The expressions of p-PI3K, p-AKT, exosome markers (CD9, CD63, and TSG101), p-ERK1/2, TNF-α, IFN-γ, IL-1β, and cleaved-caspase-3/-9 were significantly increased in septic mice vs. control mice, and these proteins were declined dramatically in TLR9−/− BMT mice vs. WT BMT mice in sepsis mice models. Here, CD9 is linked to Sepsis.