FAS and Sepsis: The innate immune response is immediately alerted leading to the convergent and rapid release of chemokines and cytokines that includes TNF-α, leukotrienes, interleukin 1 (IL1), IL6, IL8 and Fas which in turn have a profound impact on neutrophil migration and activation and will also prepare the bone marrow for recruitment of cells to the periphery [23, 24].Since the response of the bone marrow to sepsis is release of an abundance of neutrophils, even immature, the pronounced increase of [11C]NES in bone marrow one hour after induction of sepsis is counterintuitive.