FIG. 5.

Time course of increase in nitric oxide production (A) and iNOS expression (B) by murine microglial cells treated with S. suis. The heat-killed S. suis WT or CPS⁻ strain (1 × 10⁹) was incubated with microglia for 6, 12, 24, and 48 h. (A) Microglial supernatants were collected to measure nitric oxide production by the Griess reaction method. The data are expressed as the means plus SEM (in μM/ml) of three independent experiments. *, P < 0.05, indicating significant differences versus WT S. suis. n. i., noninfected cells. (B) Representative Western blot analysis of murine microglial extracts using an iNOS-specific antibody. Blotting with anti-α-actin antibody was used as a loading control.