Long-term stability of antibody responses elicited by Dengue virus envelope DIII-based DNA vaccines

Dengue virus (DENV) is one the most important viral pathogens worldwide. Currently there is an imperative need for a reliable vaccine capable of inducing durable protection against all four serotypes. We have previously reported strongly neutralizing and highly specific antibody responses from all four serotypes to a DNA vaccine based on an engineered version of DENV E protein's domain III (DIII). Here, we show that monovalent and tetravalent immunizations with the DIII-based DNA vaccines are also capable of inducing highly stable antibody responses that remain strongly neutralizing over long periods of time. Our results demonstrate that DNA-vaccinated mice maintain a strong antibody response in terms of titre, avidity and virus-neutralizing capability 1 year after immunization.