Experimental mAbs show promise against Epstein-Barr virus

Researchers from National Institute of Allergy and Infectious Diseases (NIAID), in collaboration with researchers from Walter Reed Army Institute of Research, US, investigated a panel of monoclonal antibodies (mAbs) targeting different sites of the Epstein-Barr virus (EBV). They were tested in human cells in a laboratory setting, with the results published in the journal Immunity.

The mAbs blocked infection in the human cells, and even one of the experimental mAbs provided nearly complete protection against EBV infection and lymphoma when tested in mice.

EBV is one of the most common human viruses. After an infection, the virus becomes dormant in the body but may reactivate in some cases.

It is the primary cause of infectious mononucleosis and is associated with certain cancers, including Hodgkin lymphoma, and autoimmune diseases, such as multiple sclerosis. People with weakened immune systems are more likely than immunocompetent people, to develop severe symptoms and complications from EBV infection.

The researchers developed several investigational mAbs that targeted two key proteins: gH and gL. The two proteins facilitate EBV fusion with human cells and cause infection. When tested in the laboratory setting, the investigational mAbs prevented EBV infection of human B cells and epithelial cells,which line the throat at the initial site of EBV infection.

By analysing the structure of the mAbs and their two surface proteins using X-ray crystallography and advanced microscopy, the researchers identified multiple sites of vulnerability on the virus to target. When tested in mice, one of the experimental mAbs (mAb 769B10) provided almost complete protection against EBV infection when given. The mAb also protected all mice tested from EBV lymphoma. 

Currently, there is no licensed vaccine to protect against the virus. Yet, the findings highlight viable EBV vaccine targets and the potential for experimental mAbs to be used alone or in combination to treat EBV infection in immunocompromised patients. The researchers note that they have planned further research with mAb 769B10.