Evaluation Studies of the DEN-2/S-1 Vaccine.
Annual rept. 1 Apr-1 Aug 80,
PUERTO RICO UNIV SAN JUAN
Pagination or Media Count:
Four groups of six nonimmune male rhesus monkeys were inoculated subcutaneously with formulations of dengue type 2 vaccine virus DEN-2S-1. Group A received 1.9 x 104 plague-forming units of vaccine in normal human serum albumin diluent. Group B received the same dose combined with a dengue type 2-immune human serum diluted 11,600, beyound its neutralization endpoint of 1300, but having an immune enhancement titer of 250,000. Groups C and D received 10-fold dilutions of these respective formulations. No migration-inhibitory factor was found when peripheral blood mononuclear leukocytes obtained on day 68 post-immunization from monkeys of all experimental groups were tested. No viremia was detected in any of the monkeys when sera taken on postvaccination days 1 through 12 were inoculated into adult Toxorhynchites amboinensis mosquitoes and LLC-MK2 cells. By day 89, four of the six monkeys had seroconverted by the neutralization test in each of groups, A,B, and C, and three of five monkeys in group D one monkey died from cardiac collapse after anesthesia had seroconverted. Immune enhancement heterologous flavivirus antibodies. In this study, there was no enhancing effect when antibody was mixed with dengue type 2 vaccine virus and injected subcutaneously.
- Medicine and Medical Research