Modelling Microglial Innate Immune Memory In Vitro: Understanding the Role of Aerobic Glycolysis in Innate Immune...

Area of Science:

• Neuroimmunology
• Cellular immunology
• Metabolic immunology

Background:

• Microglia, the brain's immune cells, exhibit memory states like training and tolerance.
• These memory states influence responses to subsequent inflammatory stimuli.
• Mechanisms distinguishing training from tolerance remain unclear.

Purpose of the Study:

• To investigate the mechanisms differentiating microglial training and tolerance memory states.
• To explore the role of aerobic glycolysis in establishing immune tolerance.
• To understand how B-cell-activating factor (BAFF) and lipopolysaccharide (LPS) priming affect microglial responses.

Main Methods:

• In vitro study using BV2 microglial cells.
• Priming with BAFF or LPS, followed by a second LPS stimulus.
• Assessment of inflammatory cytokine expression.
• Investigation of aerobic glycolysis using sodium oxamate to inhibit it.

Main Results:

• BAFF priming followed by LPS induced enhanced responses (training).
• LPS priming followed by LPS induced attenuated responses (tolerance).
• LPS, unlike BAFF, induced aerobic glycolysis, which was essential for tolerance induction and blocked by sodium oxamate.

Conclusions:

• Aerobic glycolysis is a critical mechanism for inducing innate immune tolerance in microglia.
• Inhibition of aerobic glycolysis prevents the establishment of the tolerized memory state.
• Microglia in a tolerized state are unable to induce aerobic glycolysis upon restimulation.