BLOOD VERSUS TISSUE

4generations commented on yesterday’s post on Dr. Ila Singh's XMRV-negative ME/CFS study: 

Singh's primate study found that XMRV left the blood of the infected primates after a few weeks (6, I believe). Isn't that finding plus the finding of XMRV in prostate cancer patient tissue good enough evidence to justify a study looking for XMRV/MLV in the tissues of patients with ME/CFS?

4generations, the primate study at Emory University wasn’t Singh’s. But your point is well taken, as XMRV quickly left the blood and settled in the tissues in the macaques. In addition, in the CDC’s new XMRV study on prostate cancer this week, the three patients who tested PCR positive to XMRV in tissue had no virus in plasma by PCR or Western blot.  

If that can occur in prostate cancer, perhaps that can occur in ME/CFS as well.  Moreover, as some readers have pointed out, Dr. Kenny de Meirleir in Belgium is taking tissue samples in the gut of ME/CFS patients and finding them positive for XMRV.

DR. ILA SINGH:

She believes XMRV isn't in ME/CFS patients but that there's evidence for the retrovirus in prostate cancer

CFS Central emailed University of Utah's Dr. Ila Singh about her new XMRV study, which found no evidence of XMRV in ME/CFS patients. In 2009, Singh found evidence of the retrovirus in prostate-cancer tissue.

CFS Central:  Will you revisit your prostate-cancer XMRV findings in light of this XMRV negative CFS study?  From what you’ve learned in this latest CFS study, do you now believe that the XMRV that you found in prostate cancer is a human infection or just contamination?

Dr. Ila Singh: Prostate cancer and chronic fatigue syndrome are completely different illnesses.  I recognize that recent studies have cast doubts on the prostate cancer association as well, but there is still considerable data supporting the link to prostate cancer that cannot be easily explained by contamination. We will present some of this work at the Cold Spring Harbor meeting later this month.  But clearly more work needs to be done before that question can be settled. 

CFS Central:  Do you believe scientists should be looking for XMRV in CFS patients’ tissues instead of blood?
 

Singh: The original study by Mikovits' group reported finding XMRV only from blood.  They did not examine other tissues.  So blood is where the focus should be. Now if one found it in blood, then of course you'd be interested in finding out where else the virus is.  And then it would be interesting to look at tissues.  But looking at tissues is not trivial and not something to be attempted without good evidence of the virus being present in the body first. 

CFS Central: Did you test the new assays/methods used in the new study against any XMRV positive samples from your prostate-cancer study?

Singh: Our prostate cancer study was entirely on prostate tissues. These were archived in tissue banks in a de-identified manner, so there was no way to go back to those patients and obtain blood samples.  So, we could not test some of the new tests we developed on our material from prostate cancer patients. 

CFS Central:  In your new study it says that “2 positive controls were also included” (line 349 of your study). Were the two positive controls clones or clinical samples from prostate-cancer studies or from Mikovits’s positive CFS patients? 

Singh:  The samples from Mikovits' patients were all tested in a completely blinded fashion.  We did not know which of them were positive, so could not use them as positive controls.  But more accurately, there are no real patient 'positive controls' for XMRV.  In order to use patient samples as controls, you'd have to first be absolutely certain that these patients have XMRV.  How could you do that right now?  So we used what you call a 'clone' for our PCR studies.  But remember, this clone was isolated from a patient (a prostate cancer patient).  And this is over 99% identical to the isolates from CFS patients described in Lombardi et al.  For the viral culture studies, we used very small amounts of titrated virus that was grown in the lab as positive controls. And all of these positive controls were always positive. 

CFS Central:  You grew XMRV in the prostate-cancer cell line LNCaP and the breast-cancer cell line MCF-7 in your study “Raltegravir is a potent inhibitor of XMRV, a virus implicated in prostate cancer and chronic fatigue syndrome.”  It’s unclear to me why the new study didn’t culture XMRV from those two positives. 

Singh:  Yes, we did.  And these grew just fine.  Apologies for not being clearer in the paper.  None of the patient samples tested positive, but the positive controls were always positive. 

CFS Central:  Some patients on the forums find this sentence from the new study problematic:  “We are forced to conclude that prescribing antiretroviral agents to CFS patients is insufficiently justified and potentially dangerous.”  The Science and the Alter/Lo studies have reported XMRV and related MLVs in CFS patients.  CFS patients are very ill, many for decades, and there are no approved treatments. They believe the decision to try antiretroviral drugs should be between a patient and his or her doctor. Why did you feel the need to put that statement in the study and press release? 

Singh:  The patient and their doctor did not make the decision to try antiretroviral drugs in a vacuum.  It was based on reports of finding XMRV in CFS patients.  We are now convinced that there is no XMRV in CFS patients--so the reason for starting those drugs does not exist.  And there is no good evidence for continuing to use drugs that could lead to serious side effects of liver or bone-marrow failure.

****

I wrote to Singh to ask her to clarify two of her answers:
 

CFS Central:  In your prostate-cancer study, “XMRV is present in malignant prostatic epithelium and is associated with prostate cancer, especially high-grade tumors,” you found 4 percent of healthy controls with evidence of XMRV.  If you’re finding a background rate in controls in your prostate-cancer studies, why do you think you didn’t find a background rate in CFS patients and controls?  

Singh:  Not entirely sure, but there were different assays (e.g. immunohistochemistry) and different sample types (blood vs prostate tissue).

CFS Central: To clarify one of my previous questions, beginning on line 347 of your new study, it states: “We inoculated LNCaP cells with 100 [microliters] of plasma from 31 patients and 34 healthy volunteers, and passaged the cells weekly for 6 weeks. 13 negative controls and 2 positive controls were also included. Only one culture was handled at a time to prevent any cross-contamination. After weeks 2, 4 and 6, cultures were lysed and analyzed by Western blots (Fig. 4) and by qPCR for XMRV. No XMRV protein or DNA was detected in any of the cultures. [emphasis added]  

My question is this: Is the bolded sentence correct, or did the 2 positive controls grow in these cultures and/or did the positive samples continue to test positive in culture?  If the positive controls didn’t grow or if the positives controls didn’t test positive in culture, why didn’t they?  You grew XMRV in the prostate-cancer cell line LNCaP and the breast-cancer cell line MCF-7 in your study “Raltegravir is a potent inhibitor of XMRV, a virus implicated in prostate cancer and chronic fatigue syndrome.”

Singh:  That was our poor wording in the paper (the words in bold).  All positive controls grew XMRV--as one would expect.  None of the samples from the healthy controls or CFS patients grew any virus in culture.  And of course the negative controls did not grow any XMRV.  

WHAT'S GOING ON?

I received two dozen letters from patients with more than one family member diagnosed with ME/CFS.  Most were mother and daughter, a few were mother and son, father and daughter/son, and husband and wife.

The most compelling case for an infectious ME/CFS etiology may be the family of Keith Baker, better known as bakercape on the forums. 

Now 41, Baker was 16 when he suddenly became  ill. At the time, Baker was a high-school track star and Junior Olympic metal winner in Waterville, Maine. As he testified to the Chronic Fatigue Syndrome Advisory Committee, “I was running a race and suddenly I could not put one foot in front of the other. I stopped in the middle of my race and knew something was terribly wrong with me.”

Baker was diagnosed with mono the next day and came down with chicken pox a week later. Next, his 12-year-old brother got chicken pox and mother became ill with shingles (a reactivation of the chicken pox virus) and Bell's palsy. 

When his adult sister came to visit, she too got sick.  And when Baker and his brother visited their father—his parents were divorced—his father became ill as well.  In a matter of months, everyone in the family was sick with ME/CFS.

Today Baker still has ME/CFS, as do the rest of his family. Baker hasn’t been able to run since he first became ill.  His wife is healthy, but their two children have high-functioning autism, and the elder child also has seizures. Of all the family members, Baker’s brother is the most severely affected with ME/CFS.

Genetics can’t explain this entire family coming down with ME/CFS, because Keith Baker’s parents clearly don’t share the same genetics, and neither does Baker: He’s adopted. 

Interestingly, years after becoming ill, Baker met his birth family, and no one was ill with ME/CFS.

So what happened?  Was there a common infectious agent that made the Baker family sick?  That would explain the illness that afflicted Keith Baker and his brother and mother, and perhaps his sister as well.  But Keith Baker’s father doesn’t fit neatly into that scenario as he wasn’t living in the house.  The fact that the father got sick after his sons visited indicates the illness may be contagious as well.  

No one in the family has been tested for XMRV, but they plan on getting tested this summer. 

This family’s ME/CFS history is anecdotal yes, but anecdotes shouldn’t be dismissed, especially after nearly three decades of hearing similar stories.  Over the years, there have been compelling sagas of couples or family members becoming ill with a flu, and one goes on to develop ME/CFS, while the others recover.  Sometimes the lucky family members who recover come down with ME/CFS years later, however.

I’ve also heard of couples who come down with a flu and one develops ME/CFS, while the other develops another illness, including Parkinson’s, multiple sclerosis and diabetes.

Clearly, after three decades, it’s beyond time that the CDC and the NIH study these families and establish the cause. 

NOT ENOUGH INFORMATION

My nephew is a second-year medical student at Jefferson Medical College in Philadelphia, PA.  I asked him what he's learned about ME/CFS in school, and he said only one paragraph, and this is it:

CHRONIC FATIGUE SYNDROME typically includes widespread pain as well as the history suggestive of a preceding infection, tender lymph nodes, sore throat, and low-grade fever. Fibromyalgia and chronic fatigue syndrome share the symptoms of overwhelming fatigue and problems with memory and recall, but chronic fatigue syndrome is not characterized by the 11 or more tender points of fibromyalgia.

How can future physicians treat ME/CFS effectively if all they get is a paragraph of information--and not all of it correct at that?  Many patients with ME/CFS do indeed have the fibromyalgia tender points. 

In contrast, other diseases, including lupus, multiple sclerosis and Parkinson's disease each rate a full lecture at Jefferson and about 20 pages of notes.  And the school devotes several lectures to HIV/AIDS, including one class just on drug treatments.