(F05) Fucoidan Increases Porcine Neutrophil Extracellular Trap Formation Through Tumor Necrosis Factor-alpha

Abstract:

Background: Fucoidan which is sulfated polysaccharide extracted from brown seaweed has a wide variety of biological activities. Neutrophil extracellular traps (NETs) formation is an immune response for the invasion of microbes. Neutrophils release granule protein and chromatin that together form extracellular fibers that bind pathogens.
Hypothesis/

Objectives: To examine the effect of fucoidan on NET formation of porcine peripheral blood polymorphonuclear cells (PMNs)
Animals: Clinically healthy 6-month-old pigs were included as donors for peripheral blood mononuclear cells (PBMCs).

Methods: The NET formation was measured by fluorescence microplate reader. The production of tumor necrosis factor (TNF)-α in the culture supernatants from peripheral blood mononuclear cells (PBMCs) was measured by ELISA method.

Results: Fucoidan itself did not cause any direct effect on NET formation. However, NET formation of PMNs were increased by the culture supernatant from PBMCs treated with fucoidan. The NET formation of PMNs were also enhanced by treatment with recombinant porcine (rp) TNF-α. The ability of the culture supernatant from fucoidan treated PBMCs to stimulate the NET formation on porcine PMNs was inhibited by addition of goat anti-rp TNF-α polyclonal antibody (pAb; IgG) prior to the culture. NET formation of rp TNF-α was also suppressed by goat anti-rp TNF-α pAb. The level of TNF-α in culture supernatant from PBMCs was increased by treatment with fucoidan.
Conclusion and clinical importance: These results suggested that fucoidan has an immunoenhancing effect on the NET formation of porcine PMNs, which is mediated by TNF-α released from fucoidan-treated PBMCs.