Medical science has not yet been able to explain why Epstein-Barr virus triggers infectious mononucleosis (IM) in some people with primary infection but not in others. But now, a research team led by Elisabeth Bukhammer-Stökl, head of the Center for Virology at Medoni Vienna, has identified a specific immune response to the virus as a cause, and as a potential target for vaccine development. The results were recently published in the Journal of the American Society of Hematology blood.
T cells normally combat the spread of Epstein-Barr virus (EBV) in humans as part of the antiviral immune response. Through this important mechanism, some EBV components (peptides) are presented to T cells by a specific molecule (HLA-E), which is present on the surface of EBV-infected cells. This triggers an unconventional T-cell response that destroys infected cells. Due to the genetic variation (HLA-E*0103/0103), about a third of the population naturally have more HLA-E molecules on EBV-infected cells.
A recently published study showed that the risk of myocardial infarction after first infection with Epstein-Barr virus is strongly dependent on the immune response specific to EBV. The investigation was carried out by a research team led by Elisabeth Butchammer-Stökl, Head of the Center for Virology at Medony Vienna, in collaboration with colleagues from the Department of Thoracic Surgery and the Department of Tertiary Medicine at Medony Vienna, as well as researchers from Erasmus. University Medical Center Rotterdam. “Our research revealed that people with the HLA-E*0103/0103 genetic variation have a lower risk of infectious mononucleosis than those without this variation. Our laboratory experiments showed that this genetic variation is very clearly linked,” explained Hannes Witzen of the Center for Disease Control and Prevention. Medoni Vienna of Virology, first author of the study, found that EBV virus specific–non-classical–immune response.
Preventive and diagnostic possibilities
Of all the viral infections in humans, EBV is one of the most common. Upon initial infection, the virus causes myalgia in some children and young adults; This disease is characterized by non-specific symptoms, such as fever, in addition to fatigue, which in some cases can last for several months. Until now, it was not clear why first-time EBV infection leads to muscle infection in a minority of people, while most show no symptoms at all. The researchers didn’t just identify the EBV-specific immune response as the cause of this phenomenon — the response could also be a potential target for research into preventive measures: “This immune response was still measurable years after the initial EBV infection and is generally providing , looking to the future: “Long-term protection against reinfection with Epstein-Barr, so it may be beneficial to focus our attention on this mechanism with a view to developing new vaccines in the future.”
Another finding from the study could also open up new diagnostic options: “The combination of unfavorable HLA-E genetic variation with EBV peptides appears to play an important role in the development of EBV-associated lymphomas in transplant recipients,” Hannes Vietzen commented. “Analysis of the EBV strains found in these patients can be useful for identifying high-risk patients at an early stage and treating them in a timely manner.”