Fig. 5.

Neutralization of IL-1β or CCL2 inhibits the lung tumor-promoting effect of HDM. A Representative pictures of H&E-stained lung sections of Kras.^G12D mice treated i.n with VEH or HDM and i.p with a neutralizing anti-IL-1β, anti-CCL2, or with the isotype control (ctrl) Ab as shown in Supplemental Fig. 5A. VEH + ctrl Ab (n = 6), HDM + ctrl Ab (n = 8), VEH + IL-1β Ab (n = 7), and HDM + IL-1β Ab (n = 8), VEH + CCL2 Ab (n = 7), and HDM + CCL2 Ab (n = 9). Scale bars, 2 mm. B Tumor multiplicity calculated on H&E-stained sections as shown in A. C Tumors on H&E-stained sections as shown in A were classified into three grades (Grade 1, AAH and EH; Grade 2, AD; Grade 3, AC) and each grade was expressed as a percentage of the total. D Representative pictures of H&E-stained lung sections of WT and Il1b KO mice treated i.n with VEH or HDM and with urethane as shown in Fig. 1A. WT + VEH (n = 7), WT + HDM (n = 8), Il1b KO + VEH (n = 8), and Il1b KO + HDM (n = 10). Four lobes per mouse are shown. Arrowheads indicate tumors. Scale bars, 1 mm. E Two selected ROIs on the H&E-stained lung sections shown in D. ROI#1 shows an AC with enlarged nuclei, prominent nucleoli, and scattered mitotic figures (inset) found in one lung lobe of a WT mouse treated with urethane and HDM. ROI#2 shows an AD of the papillary type with uniform nuclei (inset) found in one lung lobe of an Il1b KO mouse treated with urethane and HDM. Scale bars, 0.1 mm (ROI#1 and 2) and 50 μm (ROI#1 and 2 insets). F Tumor multiplicity and G) Tumor area calculated on H&E-stained sections as shown in D. Data are representative of one experiment conducted in two to five independent cohorts of mice pooled together (A–C ctrl and CCL2 Abs, and D–G) or conducted twice independently (A–C IL-1β Ab) and are presented as mean ± SEM. Statistical significance was assessed by one- (B, F, and G) or two-way (C) ANOVA with post hoc Bonferroni’s test. n.s: non-significant, * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001