Figure 1

MyD88-dependent signals are essential for C. koseri containment during CNS infection. MyD88 WT and KO mice (triangles and circles, respectively; 3-4 per group) received intracerebral injections of C. koseri (3.4 × 10⁴ cfu), whereupon the number of viable bacteria in either the injected (A) or contralateral (B) hemispheres were determined at 12 or 24 h post-infection. Bacterial burdens are expressed the colony forming units (cfu) of C. koseri per gram of wet tissue weight (each data point represents an individual animal) and significant differences between MyD88 KO and WT mice are denoted by asterisks (*, t-test, p < 0.05). Identification of C. koseri localization by Gram staining revealed heightened numbers of extracellular bacteria (arrows, 100×) associated with the infected hemispheres of MyD88 KO (D) compared to WT (C) animals at 24 h post-infection. Results are representative of three independent experiments with a total of 3-6 mice/group/study.