C3 and Stroke: Remarkably, high mobility group box 2 (Hmgb2), tumor necrosis factor (TNF) and interleukin (IL)-11 which were pro-inflammatory factors expressed at the first day after stroke onset; cathepsin S (Ctss) and protein tyrosine phosphatase non-receptor type 18 (PTPN18)which are either peptidases or proteases were increased at 3 days and peaked at 7 days after stroke onset; a total of 190 genes such as complement component 3 (C3) and C6 were increased 14 days after stroke onset and peaked 14 days later.