Targeting tumor-associated macrophages as a novel strategy against breast cancer
J. Clin. Invest. Yunping Luo, et al. 116:2132 doi:10.1172/JCI27648 [Go to this article.]

Figure 1
Legumain is highly expressed on TAMs in the tumor stroma. (A) Legumain expression on TAMs was clearly evident. Tumor-infiltrating macrophages were visualized by H&E staining, as indicated by arrows. Legumain expression is indicated by double staining with anti-legumain Ab (green) combined with anti-CD68⁺ Ab (red). Magnification, ×350. (B) Increased legumain expression on TAMs was confirmed by flow cytometric analyses with double-positive populations of F4/80⁺/CD206⁺ M2 macrophages that were isolated from fresh tumor tissue. (C) Multiple-color flow cytometry demonstrated upregulation of the M2 macrophage marker CD206 on RAW cells after being cultured with IL-4, IL-10, and IL-13 (10 ng/ml). Furthermore, legumain was shown to be highly expressed on F4/80⁺/CD206⁺-positive RAW cells cultured with IL-4, IL-10, and IL-13 (upper panels) compared with wild-type RAW cells (lower panels). (D) Confirmation of legumain expression on RAW cells by Western blotting following stimulation with IL-4, IL-13, and IL-10, either singularly or combined.