GFAP and injury: Significantly increased numbers of GFAP-positive astroglial cells could be detected adjacent to a cortical contusion from 1 day up to 4 weeks after human brain injury [89], and thus, the quantity of astrocytes, indentified by GFAP immnuostaining, might be closely related to the level of blast exposure [42] and the severity of posttraumatic brain injury [90].