Figure 4.

C-type lectin receptors and notably dectin-1 bind mushroom compounds. Dendritic cells were pre-incubated with either the chelator EGTA or the low molecular weight soluble β-glucan laminarin followed by stimulation with mushroom compounds. The effect of EGTA and laminarin was assessed by measuring the effect on the TNF-α response. EGTA reduced the TNF-α response to 5–10% of the original response and laminarin showed an inhibition to 40–75%. The effect of EGTA indicates that this class of PRRs plays an important role in DC stimulation because C-type lectin receptors (CLRs) are calcium dependent. Laminarin is a dectin-1 antagonist and shows that this CLR is involved in the binding of mushroom compounds.