EVALUATION OF A KINETIC ENZYME-LINKED-IMMUNOSORBENT-ASSAY FOR DETECTION OF CAPRINE ARTHRITIS-ENCEPHALITIS VIRUS-SPECIFIC ANTIBODIES

A kinetic indirect enzyme-linked immunosorbent assay (k-ELISA) was eva luated for detection of antibody to caprine arthritis-encephalitis vir us (CAEV), using sodium dodecyl sulfate-treated CAEV-63 as antigen. Tw o hundred fifteen caprine sera submitted to the diagnostic laboratory were tested for CAEV antibody by the k-ELISA and by immunoprecipitatio n of [S-35]-Methionine-labeled CAEV. A k-ELISA positive cutoff point o f 80 yielded a sensitivity of 94.4% and a specificity of 100%, as comp ared with immunoprecipitation. A k-ELISA cutoff point of 50 resulted i n a sensitivity of 100%, with 95.6% specificity. When sera with k-ELIS A scores between 50 and 80 were considered suspect, testing of 1,001 d iagnostic sera resulted in < 1.5% suspect reactions. Using the 80 cuto ff point, the CAEV k-ELISA had good sensitivity and specificity, with the added advantages of quick turn-around time, few suspect reactions, and adaptability to large numbers of samples.