The same proteins that mount a potent immune response to Zika viral infection can also harm the placenta and fetal development, according to a new study.
Researchers had established that these antiviral proteins—known as type I interferons—were required to fight Zika infection in mothers. But it was not clear what role they played in providing an immune defense for the fetus.
To investigate, researchers led by Akiko Iwasaki, an immunobiologist at Yale University, studied two different types of mouse models. One type lacked the receptor for type 1 interferon altogether, and the other had only one copy of the interferon receptor gene.
Only the latter showed signs of abnormal placental development, restricted fetal growth, and death, the researchers write in Science Immunology.
The findings demonstrate that the damaging effects of the immune response to Zika virus can outweigh the benefits for fetuses, say researchers, noting that although type 1 interferon is critical to blocking replication of the virus, too much of it can be detrimental during pregnancy.
Existing drug could keep Zika from infecting fetus
The study results may have implications for other infection-related pregnancy complications and possible interventions, researchers say.
The National Institutes of Health supported the work.
Source: Yale University
