In 2015, an outbreak of Zika virus triggered an epidemic in the Americas. People infected with Zika, typically via a mosquito bite, may have mild symptoms, but if the person is pregnant, it can lead to severe birth defects. How does the virus pass from mother to fetus?
A team of researchers from Penn State and Baylor College of Medicine found that the Zika virus builds tiny tunnels, called tunneling nanotubes, to stealthily transport material needed to infect nearby cells, including in placental cells. It's one way the virus crosses the placental barrier, transmitting from mother to fetus during pregnancy without raising alarm in the immune system. The team also demonstrated, for the first time, that one specific Zika protein - non-structural protein 1 (NS1) - is responsible for the formation of the nanotubes.
The findings, published in Nature Communications, are a first step toward identifying measures to prevent infection and potential targets for antiviral therapies. This study was funded by a grant from the U.S. National Institute of Allergy and Infectious Diseases, totaling nearly $4 million, received in 2024.
"For Zika to infect newborn babies, it means the virus has to pass from the mother across the placental barrier, which usually only allows select molecules to pass through, like nutrients and antibodies," said Anoop Narayanan, research professor of biochemistry and molecular biology at Penn State and senior author of the paper. "With this new discovery, we may be able to find a way in which we can stop the viruses from going from mother to fetus and control its spread."
