Treatment Potential of the Human Zika Antibody

Researchers have determined the structure of a human antibody bound to the Zika virus, revealing details about how the antibody interferes with the infection mechanism and thus providing findings that could aid in the development of antiviral medications. The new findings also suggest the antibody might be especially effective because a lower concentration than expected is needed to inhibit a key mechanism of infection, making it more potent than previous antibodies studied. The research was performed by a multifaceted team from Purdue University, Vanderbilt University Medical Center and the Washington University School of Medicine. Upon original isolation, findings showed that the antibody, which was isolated from a person previously infected with Zika virus, neutralizes Zika strains that belong to African, Asian and American lineages and can reduce fetal infection and death in mice. This coupled with the new findings in which researchers determined the combined three-dimensional structure of the Zika virus while attached to a key binding site on the antibody known as the antigen binding fragment, or a Fab molecule, provides the potential for a mechanism of treatment. This is based upon the analysis of binding sites on the envelope of the viral particle, consisting of 60 trimers of E proteins, which would normally require a total of 180 antibodies to bind and neutralize the particle.  This research finds that the Fab molecule can bind with a ratio of 1 molecule to 6 E proteins, making only 30 molecules necessary for neutralization vs the previous 180.  The research is an interesting approach to solving the ever prevalent Zika problem, but is not likely to end the Zika epidemic.

https://www.sciencedaily.com/releases/2017/03/170316112150.htm

-Ethan Wentworth