Short-Chain Fatty Acids Regulate Cytokines and Th17/Treg Cells in Human Peripheral Blood Mononuclear Cells in vitro

ABSTRACT

Short-chain fatty acids (SCFAs) have been recognized as mediators of immune responses, including pathways of cytokine production. In this study, we investigated the immune-regulatory effects of SCFAs on human peripheral blood mononuclear cells (PBMCs) from buffy coat of healthy donors. PBMCs were exposed to varying concentrations of individual SCFAs or of their mixtures of acetate, propionate and butyrate. The productions of interleukin (IL) IL-1β, IL-2, IL-6, IL-10, IL-17, IL-21, IL-23 and transforming growth factor beta 1 (TGF-β1) were assessed. T cell differentiation after exposure to SCFAs was also examined. Compared with lipopolysaccharide (LPS)-stimulated cells (controls), SCFAs slightly decreased TGF-β1 production and reduced IL-6 production; butyrate was more effective than acetate or propionate. SCFAs particularly butyrate caused the induction of CD4+CD25+ regulatory T cells (Treg) rather than Th17 cells. SCFAs may up-regulate the production of anti-inflammatory cytokines in PBMCs, resulting in the induction of CD4+CD25+ Treg cells.

KEYWORDS:

• Acetate
• butyrate
• cytokines
• human peripheral blood mononuclear cells
• propionate
• short-chain fatty acids
• T helper cells
• Th17 and CD4⁺CD25⁺ Treg cells

Acknowledgment

We thank the Australian Red Cross Services for their supply of blood products.

Declaration of interest

The authors report no conflicts of interest.

Funding

Author Miloud Asarat has received write-up scholarship from Victoria University for this work. The work was financially supported by College of Health and Biomedicine, Victoria University.

Additional information

Funding

Author Miloud Asarat has received write-up scholarship from Victoria University for this work. The work was financially supported by College of Health and Biomedicine, Victoria University.