Endogenous retroviruses/potential hazards for vaccines

FernRhizome

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Any of you good science folks able to help us interpret this one? Does anyone have access to the full paper? How does this connect to
1) the current ancient retrovirus study from Chicago/Tufts that some of us are participating in
2) pet transmission
3) vaccines
4) XMRV? ~fern

Biologicals. 2010 Apr 7. [Epub ahead of print]
Endogenous retroviruses as potential hazards for vaccines.
Miyazawa T.
Laboratory of Signal Transduction, Department of Cell Biology, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Abstract
Retroviruses are classified as exogenous or endogenous according to their mode of transmission. Generally, endogenous retroviruses (ERVs) are not pathogenic in their original hosts; however, some ERVs induce diseases. In humans, a novel gammaretrovirus was discovered in patients with prostate cancer or chronic fatigue syndrome. This virus was closely related to xenotropic murine leukemia virus (X-MLV) and designated as xenotropic murine leukemia virus-related virus (XMRV). The origin and transmission route of XMRV are still unknown at present; however, XMRV may be derived from ERVs of rodents because X-MLVs are ERVs of inbred and wild mice. Many live attenuated vaccines for animals are manufactured by using cell lines from animals, which are known to produce infectious ERVs; however, the risks of infection by ERVs from xenospecies through vaccination have been ignored. This brief review gives an overview of ERVs in cats, the potential risks of ERV infection by vaccination, the biological characteristics of RD-114 virus (a feline ERV), which possibly contaminates vaccines for companion animals, and the methods for detection of infectious RD-114 virus. Copyright 2010 The International Association for Biologicals. Published by Elsevier Ltd. All rights reserved.
PMID: 20378372 [PubMed - as supplied by publisher]

http://www.ncbi.nlm.nih.gov/pubmed/20378372
 
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Gerwyn

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Any of you good science folks able to help us interpret this one? Does anyone have access to the full paper? How does this connect to
1) the current ancient retrovirus study from Chicago/Tufts that some of us are participating in
2) pet transmission
3) vaccines
4) XMRV? ~fern

Biologicals. 2010 Apr 7. [Epub ahead of print]
Endogenous retroviruses as potential hazards for vaccines.
Miyazawa T.
Laboratory of Signal Transduction, Department of Cell Biology, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Abstract
Retroviruses are classified as exogenous or endogenous according to their mode of transmission. Generally, endogenous retroviruses (ERVs) are not pathogenic in their original hosts; however, some ERVs induce diseases. In humans, a novel gammaretrovirus was discovered in patients with prostate cancer or chronic fatigue syndrome. This virus was closely related to xenotropic murine leukemia virus (X-MLV) and designated as xenotropic murine leukemia virus-related virus (XMRV). The origin and transmission route of XMRV are still unknown at present; however, XMRV may be derived from ERVs of rodents because X-MLVs are ERVs of inbred and wild mice. Many live attenuated vaccines for animals are manufactured by using cell lines from animals, which are known to produce infectious ERVs; however, the risks of infection by ERVs from xenospecies through vaccination have been ignored. This brief review gives an overview of ERVs in cats, the potential risks of ERV infection by vaccination, the biological characteristics of RD-114 virus (a feline ERV), which possibly contaminates vaccines for companion animals, and the methods for detection of infectious RD-114 virus. Copyright 2010 The International Association for Biologicals. Published by Elsevier Ltd. All rights reserved.
PMID: 20378372 [PubMed - as supplied by publisher]

http://www.ncbi.nlm.nih.gov/pubmed/20378372
retroviruses are either endogenous or exogenous based on whether they are replicative or not.Exogenous viruses can be transmitted vertically or horizontally.Endogenous viruses can only be transmitted vertically and are not infectious.

No XMRV was not derived from an endogenous virus but an exogenous Mulv which jumped species.This is called zoonosis.There is no such thing as an inectious erv otherwise by definition it would not be an erv.X_Mlv,s are not ervs of mice of any kind.XMRV can no longer infect mice and have not been able to do so for about 60 years.
 

FernRhizome

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Right, it sounds to me like X-MLV did jump. I think, maybe from the abstract, it was thought that X-MLV was THOUGHT to not be able to jump, but then it did. That's why it wasn't discovered earlier, no one thought it could do the jump. So am I interpreting the extract right that the author is postulating that it might have jumped into cats via pet vaccinations? Or that this is a potential area to explore? I think we need access to the entire paper to know for sure. Can anyone get it? ~Fern
 

JillBohr

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Right, it sounds to me like X-MLV did jump. I think, maybe from the abstract, it was thought that X-MLV was THOUGHT to not be able to jump, but then it did. That's why it wasn't discovered earlier, no one thought it could do the jump. So am I interpreting the extract right that the author is postulating that it might have jumped into cats via pet vaccinations? Or that this is a potential area to explore? I think we need access to the entire paper to know for sure. Can anyone get it? ~Fern
Fern, I interpreted this paper the same way you did. They thought it could not jump but it did. However, I am not very smart when it comes to science. I was great in math and business but that is it. I hope someone will post the whole paper and the smart people here that know what they are doing can comment on it. This looks very interesting.

One more thing, I cannot access the library here and there have been several occasions when someone did post a paper and I could not access it. Is there anyway to change that?
 

JillBohr

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It looks like this paper is a follow up on where they did find an endogenous retrovirus in a live vaccine for pets.
http://jvi.asm.org/cgi/content/abstract/JVI.02715-09v1

The genomes of all animal species are colonized by endogenous retroviruses (ERVs). Although most ERVs have accumulated defects that render them incapable of replication, fully infectious ERVs have been identified in various mammals. In this study, we isolated a feline infectious ERV (RD-114) in a proportion of live attenuated vaccines for pets. Isolation of RD-114 was made in two independent laboratories using different detection strategies and using vaccines for both cats and dogs commercially available in Japan or the United Kingdom. This study shows that the methods currently employed to screen veterinary vaccines for retroviruses are inadequate and should be re-evaluated.
 
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Gerwyn

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"however, some ERVs induce diseases."

I don't get it. Is Miyazawa wrong then?
hi Julius
to date Hervs have not been shown to cause any human diseases quite the reverse.protein expression is found in a number of illbesses such as RA.Ervs are expreesed as part of the intrisic defences and thus far they have not been shown to cause any human diseases
 
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Gerwyn

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Right, it sounds to me like X-MLV did jump. I think, maybe from the abstract, it was thought that X-MLV was THOUGHT to not be able to jump, but then it did. That's why it wasn't discovered earlier, no one thought it could do the jump. So am I interpreting the extract right that the author is postulating that it might have jumped into cats via pet vaccinations? Or that this is a potential area to explore? I think we need access to the entire paper to know for sure. Can anyone get it? ~Fern
all exogenous retoviruses have the potential to jump back and fore between mammalian species.

The mechanism appeard to be achieved by incoporating ERV proteins into their coat as substituting a protein in the receptor specific area.

This changes the shape of the viral envelpoe so it can no longer infect its current host but can engage with cellular receptors of another species and infect them instead
 

natasa778

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there is a long thread on this topic of contamination titled "Mouse retrovirus in production of biologicals in "XMRV Testing, treatment and transmission" section.
 

natasa778

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I don't get it. Is Miyazawa wrong then?
No.

Gerwyn explained why, ERVs are not infectious in host species (according to current science) but can become that, once they cross species. Once they do they are not ERVs (endogenous) to that new host.
 

JillBohr

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No.

Gerwyn explained why, ERVs are not infectious in host species (according to current science) but can become that, once they cross species. Once they do they are not ERVs (endogenous) to that new host.
So..... the XMRV is an extrogenous virus which is dangerous. Right? So sorry but I am having difficulty wrapping my brain around this. Honestly, I did not know any of these terms until recently. I was so happy to get my 15 credit hours of science BER's when I was a college student and I never thought I would ever have to deal with science again once I got out. Oy!
 

gracenote

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One more thing, I cannot access the library here and there have been several occasions when someone did post a paper and I could not access it. Is there anyway to change that?
Hi Jill,

You will have access to the library when you reach 100 posts; you only have 9 to go. Or, you can request admission from a moderator.
 

Bob

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retroviruses are either endogenous or exogenous based on whether they are replicative or not.Exogenous viruses can be transmitted vertically or horizontally.Endogenous viruses can only be transmitted vertically and are not infectious.

No XMRV was not derived from an endogenous virus but an exogenous Mulv which jumped species.This is called zoonosis.There is no such thing as an inectious erv otherwise by definition it would not be an erv.X_Mlv,s are not ervs of mice of any kind.XMRV can no longer infect mice and have not been able to do so for about 60 years.
Gerwyn, hasn't there been some research that demonstrates that endogenous retroviruses can become infectious again?...
www.ncbi.nlm.nih.gov/pmc/articles/PMC2648265/?tool=pubmed

Previously discussed on the forum here:
http://www.forums.aboutmecfs.org/sh...-recombination-and-relevance-for-xmrv-in-xand

A quote from the Abstract:
The endogenous retroviruses infect and are integrated into target cell genomes and subsequently replicate and spread as pseudotyped viruses.
Also, I understood that the original mouse virus is endogenous in mice... isn't that the case?

It is thought that the RNA/DNA of an endogenous animal virus could be present in vaccines and that could be a route for the virus to jump species and mutate.
 

kurt

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hi Julius
to date Hervs have not been shown to cause any human diseases quite the reverse.protein expression is found in a number of illbesses such as RA.Ervs are expreesed as part of the intrisic defences and thus far they have not been shown to cause any human diseases
Gerwyn, do you have a reference for this? I have read a number of papers suggesting exactly the opposite. The research evidence for specific mechanisms is growing, what do you mean by 'they have not been shown' - absolute proof may be lacking still but the idea that HERVs can be involved in disease is far from disproven.

Here is an example of the literature, this is older, but a good synopsis, there is an extensive literature since this time.

Clin Microbiol Rev. 1996 Jan;9(1):72-99.
Human endogenous retroviruses: nature, occurrence, and clinical implications in human disease.
Urnovitz HB, Murphy WH.

Calypte Biomedical Corporation, Berkeley, California 94710, USA. hervdoc@aol.com
Comment in:

Clin Microbiol Rev. 1996 Oct;9(4):585.
Abstract
Retroviral diagnostics have become standard in human laboratory medicine. While current emphasis is placed on the human exogenous viruses (human immunodeficiency virus and human T-cell leukemia virus), evidence implicating human endogenous retroviruses (HERVs) in various human disease entities continues to mount. Literature on the occurrence of HERVs in human tissues and cells was analyzed. Substantial evidence documents that retrovirus particles were clearly demonstrable in various tissues and cells in both health and disease and were abundant in the placenta and that their occurrence could be implicated in some of the reproductive diseases. The characteristics of HERVs are summarized, mechanisms of replication and regulation are outlined, and the consistent hormonal responsiveness of HERVs is noted. Clear evidence implicating HERV gene products as participants in glomerulonephritis in some cases of systemic lupus erythematosus is adduced. Data implicating HERVs as etiologic factors in reproductive diseases, in some of the autoimmune diseases, in some forms of rheumatoid arthritis and connective tissue disease, in psoriasis, and in some of the inflammatory neurologic diseases are reviewed. The current major needs are to improve methods for HERV detection, to identify the most appropriate HERV prototypes, and to develop diagnostic reagents so that the putative biologic and pathologic roles of HERVs can be better evaluated.

PMID: 8665478 [PubMed - indexed for MEDLINE]PMCID: PMC172883Free PMC Article
The full paper is available free here:

Human endogenous retroviruses: nature, occurrence, and clinical implications in human disease.
 
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Gerwyn

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Gerwyn, do you have a reference for this? I have read a number of papers suggesting exactly the opposite. The research evidence for specific mechanisms is growing, what do you mean by 'they have not been shown' - absolute proof may be lacking still but the idea that HERVs can be involved in disease is far from disproven.

Here is an example of the literature, this is older, but a good synopsis, there is an extensive literature since this time.

An idea is not a hypothesis.A hypothesis is based on observation.To date Hervs have not been shown to cause disease in humans.The part thet HERVS have shown to cause disease would need to be referenced.The article you referenced is interesting thankyou.Nothing has been added in terms of HERV since the 1996 article.Herv proteins are expressed for many reasons normally as part of the intrinsic immune system and hence mostly beneficial.Hervs have been suspected as potential pathogens in a number of illnesses but thus far there hasnt been an attempt at constructing a testable hypothesis that can be disproved let alone anything else.The suspected invovement in MS has not withstood the scrutiny of the recent paper investigating EBV and MS posted elsewhwere on the forum
 
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Gerwyn

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Gerwyn, hasn't there been some research that demonstrates that endogenous retroviruses can become infectious again?...
www.ncbi.nlm.nih.gov/pmc/articles/PMC2648265/?tool=pubmed

Previously discussed on the forum here:

Not really Bob Endo RNA can be expressed and could potentially combine with exogenous viral RNA.This was an in vitro experiment most ERVs are only fragments of ancient retroviruses which dont have replicative capacity.XMRV was a mouse virus but an exogenous one.It appears to have incorporated some erv protein into its envelope changing its surface receptor