Validation of Pseudo Virus Neutralization Assay (PVNT) for Domestic Cattle SARS-COV-2 Natural Infection
Open Access
- Author:
- Quraishi, Meysoon
- Area of Honors:
- Veterinary and Biomedical Sciences
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Ruth H Nissly, Thesis Supervisor
Robert John Vansaun, Thesis Honors Advisor - Keywords:
- SARS-CoV-2
pseudo virus neutralization assay
Domestic Cattle
indirect ELISA
PVNT
COVID-19 - Abstract:
- The emergence of the novel coronavirus, SARS-CoV-2, and the subsequent COVID-19 pandemic have posed unprecedented challenges for both global public health for humans and animals alike. With the sudden onset of the pandemic, the need for accurate and accessible diagnostic assays for humans and animals are necessary to track and reduce the spread of the virus. Domestic cattle serve as a potential threatening reservoir due to their ability to contract the virus, proximity to humans, and potential exposure to the virus via white-tailed deer populations. This study focuses on assessing the accuracy of the pseudo virus neutralizing (PVNT) assay in detecting SARS-CoV-2 antibodies in naturally infected cattle populations. Following the collection of both pandemic and pre-pandemic samples, the study evaluated the performance of PVNT assays, with a specific emphasis on the Delta and Omicron variants. The results revealed a complete lack of sensitivity, specificity, with low to 0% positive predictive values, and negative predictive values for both Delta and Omicron PVNT assays. Further investigation into the underlying causes of these inaccuracies was conducted, including exploring potential cross-reactivity with bovine coronavirus (BCoV). However, experiments did not find evidence to support BCoV antibodies as contributors to the observed inaccuracies. Additionally, metadata suggests that maternal antibodies and geographical location did not significantly impact PVNT results. These findings led to proposals of possible strategies to optimize serum dilutions as well as investigate lentiviral vector scaffolding as a means on non-specific binding. In conclusion, this study highlights challenges in PVNT testing for SARS-CoV-2 antibodies in cattle, emphasizing the need to address sample composition and assay methodology for improved diagnostics, crucial for controlling viral spread and minimizing zoonotic transmission risks.