Fish oil differentially regulates B cell and dendritic cell activation in response to a T‐independent antigen

Abstract

Fish oil (FO) has clinical utility for regulating immunity. The functional consequences of FO on B cells and dendritic cells (DC) are poorly studied, especially at the animal level. Here we tested the effects of FO, modeling human pharmacological intake, on murine ex vivo B cell and DC activation in response to the T‐independent antigen lipopolysaccharide (LPS). LPS stimulation of B cells increased CD69 surface expression and enhanced secretion of IL‐6, TNFα and IFNγ with FO. In comparison, LPS stimulation of DCs resulted in reduced CD80 surface expression and TNFα secretion with FO, which was associated with decreased phagocytosis of E. coli bioparticles. To reconcile differences between cell types, we measured the formation of plasma membrane lipid microdomains. Although FO promoted an increase in EPA and DHA levels, we discovered differential effects on the ability of B cells and DCs to cluster lipid microdomains. Overall, this study shows FO differentially regulates the activation of B cells and DCs in response to LPS, which may be due to differences in underlying membrane organization. Our data highlight the possibility that FO can be used to exert both immune enhancing and immunosuppressive effects, depending on the cellular target.Grant Funding Source: NIH R15AT006122 (to S.R.S.)