HMGB1 and Stroke: Cerebral tissue necrosis leads to spill over of otherwise intracellular proteins such as heat shock proteins, hyaluronic acid, fibronectin and high mobility group box 1 (HMGB1) into the extracellular compartment that can become detectable in the plasma of patients after cerebral ischemia in the context of stroke or CA/CPR [10–12].