Stable expression and potential use of west nile virus envelope glycoproteins preM/E as antigen in diagnostic tests

Abstract

West Nile virus (WNV) envelope glycoproteins preM/E were stably expressed in baby hamster kidney cells and tested as antigen in a fluorescent antibody assay for WNV antibodies. Sera from horses, mice and chicken immunized with an inactivated WNV vaccine and, less consistently, sera from horses acutely infected with WNV, reacted specifically with viral antigens present in preM/E-expressing cells.

Keywords: M/E glycoproteins; WNV; West Nile virus; diagnostic; stable expression.

Figure 1

Reactivity of antibodies from different sources with WNV proteins preM and E expressed in BHK-21 cells, by immunofluorescence. Left column: BHK-M/E cells; right column: control BHK-21 cells. These cells were incubated with mouse ascitis fluid (MIAF) (A and B); flavivirus-specific monoclonal antibody HB-112 (C and D); serum from a horse immunized with a WNV inactivated vaccine (E and F) and serum from a mouse immunized with the WNV vaccine (G and H). Positive reaction was observed only in sera incubated with BHK-M/E cells. Photographs correspond to IFA performed on BHK-M/E cells at passages #3 (A); # 22 (C) and # 8 (E-G), and BHK-21 at passage #35.