A novel versatile diagnostic method for parrot bornavirus infection
Date:
Authors: Jing-Yuan Chen, Hui-Wen Chen
Parrot bornavirus (PaBV) is the etiological agent of proventricular dilatation disease (PDD), which poses challenges due to its persistent and often asymptomatic nature. In clinical diagnosis, detection of the PaBV antigen is time-consuming and inaccurate, leading to a lack of insight into disease control and prevention. In contrast, virus-induced antibody responses can serve as reliable indicators of viral infection. In the present study, a highly immunogenic PaBV nucleocapsid protein (PaBV4-N) was cloned, fused with a His-tag, and expressed on a virus-free eukaryotic platform using green fluorescent protein as a marker for gene expression. Recombinant PaBV4-N was recognized by an anti-His-tag monoclonal antibody, a PaBV-N-specific polyclonal antibody from immunized mice, and serum from naturally infected parrots. The eukaryotic expression system was applied to chamber slides for immunocytochemical (ICC) staining using the native form of recombinant PaBV4-N as the antigen. A range of parrot serum dilutions (1:50–1:2000) was validated for serological diagnosis, and the developed method, with a process time of 3 hours, demonstrated 100% specificity and 100% sensitivity using 80 parrot serum samples (40 positive and 40 negative). The eukaryotic expression system can be scaled up to meet different demands, and the ICC results can be easily interpreted using regular light microscopy, making it a versatile and portable tool for on-site serological diagnosis for various purposes.