Front immune: the relationship between multiple sclerosis and herpesvirus

December 1, 2019 researchers at BIOON / -- Karolinska Research Institute have developed a new method to separate two common types of herpes simplex virus (HHV-6) associated with multiple sclerosis By analyzing the antibodies against the most differential proteins of herpesvirus 6a and 6b in the blood, the researchers were able to show that MS patients carry herpesvirus 6A more frequently than healthy individuals This finding was published in the journal frontiers in immunology and pointed out the role of HHV-6A in the pathogenesis of MS Multiple sclerosis, or MS, is an autoimmune disease that affects the central nervous system The cause of the disease is unclear, but a reasonable explanation is that the virus can trick the immune system into attacking the body's own tissues Human herpesvirus 6 (HHV-6) was previously associated with the development of MS, but related studies did not distinguish between 6a and 6B In this study, researchers have been able to prove that HHV-6B can cause mild diseases in children by isolating the virus from the infected population, but it is not clear whether HHV-6A is the cause of any diseases (image source: www Pixabay Com) it is estimated that up to 80% of children under 2 years old are infected with HHV-6 virus, and many have protection against this specific virus in the form of antibodies for the rest of their lives However, it is difficult to determine whether HHV-6A or B is a risk factor for MS because the two variants cannot be distinguished after infection In this study, however, researchers were able to distinguish between early proteins 1a and 1B (ie1a and ie1b) in viruses A and B by analyzing antibodies to proteins in the blood, which differ most between the two viruses "This is a major breakthrough for both MS and herpesvirus research," said Anna fogdell Hahn, associate professor of clinical neuroscience at the Karolinska Institute and one of the senior authors of the study First, it supports the idea that HHV-6A may be the cause of MS Most importantly, we are now able to use this new approach to identify these two different types of HHV-6 viruses, which we were previously unable to do " The researchers compared antibody levels in blood samples from about 8700 MS patients to the health of more than 7200 healthy people whose gender, date of birth, date of blood sample and other factors matched Ms They concluded that MS patients had a 55% higher risk of carrying anti HHV-6A protein antibodies than the control group In a subgroup of nearly 500 people who were drawn before the onset of the disease, the results showed that if they were infected with 6A virus, the risk of MS in the future would more than double The younger the person who first found the virus in their blood, the higher the risk of MS in the future On the other hand, HHV-6B has no positive correlation with MS In contrast, the level of ie1b antibody in patients with MS was lower than that in patients without Ms The researchers also used the same method to analyze antibodies to EBV, another herpesvirus associated with MS, and were able to show that individuals infected with both viruses had a higher risk of MS This suggests that several viral infections may work together to increase the risk of MS Information source: Ms linked to variant of common herpes virus original source: Elin Engdahl et al Incremental serial response against human herpesvirus 6a is associated with risk for multiple sciences Frontiers in immunology, 2019; 10 doi: 10.3389/fimmu.2019.02715