β-Glucan-Induced Trained Immunity in Dogs.

Area of Science:

• Comparative immunology
• Innate immune memory
• Veterinary immunology

Background:

• Trained immunity, the innate immune system's ability to 'remember' pathogens, was discovered in the early 2010s.
• This phenomenon involves epigenetic and metabolic reprogramming of immune cells, leading to enhanced responses.
• Previous research focused on humans and mice, but its presence in other veterinary species remained unexplored.

Purpose of the Study:

• To investigate the existence and characteristics of trained immunity in dogs, a species of veterinary importance.
• To adapt and validate an in vitro model for studying trained innate immunity in canine monocytes.

Main Methods:

• An in vitro model using canine blood-enriched monocytes was established.
• Monocytes were stimulated with β-glucans, a known inducer of trained immunity.
• The production of pro-inflammatory and anti-microbial compounds was measured following subsequent bacterial challenge.

Main Results:

• Canine monocytes stimulated with β-glucans exhibited enhanced production of inflammatory and anti-microbial factors.
• This enhanced response occurred upon subsequent exposure to bacterial stimuli, confirming trained immunity.
• The study identified conserved cellular mechanisms, including epigenetic and metabolic regulations, similar to those in mice and humans.

Conclusions:

• This research provides the first evidence of trained immunity in dogs.
• The findings confirm the presence of trained immunity signatures in another mammalian species.
• The study highlights conserved underlying cellular mechanisms across different mammalian species, with implications for veterinary medicine.