Unopsonized and opsonized CS2 IE induce comparable pro-inflammatory cytokine mRNA expression. MDM cultured in 24-well plates were primed with IFN-γ for 48 hr, and then exposed to purified CS2 IE opsonized with PPS(●) or without opsonization (○) at an IE to MDM ratio of 20:1. RNA extracts were prepared after the indicated times and analysed by qPCR for cytokine and GAPDH mRNA content as described in Methods. Cytokine mRNA was quantified using the comparative threshold method and expressed relative to levels at t=0. Values represent the median [± IQR] for six experiments using MDM prepared from separate donor monocytes. No significant differences between cells exposed to opsonized or unopsonized IE were observed at any time point (p<0.05, Mann Whitney U test comparing IE with IE-IgG at each time point).