A key virus fighter is implicated in pregnancy woes
Fetal mice whose immune system revved up in response to their mom’s Zika infection died or grew poorly
KNOTTY ISSUES Placental tissue (on the right) treated with an immune protein that fights viruses developed knotty structures that resembled those associated with pregnancy complications. Untreated placental tissue (on the left) does not show these structures.
L. Yockey et al/Science Immunology 2018, Carolyn Coyne
An immune system mainstay in the fight against viruses may harm rather than help a pregnancy. In Zika-infected mice, this betrayal appears to contribute to fetal abnormalities linked to the virus, researchers report online January 5 in Science Immunology. And it could explain pregnancy complications that arise from infections with other pathogens and from autoimmune disorders.
In pregnant mice infected with Zika virus, those fetuses with a docking station, or receptor, for immune system proteins called type I interferons either died or grew more poorly compared with fetuses lacking the receptor. “The type I interferon system is one of the key mechanisms for stopping viral infections,” says Helen Lazear, a virologist at the University of North Carolina at Chapel Hill, who coauthored
