Foremost Virus Hunter Finds Biomarkers, Few Viruses in Big Chronic Fatigue Syndrome Study
A Surprise Presentation
We will publish data very soon on biomarkers of cytokines. Our evidence now suggests there is ongoing stimulus to the immune system. Dr. Ian Lipkin
You don't usually get study results in talks like the one put on by the CDC yesterday but this time Dr. Ian Lipkin spilled the beans on the results from the big pathogen studies sponsored by the Chronic Fatigue Initiative (n=200) and Dr. Montoya (400). (From notes taken on the talk)
Virus Study Results Revealed
Viruses have always been the elephant in the room in ME/CFS; everybody has wondered about them but until the Chronic Fatigue Initiative came along, few major studies had been done. This landmark study, using the one of the top virus hunters in the world and epidemiologist Mady Hornig, and containing hundreds of patients from ME/CFS specialists (Dr. Peterson, Klimas, Montoya, Levine, etc.) from across the country, sets a benchmark for pathogen research in ME/CFS.A special feature of the study involved Simmaron Research's spinal fluid samples. Called a 'unique resource' earlier by Dr. Mady Hornig, these samples allowed the researchers to get as close to the brain - long thought to be a key area in chronic fatigue syndrome - as they could. And the spinal fluid results were spectacular.
The Studies
The studies looked at both pathogen presence and the immune response in hundreds of people with chronic fatigue syndrome.
Pathogens
- First Phase - Screens for 18 specific pathogens already implicated in ME/CFS (herpesviruses, HTLV, enteroviruses, West Nile Virus, etc.) were done on blood from Montoya's patients and the CFI's group (Dr's Peterson, Klimas, Bateman, Levine, etc.). Dr. Lipkin was looking for the virus, not a indication it was present, but the virus itself. Any finding of a virus in the blood would indicate it was active. The same screen was done on Dr. Peterson's sixty spinal fluid samples.
- Second Phase - The second phase involved sequencing all the DNA/RNA in the blood to identify known and unknown viruses. Dr. Lipkin's lab has been able to identify hundreds of novel viruses using this technique.
- Third Phase - Any finds in the second phase are confirmed/denied by more accurate testing.
Immune Response
A 'multiplexed immunoassay' looked at 50 proteins associated with immune activation/inflammation and oxidative stress.
Active Viruses Strike Out
Four of the 285 ME/CFS blood samples tested positive for HHV-6B. One of the sixty spinal fluid samples tested positive for a virus (HHV-6B). None of the other viruses commonly associated with ME/CFS (Epstein Barr-Virus, enteroviruses, the cytomegalovirus, etc.) commonly associated with ME/CFS showed up in the first pathogen screen.The high throughput screening designed to look for any viruses including novel viruses drew a blank as well. Dr. Lipkin was confident in his results stating his lab had found over 500 new viruses using this technique.The news - that fewer than 2% of patients with infectious onset - tested positive for viruses in the blood was stunning but not without precedent. Dr. Unger reported earlier that the first stage of the CDC's BSRI pathogen study drew a blank. A spinal fluid study also turned up no viruses, and PCR analyses done by the Dubbo group were unable to find evidence of a virus in their post-infectious cohort.With two large sample sets turning up negative in the lab of one of most acclaimed virus hunters on the planet, it's probably safe to say that the hunt for an virus in the blood of people with ME/CFS is over.(Lipkin did report 85% of pooled samples possibly showed evidence of a retrovirus but believes they will not be related to CFS. He also dismissed earlier rumors that a novel infectious agent had been found.)
Infectious Agent Still Proposed
That doesn't mean an infectious agent is not involved. In fact, Dr. Lipkin stated he didn't doubt that an infectious agent was involved. He didn't say where and he didn't say it was still present. His allusion to the importance of finding evidence of a past infection ("researching the shadows") suggested he could be leaning to the 'hit and run' hypothesis where a pathogen sweeps in, does its damage, and then gets removed by the immune system.The Dubbo studies' finding that high cytokine levels early in the infection were strongly associated with getting ME/CFS later on suggested an overactive immune system may have a blown a few fuses somewhere.On the other hand, Dr. Lipkin specifically alluded to an 'agent' driving the immune activation he found in both the blood and spinal fluid of ME/CFS patients (but not the healthy controls).
Localized Infections Still Appear to Be a Possibility
Dr. Lipkin didn't discuss this possibility. The blood is the most convenient place to search for an virus and active viruses usually do travel through the blood but central nervous system or localized infections may not show up in the blood or the spinal fluid.Some evidence of localized infections in the gastrointestinal tract has been found in ME/CFS. A De Merileir team found evidence of HHV-6, EBV and parvovirus B-19 in 15-40% of gut biopsies. Eighty-two percent of stomach biopsies tested positive for a protein associated with enteroviruses in Dr. Chia's 2008 study. Dr. Chia reports enteroviruses are found much more readily in the stomach than the blood (but he is able to find it in the blood). No enterviruses were found in the present study.Vanelzakker proposes that a localized vagal nerve infection is causing the symptoms in ME/CFS. It's not clear what these results mean for Dr. Lerner's theory that an aborted EBV infection is spilling viral proteins into the blood that are sparking an immune result.
The Three Year Breakpoint
Data suggests there may be substantial differences in biomarkers in people with less than 3 years of disease and those with more than 3 years of disease. Dr. Lipkin
Echoing similar recent findings from the Broderick/ Klimas team at NSU, Dr. Lipkin stated the immune system in 'newbies' (patients with recent onset), and patients with a longer case of ME/CFS was different. Dr. Lipkin's ability to independently differentiate 'newer' from 'older' patients using cytokine results is pivotal, and points to the central and progressive role the immune may play in this disorder.With Broderick suggesting that two distinct illnesses emerge over time, and Lipkin proposing treatment options should reflect illness duration, it was clear these changes were significant indeed.Natelson, on very different track, is finding changes over time as well with more POTS in his adolescents and a different kind of orthostatic intolerance in older patients. Studies are underway to understand why this might be so.
An Early Allergic Response
Allergy is not usually mentioned in association with ME/CFS but eosinophils and other markers suggested to Dr. Lipkin that the allergic response was enhanced in ME/CFS early on. The cast of immune characters Lipkin's biomarker search fleshed out was refreshingly familiar with IL-17, IL-2, IL-8 and TNF-a leading the list.No mention, interestingly, was made of autoimmunity, but Lipkin, pointing at the high IL-17 levels in the newbies, embraced the idea (only after further validation) of using immunomodulators in some ME/CFS patients to turn down the fire in the immune system. Immunomodulators exist now, he said, that can bring that IL-17 cytokine down. (He stressed, however, that there is not enough research to start using them on patients.)The spinal fluid, interestingly enough, showed a very different pattern. It showed a consistent profile of immunological dysregulation in CFS, regardless of duration of illness. Dr. Lipkin identified increased IL-10 and IL-13 levels suggesting enhanced Th2 activation and increased IL-1B, IL-5 and IL-17 suggesting Th1 (proinflammatory) activation. Dr. Lipkin was obviously intrigued by the differences in cytokine findings between spinal fluid and blood.
A Focus on the Gut
I think the gut microbiome is going to be where the action is (in chronic fatigue syndrome). Dr. Ian Lipkin
Lipkin's prime focus at this point is the gut and fecal matter. He believes the gut microbiome is going to play a, perhaps the key role in ME/CFS.The Hornig/Lipkin team has had considerable experience with the gut microbiome. They've been successful finding gut abnormalities in autism, a disorder that shares some intriguing commonalities with ME/CFS, including low natural killer cell functioning. Noting that the gut can modulate immune functioning, not just in the gut, but across the body he asserted the gut is going to be 'where the action is' in ME/CFS.Unfortunately, the fecal samples originally collected didn't provide enough material for analysis so they're restarting that part of the study.Even more unfortunately, characterizing the bacteria in fecal matter is extremely expensive and with Lipkin, with just 10% of the money needed to do the job, evidenced considerable frustration at having his hands tied by lack of money.Stating that he was not pointing fingers, he then proceeded to point them everywhere: at federal politics of funding, at NIH budget cuts, and at the paucity of research funding in our field. As at his last public talk, he urged patients to get active and enlist their congressman in their cause. Oddly enough, he also said Dr. Fauci, long considered a kind of ME/CFS nemesis by patients, was supportive of more work in this area.Reiterating his belief that chronic fatigue syndrome has pathophysiological roots, Lipkin noted his history with it. Dr. Lipkin's 1999 ME/CFS study did not find the virus he was researching but it did find a great deal of immune (polyclonal B-cell) activation, a pattern that was recently repeated when he didn't find XMRV but was impressed by the evidence of immune activation he did find.
Next Up
Lipkin, in close collaboration with his ME/CFS experts, Dr. Peterson, Dr. Montoya. Dr. Klimas, Dr. Komaroff, etc. is following these results with deep sequencing of samples, completion of fecal matter analysis and larger studies to confirm and deepen the understanding of cytokines as biomarkers. Protein analysis was not mentioned but it was part of the original project. Tracking down evidence of past infection was also on the agenda.
Conclusion
The Chronic Fatigue Initiative's pathogen study set a benchmark for rigor and size in the ME/CFS research field, not the least because of Dr. Lipkin's leadership. Surprisingly few viruses were found in the blood of ME/CFS patients, yet Lipkin asserted that an infectious agent was likely driving the immune activation he found in the blood and spinal samples. Cytokine analyses of the blood suggested a different pattern of immune dysregulation was present in newer onset patients (<3 years) and patients with a longer duration of illness.Dr. Lipkin believes the "primary cause is likely to be an infectious agent" and the gut microbiome is where 'the action' will be in ME/CFS.