The Epstein Barr Virus (EBV) can deregulate the human immune system and cause disease
20 June 2017
BPRC researchers have previously shown that an EBV-related virus can disrupt the immune system of monkeys and can therebye cause multiple sclerosis (MS) (http://www.bprc.nl/en/article/infection-with-a-virus-related-to-epstein-barr-dysregulates-the-immune-system-of-monkeys). This work has been described previously in the Multiple Sclerosis Journal - Experimental, Translational and Clinical
In collaboration with researchers from Nottingham (UK), the BPRC scientists have studied whether the knowledge described above also applies to humans.
Normally, parts of the own body are not attacked by the immune system. However, in MS, the immune system attacks the myelin oligodendrocyte glycoprotein (MOG), a protein that forms part of the protected nerve layer. The researchers found that normal B cells, a type of immune cells, degrade this protein so that other cells of the immune system, T cells, are not activated and thus no reaction occurs.
EBV infected B cells, however, degrade the MOG protein only partially allowing T cells to be triggered to attack the MOG protein in the protecting layer around the nerves. This may cause MS. The researchers also studied the mechanism of the degradation of the partial degradation of the MOG protein. They found that survival mechanism of EBV infected B cells, called autophagy, can cause MOG protein components to be protected from degradation and thereby become visible to the immune system and thus provoke unwanted activity of T cells..
This work published in the Journal of Immunology (http://www.jimmunol.org/content/early/2017/06/07/jimmunol.1700178) shows how, compared to uninfected B cells, the presence of EBV-infected B cells in humans more readily triggers (unwanted) immune responses that can attack the own body.