virus and MS
One of my interests
is the role of Epstein-Barr virus (EBV) in causing MS. Infection with this common virus has been linked to MS, but it
is not clear how the virus might cause the disease. We have several projects focused on various aspects of Epstein-Barr
virus and MS, some of which are completed and published.
Work in progress
Does EBV cause MS activity? We are testing
whether EBV reactivation is what causes disease activity in MS. We measure changes in the amount of EBV in the blood
and changes in the immune response to EBV, and compare that to disease activity on MRI. This study requires a lot of
dedication from the participants, since we have blood draws every 2 weeks and MRI scans every 4 weeks for a total of 16 weeks.
We are aiming to recruit 20 subjects for this study in 2012 and 2013. We are looking for people with recently diagnosed
MS and active lesions on a recent MRI scan to participate in this study.
Is the antibody response
to EBV altered in MS? Antibodies or immunoglobulins are proteins made by the B cells of the immune system that
specifically bind to a certain virus, bacteria, or protein. They are important for controlling infections, and have
a lot of different functions. We measured several different antibodies to EBV in MS and controls. We found that
antibodies to the EBV nuclear antigen are increased in MS, as have several other investigators. We also looked at neutralizing
antibodies, which bind to EBV and keep it from infecting new cells. These weren't any different in MS.
Is the immune response
to EBV defective in MS? This was a more complicated study. We first infected blood cells with EBV, and
grew them in culture until we had a lot of them. Then we got a second blood sample from the same person, and measured
how the different types of cells react against the virus. The CD8 cells didn't seem to be as effective at killing virus-infected
cells in MS, but other aspects of the immune response were intact. The differences between the MS group and the controls
were suggestive, but not significant.
people with MS have a worse infection with EBV? We measured how much virus was present in the blood of people
with MS and a group of matched controls. The amount of virus in the blood varies a lot in both MS and controls, but
there wasn't any difference in the two. We did find that EBV in the blood tended to increase during relapses, and especially
before relapses. This is consistent with the idea that maybe reactivation of EBV provokes MS relapses.
Lindsey JW, Hatfield LM, Crawford MP, Patel S. Quantitative PCR for Epstein-Barr virus DNA and RNA in
multiple sclerosis. Mult Scler2009 Feb;15(2):153-8.
Do people with MS
have a different strain of EBV? After the initial infection, EBV stays in a latent state in the blood cells,
and you can determine what strain of virus is present in the blood. We did this in a group of people and found that
there was no difference in virus strain in MS.
Lindsey JW, Patel S, Zou
J. Epstein-Barr virus genotypes in multiple sclerosis. Acta Neurol Scand2008 Feb;117(2):141-4.