Animals models for dengue virus infection have not been established so far. Non-human primates provide the closest model because they develop viremia with a time course that resembles human dengue virus infection. Such a response may be useful in testing candidate dengue vaccines which have so far not been successfully generated. the study aims to determine the antibody response in Macaca fascicularis immunized with short peptides derived from the envelope of the dengue virus .
Briefly, foru peptides that were bound by the monoclonal antibodies generated against the dengue 2 virus were selected from a phage display library. These peptides were synthesized and subcutaneously injected, individually and as a cocktail, in 1-year old monkeys, 5 times at 3-week intervals. Blood extraction (5mL) was performed prior to each injection. For controls, moneys were injected with the whole dengue virus and sterile distilled water, separately. Specific antibody response to the antigens was determined using ELISa. Microtiter plates were coated with the peptide cocktail to capture antibodies generated against the peptides. Peroxidase-antibody conjugates were used to visualized the captured anti-peptide antibodies via a color reaction which is measured using an ELISA-plate reader. Preliminary results showed that the monkeys injected with the peptide cocktail elicited antibodies to the peptides 3 weeks after the first injection, which doubled after the 2nd injection and was sustained throughout the rest of the duration. Monkeys injected with individual peptides developed antibodies after the second injection, but a lower level in contrast with the peptide cocktail. Further studies are needed to determine of the monkey antibody response will be capable of neutralizing the dengue virus.