Figure 6

Lp-PLA2-/- mice had similar degree of airway inflammation, circulating and local IgE but attenuated IL-4 and IL-5 release in the BAL fluid when compared with WT mice. (A): Representative photomicrographs of H&E stained sections from formalin fixed and paraffin embedded lung tissue of each group. (B): Inflammation was semi-quantitatively assessed (median shown; n=3-11). The following inflammation score was used: (0-0.5): no infiltrates, intact lung structure. (1-1.5): <10 inflammatory cells/field. (2-2.5): Peri-bronchial/peri-vascular infiltrates. (3-3.5): peribronchial/vascular cuffing with parenchymal extensions. The entire tissue section was scored. (C-D): Total IgE and anti-Af specific IgE was measured by ELISA from serum and BAL samples of either non-sensitized (n=3) or Af-sensitized (n=11-16) mice. All animals received a single Af challenge. Maxisorp 96-well plates were used and IgE was detected by HRP-conjugated anti-mouse IgE. Data presented as ng/ml for total IgE with group median (C) or OD450 nm with group median for anti-Af specific IgE (D). The measurements were performed in duplicates. (D left panel): A strong positive correlation is shown between serum Lp-PLA2/PAF-AH levels (ratio over naïve serum ctr) and Af specific serum IgE levels in WT mice (but not Lp-PLA2-/- mice, not shown), sensitized and challenged with Af. (E-F): Cytokine and chemokine levels in cell-free BAL supernatant were measured by a Luminex assay. (E): Correlation of Th2-related mediators with IL-4 (on the y axis). The points represent log10 transformed individual values. (F): Cytokine profiles shown among 4 groups, n=3-7. Data are presented as mean ± SEM, pg/ml. Student’t test *p<0.05.