Fig 1.
Transmission electron microscopy (TEM) analysis of RAW264.7 cells infected with S. aureus.
The RAW264.7 cells were either not infected or infected with S. aureus alone or in combination with PG for two different time points. The upper panel shows the pictures by TEM after 1 h of S. aureus infection, while lower panel depicts the same after 24 h. Bar = 2 μm. Black arrow indicated the internalized S. aureus.
Fig 2.
The gene expression profile microarray analysis.
The gene expression profile analysis was performed using mouse DNA microarray chip using RNA isolated from RAW264.7 cells either treated with S. aureus or S. aureus + PG. Non-treated RAW264.7 cells were used as a control. Red signal indicates up-regulation of gene expression, while green signal depicts down-regulation.
Fig 3.
The expressions of important immune genes in RAW264.7 cells after the challenge.
At 1 h after challenge with heat-inactivated S. aureus and heat-inactivated S. aureus + PG, the expression profiles of Jak2, Stat3, Stat5a, Csf1, Cish, IL-1a, IL-1b, Nfkb1, TNF-α and Bcl2 genes in RAW264.7 cells were characterized by quantitative real-time PCR. The GAPDH gene was used as a control. Statistically significant differences between treatments were indicated with asterisks (**, P<0.01).
Table 1.
Fold change in the expression profiles of the Toll pathway related genes induced by S. aureus and S. aureus +PG treatments.
Table 2.
Fold change in the expression profiles of some important immune function related genes induced by S. aureus and S. aureus + PG treatments.
Table 3.
Fold change in the expression profiles of the apoptotic pathway related genes induced by S. aureus and S. aureus +PG treatments.
Fig 4.
Flow cytometry based measurement of apoptosis in RAW264.7 cells, induced with S. aureus and S. aureus +PG treatment for 12 hours.
Panel, A represents the apoptosis signal in the control cells. Panel, B represents the S. aureus induced apoptosis; and Panel, C depicts the S. aureus +PG induced apoptosis in RAW264.7 cells. Panel, D represents the mean percentage of apoptotic cells measured from three independent experiments. Double asterisks indicate a significant difference (P<0.01) between the samples.