SAN DIEGO, CALIFORNIA—We know the menagerie of microbes in the gut has powerful effects on our health. Could some of these same bacteria be making a home in our brains? A poster presented here this week at the annual meeting of the Society for Neuroscience drew attention with high-resolution microscope images of bacteria apparently penetrating and inhabiting the cells of healthy human brains. The work is preliminary, and its authors are careful to note that their tissue samples, collected from cadavers, could have been contaminated. But to many passersby in the exhibit hall, the possibility that bacteria could directly influence processes in the brain—including, perhaps, the course of neurological disease—was exhilarating. “This is the hit of the week,” said neuroscientist Ronald McGregor of the University of California, Los Angeles, who was not involved in the work. “It’s like a whole new molecular factory [in the brain] with its own needs. … This is mind-blowing.”
https://www.sciencemag.org/news/2018/11/do-gut-bacteria-make-second-home-our-brains