FIG. 5.

NOD1 controls the growth of L. monocytogenes in BMM. (A and B) NOD1^−/− and WT BMM in triplicate wells were incubated with L. monocytogenes at a multiplicity of infection (MOI) of 0.2 (A) or 2 (B) and lysed at the indicated time points after infection, and the numbers of L. monocytogenes CFU in the BMM lysates were determined. Two independent experiments were performed, and the results of one of them are shown. (C) NOD1^−/− and WT BMM were infected with L. monocytogenes at the indicated multiplicities of infection. After 1 h, cells were extensively washed and lysed, and the numbers of CFU were determined. (D) NOD1^−/− and WT BMM were incubated with 100 U recombinant IFN-γ (BD, Pharmingen) 18 h before infection with L. monocytogenes at a multiplicity of infection of 0.2. One hour after infection cells were extensively washed, and IFN-γ was replenished. Cells were lysed at the indicated time points after infection, and the numbers of L. monocytogenes CFU in the BMM lysates were determined. *, P < 0.05 for a comparison with WT mice (Student's t test), indicating a significant difference. (E and F) NO₂⁻ levels in culture supernatants of BMM incubated with 100 U IFN-γ 18 h before incubation with HKL (multiplicity of infection, 10:1), of BMM incubated with IFN-γ, or of BMM incubated with HKL alone 24 h (E) and 48 h (F) after addition of the bacterial lysate.