Fig. 7

Fig. 7 Levofloxacin and bacitracin act synergistically in vivo in a zebrafish embryo meningitis model.

A Experimental set up. S. pneumoniae was injected into the hindbrain ventricle of zebrafish larvae at 2 days post-fertilization. Zebrafish were treated at 1 hour post injection with: DMSO vehicle controls (group 1), BAC injected into the bloodstream and DMSO vehicle control added to the water (group 2), LEV added into the water and DMSO vehicle control injection (group 3), or a combination of both LEV added to the water and BAC injection (group 4). B Survival curves of zebrafish embryos injected with ~300 CFUs of S. pneumoniae D39V. Zebrafish embryos were treated with DMSO (control), LEV, BAC or a combination of both BAC and LEV. The data represent the mean ± SEM of three biological replicates with 15 larvae per group (n = 45 in total/group); ns = not significant, *p = 0.0064, ****p < 0.0001; determined by Log-rank test. C Survival curves of zebrafish embryos injected with ~300 CFUs of fluoroquinolone-resistant S. pneumoniae strain FQR_25191. Zebrafish embryos were treated with DMSO (control), LEV, BAC or a combination of both BAC and LEV. The data represent the mean ± SEM of three biological replicates with 15 larvae per set (n = 45 in total/group); ns not significant, *p = 0.0437; determined by Log-rank test.