One of the challenges in fighting infectious disease is that researchers cannot watch individual pathogens inside living animals. Did the drug kill the microbes? Did pathogens escape to the brain? Now imaging techniques are providing answers by following microbes on the move.
An approach described in PLoS Pathogens in July allowed British researchers to peer inside fruit fly embryos to track fluorescent versions of the bacterium Photorhabdus asymbiotica. Using high-resolution confocal microscopy, the scientists discovered that the microorganism thwarts the immune system by emitting a toxin and immobilizing hemocytes, cells that would normally kill it. Meanwhile, at the Scripps Research Institute and New York University, researchers looked inside mouse skulls to learn how viral meningitis can cause seizure. By recording moving images of the cells using two-photon microscopy, they discovered an unexpected class of immune cells that damage vessels in the brain. Also at NYU, researchers are capturing images of fluorescent Lyme disease spirochetes moving into the brain, hoping to chart infection and document the moment of cure.