Evaluation of a monoclonal antibody blocking ELISA for the detection of group-specific antibodies to bluetongue virus in experimental and field sera.
In order to overcome serological cross-reactions among orbivirus serogroups, which can hinder the accurate diagnosis of bluetongue virus (BTV) infection of livestock, a blocking ELISA (B-ELISA) incorporating a monoclonal antibody (20E9B7G2) with specificity for the BTV serogroup was developed. Experimental antisera raised to South African BTV serotypes 1 to 19 were tested in the B-ELISA and all blocked the binding of 20E9B7G2 to BTV antigen. The sensitivity and specificity of the assay was evaluated with a range of experimental and field sera and compared to a sensitive indirect ELISA (I-ELISA) for the detection of BTV-specific antibodies. The specificity of the B-ELISA was absolute for antibodies to BTV, showing no cross-reaction with experimental antisera to serotypes of the closely related orbivirus causing epizootic haemorrhagic disease of deer. The sensitivity of the B-ELISA exceeded that of the I-ELISA. In particular, the B-ELISA detected a BTV-specific antibody response much earlier after infection that the I-ELISA, while still exhibiting full sensitivity to BTV antibody titres several months after infection.
Lunt
R A
RA
CSIRO, Australian Animal Health Laboratory, Geelong, Victoria.
White
J R
JR
Blacksell
S D
SD
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000914:Antibodies, Viral / Q000032:analysis*; D001819:Bluetongue / Q000276:immunology*; D001820:Bluetongue virus / Q000276:immunology*; D002417:Cattle; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D012087:Reoviridae / Q000276:immunology*; D012756:Sheep; D013997:Time Factors
D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral