Development of a blocking ELISA for Caprine parainfluenza virus type 3
Li Mao1, Wenliang Li2, Tianci Zhou2
1Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, National Center for Engineering Research of Veterinary Bio-products, Nanjing 210014, China; State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, CAAS, Lanzhou 730046, China.
Abstract:
Caprine parainfluenza virus type 3 (CPIV3) is a novel pathogen mainly causing respiratory diseases in goats. At present, there are no high throughput and rapid testing methods available for epidemiological investigation. In this study, we designed a modified method for selection of hybridomas that secrete monoclonal antibodies (mAb) specific for CPIV3. The monoclonal antibodies were obtained by combination of indirect enzyme-linked immunosorbent assay (iELISA) and blocking ELISA (bELISA). The technique was efficient to determine each mAb with specificity and sensitivity. One bELISA was validated for the serological diagnosis of CPIV3. After optimization conditions were established, a total of 205 reference goat sera were tested in parallel by bELISA and by virus neutralization (VN) for their relative performances. The cut-off point was ultimately defined as 33.6% by ROC curve analysis. The bELISA specificity and sensitivity were 99.2% and 98.7%, respectively, and agreement with the VN test was >99.0%. Furthermore, testing another 2919 goat sera by bELISA demonstrated 39.3% prevalence in the goat population, more sensitive than HI detection. This new bELISA would offer higher throughput, sensitivity, and specific detection for CPIV3, and will be of great value not only for surveillance, but also for monitoring the efficiency of vaccination programs in the future.
