The pseudorabies virus R2 non-neuroinvasive vaccine: A proof-of-concept study in pigs

Area of Science:

• Veterinary Virology
• Immunology
• Vaccine Development

Background:

• Neurotropic alpha-herpesviruses establish lifelong latent infections in the peripheral nervous system.
• These viruses can cause severe complications, and effective vaccines are often lacking.
• Pseudorabies virus (PRV) is a significant veterinary alpha-herpesvirus.

Purpose of the Study:

• To evaluate the neuroinvasiveness and protective efficacy of an R2 vaccine derived from PRV in pigs.
• To determine if the PRV R2 vaccine prevents infection of the peripheral nervous system.
• To assess the vaccine's effectiveness against a virulent PRV field strain.

Main Methods:

• Pigs were intranasally vaccinated with the PRV R2 vaccine.
• Vaccine neuroinvasiveness was assessed by detecting the vaccine in the peripheral nervous system.
• Following vaccination, pigs were challenged with a virulent PRV field strain (NIA-3).

Main Results:

• The PRV R2 vaccine did not invade the porcine peripheral nervous system.
• A single intranasal vaccination with R2 conferred significant protection against virulent PRV challenge.
• Pigs vaccinated with R2 showed no signs of neuroinvasion or severe disease.

Conclusions:

• The PRV R2 vaccine is non-neuroinvasive, making it a potentially safer vaccine candidate.
• The R2 vaccine provides effective protection against virulent PRV in its natural host.
• This vaccine design represents a promising advancement for controlling PRV infections in pigs.