A fast way to lose antibodies

Area of Science:

• Immunology
• Metabolism
• Cell Biology

Background:

• Long-lived plasma cells are crucial for sustained antibody titers and humoral immunity.
• The physiological regulators of long-lived plasma cell persistence are not fully understood.

Purpose of the Study:

• To investigate the impact of fasting-induced metabolites on long-lived plasma cell stability.
• To elucidate the molecular mechanisms by which these metabolites affect plasma cell niches.

Main Methods:

• Investigated the role of beta-hydroxybutyrate (BHB) in regulating plasma cell survival.
• Examined the signaling pathway involving Hydroxycarboxylic acid receptor 2 (HCAR2).
• Assessed the effects on bone marrow plasma cell niches and humoral immunity.

Main Results:

• Fasting-induced beta-hydroxybutyrate destabilizes bone marrow plasma cell niches.
• This destabilization occurs through signaling mediated by HCAR2.
• The process accelerates the decline of long-lived plasma cells and reduces humoral immunity.

Conclusions:

• Beta-hydroxybutyrate, a fasting metabolite, negatively regulates long-lived plasma cell persistence.
• HCAR2 signaling is a key mediator in the loss of plasma cells during fasting.
• These findings reveal a novel mechanism impacting humoral immunity duration.