Stroke is the 4th leading cause of death in United States with an estimated 1 death every 4 minutes. On average, someone suffers from stroke in United States every 40th second. Stroke recurs in 1 out of 4 stroke patients. About 87% of the strokes are as a result of ischemic insult. The total economic burden from stroke accounts to 38.6 billion dollars per year. Stroke is also one of the leading causes of long term disability. Current stroke therapies concentrate mainly on acute revascularization, sub-acute rehabilitation and secondary prevention.