IL13 and melanoma: At higher doses of SIM (2–6 μM), B16.F10 cell proliferation was overall significantly reduced when co-cultured with IL-13-LCL-SIM-treated M2 macrophages compared to LCL-SIM-treated M2 macrophages (p < 0.05), suggesting that the targeted high-affinity treatment induced a better modulation of the capacity of M2 macrophages to support melanoma cell growth (Figure 2A).