ZIKV reporter virus particle (Z-RVP) reagent

Reporter virus particles (RVP) were purchased from Integral Molecular (Philadelphia, PA) ZIKV reporter virus particles (Z-RVPs) contain CprM/E from ZIKV strain SPH2015 packaged within the particle a DENV-based replicon with the Renilla luciferase gene [32]. The Z-RVP reagent is replication deficient but is capable of infecting permissive cells to deliver the replicon which drives the expression of Renilla luciferase. Addition of an appropriate substrate results in the generation of a chemiluminescent signal, which is measured to determine sample neutralization activity. The SPH2015 strain of ZIKV was the first strain isolated from the outbreak in Brazil in 2015 and has a high degree of genetic similarity to other ZIKV strains from the same outbreak in South and Central America during 2015–16 and other recent Asian-lineage ZIKV strains [53].

Eight RVP lots were used during the development of the assay (lot 135 A-D, 164 A-D). Each lot number represents a different production run, each letter of the lot represents a different harvest date.