ELEVATED LEVELS OF THE COMPLEMENT COMPONENTS-C3 AND FACTOR-B IN VENTRICULAR CEREBROSPINAL-FLUID OF PATIENTS WITH TRAUMATIC BRAIN INJURY

Immunological events occurring in the central nervous system (CNS) as a result of head trauma are largely unexplored. We report here that th e levels of the alternative pathway complement proteins C3 and factor B are elevated in the cerebrospinal fluid (CSF) of head-injured patien ts. C3 and factor B indices suggest that changes in C3 and factor B le vels in CSF are most likely due to altered blood-brain barrier integri ty and not to intrathecal synthesis. These data demonstrate, for the f irst time, elevated levels of complement proteins in CSF of patients w ith severe traumatic brain injury. Elevated complement levels in brain injury may contribute to secondary damage.