Exopolysaccharide from Trichoderma pseudokoningii induces macrophage activation

Carbohydr Polym. 2016 Sep 20;149:112-20. doi: 10.1016/j.carbpol.2016.04.093. Epub 2016 Apr 26.


In this study, we evaluated the immunomodulatory activity of an exopolysaccharide (EPS) derived from Trichoderma pseudokoningii and investigated the molecular mechanism of EPS-mediated activation of macrophages. Results revealed that EPS could significantly induce the production of nitric oxide (NO), tumor necrosis factor (TNF)-α and interleukin (IL)-1β and enhance phagocytic activity in RAW 264.7 cells. Immunofluorescence staining indicated that EPS promoted the nuclear translocation of nuclear factor (NF)-κB p65 subunit. Western blot analysis showed that EPS increased the expression of inducible nitric oxide synthase (iNOS) protein, the degradation of IκB-α and the phosphorylation of mitogen-activated protein kinases (MAPKs). Furthermore, pretreatment of RAW 264.7 cells with specific inhibitors of NF-κB and MAPKs significantly attenuated EPS-induced TNF-α and IL-1β production. EPS also induced the inhibition of cytokine secretion by special antibodies against Toll-like receptor-4 (TLR4) and Dectin-1. These data suggest that EPS from Trichoderma pseudokoningii activates RAW 264.7 cells through NF-κB and MAPKs signaling pathways via TLR4 and Dectin-1.

Keywords: Dimethyl sulfoxide (PubChem CID: 679); Exopolysaccharide; Immunomodulation; Lipopolysaccharide (PubChem CID: 11970143); MAPKs; Macrophages; NF-κB; Nitric oxide (PubChem CID: 145068); Trichoderma pseudokoningii.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Survival / drug effects
  • Fungal Polysaccharides / chemistry
  • Fungal Polysaccharides / isolation & purification
  • Fungal Polysaccharides / pharmacology*
  • Gene Expression Regulation, Enzymologic / drug effects
  • Immunologic Factors / chemistry
  • Immunologic Factors / isolation & purification
  • Immunologic Factors / pharmacology*
  • Interleukin-1beta / metabolism
  • Macrophage Activation / drug effects*
  • Macrophages / cytology
  • Macrophages / drug effects
  • Macrophages / immunology
  • Macrophages / metabolism
  • Mice
  • Mitogen-Activated Protein Kinases / metabolism
  • NF-KappaB Inhibitor alpha / metabolism
  • NF-kappa B / metabolism
  • Nitric Oxide / biosynthesis
  • Nitric Oxide Synthase Type II / metabolism
  • Phagocytosis / drug effects
  • Phosphorylation / drug effects
  • Proteolysis / drug effects
  • RAW 264.7 Cells
  • Trichoderma / chemistry*
  • Tumor Necrosis Factor-alpha / metabolism


  • Fungal Polysaccharides
  • Immunologic Factors
  • Interleukin-1beta
  • NF-kappa B
  • Tumor Necrosis Factor-alpha
  • NF-KappaB Inhibitor alpha
  • Nitric Oxide
  • Nitric Oxide Synthase Type II
  • Mitogen-Activated Protein Kinases