Water-soluble polysaccharides from Pleurotus eryngii fruiting bodies, their activity and affinity for Toll-like receptor 2 and dectin-1. (15th July 2021)

• Record Type: Journal Article
• Authors: Ellefsen, Christiane Færestrand; Wold, Christian Winther; Wilkins, Alistair L.; Rise, Frode; Samuelsen, Anne Berit C.
• Is Part Of: Carbohydrate polymers. Volume 264(2021)
• Publication Date: 2021-07-15
• Subjects: Pleurotus eryngii -- β-Glucan -- Mannogalactan -- TLR-2 -- Dectin-1; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2021.117991
• Languages: English
• ISSNs: 0144-8617

Abstract

Highlights: Water-soluble polysaccharides were isolated from Pleurotus eryngii fruiting bodies. A 3- O methylated mannogalactan and a branched (1→6)(1→3)-β-d -glucan were the main polysaccharides. Small amounts of (1→3)-α-d -glucan and (1→2)-β-d -mannan were also identified. The polysaccharides fractions modestly induce activation of D2SC/1 cells, and bind and activate human TLR2-TLR6. β-d -glucan containing fractions bind and activate human dectin-1 receptor. Abstract: The mushroom cell wall contains polysaccharides that can activate cells of the innate immune system through receptors such as Toll-like receptors (TLR) and dectin-1. In the present study, Pleurotus eryngii polysaccharide fractions containing a 3- O methylated mannogalactan and (1→3)/(1→6)-β-d- glucans were isolated and extensively characterized by 2D NMR and methylation analysis. Traces of a (1→3)-α-d- glucan and a (1→2)-α-d- mannan were also observed. Affinity for TLR2, TLR2-TLR6 and dectin-1 using HEK-cells expressing the relevant receptor genes was tested. PeWN, containing the 3 -O methylated mannogalactan, was inactive towards TLR2, whereas fraction PeWB, containing more β-glucan, activated the TLR2-TLR6 heterodimer. Activation of the human β-glucan receptor dectin-1 correlated with the amount of β-glucan in each fraction. Nitric oxide and cytokine supernatant levels of D2SC/1 dendritic cells stimulated with the P. eryngii fractions and interferon-γ were low to moderate. The results indicate that the immunomodulatory activity of water-soluble P. eryngii polysaccharide fractions is modest.