C5AR2 and Sepsis: Acteoside was also found to inhibit the high-mobility group box 1 (HMGB1) release in vitro and decrease serum and lung HMGB1 levels in CLP-induced sepsis in vivo (Lee et al., 2006), presumably related to the binding of C5a to the C5L2 protein (Rui et al., 2012), a closest homology with C5aR.