Failure of dengue-2 virus antibody to interfere with the isolation of dengue-2 virus from Aedes aegypti (Diptera : Culicidae)

When isolating dengue virus (DEN) from mosquitoes collected in endemic area s, pools may contain both anti-dengue antibodies from freshly engorged fema les and virus from DEN infected females. To determine if these antibodies m a) interfere with virus isolation, we simulated the isolation procedure usi ng Aedes aegypti (L.) that we infected with the 16681 strain of dengue type 2 virus by intrathoracic inoculation. At 7 d postinfection, we allowed fem ales to engorge on immunized or normal mouse blood. Virus in a mixture of a nti-dengue-e antibodies and dengue-2 virus became inactive after incubation at 37 degrees C for 1 h, but remained infective without incubation. Theref ore, at ambient conditions antibodies would not interfere with virus isolat ion from field-collected Ac, aegypti from endemic areas. In addition, DEN a ntibodies enhanced virus replication when inoculated into Ae. aegypti, but not C6/36 cells. The mechanism for this in vitro antibody enhancement of in fection remains unclear.