IFNG and dengue disease: Only 41% of volunteers seroconverted with NAb after immunization with the highest DNA dose (three i.m. injections of 5 mg in 0-,1-, and 5-months), using a needle-free Biojector 2000, while a tetravalent T-cell response with IFN-γ production upon stimulation with E proteins from all dengue serotypes was noted after both low and high DNA doses.