Establishment and application of PDCoV antigen-specific DAS-ELISA detection method

Area of Science:

• Veterinary Virology
• Immunodiagnostics
• Swine Infectious Diseases

Background:

• Porcine deltacoronavirus (PDCoV) causes severe enteritis in young pigs, leading to significant economic losses.
• Cross-species and zoonotic transmission potential of PDCoV necessitates rapid diagnostic methods.
• Early detection is crucial for managing PDCoV outbreaks and preventing widespread infection.

Purpose of the Study:

• To develop and validate a convenient and reliable diagnostic assay for Porcine deltacoronavirus (PDCoV).
• To establish an enzyme-linked immunosorbent assay (DAS-ELISA) for detecting PDCoV in swine populations.

Main Methods:

• Development of a DAS-ELISA using a monoclonal capture antibody and a polyclonal HRP-labeled detection antibody, both targeting the PDCoV nucleocapsid (N) protein.
• Validation of the DAS-ELISA against established methods like RT-PCR and TCID50.
• Assessment of specificity, limit of detection, and diagnostic accuracy using clinical samples.

Main Results:

• The developed DAS-ELISA demonstrated high specificity for PDCoV, with no cross-reactivity observed with other swine diarrhea viruses.
• The limit of detection was determined to be 10^3 TCID50/mL for PDCoV.
• Analysis of 239 pig samples showed a high coincidence rate of 97.07% (κ=0.922) compared to RT-PCR.
• The assay accurately measured PDCoV growth curves and tissue distribution, consistent with other quantitative methods.

Conclusions:

• The developed DAS-ELISA is a convenient and accurate method for early clinical detection of PDCoV in pigs.
• This assay can serve as a valuable alternative for routine laboratory diagnosis of PDCoV infections.
• The findings support the use of DAS-ELISA for effective disease surveillance and control programs in swine herds.