a, Timeline for bioluminescent Streptococcus pneumoniae Xen10 meningitis. b, Bioluminescence imaging (BLI) of sham controls or mice after intracisternal injection of S. pneumoniae Xen10 (scale: 2 cm). c, Bacterial load measured by BLI (mean ± SD; n=11 sham, 6 12hr, 12 36 hr, 24 48 hr; P values represent a Kruskal-Wallis test with Dunn’s multiple comparisons test). d, Bacterial colony forming unit (CFU) assay from blood and CSF at 48 hours (mean ± SD; n=8; P value represents a Mann-Whitney two-sided rank test). e, Skull channels following tissue-clearing (171 μm, 3 μm/step with 57 steps) (scale: 50 μm, n=4 mice from 2 experiments). f, Tissue-clearing scheme. g, Representative z-stack images of sham controls (248 μm, 0.75 um/step with 331 steps) and mice after IC GFP+
Streptococcus pneumoniae JWV500 (267 μm, 3 μm/step with 89 steps) . CD31/Sca1 labels vasculature and osteosense marks bone (n=4 sham, 6 meningitis; scale: 100 μm). h, Three-dimensional reconstructions highlighting skull channels (arrows) and marrow bacteria (green arrows). Scale: 100 μm, 50 μm and 35 μm; data pooled from 3 independent experiments. Upper row indicates control mouse without bacterial injection, lower row indicates a mouse 48 hours after induction of meningitis.