Although immune cells are largely locked out of the central nervous system, they can still keep a close watch on cellular trash being removed from the brain to scan for infection or injury. And conversely, immune cells also send signals of their own that influence brain function.
The microbial communities living in the gastrointestinal tracts of newborn babies have changed a lot in the past century, with beneficial Bifidobacterium species becoming far less prominent, especially among formula-fed infants. Understanding why that is has helped researchers develop probiotics that can restore a more historic microbiome.
In the mid-1990s, more than 40 gray wolves were released into Yellowstone National Park, and in the years and decades that followed, researchers attributed the ecosystem’s rejuvenation to the reintroduction of the apex predators. But the nature of the wolves’ influence is still debated. Now, efforts are ongoing to repeat the experiment and try to get ...