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IgM, and anti-EBV-EA IgG. The results showed that the onset of MS. The EBV-specific super-antigens activate
anti-EBNA IgG antibody-positive rate of the MS group CD4 T cells, which produce a cross-reaction with
+
was 25% compared with 30% in the OND group, but myelin protein through interaction with B and NK
the difference was not statistically significant. Similarly, cells. [24] In addition, EBV can directly cause acute
no statistically significant difference in the anti-EBNA myelin oligodendrocyte glycoprotein-specific cellular
IgG antibody-positive rate was found by Villegas and humoral immune responses, [25] and simultaneously
et al. [13] (6.6% in MS patients and 17.0% in OND) and activate CD8 T cells. Moreover, CD8 T cells react with
+
+
by Castellazzi et al. [14] (6.3% MS and 1.3% in OND). In B cells infected with EBV for anti-myelin associated
addition, Pohl et al. [15] showed that the anti-EBNA IgG protein antibody production. [26] However, our data are
antibody-positive rate of MS patients was 8%, similar different with the results reported by Kiriyama et al. [27]
to observations by Sargsyan et al. [16] and Jafari et al. [17] Further investigations are required to establish the
Our results support the above conclusions, but we pathogenesis of MS affected by EBV acute infections.
found the anti-EBNA IgG antibody-positive rate was
much higher than in these previous research reports. In summary, our study suggests that acute EBV infection
This difference may be explained by (1) different sample is closely associated with the pathogenesis of MS,
sizes, (2) the IFA used in our experiment which has a and that inhibition of EBV infection is beneficial to
higher sensitivity than the ELISA assay in the previous the prevention and treatment of MS. However, the
studies, and (3) the EBV infection rate in China is higher prevalence of EBV infection is high in the general
than in European and American countries with better population, but the prevalence of MS is relatively low,
sanitary conditions. In our study, the positive rate of which suggests there may be other MS causative factors,
the CSF anti-EBNA IgG antibody in the MS group was such as genetic predisposition, EBV primary infection,
lower than that in the OND group, which contrasts with age and other microbial infections. As a result, further
the reports of Jaquiéry et al. [18] and Cepok et al. [19] This studies are necessary to investigate MS pathogenesis
difference may be explained by the smaller sample size of EBV infections.
in our study and the different living environments and
the genetic susceptibility of the European and American ACKNOWLEDGEMENTS
populations as compared to the Chinese.
The work was supported by Beijing Natural Science
Positive anti-EBV-CA IgG antibodies in human CSF Foundation (Nos. 7102040, 7132060), National Natural
suggest a past history of EBV infection. Our data showed Science Foundation of China (Nos. 81041020, 81271311, and
that the positive rate of anti-EBV-CA IgG antibodies 81241039), Traditional Chinese Medicine, Beijing Technology
in MS patients was 90% compared with 95% in OND Development Fund (No. SF-2007-III-22), Beijing Excellent
patients. This observation is also supported by other Talent Foundation (No. 20071-D0300100062), the high-level
reports. [20,21] The detection of anti-EBV-EA IgG antibody technical training project funding of the Beijing Health
in CSF in our study represents either an acute or chronic System (2011-3-004) and the preferential funding scheme for
EBV infection, suggesting that EBV reproduces. This Beijing city staff to go abroad.
has also been observed in a previous study. [22] The
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