Antigenic analysis of West Nile virus strains using monoclonal antibodies

Abstract

Seventeen monoclonal antibodies (MAbs) were prepared against the flavivirus West Nile strain H442. While the majority of these were specific for the major envelope protein, MAbs directed against the NS1 and ns4a nonstructural proteins were also identified. The MAbs were tested by indirect immunofluorescence against 16 southern African West Nile (WN) isolates, representative strains from the two main WN antigenic groups and several viruses from other flavivirus complexes. The MAb reactivities ranged from WN strain-specific to broadly flavivirus-group reactive. Comparison of the local isolates revealed the presence of several different strains, all of which were antigenically distinct from the representative strains of the two WN antigenic groups.

Topological mapping of antigenic sites on the Rift Valley fever virus envelope glycoproteins using monoclonal antibodies

“…The method for production and maintenance of monoclonal antibodies was based on that as described by Besselaar and Blackburn [3]. Positive clones were selected by testing the supernatants of the hybridoma cultures for antibody excretion using an ELISA with purified glycoprotein as the capture antigen.…”

“…1000 Ci.mmol; Amersham Int., U.K.) for 4-20 h post-infection at 37 °C. The cells were washed with cold PBS, lysed with NP-40 buffer [3] and made 0.1% (w/v) with respect to SDS. The lysates were disrupted with a probe sonicator, clarified by centrifugation at 18000 g for 30 min and the supernatants used for MAb immunoprecipitation.…”

“…Immunoprecipitation was carried out as described by Bessetaar and Blackburn [3] with the exception that diallyltartardiamide (DATD, Sigma, St Louis, U.S.A.) was substituted for bis acrylamide in the 12% gels to achieve better resolution of the GI and G2 proteins as reported by Smith and Brown [31]. The gels were treated with Amplify (Amersham) for V2 h, dried and exposed at -70 °C.…”

The Relationships between West Nile and Kunjin Viruses

“…Antigenic profiles of each isolate were compared by using a panel of anti-KUN monoclonal antibodies (MAbs) (26,27) and anti-WN MAbs (28,29) in ELISA as described (26). All MAbs were produced to the E protein except for 3.1112G, which was specific for the NS1 protein.…”

Extensive nucleotide changes and deletions within the envelope glycoprotein gene of Euro-African West Nile viruses.

“…Thus, Hammam et al (1965) found that Indian and African WN virus isolates have different haemagglutination inhibition kinetics. Studies of cDNA\RNA heteroduplex restriction profiles and\or reactivity toward monoclonal antibodies (Besselaar & Blackburn, 1988 ;Mathiot et al, 1990) have identified several WN virus variants. More recently, Porter et al (1993) sequenced NS3 protein gene fragments of seven African and one Indian strains and defined three categories on the basis of nucleotide sequence similarity.…”