S100B: Potential biomarker for CNS insult and injury

Abstract

S100B is a calcium-binding protein expressed primarily in neuronal tissue. The protein is released from cells following neuronal injury and can be detected in serum, urine, or CSF with a simple bioassay. It has thus been widely investigated as a potential biomarker for brain injury. S100B protein levels have been shown to be significantly elevated in cases of traumatic brain injury, neonatal asphyxia, and injury secondary to cardiac arrest as well as other neurodegenerative diseases. Moreover, in severe traumatic brain injury, protein levels have been shown to be correlated with the degree of injury determined by cranial CT scans during initial patient evaluation. In mild traumatic brain injury, the use of S100B has been considered as a screening tool in conjunction with CT scans to avoid unnecessary radiation. Additionally, promising data has supported S100B in the detection of neonatal anoxic brain injury above other available screening tools. This chapter reviews current data along with its limitations regarding the use of S100B as a biomarker of neuronal injury from traumatic brain injury, neonatal asphyxia, and brain injury secondary to cardiac arrest.