During Pregnancy, a Fake ‘Infection’ Protects the Fetus
When you were a child, it seemed like an ingenious plan: Splash hot water on your face and stagger into the kitchen. Letting out a moan that could make angels cry. One touch of your flushed forehead would convince your parents. To diagnose a fever and keep you home from school. No matter how elaborately planned and performed. These theatrics probably weren’t as persuasive as you had hoped. But new research, published this summer in Cell Host & Microbe, suggests that long before birth. A similar tactic helps developing humans and other mammals put on a more convincing show
The Placenta Fakes Sick
Totary-Jain discovered the placenta’s sleight of hand by accident. She and Phone Number List her lab were researching a mega-cluster of genes. A monster she said that was expressed in the placenta. She was surprised to see that. In addition to activating genes that guide placental development. The mega-cluster had turned on the gene for interferon lambda, an immune signaling protein. Why was it active in healthy, uninfected cells? It took years for Totary-Jain and her team to zero in on an answer: The placental cells had crafted a viral look-alike, using RNA harvested from their own genomes, to dupe their immune sensors
Simmering Immunity
Immune responses can be destructive, and antiviral responses especially so. Because BVB Directory viruses are at their most dangerous when they’re already inside a cell, most immune strategies that target viral infections work in part by damaging and killing infected cells. For that reason, cells cry “Virus!” at their own risk. In most tissues, Alu sequences are highly suppressed so that they never get a chance to mimic a viral attack. And yet that is the exact scenario the placenta seems to create on purpose
