FOSB and Sepsis: Our study extends these in vitro findings by demonstrating that (a) the ACTH test induces multiple cytokines, including IL-6, through activation of the AP-1 and MAPK pathways in vivo; (b) the ACTH test induces lethal levels of IL-6 in the context of sepsis; and (c) the ACTH test moderately decreases the survival rate in septic mice.