White blood cells that gobble up cellular debris also help to heal damaged blood vessels in the brain.
Deqin Yang at Chongqing Medical University and Lingfei Luo at Southwest University, Beibei in Chongqing, China, and their co-workers used lasers to rupture blood vessels in the brains of zebrafish. They monitored the events that followed with time-lapse microscopy, and saw the immune cells, called macrophages, migrate to the damaged area. A macrophage extended projections that adhered to the broken ends of the blood vessels and pulled them together by mechanical traction. In zebrafish engineered to lack macrophages, cerebral blood vessels healed more slowly than in normal animals.
The findings expand on the known roles of macrophages in the brain, the authors say.
Immunity http://doi.org/bgrv (2016)