February 25, 2021
ROCKVILLE, MD – The Zika outbreak of 2015 and 2016 is having lasting impacts on children whose mothers became infected with the virus while they were pregnant. Though the numbers of Zika virus infections have dropped, which scientists speculate may be due to herd immunity in some areas, there is still potential for future outbreaks. To prevent such outbreaks, scientists want to understand how the immune system recognizes Zika virus, in hopes of developing vaccines against it. Shannon Esswein, a graduate student, and Pamela Bjorkman, a professor, at the California Institute of Technology, have new insights on how the body’s antibodies attach to Zika virus. Esswein will present the work, which was published in PNAS, on Thursday, February 25 at the 65th Biophysical Society Annual Meeting.
Zika virus is a kind of flavivirus, and other flavivirus family members include dengue, West Nile, and yellow fever virus. To protect against these and other pathogens, “we have the ability to make a huge diversity of antibodies, and if we get infected or vaccinated, those antibodies recognize the pathogen,” Esswein said. But sometimes when the body mounts an immune response against a flavivirus, there is concern that this response could make the person sicker if they get infected a second time. Called antibody-dependent enhancement (ADE), this happens when the antibodies stick to the outside of the virus without blocking its ability to infect cells, which can inadvertently help the virus infect more cells by allowing it enter cells that the antibodies stick to.