In accordance, some protection of septic mice has been shown by the application of a C5a receptor antagonist (60) . Furthermore, C5aR antagonism during sepsis led to a changed cytokine profile, such as decreased levels of tumor necrosis factor-α and IL-6, suggesting a direct or indirect role in the synthesis of these factors (40) . Czermak et al. (61) showed an enhanced survival rate of septic rats treated with a C5a antibody. Additionally, these authors found that C5a binds to neutrophils, which led to inactivation of their functions.