Development Of Immunogolloidal Gold Strip Assay For Detecting The Porcine Reproductive And Respiratory Syndrome Antibody

Porcine reproductive and respiratory syndrome (PRRS) is a porcine reproductive and respiratory syndrome virus (PRRSV) infection in pigs in a reproductive and respiratory system diseases. Pigs are the only natural hosts of this disease. To contact the disease, highly contagious, high incidence of chronic and characterized by high mortality. Pigs grow very slowly, and even growth retardation, serious impact on the economic benefits of pig farming, so the diagnosis of the disease in time help to reduce economic losses. The problem of PRRS is diagnosis for the current time-consuming, to build a method using the colloidal gold immunochromatographic rapid diagnostic technology to detecting PRRS antibodyIn this study, PRRSV POP3 strains as test material, combined with a neutral salt precipitation and gel chromatography to obtain the structure of proteins by SDS-PAGE electrophoresis showed six protein bands with molecular weight were:68.1KD,55.2 KD, 38.9KD,37.6KD,35.1KD,33.9KD, which 55.2KD,38.9KD,37.6KD,35.1KD,33.9KD to PRRSV proteins. Take the purified protein of PRRSV and aluminum gel mixed, vaccine adult rabbits which is 2kg to obtain anti-PRRSV hyperimmune rabbit serum and purified strains of PRRSV proteins by two-way POP3 AGP test, detected the antibody titer is 1:16. By caprylic acid-ammonium sulfate purified serum IgG, showed a molecular weight of 56.5KD and 26.6KD protein band by SDS-PAGE.Using sodium citrate reduction method made 20nm colloidal gold particle size,by UV spectrophotometer (400nm-700nm) scan analysis, the colloidal gold particle size uniformity, about 19.76nm, for immune markers. Let the prepared colloidal gold labeled purified PRRSV proteins,got stable immune colloidal gold. The optimal labeling conditions were:pH 7.8, purified PRRSV protein binding capacity of the tag as 4.8μg/ml. Soaking Nitrocellulose membrane by labeled Immunogold, dried and made the gold standard pad. Also purified PRRSV and rabbit anti-PRRSV IgG protein were used as a diagnostic test strips test line (T line) and control lines (C lines) coated on the nitrocellulose membrane (NC membrane), assembled the test strip. Colloidal gold to determine to the immune dilution 1:1, the concentration of T line package is 1mg/ml, C line coating concentration is 2mg/ml.Compared PRRS antibodies test strip with ELISA in detecting of 36 serum samples. ELISA assay showed that the positive rate was 75%, PRRS antibody diagnostic test strip positive rate was 61.1%. Compared the two methods, the results showed the sensitivity of PRRS antibody test paper was 81.5%, specificity was 100%, the accuracy rate was 86.1%, repeatability is good.PRRS antibody test strip test proved that it's efficient, low cost, high sensitivity and specificity, and easy operation conduvice to grass-roots promotion,has practical value.