Development of a novel assay to assess the avidity of dengue virus-specific antibodies elicited in response to a tetravalent dengue vaccine
Abstract Antibody affinity maturation is a critical step in development of functional antiviral immunity, however, accurate measurement of affinity maturation of polyclonal serum antibody responses to particulate antigens such as virions is challenging. We describe a novel avidity assay employing bio-layer interferometry and dengue virus-like particles. After validation using anti-dengue monoclonal antibodies, the assay was used to assess avidity of antibody responses to a tetravalent dengue vaccine candidate (TAK-003) in children, adolescents and adults during two Phase 2 clinical trials conducted in dengue endemic regions. Vaccination increased avidity index and avidity remained high through one-year post vaccination. Neutralizing antibody titers and avidity index did not correlate overall, however, a correlation was observed between neutralizing antibody titer and avidity index in those subjects with the highest degree of antibody affinity maturation. Therefore, vaccination with TAK-003 stimulates polyclonal affinity maturation and functional antibody responses including neutralizing antibodies.