Diseases with the Epstein-Barr virus (EBV) are among the most common viral infections in humans. The initial infection causes mononucleosis in some children and young adults, which is characterized by symptoms such as fever, swollen lymph nodes and exhaustion that sometimes lasts for months. Its trigger was previously unclear. Researchers at MedUni Vienna have now discovered a cause and thus a new possible target for the development of vaccines.
Scientists have not yet been able to explain why EBV causes glandular fever in some infected people and not in others. The team led by Elisabeth Puchhammer-Stöckl, head of the Center for Virology, has now identified a specific immune response once morest the Epstein-Barr virus as the cause. The study results were published in the renowned journal “Blood” of the American Society of Hematology.
The multiplication of EBV in the body is combated by an antiviral immune response, primarily using T cells. In addition to the classic T cell mechanisms, there is also a “non-classic” T cell response that leads to the destruction of virus-infected cells. Here certain EBV components (peptides) are presented to the T cells by a specific molecule (HLA-E) that is located on the surface of EBV-infected cells. Due to a gene variation (HLA-E*0103/0103), more HLA-E molecules are naturally present on cells in regarding a third of the population.
Looking for long-lasting protection
“In our investigations, we found that people with the HLA-E*0103/0103 gene variant develop glandular fever much less frequently than people who carry another HLA-E variant. As our laboratory experiments showed, this gene variant was also associated with a strong EBV-specific immune response,” explained first author Hannes Vietzen. “Since this immune response was measurable years following initial EBV infection and provides long-lasting protection once morest re-infection with EBV, it may be worth targeting this mechanism for future vaccine development.”
“The combination of unfavorable HLA-E gene variants and certain EBV peptides also seems to play an important role in the development of EBV-associated lymph node cancer in immunosuppressed patients following transplantation,” reported Vietzen. An analysis of the EBV strains may be helpful in order to be able to identify high-risk patients at an early stage and treat them in good time. (apa)
