The central nervous system (CNS) was thought to be an immune privileged site due to the ability of blood-brainbarrier (BBB) to shield immune cell entry and protect from the constantly changing circulatory milieu. Nevertheless, activated immune cells readily traverse the BBB, secrete inflammatory cytokines, and mediate many CNS diseases. Neuroinflammatory diseases present major challenges to the health care system and impose substantial economic costs around the world. Current treatments targeting clinical symptoms of CNS diseases have modest therapeutic values in patients. Significant progress has been made in recent years in developing therapeutic strategies for the treatment of neuroinflammatory diseases.