XMRV CROI abstract - Viral Kinetics, Tissue Tropism, and Ser. Markers of Infection

[Esther12]

http://www.retroconference.org/2010/Abstracts/39393.htm

 

[Robin]

Wow, thanks Esther.

Of interest, the earliest leukocyte targets were CD4+ T cells and NK cells followed by CD8+ enriched T and CD20+ enriched B cells (50% positive); CD14+ monocytes were negative.

Well, look at that! CD4/8 and NK cells! Sound familiar?

I have to admit that this was painful to read. I understand why animal studies are so important to medical science but I just wish there was another way. Primates are so amazing and beautiful.

 

[Gerwyn]

http://www.retroconference.org/2010/Abstracts/39393.htm[/QUOTEthe

they looked for the virus 144 days after infection the london study tried it in 18 bl**dy HOURS

 

[Kati]

Esther this is fantastic, thank you. We now understand why the CDC thinks that Reeves had to go???


In regards to primates, it is indeed sad for these animals, however necessary for advance of research. I am thankful that the studies are coming out and there are lots of people that are working in the XMRV research, clinically, in the lab and eventually politically.

 

[gracenote]

http://www.retroconference.org/2010/Abstracts/39393.htm[/QUOTEthe

they looked for the virus 144 days after infection the london study tried it in 18 bl**dy HOURS

Gerwyn,

Maybe I'm not getting it, but wouldn't CFS patients, by definition, have had to have been "infected" (if that's what happened), and have developed symptoms, for at least 6 months to even get a diagnosis of CFS?

Are you confusing "infection" with "culturing" the virus for purposes of testing? I don't think the abstract mentioned anything about culturing the blood. (I realize my terminology is probably off. I have trouble following all this.) Just looks to me like you're comparing two different things.

​

 

[Robin]

Oh, and Esther? Your title is a little incorrect.

Preliminary results showed evidence of detectable reactivity to all 3 antigens in a low proportion (~0.1%) of US blood donors.

Donors are a biased sample of the US population (and the results are preliminary...)

Would it be OK if I changed it?

 

[Kati]

I concur Robin, it should read donors

 

[Esther12]

Sure - I'd just noticed that myself. Thanks.

 

[_Kim_]

Sure - I'd just noticed that myself. Thanks.

I changed the title, but there are so many other important aspects to this report besides the 0.1% XMRV positivity in blood donors.

I think the title should reflect the whole abstract:
"XMRV: Examination of Viral Kinetics, Tissue Tropism, and Serological Markers of Infection"

 

[George]

Preliminary results showed evidence of detectable reactivity to all 3 antigens in a low proportion (~0.1%) of US blood donors.

umm, guys what they are trying to say is that a very low proportion of blood samples showed Antibodies, what would equal less than 0.1% of their blood donors. This virus seems to have the ability to sneak by the immune system without creating an antibody response. That they have found. for now. we'll see.

 

[Esther12]

I changed the title, but there are so many other important aspects to this report besides the 0.1% XMRV positivity in blood donors.

I think the title should reflect the whole abstract:
"XMRV: Examination of Viral Kinetics, Tissue Tropism, and Serological Markers of Infection"

I'm happy for you to change to title to whatever you think's best. I just chose the part which stood out most to me.

 

[acer2000]

The study of blood donors is somewhat biased. Even though there are no tests for XMRV, the screening process should effectively exclude people with symptoms of CFS or recent major illness and also people deemed generally "high risk" such as risky sexual behavoir, sharing needles, gay men - regardless of their sexual practices, certain travel histories, etc... Apparently some people try to donate anyways and/or lie on the questionaire, and the screening process isn't perfect. Even controlling for the screening process, not everyone donates blood - the donors are probably skewed to certain demographics. Plus, they can't check every unit of blood, they only checked a subset of for ths study. Saying there is a 0.1% hit rate is better than saying it doesn't exist - but it isn't neccesarily representative of the rate of infection in the general population. I suspect the rate of infection is much higher than the percentage of infection that shows up in blood screening studies.

 

[George]

I suspect that an Antibody test isn't going to work, very well.

 

[Robin]

umm, guys what they are trying to say is that a very low proportion of blood samples showed Antibodies, what would equal less than 0.1% of their blood donors. This virus seems to have the ability to sneak by the immune system without creating an antibody response. That they have found. for now. we'll see.

So....only .1% of donors would show antibodies if they had an infection? Not.... .1% of blood supply might be infected?

i'm confused! help!

 

[Esther12]

Well - it seems I rather misunderstood the abstract for this paper. Lucky I posted it here for other to comment!

 

[Gerwyn]

Gerwyn,

Maybe I'm not getting it, but wouldn't CFS patients, by definition, have had to have been "infected" (if that's what happened), and have developed symptoms, for at least 6 months to even get a diagnosis of CFS?

Are you confusing "infection" with "culturing" the virus for purposes of testing? I don't think the abstract mentioned anything about culturing the blood. (I realize my terminology is probably off. I have trouble following all this.) Just looks to me like you're comparing two different things.

​

They used a technique called transfection using PCR products into cells and expected virus which would produce an immune response after 18 hours
This is analagous to infection In how long after an "infection" can you find viable virus at detectable titres.The researchers in the primate study had the sense to wait 144 days after their" transfection"

or deliberate infection proceedure

 

[Gerwyn]

umm, guys what they are trying to say is that a very low proportion of blood samples showed Antibodies, what would equal less than 0.1% of their blood donors. This virus seems to have the ability to sneak by the immune system without creating an antibody response. That they have found. for now. we'll see.

From what i,ve read the prevelance of antibodies to xmrv in healthy blood is about 3 in 2700 samples.The prevelance in US doners seems much higher than that

 

[FernRhizome]

Could someone direct me to where the original text came from that mentions the .1% in blood donors? I don't see that in the abstract. Would love to know what paper or abstract that came from. Thanks. ~Fern

 

[Lesley]

Fern,

It's the last sentence under "Results" in the abstract.
:Retro smile:

 

[FernRhizome]

Thank you Lesley!!!! It's so easy to miss a sentence with brain fog! I guess it's so low because so few of us can give blood. ~Fern