C
cold_taste_of_tears
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Found this information on another site, and no one answered the person posting it. There are many genius minds here (sadly I am not of them!).
So I thought this was the ideal place to ask you guys - what you think of this.
Should the WPI know about this?
We already have the incredible Elaine De Freitas link to CFIDS associated Retrovirus. How about this?
It was only published 8 weeks ago.
Journal of Retrovirology, Sept 2009
Stang A, et al
Department of Molecular and Medical Virology, Ruhr-University Bochum, Germany
Available online at: http://www.retrovirology.com/content/6/1/86
----------------------------------------------------------------------
Unintended spread of a biosafety level 2 recombinant retrovirus
abstract:
“Gene fragments for both viruses could be detected in a broad range of permissive cell lines from multiple species. Furthermore, experimental infections of cells negative for these viruses showed that both viruses replicate rapidly to high loads. We decided to further analyze the genomic sequence of the MuLV-like contaminant virus. 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.”
In detail:
''It 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 as determined by viral RNA copy numbers in the supernatants and proviral genome copies of extracted cellular DNA. In the early stage of infection even some cytopathic effects (CPE) could be observed. In contrast, no CPE was seen in persistently infected cultures possibly due to adaptation of cells to the retroviral infection.”
2 - “In summary, there have been numerous publications about retroviral contaminations like recent reports of ecotropic murine leukemia virus in various cell lines. The most frequent retrovirus found in this context is squirrel monkey retrovirus (SMRV). One study even reported the detection of SMRV related sequences in commercial interferon preparations in 1998. 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.
“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 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.”
---------------------------------------------------------------------
Further reading:
Generation of helper-free amphotropic retroviruses that transduce a dominant-acting, methotrexate-resistant dihydrofolate reductase gene
(1985)
Redesign of retrovirus packaging cell lines to avoid recombination leading to helper virus production,(1986).
So I thought this was the ideal place to ask you guys - what you think of this.
Should the WPI know about this?
We already have the incredible Elaine De Freitas link to CFIDS associated Retrovirus. How about this?
It was only published 8 weeks ago.
Journal of Retrovirology, Sept 2009
Stang A, et al
Department of Molecular and Medical Virology, Ruhr-University Bochum, Germany
Available online at: http://www.retrovirology.com/content/6/1/86
----------------------------------------------------------------------
Unintended spread of a biosafety level 2 recombinant retrovirus
abstract:
“Gene fragments for both viruses could be detected in a broad range of permissive cell lines from multiple species. Furthermore, experimental infections of cells negative for these viruses showed that both viruses replicate rapidly to high loads. We decided to further analyze the genomic sequence of the MuLV-like contaminant virus. 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.”
In detail:
''It 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 as determined by viral RNA copy numbers in the supernatants and proviral genome copies of extracted cellular DNA. In the early stage of infection even some cytopathic effects (CPE) could be observed. In contrast, no CPE was seen in persistently infected cultures possibly due to adaptation of cells to the retroviral infection.”
2 - “In summary, there have been numerous publications about retroviral contaminations like recent reports of ecotropic murine leukemia virus in various cell lines. The most frequent retrovirus found in this context is squirrel monkey retrovirus (SMRV). One study even reported the detection of SMRV related sequences in commercial interferon preparations in 1998. 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.
“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 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.”
---------------------------------------------------------------------
Further reading:
Generation of helper-free amphotropic retroviruses that transduce a dominant-acting, methotrexate-resistant dihydrofolate reductase gene
(1985)
Redesign of retrovirus packaging cell lines to avoid recombination leading to helper virus production,(1986).