Figure 4.

CCL5 is secreted from tumours and induces alternative macrophage polarization. (A) CCL5 in 4T1-metastatic and 67-NR-nonmetastatic breast cancer cell culture supernatant was quantified by ELISA. Raw 264.7 macrophages were treated with recombinant protein CCL5 (3 pg mL⁻¹) for 24 h and (B) ANXA1 or (C) Arg1 expression was quantified by RT-qPCR. Macrophages were treated with 4T1-conditioned media for 24 h in the presence and absence of CCL5-blocking antibody (1 µg mL⁻¹) and (D) Arg1 or (E) ANXA1 expression was quantified by RT-qPCR. BMDM were isolated from WT and ANXA1^−/− mice and treated with recombinant protein CCL5 (3 pg mL⁻¹) for 24 h. Arg1 expression was quantified by RT-qPCR (F). Data shown are mean ± SD (N = 4). *P ≤ 0.05, **P ≤ 0.01, ANOVA.