Fig. 1.

γ-PGA induced the activation of macrophage by MyD88-dependent and -independent pathways. BMDMs (1 × 10⁶ cells/ml) isolated from wild-type or MyD88^−/− mice were stimulated with 100 ng/ml LPS or 1 mg/ml γ-PGA in the presence or absence of 10 μg/ml polymyxin B (PMB) for 24 h. Concentration of TNF-α (a) and IP-10 (b) in the culture supernatants were measured by enzyme-linked immunosorbent assay (ELISA). RAW264.7 cells, murine macrophage cell line, were transiently transfected with siRNA targeting the coding regions of MyD88 (siMyD88) and the control siRNA. The mRNA and protein expression levels of MyD88 of siRNA transfected cells were determined by RT-PCR, fluorescence microscopy (×200) and flow cytometry analysis (c). The RAW264.7 cells transfected with siRNA were treated with 100 ng/ml LPS and 1 mg/ml γ-PGA. The concentrations of TNF-α in the supernatants of siMyD88- or the control siRNA-transfected cells were determined by ELISA (d). Asterisks represent not detected. The results are expressed as mean ± SE of three independent experiments