High Mobility Group protein B1 protein （HMGB1） is the high mobility group box family of non-histone chromosomal proteins. Human HMGB1 is expressed as a 25 kDa single chain polypeptide containing three domains: two N-terminal HMG boxes A and B, and a negatively charged 30 a.a. C-terminal region that contains only Asp and Glu. Post-translational modification on HMGB1 have been reported, affects its localization, receptor interactions, and function. HMGB1, with a disulfide bond between C23 and C45 , have been reported that cause cytokine production and the activation of NF-κB. Otherwise, the fully oxidized form has no immune function, losing its proinflammatory effect and the apoptotic cell death activation function.