ANN ARBOR--An injection of nanoparticles can prevent the body's immune system from overreacting to trauma, potentially preventing some spinal cord injuries from resulting in paralysis.
The approach was demonstrated in mice at the University of Michigan, with the nanoparticles enhancing healing by reprogramming the aggressive immune cells--call it an "EpiPen" for trauma to the central nervous system, which includes the brain and spinal cord.
In a normal injury, immune cells infiltrate the damaged area and clear debris to initiate the regenerative process.
The central nervous system, however, is usually walled off from the rough-and-tumble of immune activity by the blood-brain barrier.
A spinal cord injury breaks that barrier, letting in overzealous immune cells that create too much inflammation for the delicate neural tissues.
That leads to the rapid death of neurons, damage to the insulating sheaths around nerve fibers that allow them to send signals, and the formation of a scar that blocks the regeneration of the spinal cord's nerve cells.