DPIV elicited broad and long-lasting DENV-nAb responses.

Three groups of rhesus macaques received two intra-muscular administrations, 28 days apart, of the indicated formulations. Sera collected before and after immunization were tested, in duplicate, using a plaque reduction neutralization test (PRNT) for their neutralizing activity against each of the four DENV types. The individual reciprocal serum dilutions associated with 50% reduction in plaque counts (PRNT50 titers) were determined. Shown are the geometric mean titers (GMT) and 95% confidence intervals (CI) (n = 10/group except for Gr.3 at day 254, n = 9). Dotted lines indicate the limit of detection. §Sera were collected in Gr.3 at day 168 instead of 173 in Gr.1-2.