Use of Centrifugal Filter Devices to Concentrate Dengue Virus in Mosquito per os Infection Experiments

Dengue virus (DENV) is an arbovirus transmitted to humans by the bite of infected Aedes mosquitoes. Experimental per os infection of mosquitoes with DENV is usually a preliminary step in virus/vector studies but it requires being able to prepare artificial blood-meals with high virus titers. We report here the convenient use of centrifugal filter devices to quickly concentrate DENV particles in cell-culture supernatants. The median viral titer in concentrated-supernatants was 8.50 log(10) TCID(50)/mL. By using these DENV concentrated-supernatants to prepare infectious blood-meals in Aedes aegypti per os infection experiments, we obtained a mean mosquito-infection rate of 94%. We also evaluated the use of centrifugal filter devices to recover DENV particles from non-infectious blood-meals presented to infected mosquitoes through a feeding membrane to collect their saliva.