Vaping exacerbates key clinical metrics of microbial pneumonia.

(A) Study design. (B) Lung wet/dry ratio of mice pre-exposed to either vaped vehicle or e-liquid and then infected with a sub-lethal dose of Klebsiella pneumoniae. n = 4 mice per treatment group. (C) H&E staining (200X magnification) of lung tissue isolated from vaped vehicle- or vaped e-liquid- treated mice infected with K. pneumoniae. n = 3 mice per group. Arrows indicate alveoli thickening and neutrophil influx. ALI was evaluated and scored to quantify inflammation within tissue sections using an ATS accepted rubric [27]. (D) Inflammatory cytokine analysis of BAL fluid from vaped vehicle- or vaped e-liquid- treated mice infected with K. pneumoniae (compared to the mock control) as performed via Luminex array. Symbols and bars represent the mean ± SEM compared to the mock control (* P<0.05, ** P<0.01, *** P<0.001).