Figure 1. Mek1^flLysM^Cre reduces alveolar macrophage MEK1 and decreases proinflammatory gene expression following LPS stimulation.

(A) Protein lysates from alveolar macrophages were recovered from naive female and male mice by bronchoalveolar lavage (BAL) and were used to detect total MEK1, MEK2, and GAPDH levels by Western blot. (B) Quantification by band densitometry revealed significant reduction in MEK1 without changes in MEK2 in Mek1^flLysM^Cre mice compared with Mek1^fl mice. Data points show values derived from an individual mouse (n = 4 for Mek1^fl and n = 10 for Mek1^flLysM^Cre), and the bars represent the mean ± SEM. (C) Quantitation of alveolar macrophages recovered from BAL of naive Mek1^fl mice (n = 4 female, n = 5 male) and Mek1^flLysM^Cre (n = 5 female, n = 5 male) reveal no differences in the total number of cells recovered. (D) Alveolar macrophages collected from the same mice as in C were allowed to attached to tissue culture plates and were stimulated with 50 ng/mL E. coli LPS for 4 hours. RNA was isolated and cDNA used as the template in qPCR reactions to measure proinflammatory gene expression. Relative Cxcl1, Il1b, Nos2, Ccl5, Ifit1, and Cxcl10 were compared to Hprt, and data are normalized to Mek1^fl samples. Data points show values derived from an individual mouse and the bars represent the mean ± SEM. In A–D, statistical analysis used an unpaired t test. **P < 0.01, ***P < 0.001, ****P < 0.0001; ns, not significant.