FIGURE 4.

Netrin‐1 deletion in myeloid cells exacerbates LPS‐induced lung injury. A, Mortality of mice with conditional deletion of Ntn1 in myeloid cells (Ntn1^loxp/loxp LysM Cre) compared with LysM Cre control mice in LPS‐induced lung injury (n = 10 mice in LysM Cre group, n = 12 mice in Ntn1^loxp/loxp LysM Cre group, Kaplan‐Meier curves, log‐rank test). B) Fractional weight loss in Ntn1^loxp/loxp LysM Cre mice compared with LysM Cre controls (n = 10‐12 mice per group, Bonferroni‐adjusted Welch’s or unpaired t test). C, Pulmonary edema was assessed by enzyme‐linked immunosorbent assay (ELISA) quantification of bronchoalveolar lavage fluid (BALF) albumin in Ntn1^loxp/loxp LysM Cre and LysM Cre mice with LPS‐induced lung injury at indicated time points (n = 5‐7 mice per group, Bonferroni‐adjusted unpaired t test). D, Quantification of BAL neutrophils in Ntn1^loxp/loxp LysM Cre and LysM Cre mice with LPS‐induced lung injury at indicated time points (n = 5‐7 mice per group, Bonferroni‐adjusted unpaired t tests). E, F, ELISA quantification of inflammatory cytokines, IL‐1β and IL‐6, in BALF collected from Ntn1^loxp/loxp LysM Cre and LysM Cre mice with LPS‐induced lung injury at indicated time points (n = 5‐7 mice per group, Bonferroni‐adjusted unpaired t test). G and H, Representative sections and lung injury scoring of hematoxylin and eosin stained lung tissue collected from Ntn1^loxp/loxp LysM Cre and LysM Cre mice 3 days after onset of LPS‐induced lung injury (4× magnification, n = 5‐13 mice per group, unpaired t test). All data are represented as mean ± SD. *P‐value < .05