Single-dilution indirect solid-phase radioimmunoassay for the detection of anti-pseudorabies immunoglobulin G in swine sera.
A single-dilution indirect solid-phase radioimmunoassay (IRIA) was developed for the detection of low levels of anti-pseudorabies immunoglobulin G in swine sera. The assay derived increased sensitivity from the use of a second amplifying antibody. The IRIA was examined for its stoichiometry, amplification by secondary antibody, advantage of a single-dilution assay vs an end-point titration, sensitivity, and specificity. The assay had a near linear dose-response relationship with positive sera (serum-neutralization titer less than or equal to 1:16) and lacked a dose response with negative sera. With addition of the secondary antibody, the IRIA was enhanced 8.5-fold in net specific binding, and the end-point titer was amplified 32-fold. The single-dilution assay was proved to be a feasible test, compared with end-point titration. Anti-pseudorabies virus titers were at least 128-fold higher by IRIA than those by serum-neutralization test. Evidence indicated that there may be minimal or no cross-reactivity of IRIA antigen with anti-infectious bovine rhinotracheitis sera. The single-dilution IRIA was a rapid and sensitive test for anti-pseudorabies virus immunoglobulin G in swine sera.
D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis*; D007074:Immunoglobulin G / Q000032:analysis*; D009500:Neutralization Tests; D011557:Pseudorabies / Q000276:immunology / Q000662:veterinary*; D011863:Radioimmunoassay / Q000379:methods; D013552:Swine; D013553:Swine Diseases / Q000276:immunology*
D000914:Antibodies, Viral; D007074:Immunoglobulin G