Brain-specific and systemic inflammatory response following repetitive concussive impact in a mouse model
Abstract
Concussion is the most common form of mild traumatic brain injury (mTBI). TBI resolution is modulated by neuroinflammation, which is augmented by the infiltration of innate immune cells from the circulation. Peripheral, myeloid immune cells not only invade neural tissues but other organs as well causing local inflammation and tissue damage, known as systemic inflammatory response syndrome. Here, I assessed the temporal and anatomical nature of the neural and systemic cellular inflammatory response to repetitive, mTBI in a 3-hit mouse model of concussion. The results showed significant microglial activity, accumulation of peripheral myeloid cells and prominent axonal damage post-injury. The peripheral immune cells emerged through the brain microvasculature and resided in the parenchyma, along the pia mater and within the ventricles. There was also evidence of systemic inflammation in the lungs as well as in the cervical spinal cords of the mTBI mice.