Fig. 5. Ability of mAbs to protect in vivo against A. baumannii BAL 191.

Adult BALB/c mice were intravenously dosed with 10 mg/kg of 1042, 1349, isotype control mAb or left untreated on day -1 and day 0, challenged on day 0 with 5 × 10⁷ CFU A. baumannii isolate BAL 191 and culled 24 h later. Bacterial loads at 24 h in lungs (a), nasal wash (b) and spleen (c) were enumerated to evaluate protection. In a subsequent study, mice intravenously or intranasally dosed with 10 mg/kg of 1416 or isotype control were similarly evaluated for protection using the KL49 isolate BAL 191. Bacterial loads at 24 h in lungs and spleen of intravenously dosed (d, e, f) and intranasally dosed mice (g, h, i) were evaluated. Statistical analysis was performed using a Mann–Whitney test with p shown as a numerical value when p ≤ 0.05. The data presented in (a–c) are a single study (n = 5; n defined as an individual mouse); the data presented in (d–f) represent 2 experiments combined (n = 5 per study, n = 10 total); (g–i) represent a single n = 5 study. Bar represents mean value for each data set.