Figure 3.

Effect of infection by wild type N. meningitidis on endogenously produced SNO in activated J774.2 cells. At t = 0 h, duplicate wells of J774.2 cells were activated with 1 μg/ml LPS and 1000 U/ml rmIFN-γ for 18 h and then infected with a suspension of log-phase wild-type N. meningitidis in fresh medium at MOI 10 or 100 for 2 h (t=20 h) (A) or 4 h (t=22 h) (B). Lysates were produced using SNO-compatible lysis buffer plus 2% saponin. SNO content was determined by duplicate injection into I₃⁻ reaction mixture linked to ozone-based chemiluminescence and normalized to the protein concentration of the lysate. Data are presented as SNO concentration (pmol SNO/mg protein). Bars denote means + se. *P < 0.05, ***P < 0.001; ANOVA with Tukey’s multiple comparisons test.