Figure 3From: Generation of an infectious clone of HuN4-F112, an attenuated live vaccine strain of porcine reproductive and respiratory syndrome virusImmunofluorescence assay. MARC-145 cells infected with the 3rd passage culture of the viruses were fixed 48 h post-inoculation and examined by immunofluoresence assay with the anti-N monoclonal antibody (N3H2) of PRRSV.Back to article page