Protocol for simultaneous detection of PRRS virus infection and dying cell populations by a flow cytometry double-staining approach

When investigating cellular responses to viral infections, there is a need to quantitatively distinguish between dying cells, infected cells, and cells that are both infected and dying. Here, we present a protocol to simultaneously detect porcine reproductive and respiratory syndrome virus (PRRSV) infection and cell death using a flow cytometry double-staining approach. We describe steps for cell seeding, infection, and collection; staining dead cells; sample fixation; and cell permeabilization. We then detail procedures for immunostaining and flow cytometry analysis.