Sunday, 30 June 2013

EBV infection precedes to onset of MS: articles of Interest (16)

Is EBV the cause of MS? #MSBlog #MSResearch

"Having been here from the beginning I incorrectly assume that all our readers would have gone back and read all our previous posts. How could they have there are now over 2600 to read. This paper has been covered before, but it is a very important paper. It shows that in EBV-negative people who go onto to develop MS, 100% of MSers EBV positive prior to the onset of MS compared to only 36% of control subjects. Why is this important? To claim that EBV causes MS you have to show a clear temporal pattern, i.e. of being exposed to the virus before the onset of  the disease. I have also covered causation theory on this blog and this is one of the criteria you need to fulfill to claim that X causes Y, in this case EBV causes MS."

"I personally think there is enough evidence to claim that EBV causes MS. To prove this we need to show that if you prevent people being infected with the virus we prevent MS. This is easier said than done and can only really be done with an EBV vaccination study at a population level. Another option is to target EBV, with anti-viral drugs, and if this reduces MS disease activity it will support EBV as the cause of MS. This is the primary aim of the Charcot Project."

Levin et al. Primary infection with the Epstein-Barr virus and risk of multiple sclerosis. Ann Neurol. 2010 Jun;67(6):824-30.

Objective: To determine whether MS risk increases following primary infection with the Epstein-Barr virus (EBV): 

Methods: A nested case-control study, was conducted, including 305 individuals who developed MS and 610 matched controls selected among the >8 million active-duty military personnel whose serum has been stored in the Department of Defense Serum Repository. Time of EBV infection was determined by measuring antibody titers in serial serum samples collected before MS onset among cases, and on matched dates among controls. 

Results: Ten (3.3%) cases and 32 (5.2%) controls were initially EBV negative. All of the 10 EBV-negative cases became EBV positive before MS onset; in contrast, only 35.7% (n = 10) of the 28 controls with follow-up samples seroconverted (exact p value = 0.0008). 


Conclusions: The investigators' concluded that MS risk is extremely low among individuals not infected with EBV, but it increases sharply in the same individuals following EBV infection.


"Did you know that almost all highly-effective DMTs target B-cells the cells where EBV resides? I have been trying for years to get EBV biomarkers added into clinical trials to test the hypothesis that these drugs are working via an anti-EBV mechanism. Unfortunately, it seems as if Pharma are not interested in proving their drugs work in this way. Why would they? This would simply lower the hurdle and open the door for anti-viral studies.Why would we want to kill the goose that is laying the golden eggs?"

6 comments:

  1. Prof G,

    Could you give us an idea how th Charcot Project is going.

    Thanks

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  2. Is there evidence that EBV is the only virus causing MS? Could other herpes viruses like CMV and roseolo virus also be triggers?

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  3. The article above only deepens the mystery for me. How does a person sero- convert from being EBV-, to EBV+?

    I wonder what 'outlier' cohorts i.e pediatric MS cases and those diagnosed after >50? can tell us? If it is the case that we are often infected in our childhood - do the pediatric cases have higher EBV titres nudging them towards MS? Why is that some older persons appear to have dodged the nominal age range of diagnosis?

    I have a member of my group who has had two EBV tests since her diagnosis. Her neurologist has confirmed that she is not positive for EBV. She has however had CMV in the past.

    Is it possible to suggest that EBV may trigger MS 'in susceptible cases' ( e.g. genetics, T cell disregulation relating to Vitamin D etc)? Making EBV a risk factor for MS?

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  4. Re; "The article above only deepens the mystery for me. How does a person sero- convert from being EBV-, to EBV+?"

    You typically get exposed to virus in saliva, hence the term kissing disease. Another 10% get exposed sexually. Other ways are via blood and organ transplants.

    ReplyDelete

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