Scientists discover protective antibodies with potential to treat West Nile virus

Researchers at the Institute for Research in Biomedicine in Switzerland have identified human monoclonal antibodies that may prevent or treat West Nile virus. According to a study published in Immunity, these antibodies, derived from patients in Serbia, could inform vaccine development and provide a path to treat related orthoflavivirus infections.

How were the protective antibodies discovered?

Davide Robbiani’s Laboratory at the Institute for Research in Biomedicine (IRB), affiliated with Università della Svizzera italiana in Bellinzona, Switzerland, led the research. The team and international collaborators analyzed blood from West Nile virus (WNV) convalescents in Serbia to study antibody immune responses.

The study identified specific monoclonal antibodies that target the virus. One antibody, W010, targets a distinct site on the virus envelope domain III, which the IRB identifies as a key surface protein for viral attachment and infection.

In laboratory tests, W010 protected mice when administered before exposure. It also provided protection when given up to five days after the mice were exposed to WNV, according to the study published in Immunity.

Did You Know? A second antibody identified in the study, W014, demonstrated broader cross-neutralization against other pathogenic orthoflaviviruses, including Usutu, Saint Louis encephalitis, Murray Valley encephalitis, and Japanese encephalitis viruses.

Why is this research significant for public health?

West Nile virus is transmitted by mosquitoes and is increasingly relevant globally and in Europe. According to the IRB, the virus can lead to death or severe brain infection.

West Nile Research

The medical community currently lacks an approved human vaccine or a specific antiviral treatment for the virus. These antibodies may address this unmet medical need by providing new prophylactic and therapeutic candidates.

Expert Insight: Samantha Carter notes that the identification of vulnerable sites on the virus envelope is a critical step. Because there is no current vaccine, finding antibodies that can work post-exposure—as seen with W010—shifts the focus from simple prevention to potential active treatment of the infection.

What may happen next in WNV treatment?

The findings define vulnerable sites on the West Nile virus that could inform the development of future vaccines. Researchers may use these antibody candidates to create new interventions for WNV.

Because antibody W014 showed cross-neutralization, this research may also guide the development of treatments for a wider group of encephalitic orthoflavivirus infections. These candidates could potentially be developed into therapies to prevent or treat multiple related viruses.

Frequently Asked Questions

How is West Nile virus transmitted?
According to the research source, West Nile virus is transmitted by mosquitoes.

What makes antibody W010 unique?
W010 recognizes a specific site on the virus envelope domain III and protected mice both before and up to five days after WNV exposure.

What other viruses could this research impact?
The study identified antibody W014, which showed cross-neutralization against the Usutu, Saint Louis encephalitis, Murray Valley encephalitis, and Japanese encephalitis viruses.

Do you think the development of cross-neutralizing antibodies is the most effective path toward treating mosquito-borne illnesses?