Loss of MMP-8 affects MMTV-PyMT neutrophil, but not macrophage, infiltration and expression of pro-inflammatory mediators.

A) Number of macrophages/mm2 and neutrophils/mm2 in early and late stage tumors as determined by staining for F4/80 and Ly6B.2, respectively. The number of mice used for analyses of macrophage and neutrophil infiltration respectively were at 6 weeks: Mmp8 wild-type (WT, n = 5, 5), heterozygote (HET, n = 4,3) and null (KO, n = 2,3); 8 weeks: Mmp8 wild-type (WT, n = 4,5), heterozygote (HET, n = 6,5), null (KO, n = 4,5) and at 10 weeks: Mmp8 wild-type (WT, n = 5,5), heterozygote (HET, n = 5,5) and null (KO, n = 4,4).* p < 0.05, ** p < 0.01. One representative image of macrophage and neutrophil staining is shown for each genotype at 10 weeks of age. B) Relative RNA expression of macrophage marker CD68, IL-6 and CXCL5/LIX, normalized to 18S rRNA, throughout disease progression (6–14 weeks of age).