Early pathogenesis in rabbit hemorrhagic disease virus 2
Alicia D O'Toole1, Fawzi M Mohamed2, Jian Zhang1
1Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA.
Microbial Pathogenesis
|October 11, 2022
Summary
Rabbit hemorrhagic disease virus 2 (RHDV2) initially targets the gastrointestinal tract before spreading to the liver. This study details RHDV2 tissue distribution and the early innate immune response in rabbits.
Area of Science:
- Veterinary Virology
- Immunology
- Pathogenesis Research
Background:
- Rabbit hemorrhagic disease virus 2 (RHDV2) is a significant threat to rabbit populations.
- Understanding RHDV2 pathogenesis and host immune response is crucial for disease management.
Purpose of the Study:
- To investigate the early tissue distribution of RHDV2 in orally inoculated rabbits.
- To characterize the innate immune response, including cytokine expression, following RHDV2 infection.
Main Methods:
- Oral inoculation of rabbits (Oryctolagus cuniculus) with RHDV2 liver homogenate.
- Monitoring of rabbits and tissue/swab collection at multiple time points post-inoculation (12-144 h).
- RT-rtPCR and RNAscope techniques used for viral detection and gene expression analysis (TNF-α, IL-6, IL-1β).
Main Results:
- RHDV2 was detected in the liver by RT-rtPCR in inoculated rabbits.
- Viral genomic RNA was found in the gastrointestinal tract and liver (by 36 h post-inoculation) using RNAscope.
- Increased mRNA expression of TNF-α, IL-6, and IL-1β was observed in the liver and spleen by 48 h post-inoculation.
Conclusions:
- This study elucidates the early dissemination of RHDV2 from the GI tract to the liver.
- The findings highlight the local innate immune response, indicated by cytokine upregulation, during early RHDV2 infection.
- This research contributes to a better understanding of RHDV2 pathogenesis in rabbits.
