Construction of Reverse Genetics System for Feline Calicivirus FCV-BJ616 and Proteomic Analysis.

Area of Science:

• Veterinary Virology
• Molecular Pathogenesis
• Immunology

Background:

• Feline calicivirus (FCV) is a major cause of feline upper respiratory tract infections and oral disease.
• FCV's genetic diversity hinders effective prevention and control strategies.
• Understanding FCV pathogenesis is crucial for developing targeted therapies and vaccines.

Purpose of the Study:

• To isolate and characterize the FCV-BJ616 strain.
• To establish a functional reverse-genetics system for FCV.
• To investigate the molecular mechanisms underlying FCV-BJ616 pathogenesis and host immune response.

Main Methods:

• Plaque cloning, electron microscopy, immunofluorescence, and Western blotting for virus characterization.
• Reverse genetics to create a rescued infectious clone (rFCV-BJ616).
• In vivo infection studies in cats, proteomic analysis, and ELISA for cytokine profiling.

Main Results:

• A stable, infectious clone of FCV-BJ616 (rFCV-BJ616) was successfully rescued.
• rFCV-BJ616 demonstrated wild-type virulence, causing fever, weight loss, and multiorgan pathology.
• FCV infection upregulated inflammatory mediators (IL-8, S100A8/A9, TLR3) and transiently modulated antiviral signaling (IFN-β, STAT1).

Conclusions:

• The study provides a valuable reverse-genetics platform for FCV genome manipulation.
• Insights into FCV-BJ616 pathogenesis and immune response pave the way for antibody-based therapies.
• This work supports the development of broad-spectrum FCV vaccines.