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Unintended spread of a biosafety level 2 recombinant retrovirus

Discussion in 'XMRV Testing, Treatment and Transmission' started by natasa778, Jul 19, 2010.

  1. natasa778

    natasa778 Senior Member

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    Surprisingly it was neither identical to MuLV nor to the novel xenotropic MuLV related retrovirus (XMRV) but showed 99% identity to a synthetic retrovirus which was engineered in the 1980s.


    full text http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2760500/?tool=pubmed

    ... we found 12 sequences in the RNA preparation that showed high similarity scores (97-100%) to five different regions within either the gag and pol gene or the LTR region of squirrel monkey retrovirus (SMRV, Fig. ​Fig.2A)2AFigure 2) by analyses on nucleotide level. Additionally we isolated seven clones that bore six different sequences with high similarity scores of 97-100% to murine leukemia virus strains (MuLV) in a nucleotide BLAST search. These sequences were located within the LTR and the gag, pol and env genes...

    ... The resulting sequence of the simian retrovirus (7.968 kbp) confirmed our preliminary identification as squirrel monkey retrovirus [GenBank: M23385.1] with an overall sequence identity of 98,5%. In contrast the 7.4 kbp sequence of the murine retrovirus was neither identical to one of the murine leukemia viruses nor to XMLV but showed an overall similarity score of 99% to pAMS [GenBank: AF010170], a plasmid carrying the proviral sequence of a recombinant hybrid virus. This construct was engineered in the 1980s and is composed of sequences from Moloney murine leukemia virus (MoMLV) and amphotropic mouse leukemia virus clone 4070A [7,8]. In the current GenBank entry it is described as "... reference retrovirus for FDA validation of retrovirus vectors used for human gene therapy...". Neither the hybrid virus itself nor the plasmid pAMS were ever used in our laboratory. Due to the high identity of nucleotide sequence and the fact that the structure of MoMLV and amphotropic leukemia virus related segments is 100% identical to that of pAMS (data not shown) we can exclude that the contaminant virus is a natural recombinant of MoMLV and amphotropic leukemia virus.

    .... t has to be mentioned that each of both viruses was found in at least one aliquot of all cell lines tested. Thus, we cannot report a single cell line which is not permissive for one of both viruses. Furthermore, experimental infections of retrovirus-negative aliquots of selected cell lines showed that both viruses are highly infectious and propagate to high viral loads...

    ... In summary, there have been numerous publications about retroviral contaminations like recent reports of ecotropic murine leukemia virus in various cell lines [11,12]. The most frequent retrovirus found in this context is squirrel monkey retrovirus (SMRV) [13-16]. One study even reported the detection of SMRV related sequences in commercial interferon preparations in 1998 [17]. Although the sequences were found only as DNA and therefore rather derived from cellular DNA carrying proviral genomes than viral particles, it clearly demonstrated the contamination of the interferon producing cell line with SMRV. Germany's Central Commission of Biosafety (ZKBS) recently reported that SMRV was detectable in 128 samples of 4279 cell cultures from different laboratories throughout the country [18].
    The present report extents these studies by identifying for the first time a presumably synthetic chimeric retrovirus as a contaminant. This gene-modified organism seems to have replicated and spread intensely in a broad set of cell lines for several years without being noticed. This hybrid amphotropic/Moloney murine leukemia virus was engineered in the 1980s [7,8] and neither the virus itself nor the plasmid (pAMS) containing its proviral genome were ever used in our laboratory. Although the precise source for the contamination could not be traced back, sharing cell lines with other laboratories seems the most likely explanation....
  2. RustyJ

    RustyJ Contaminated Cell Line 'RustyJ'

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    Scary! Thanks for picking up Natasa.
  3. Stone

    Stone Senior Member

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    O...M...G...:eek: Holy rodents! At first reading, this makes my blood run cold, and would seem to explain why our government (CDC in particular) seems to be so heavily invested in squashing any retroviral theories related to CFS. I've been trying, as most of us have, to figure out what the government has to gain by s-canning CFS research for so long and in such a blatantly biased fashion. These things are almost always motivated by money, power/prestige/control, sex, or avoidance of culpability. I think we can rule out number three, which leaves money, power/prestige/control and culpability (or some combination thereof) as possible motivating factors for the inexplicably dismal failure of the governmental health agencies (who do otherwise know how to do their jobs) to find real medical answers to CFS, preferring to 'psychologize' this disease in the face of thousands of studies to the contrary.

    Most of this article is way above my pay-grade but if I'm comprehending the general thrust of it, this doesn't look like a good thing. Is it possible that this might actually be just a whisper of a larger issue and that later we could find there's more to this than currently meets the eye or am I just reading something into this that isn't there? If there were a synthetic virus which was cloned or otherwise synthesized for research purposes which inadvertently 'escaped' into the human population in the 1980's and just happens to be almost identical to XMRV, and might normally be missed by some of the more common methods of detecting such things, it sure would go quite a ways in explaining some things which have seemingly defied logical explanation for some time.

    Again, I'm sure I am misunderstanding the better part of this, and would LOVE for someone more knowledgeable to kindly shed some light on this for the rest of us mere mortals. :worried: Will someone please tell me I've got it all wrong and this is no big deal?
  4. Stone

    Stone Senior Member

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    Really? No comments on this from anyone? Hmmm. Interesting.
  5. SOC

    SOC Moderator and Senior Member

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    This shouldn't be way above my pay-grade, but it is. **sigh** D@mn*d cognitive dysfunction.

    I, too, need someone to translate this for me. I can't even maintain focus long enough to get the slightest grip on it.:sad:

    Maybe it's just because it's the end of a long day and I have to see my PCP tomorrow (never fun), but this whole ME/CFS/XMRV thing sounds to me more and more and more like a bad sci-fi movie every minute.

    Hoping a night's sleep will help me make better sense of all this mess.
  6. ixchelkali

    ixchelkali Senior Member

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    Yeah, I came across this last November and posted about it on another forum. I had a sort of YIKES :eek: reaction, but no one else seemed overly interested. I'm glad I'm not the only one to find it intriguing Here's what I posted back then:

    Huh? Excuse me, what did you say? They engineered synthetic murine leukemia virus-like viruses in the 1980’s? And it has accidently escaped?:worried:


    I found the two abstracts about engineered murine leukemia virus this article cited from the 1980’s on PubMed, both authored by Miller AD: “Generation of helper-free amphotropic retroviruses that transduce a dominant-acting, methotrexate-resistant dihydrofolate reductase gene,” (1985) and “Redesign of retrovirus packaging cell lines to avoid recombination leading to helper virus production,” (1986).

    So, they were engineering retroviruses in the 1980’s, some of them have escaped and contaminated cell lines “for several years without being noticed,” they are highly infectious, and some have even ended up in interferon preparations. Hmmm....

    Can somebody with a better understanding of these things explain why I shouldn’t find this disturbing? Or why people who DO understand this stuff aren’t alarmed? Or are they?
  7. Stone

    Stone Senior Member

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    Yes, definitely a sci-fi movie, but a GOOD one. I love GOOD sci-fi and hate bad sci-fi with a white-hot passion. I don't know how I can love one end of a spectrum so much and hate the other end so intensely, but I do. This whole CFS epic would make a far, far better sci-fi premise than Dune or whatever your favorite is. Truth is 'stranger' than fiction, but what if the truth is full of fiction and the fiction is all twisted to s*#% to look like truth? It's all a crazy mixed up thing. Real truth often appears upside down at first glance. Remember the guy who merely suggested that doctors wash their hands after autopsies before attending women at childbirth? They thought he was a mental defective. This is tiring for me too. Maybe I can find a nine-year-old to explain it to me; I usually have to find one to set my digital alarm clock, so this shouldn't be too hard, LOL. But really, for goodness sake, there are people on this forum who can contribute something to this I'm sure. If not, what do you think of sending it to one of the scientists we read about DAILY for comment? It seems like something worthy of comment to me. Does anyone else share this opinion?
  8. Stone

    Stone Senior Member

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    Good luck with your PCP. It's always a challenge to see the PCP, and if it's not offensive to you, please accept my best wishes and prayers for success. It's too bad so many of us have to dread our visits to our PCP's. I can relate, but I'll spare you the details, which I suspect are similar to your own. Let me know how it goes if you care to share publicly or privately. Feel better soon, friend. One 'convenient' thing about CFS is that it's always there, right where you left it (for now anyway). We'll resume our discussion about the possible retroviral apocalypse another time. :)
  9. bullybeef

    bullybeef Senior Member

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  10. xrayspex

    xrayspex Senior Member

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    hmmm, I also would love to hear more interpretation of this from science-trained folks
  11. SOC

    SOC Moderator and Senior Member

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    LOL! Our PCP fired us today! I posted a few details in the Community Lounge. After talking with my PCP, a retroviral apocalypse seems even more likely.... ;)
  12. Mya Symons

    Mya Symons Mya Symons

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    I read an article like this a few months ago and just for the heck of it I played on the internet until I came across a professor who used to lecture about how dangerous it would be to have a virus used for Gene Therapy get out of the lab and spread. This professor claimed this was inevitable if it hadn't happened yet. (Apparently they tried to use a retroviruses and adenoviruses for gene therapy in the past). So, I emailed him and asked him if he thought it was possible that human XMRV was one of these viruses used in experiments and if it was possible that it got out of the lab. All he emailed back was "Yes", which was a little creepy.

    Here is a link to one of those article abstracts: http://www.ncbi.nlm.nih.gov/pubmed/12052081
  13. taniaaust1

    taniaaust1 Senior Member

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    thanks for posting this.. Interesting.

    We have to wonder where the XMRV came from. natural or synthetic
  14. RustyJ

    RustyJ Contaminated Cell Line 'RustyJ'

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    From some of the posts on other threads, ME seems to have been around for a long time... before scientists began tinkering with retroviruses? If it is artificial, then you have to wonder about the transmission method. Would this rule out vaccinations or not?

    Are there any specific markers for differentiating whether a virus is artificial or not? Could any of these be applied to XMRV?
  15. xrayspex

    xrayspex Senior Member

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    whoa that is fascinating that prof wrote you back! if you dont mind backchannel me, I would like to know whe he is and his work, maybe he could help
  16. caledonia

    caledonia

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    Sorry, I didn't see this before now. Interesting thread, especially the bit about the professor.
  17. taniaaust1

    taniaaust1 Senior Member

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    Thanks for your comment rusty.. i wasnt thinking clearly. Yes CFS/ME has been around for a long time so it cant be a man made thing.
  18. RustyJ

    RustyJ Contaminated Cell Line 'RustyJ'

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    Tania, it happens to all of us. However I wouldn't be too hasty to backtrack in this instance. We do know something like CFS/ME has been around a long time, but not all cases will prove to be as a result of XMRV. There is still room for your earlier supposition.

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