XMRV is dead, but what about the antibodies?

[FancyMyBlood]

I made this post in another topic, but because of the importance I think this deserves an own topic to increase exposure and the chance for answers.

Unfortunately they didn't post my question either (Science chat). While I now firmly believe the XMRV connection is dead, I still can't close the chapter for myself until it's answered. I've already asked it to prof. Racaniello on his virology blog after the Singh or the Levy/Coffin study, but I didn't get a response.

In this interview (http://blogs.wsj.com/health/2011/05/...igue-syndrome/) prof. Racaniello states that "He says that other viruses have proteins that are highly related to XMRV proteins. If the patients then test positive for antibodies, it looks like they have antibodies to XMRV but they are not specific to that virus."

To me it sounds he's suggesting there is another virus causing the antibody response. But how can we find out which virus it is? And if it's not a virus, what can explain the antibody reponse?

 

[currer]

As far as I understand it, the antibody evidence stands good.

It seems Silverman constructed the "XMRV" clone incorrectly from the viral fragments available to him.

In fact the HGRVs infecting people with ME are not the XMRV strain which explains why no-one could find XMRV in the negative papers.

Mikovits always stated that she was finding a wide range of MLVs in her patients, as did LO and Alter, but this was ignored and research focused on the XMRV construct only.

Patients have antibodies to infecting HGRVs which still have not been sequenced (the original attempt at sequencing by Silverman which resulted in XMRV being a mistake)

Patient antibodies show that they are infected by a HGRV.
This has now got to be sequenced so we have a complete genetic sequence to use in PCR research. If the sequence is wrong, as the sequence called XMRV was, the PCR cannot find it.


Thye antibody results in Lombardi et al show that ME patients have antibodies to a HGRV/MLV like virus

This shows the importance of classical retrovirological techniques in research, which use several mutually reinforcing methods of revealing viral infection in host cells. PCR alone is useless if the primers are set to mistaken or false sequences.
Unfortunately, because PCR takes less skill to do, it has become the preferred option for recently trained virologists.
The last year has amply displayed the pitfalls of this disregard for earlier basic virological skills.

 

[Bob]

As far as I understand it, the antibody evidence stands good.

It seems Silverman constructed the "XMRV" clone incorrectly from the viral fragments available to him.

In fact the HGRVs infecting people with ME are not the XMRV strain which explains why no-one could find XMRV in the negative papers.

Mikovits always stated that she was finding a wide range of MLVs in her patients, as did LO and Alter, but this was ignored and research focused on the XMRV construct only.

Patients have antibodies to infecting HGRVs which still have not been sequenced (the original attempt at sequencing by Silverman which resulted in XMRV being a mistake)

Patient antibodies show that they are infected by a HGRV.
This has now got to be sequenced so we have a complete genetic sequence to use in PCR research. If the sequence is wrong, as the sequence called XMRV was, the PCR cannot find it.


Thye antibody results in Lombardi et al show that ME patients have antibodies to a HGRV/MLV like virus

This shows the importance of classical retrovirological techniques in research, which use several mutually reinforcing methods of revealing viral infection in host cells. PCR alone is useless if the primers are set to mistaken or false sequences.
Unfortunately, because PCR takes less skill to do, it has become the preferred option for recently trained virologists.
The last year has amply displayed the pitfalls of this disregard for earlier basic virological skills.

Thanks currer. That's very interesting.

Basically, it looks like they have to start all the research from scratch.

Some of the results are clearly demonstrating something, aren't they, even if we don't know exactly what yet.

The antibody results in themselves could be used as a biomarker, so they are very important.

But the whole thing is an unfortunate mess.

I hope the WPI, and others, can get the funding that they need to fully explore their research.

 

[Jemal]

Thanks currer. That's very interesting.

Basically, it looks like they have to start all the research from scratch.

And you call that interesting?

But I agree, the WPI and others need to do a lot more research.

 

[VillageLife]

So are the monkey studies all invalid !? I guess yes. But if these new XMRVs act similar to the old XMRV I guess they are valid.

We will need a lot of work on these new XMRVs to see if they act the same as the old XMRV - do they turn on with hormones and stress are they in prostate cancer?

 

[VillageLife]

So the old XMRV was discovered 5 years ago.

It's going to take a few years for the new ones then.

 

[omerbasket]

The way I see it, the problem is that the WPI and the NCI found those antibodies in many of the controls, and there was no statistically significant difference between the number of controls that were found to be positive by serology and the number of patients that were found to be positive by this method (meaning that whatever virus it is, it seems that it's not unique to patients).

However, I already saw in the other forum that Gerwyn wrote something which I guess might explain, or at least patrially explain, why the serology results came back as they did (and wouldn't have if things were done as they were in the Lombardi et al. 2009 study):

The wpi assay alone depended on activated PMBCs( B and T cells) they need to be activated to increase in number so that the provirus integrated into their DNA also nicreases in concentration so that it can be detected

You cant activate or culture dead B and T cells without being treated with preservative such as trizol they would have been as dead as a doornail
the WPI was the only one in this part of the experiment which had PCR test known to be able to detect a grv in a clinically infected person

for some reason lo used a PCR test which had failed before ( he must be mortified)


the serology assays relied on culture so they would not have worked either what a mess!!

 

[currer]

Hi Omer,

Yes Ive just noticed the lack of consistency in the serology results.

So this isnt just a PCR problem. I cant really edit my previous post because it has been quoted, so Im just adding this post to acknowledge this problem

 

[soulfeast]

I have not been in the loop for a while.. what's going on? I tested pos PCR but neg antibody.

 

[magnetronnie]

Don't quote me on this one, but I believe the antibodies discovered by Lombardi et al. were against SFFV virus envelop and not specifically for XMRV or HGRVs in general. So a lot of mouse viruses (or contamination by mouse viruses) are candidates to explain these findings.

Maybe another possibilty is that antibodies formed in vitro. I always assumed they couldn't, but I recently found some studies that show antibody formation continues even in vitro. So I was thinking, maybe the blood samples got contaminated by XMRV and the white blood cells produced antibodies against XMRV. That would explain the results from the BWG I guess?