Assay to Determine the Virus Infectious Dose of Drosophila C Virus in Cultured Insect Cells

Drosophila C virus, or DCV, a positive single-stranded RNA virus, commonly infects Drosophila melanogaster.

During infection, DCV uses host cell machinery to replicate the viral genome, eventually producing virus particles. Infected cells exhibit cytopathic effects, CPE, and undergo lysis or die without lysis due to their inability to divide.

To determine the average virus tissue culture infective dose, the DCV concentration at which half the infected cells display CPE, begin with serially diluted DCV suspensions.

Transfer to a multi-well plate containing semi-adherent Drosophila S2* cells derived from late-stage embryos of Drosophila melanogaster, a natural DCV host. Wells containing medium and cells serve as negative controls.

Incubate for the virus to infect the cells. Virus-infected cells display CPE via cell damage and death. Post-incubation, observe the wells under the microscope.

Identify CPE-positive and negative wells across dilutions. Use a suitable method to determine the average virus tissue culture infective dose of DCV.