In a CLP model of sepsis, Gao et al. demonstrated that serum exosomes from septic mice obtained 2 h post injury contain significantly elevated levels of pro-inflammatory cytokines IL-1β, IL-2, IL-6, and TNF-α whereas the lymphocyte chemoattractants CCL2 (MCP-1) and CCL3 (MIP-1α) and anti-inflammatory cytokines IL-4 and IL-10 were not increased until 12 h and 24–48 h, respectively. Here, CCL3 is linked to Sepsis.