Figure 1. Quantification of cardiolipin (CL) in pneumonia.

a. Panel a depicts the median (gray line) and distribution (black circles) of CL levels in tracheal aspirates from subjects with non-pulmonary critical illness (NPCI, n=five), pneumonia (PNA, n=17), and congestive heart failure (CHF, n=six). Groups were compared by Kruskal Wallis test (P=0.0007) followed by post hoc Wilcoxon Rank Sum analysis with Bonferroni correction for multiple testing b. C57BL/6 mice (three control, five H. influenzae, four E.coli) were infected intratracheally (i.t.) with E. coli (1 ×10⁶ CFU/mouse) or H. influenzae (2 × 10⁸ CFU/mouse). Mice were euthanized 48 h (E. coli) or 72 h (H. influenzae) later, lungs lavaged, and processed for CL assay. Inset: Mice (six/group) were given HCL (pH 1.5, 2 ml/kg i.t.) prior to being euthanized 30 min later for analysis of CL. c. Primary type II lung epithelia (from n=ten mice) were cultured with [³H]-CL containing the commercial surfactant, Infasurf, for 2 h at 37 °C in the presence or absence of E. coli (MOI=100) or H. influenzae (MOI=10) and cellular CL uptake was determined. In (b-c), ^** represents means ± S.D. with P<0.01, and ^***represents P<0.001 vs. control as determined by one-way ANOVA analysis.