Flaviviruses are important human pathogens worldwide. Diagnostic testing for these viruses is difficult because many of the pathogens require specialized biocontainment. To address this issue, we generated 39 virus-like particle (VLP)- and nonstructural
protein 1 (NS1)-secreting stable cell lines in HEK-293 cells of 13 different flaviviruses, including
dengue,
yellow fever,
Japanese encephalitis, West Nile,
St. Louis encephalitis, Zika, Rocio, Ilheus, Usutu, and Powassan viruses.
Antigen secretion was stable for at least 10 cell passages, as measured by
enzyme-linked
immunosorbent assays and immunofluorescence assays. Thirty-five cell lines (90%) had stable
antigen expression over 10 passages, with three of these cell lines (7%) increasing in
antigen expression and one cell line (3%) decreasing in
antigen expression.
Antigen secretion in the HEK-293 cell lines was higher than in previously developed COS-1 cell line counterparts. These
antigens can replace current
antigens derived from live or inactivated virus for safer use in diagnostic testing. IMPORTANCE Serological diagnostic testing for flaviviral
infections is hindered by the need for specialized biocontainment for preparation of
reagents and assay implementation. The use of previously developed COS-1 cell lines secreting noninfectious recombinant
viral antigen is limited due to diminished
antigen secretion over time. Here, we describe the generation of 39 flaviviral virus-like particle (VLP)- and nonstructural
protein 1 (NS1)-secreting stable cell lines in HEK-293 cells representing 13 medically important flaviviruses.
Antigen production was more stable and statistically higher in these newly developed cell lines than in their COS-1 cell line counterparts. The use of these cell lines for production of flaviviral
antigens will expand serological diagnostic testing of flaviviruses worldwide.