Immune responses induced by DNA vaccines bearing Spike gene of PEDV combined with porcine IL-18

► Generation of three distinct DNA constructs encoding S protein of PEDV, the N-terminal fragment (S1) of PEDV and porcine interleukin-18 (pIL-18). ► Immune responses of above-mentioned DNA constructs were evaluated systematically using mouse model. ► PEDV-S and the combination of PEDV-S1 with pIL-18 induced the strongest responses but that pIL-18 had no adjuvant effects when given in combination with PEDV-S1.