J. Exp. Med: breakthrough! Scientists found that brain cells responsible for clearing damaged neurons

June 26, 2018 / bioun / - researchers from the University of Virginia (UVA) School of Medicine recently found that microglia, a special immune cell in the brain, plays a key role in the process of clearing damaged tissues after brain injury Relevant research results were recently published in Journal of experimental medicine, entitled "national integrity and complement control synaptic material clearance by microglia after CNS injury”。 This study shows that microglia can phagocytize the remnant of damaged neurons, which can prevent damage from spreading to adjacent normal neurons, thus avoiding more serious neurodegeneration Source: Norris et al., 2018 dead cells or dying cells in every tissue of the body must be removed as soon as possible to prevent inflammation, which will cause further death of adjacent cells This process is accomplished by specialized immune cells that can phagocytize and digest the remains of cells, i.e phagocytic cells But so far scientists have not found the cells responsible for clearing the nerve debris after brain or spinal cord injury Jonathan Kipnis, head of the Department of UVA neuroscience, and his colleagues studied the optic nerve damage in mice, which causes retinal ganglion neurons in the distal brain to degenerate and leave behind debris The researchers found that the residue was swallowed by microglia Microglia, which mainly reside in the central nervous system, are phagocytes that can engulf bacteria and other pathogens invading the brain They also play a key role in brain development and in pruning synapses that do not fully function Microglia in the adult brain can use some of the molecules they use to identify inactive synapses or invade pathogens to identify degenerated neurons Kipnis and colleagues found that after optic nerve injury, microglia produce complement proteins to help them identify their targets The researchers studied the damage to the optic nerve in mice where microglia were unable to produce complement proteins and found that the microglia were unable to remove the residue "In the future, we hope to find out how microglia are activated in response to neurodegeneration and how they clear damaged neurons." Kipnis, director of the UVA brain immunology and neuroglial center "Knowing these mechanisms will help us enhance the ability of microglia to remove toxic residues and limit the spread of neurodegeneration after brain or spinal cord injury." Reference: Norris et al National integrity and composition control synthetic material clearance by microglia after CNS inquiry J exp med.2018 Doi: 10.1084/jem.20172244