriptase activity - presumably that would not be from minute mouse contamination. As for their prostate cancer study, they looked at PBMNCs, which if you look at PMID: 21325416, you will see in macaques infected with the MLV-type XMRV, viral infection is potentially undetectable after a short time. They also looked at some tissue sections using IHC with an antibody against XMRV. It is unclear if this would detect a related virus. I also looked at the website you pointed to and some of their papers, that was interesting - especially their gene expression data from "post infectious" (?) patients - some of their top ranked genes are very highly expressed in patients with glioblastoma (in the tumors) - and recent reports suggest CMV may be an "oncoaccessory" for GBM (PMID:22090104). We also see some of these same genes upregulated in other proliferative diseases. Anyhow, I think you have given us food for thought for the moment, and the lab bench beckons.
ReplyDeletethanks,
Hi Denise
ReplyDeleteWhat are your thoughts on the EM of the budding/maturing virion and the serology assay that can only detect the SU protein of MLV viruses, not mERVs or HERVs?
You can see the maturing retrovirus in this image, it is the one with the speech bubble coming from it.
http://2.bp.blogspot.com/_zE8CzamN1Y0/TQ-okAgIPGI/AAAAAAAABlo/Mz77Y38tfW0/s400/xmrv.jpg
I am also interested in your thoughts about the paper Lombardi et al. and the need to now fully sequence the viruses found in that paper. With Mikovits and Ruscetti's partial sequences being polytropic, do you not agree those should be fully sequenced first before anyone should declare the findings to be different?
Thank you
"2.) These retroviruses (MLV related viruses) cling so tightly to specific tissue locations they are simply not found in the blood; especially of patients who have been ill for a long time. I suppose the macaque studies would be a good starting point if there are researchers out there considering this a possibility."
ReplyDelete@John_d
Gamma retroviruses, like delta and beta retroviruses are rarely found in the blood as they preferentially propagate in tissue through clonal expansion. Hence why the sequence diversity is narrow.
I would be most interested what studies of "neuromuscular pathology" with regards to ME/CFS you have used for comparison.
ReplyDelete(And the choice of fonts is most unfortunate and makes it EXTREMELY hard to read anything here – BTW I think these fonts would be more fitting for a comic than for science blog…)
ReplyDeleteI then wonder if anyone actually did find polytropic/xenotropic MLVs in human disease, would they be able to publish it? Would it not get held back by virtue of the already published negative data, which in most cases was poorly controlled for or maybe not the appropriate source of tissue? Just a thought.
ReplyDeleteAnd I wonder if you need a new blade for your Occam Razor™©.
Could it just be that maybe possibly if over a dozen groups of retrovirologists were looking for XMRV (and possibly other MLV-related viruses) in the blood of patients like it was the Goldrush would all turn up empty handed because, well, the explanation that makes the fewest new assumptions and that would fit the results would be that there isn't any MLVs in patients – and probably no other (gamma-)retroviruses as well? Instead of making convoluted assumptions that it actually might hide in the tissue?
Occam Razor™© – ruining convoluted theories since 1495.
This comment has been removed by the author.
ReplyDeleteWith regards to all the claims about VP62 not being the "right" virus to look for: That is EXACTLY what Lombardi et. al. stated to have found and matches EXACTLY the gene-sequences published by Lombardi/Mikovits/WPI. The correct scientific term for these VP62 claims is "Red Herring".
ReplyDeleteI am not entirely convinced that polytropic or other MLVs aren't infecting humans.
ReplyDeleteYou can extent that argument to ALL viruses.
The only reason that scientists were looking very very intensely at MLVs is because somebody said "We found MLVs in prostate cancer!" and then somebody said "Me too in CFS!". The last one is most definitely a contamination with XMRV plasmid, which IMHO was intentional. The first one is most likely lab contamination.
After all this research, I am reasonably certain that the one thing NOT causing human disease is MLVs.
(Besides, we have lived with mice for 10.000s of years. If we had gotten pathogenic viruses from them, they would be very very ubiquitous and possibly found in humans a long time ago. Not to mention that we would find associated cancers. I know, Occam's Razor is a heartless bitch)
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ReplyDeleteSpam from "fatigue care", a ayurveda quack. Great.
ReplyDelete