Author Topic: XMRV is capable of infecting laboratory mice as well as humans  (Read 1069 times)

Gerwyn

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The mouse xenotropic MLVs (X-MLVs) were originally defined by their inability to infect cells of their natural mouse hosts. It is now clear, however, that X-MLVs actually have the broadest host range of the MLVs. Nearly all nonrodent mammals are susceptible to X-MLVs, and all species of wild mice and several common strains of laboratory mice are X-MLV susceptible.

obviously dr Pathak,s researchers have let him down in this matter because his conclusion that lab mice could not have been infected  by PCR negative XMRV and thus  must have been transfered  to  the cell line from the mice that might have been used  in xenograft formation is  in the light of the above evidence totally unsupportable

http://www.retrovirology.com/content/7/1/101

Daisymay

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #1 on: March 11, 2011, 03:32:14 PM »
Wow! Great find......surely all these researchers, Coffin etc must have known of this???

Eric

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #2 on: March 13, 2011, 05:51:04 AM »
Hmmm this seems like a pretty good point, I'm mindful in this connexion of the Norbert Bannert paper you posted a year ago on PCR(-) infections.

What if you were to passage material from a nude mouse (the strain in question) into a clean but susceptible individual of a true-breeding (ie inbred homozygous) strain. Would there always be a PCR+ phase early on? If so you mgiht be able to assess more strictly whether nude mouse really cannot harbor the virus.

If nude mouse doesn't have a permissive XPR1 allele, then infection would be very unlikely to be possible - but I don't think we should in that case assume that it's absolutely impossible. That's not how the game is played.

awol

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #3 on: March 13, 2011, 07:52:09 AM »
Just to clarify -

"Capable of infecting mice "is not the same as "found in lab mice" right? I have been quite sure for a while now that this virus does not exist so far in mice. Am I wrong?

Natasa

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #4 on: March 13, 2011, 10:18:37 AM »
If nude mouse doesn't have a permissive XPR1 allele, then infection would be very unlikely to be possible - but I don't think we should in that case assume that it's absolutely impossible. That's not how the game is played.

Now who was it that found xmrv infection in cells (human prostate I think) that didn't express XPR1 and said they need to look for other entry receptors...? will try to dig it out.


Natasa

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #5 on: March 13, 2011, 10:31:24 AM »
oh yes here it is:

J Virol. 2010 Jul;84(13):6288-96. Epub 2010 Apr 21.
Evaluation of cellular determinants required for in vitro xenotropic murine leukemia virus-related virus entry into human prostate cancer and noncancerous cells.

Bhosle S, Suppiah S, Molinaro R, Liang Y, Arnold R, Diehl W, Makarova N, Blackwell J, Petros J, Liotta D, Hunter E, Ly H.
Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, USA.

The newly identified retrovirus-the xenotropic murine leukemia virus-related virus (XMRV)-has recently been shown to be strongly associated with familial prostate cancer in humans (A. Urisman et al., PLoS Pathog. 2:e25, 2006). While that study showed evidence of XMRV infection exclusively in the prostatic stromal fibroblasts, a recent study found XMRV protein antigens mainly in malignant prostate epithelial cells (R. Schlaberg et al., Proc. Natl. Acad. Sci. U. S. A. 106:16351-16356, 2009). To help elucidate the mechanisms behind XMRV infection, we show that prostatic fibroblast cells express Xpr1, a known receptor of XMRV, but its expression is absent in other cell lines of the prostate (i.e., epithelial and stromal smooth muscle cells). We also show that certain amino acid residues located within the predicted extracellular loop (ECL3 and ECL4) sequences of Xpr1 are required for efficient XMRV entry. Although we found strong evidence to support XMRV infection of prostatic fibroblast cell lines via Xpr1, we learned that XMRV was indeed capable of infecting cells that did not necessarily express Xpr1, such as those of the prostatic epithelial and smooth muscle origins. Further studies suggest that the expression of Xpr1 and certain genotypes of the RNASEL gene, which could restrict XMRV infection, may play important roles in defining XMRV tropisms in certain cell types. Collectively, our data reveal important cellular determinants required for XMRV entry into different human prostate cells in vitro, which may provide important insights into the possible role of XMRV as an etiologic agent in human prostate cancer.
full version http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2903252/?tool=pubmed


So why is presence of Xpr1 taken as a GIVEN when talking about mice/animal susceptibility to XMRV? Methinks this need for Xpr1 could easily turn out to be just another myth...

Natasa

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #6 on: March 13, 2011, 10:50:33 AM »
from above  ... Collectively, these results suggest that, in the absence of XPR1 expression, XMRV can use alternative receptor(s) and/or mechanism(s) to gain entry into cells. Additional studies are required in order to elucidate the exact alternative mechanism(s) of XMRV virus entry into cells.

Gerwyn

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #7 on: March 13, 2011, 09:26:30 PM »

yep that is the point it was once thought that polys and xenos only used XPR-1  that is now known not to be the case

Gerwyn

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #8 on: March 13, 2011, 09:27:26 PM »
Wow! Great find......surely all these researchers, Coffin etc must have known of this???

yes of course they do

Tango

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #9 on: March 13, 2011, 09:37:53 PM »
There is a lot that those researchers know.   >:(
"I suspect there have been a number of conspiracies that never were described or leaked out. But I suspect none of the magnitude and sweep of Watergate." Woodward

"I would favor any name that does not impose (or give the appearance of imposing) taxonomic preconceptions on the nomenclature." Coffin

Jaz

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #10 on: March 14, 2011, 05:44:15 AM »
Do we have proof they really know it?  It sure seems like they don't. 
The goal is not to bring your adversaries to their knees but to their senses. -- Gandhi

Robyn

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #11 on: March 14, 2011, 05:57:52 AM »
There could be a very good reasons they would rather not mention it.

Tango

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Re: XMRV is capable of infecting laboratory mice as well as humans
« Reply #12 on: March 14, 2011, 01:32:59 PM »
This is what they are working on - of course they know.  They will even know about all the research that is going to come out
"I suspect there have been a number of conspiracies that never were described or leaked out. But I suspect none of the magnitude and sweep of Watergate." Woodward

"I would favor any name that does not impose (or give the appearance of imposing) taxonomic preconceptions on the nomenclature." Coffin