Production of cytokines in hPBMC and mouse splenocytes by CpG-DNA encapsulated in DOPE:CHEMS complex. The levels of IL-6, IL-12, and IFN-γ were measured by ELISA assay (a, b and d) or a Cytokine Bead Array kit (c). hPBMC (a), splenocytes from BALB/c mice (b), and splenocytes from BALB/c TLR9 knockout mice (TLR9-/-, n = 3/group) (d) were stimulated with LPS, free MB-ODN (oligo only) or MB-ODN encapsulated in a DOPE:CHEMS (1:1 ratio) complex for 24 h and the culture supernatants were harvested. The levels of IL-6, IL-12, and IFN-γ were measured with an ELISA assay. (c) BALB/c mice (n = 4/group) were injected i.p with MB-ODN 4531(O) or Lipoplex(O), and sera from the mice were harvested at the indicated times after injection. The concentration of IL-12p70 and IFN-γ in the serum was determined by using a Cytokine Bead Array kit. Each bar and graph represents Mean ± SD values obtained from three or four mice. These experiments were performed 2 times with similar results. *P < 0.05, **P < 0.01 (vs PBS control).