3 / 2024-09-22 16:16:42

Identification of ongoing asymptomatic infection with PDCoV via transiently produced IgGs

Abstract: Porcine deltacoronavirus (PDCoV) has the potential to cause zoonotic spillover, especially with the lack of tools that can identify asymptomatically infected pigs. Here, we report a protein-peptide hybrid microarray (PPHM) that is capable of detecting transient produced IgGs (TPIs), which is associated with ongoing infection. Immunoglobin G Sero-dynamics curves aided epitope discovery method was used to identify candidate epitopes of PDCoV. A PPHMPDCoV was obtained after eliminating high antigenic probes through "negative serum identified by viral neutralization assay". Then the PPHMPDCoV was used to identify asymptomatic PDCoV infected pigs aged 28 to 174 days, with or without immunization of PDCoV inactivated vaccine and S protein-based subunit vaccine. We also use the PPHMPDCoV to detect the prevalence of PDCoV in field samples, i.e., 60 pig sera at 28~108 days of age and 70 human sera in China. The results showed that there was asymptomatic infection of PDCoV in pigs, and the infection rate was the highest (15%) at 45 days of age. The serum infection rate of 70 human was 0. This TPI strategy can be used to monitor other pathogens of zoonotic spillover potential due to asymptomatic infection, providing a new means of disease prevention and control surveillance.

Keywords: PDCoV, zoonotic spillover, transient produced IgGs, asymptomatic infection