Development and application of an immuoperoxidase monolayer assay for the detection of PRRSV

Abstract Background Porcine reproductive and respiratory syndrome (PRRS), caused by porcine reproductive and respiratory syndrome virus (PRRSV), is a highly contagious disease with high morbidity and mortality that affects the global swine industry. So far, there is still a widespread dissemination of PRRSV with obvious genetic variations in swine population, resulting in huge economic losses annually. Therefore, accurate laboratory diagnosis is needed to quickly confirm PRRSV infection. Results An immunoperoxidase monolayer assay (IPMA) was developed for the specific and sensitive detection of PRRSV based on a broad-spectrum anti-PRRSV monoclonal antibody (mAb) 28F6. The mAb 28F6-based IPMA could specifically detect PRRSV and possessed no cross-reactions with CSFV, PCV2, and PEDV. Sensitivity analysis showed that the limit of detection of the IPMA reached 10− 2.25 TCID50/100 µL. There was no significant difference in the detection of PRRSV of different passages with different batches of mAb 28F6, indicating that the IPMA had good repeatability. In addition, the IPMA could recognize a number of PRRSV variants including field strains such as BJ-4, HN07-1, and NADC30-like strain, as well as vaccine strains like HuN4-F112, JXA1-R, TJM-F92, GDr180, VR2332, CH-1R, and R98. Validation of the IPMA showed that it was in 100% consistency with qRT-PCR on the detection of 108 clinical samples. Conclusions The IPMA could meet the demand for the specific and sensitive detection of PRRSV, which is helpful for accurate monitoring and early warning of PRRSV infections.