Development of Nonaggregating Poly-A Tailed Immunostimulatory A/D Type CpG Oligodeoxynucleotides Applicable for Clinical Use

Figure 2

G-hexamer-less D35 ODNs required DOTAP for their immunostimulatory activities. Human PBMCs were stimulated with the indicated synthetic ODNs (1 μM) with or without DOTPA for 24 hours. IFN-α and IL-6 productions in the supernatants were examined by ELISA. DOTAP revived the immunostimulatory activities of D35A, D35T, and D35C; those are A/D type ODNs which do not contain G-hexamer. These ODNs did not show any immunostimulatory activities without DOTAP. The bar graphs indicate the concentrations from a single well of each stimulation. IFN-α production overed the ELISA measurement maximum (ca. 5000 pg/mL) with DOTAP in Exp5 and Exp6.