[ODP-167] Effect of zymosan on poly(I:C)-induced production of proinflammatory cytokines and type I interferon
Objective: Pretreatment with zymosan upregulated proinflammatory cytokine production by mouse macrophage-like J774.1 cells incubated with a ligand of Toll-like receptor (TLR) 7, but not interferon (IFN)-β production. In this study, we investigated whether zymosan or curdlan augmented production of IL-6, MCP-1, TNF-α, and IFN-β by J774.1 cells incubated with poly(I:C), a ligand of TLR3 and retinoic acid-inducible gene-I (RIG-I).
Methods: J774.1 cells were pretreated with or without zymosan, a TLR2 and dectin-1 ligand, curdlan, a dectin-1 ligand, or Pam3CSK4, a TLR2 ligand in 96-well flat-bottomed plates for 24 h. Cells were then washed and incubated with 1 μg/ml poly(I:C) for 24 h. Culture supernatants were analyzed by ELISA for secreted mouse IL-6, MCP-1, TNF-α, and IFN-β. Expression of RIG-I and caspase-11 was analyzed by western blotting.
Results and Discussion: Pretreatment with zymosan augmented poly(I:C)-induced production of IL-6, MCP-1, TNF-α, and IFN-β by J774.1 cells. In addition, similar results were shown in pretreatment of cells with curdlan. Treatment with zymosan or curdlan for 24 h up-regulated RIG-I expression by J774.1 cells. In addition, poly(I:C) significantly activated caspase-11. These results suggest that zymosan or curdlan augments poly(I:C)-induced production of proinflammatory cytokine and IFN-β by J774.1 cells via enhancing RIG-I expression.