Researchers have determined the structure of human antibody bound to Zika virus. Findings show that the antibody may be particularly effective since a lower concentration than expected can inhibit an important mechanism of infection. Teams at Vanderbilt and Washington University had already isolated the antibody, but a team led by Michael Rossmann and Richard Kuhn at Purdue University has determined the structural basis for neutralization.
The antibody disrupts viral entry into cells. When Zika virus attaches to a cell's surface, a difference in pH causes Zika envelope protein trimers to expose fusion peptides. This leads to transfer of viral RNA into the cell. The human antibody prevents the pH-triggering mechanism by cross-linking the Zika envelope protein trimers and tying them up. These findings will help in development of antiviral drugs for Zika infection.