Figure 8.

KIT-dependent mast cells competent in interleukin-1β are required for lung adenocarcinoma.

A Left: Representative cytocentrifugal specimens of toluidine blue-stained bone marrow-derived cells from WT and Il1b-/- mice before (top) and after one-month incubation with 100 μg/mL interleukin (IL)-3 and 100 μg/mL KIT ligand (KITL) or with 100 μg/mL IL-3 alone (bottom). Note the >95% metachromasia of bone marrow-derived mast cells (BMMC) of different maturation stages after treatment. Right: Representative cytocentrifugal specimen of toluidine blue-stained BMMC mixed with LLC cells at 1:50 ratio before experiments. B, C LLC cells alone or co-cultured with BMMC from (A) were assessed for in vitro cellular proliferation by MTT reduction and for in vitro cell migration by scratch assay. (B) Representative scratch assay images at experiment start and conclusion. (C) Summary of data from n = 5–6 independent experiments expressed as mean±SEM with two-way ANOVA P values. ns, *, and ***: P> 0.05, P< 0.05, and P< 0.001, respectively, for comparison with DMEM control (c) by Bonferroni post-tests. D Ccr2 gene-deficient mice (n = 6/group) received 10⁶ subcutaneous LLC cells alone or mixed with BMMC at 50:1 ratio and were followed for a month by weekly measurements of three vertical primary tumor diameters and calculation of flank tumor volume. Summary of data from n = 6 mice/group expressed as mean±SEM with two-way ANOVA P value. ns and ***: P> 0.05 and P< 0.001, respectively, for comparison with DMEM control (c) by Bonferroni post-tests.