Changes in cytokine and chemokine protein expression after traumatic brain injury. The fold change protein expression of cytokines and growth factors assessed by multiplex assay decreased relative to expression in naïve controls in the combined lesion/perilesion area after injury, as summarized in the accompanying heat map. Chemokines macrophage inflammatory protein 1α (MIP-1a) and keratinocyte chemoattractant/growth-related oncogene (GRO KC) were the only proteins observed to have increased over the time course, peaking at 24 hours after injury, then decreasing. EPO, Erythropoietin; G-CSF, Granulocyte colony-stimulating factor; GM-CSF, Granulocyte-macrophage colony-stimulating factor; IFN-g, Interferon γ; IL, Interleukin; M-CSF, Macrophage colony-stimulating factor; RANTES, Regulated on activation, normal T cell expressed and secreted; TNF, Tumor necrosis factor; VEGF, Vascular endothelial growth factor. *P < 0.05.