Immune Cell Signaling in Feline Infectious Peritonitis Virus Infection and Implications for Vaccine Design

Area of Science:

• Veterinary Virology
• Immunology
• Vaccine Development

Background:

• Feline infectious peritonitis virus (FIPV) causes a challenging disease with no consistently effective vaccine.
• Disease severity depends on host immune responses, particularly macrophage and monocyte signaling, leading to immunopathology.
• Previous FIPV vaccines have shown inconsistent protection and sometimes enhanced disease.

Purpose of the Study:

• To review current knowledge of immune cell signaling pathways in FIPV infection.
• To explore how these pathways influence vaccine-induced immunity.
• To propose reframed vaccine development strategies for FIPV.

Main Methods:

• Review of literature on immune signaling pathways (Toll-like receptors, MAPKs, NF-κB, cytokines, Fc receptors, autophagy) in FIPV.
• Integration of data on immune signaling kinetics, antibody functionality, adjuvant effects, and platform-specific immune signatures.
• Analysis of how these mechanisms shape vaccine-induced immunity.

Main Results:

• FIPV disease severity is linked to excessive inflammation driven by macrophage and monocyte signaling.
• Vaccine-induced immune responses mimicking pathogenic pathways can exacerbate disease.
• Understanding specific immune signaling pathways is crucial for effective FIPV vaccine design.

Conclusions:

• Future FIPV vaccine development should focus on modulating host immune responses rather than solely maximizing immunogenicity.
• Strategies should aim to limit sustained macrophage activation and pro-inflammatory cytokine amplification.
• This approach may reduce antibody-dependent enhancement and immunopathology, offering broader lessons for vaccine design.