Lack of Proinflammatory Cytokine Interleukin-6 or Tumor Necrosis Factor Receptor-1 Results in a Failure of the Innate Immune Response after Bacterial Meningitis

Figure 1

Mortality after pneumococcal meningitis. Wild type (WT), TNFR1-, IL-6, or TNFR1-IL-6 knockout (KO) mice were infected by injection of 10⁴ colony-forming units (CFU) of Streptococcus pneumoniae D39 (type 2) strain in the subarachnoid space. (a) Comparison of survival times revealed that WT mice lived significantly longer (WT, ; TNFR1-KO, ; IL-6-KO, ; TNFR1-IL-6-KO, ; median with percentile; Mann-Whitney test; for TNFR1- or TNFR1-IL-6-KO versus WT and for IL-6-KO versus WT). (b) Mortality was significantly increased in TNFR1- and/or IL-6-KO animals (Kaplan-Meier-Curve; for TNFR1- and TNFR1-IL-6-KO, for IL-6-KO versus WT; log-rank test).

(a)

(b)