Figure 6.

Negative correlation between tumor-infiltrating M2-like TAMs, MDSCs and Tregs after LTF-IC treatment in TG mice. B16 melanoma-bearing WT and hCD32a-TG mice (n=3) were i.p. treated with or without (PBS), LTF, M860 or LTF-IC (10 mg kg⁻¹) on days −1, 7 and 14. The mice were sacrificed, on day 18, for solid tumor tissues. cells thus isolated were subjected to multicolor immunofluorescence staining and FACS analysis, gating on populations of (A) CD45⁺F4/80^-CD11b⁺Gr-1⁺ (MDSC) and (B) CD4⁺Foxp3⁺ (Treg) cells. Melanoma samples from each mouse were individually assessed. in addition to representative dot plots presented, the results (mean+SD) are also shown as percent MDSCs and Trges among the CD45⁺ and CD4⁺ population, respectively, in the bar graphs on the right. (C) C57BL/6 mice (n=3) bearing B16 melanoma were intratumorally injected with either PBS, or LTF-IC-treated WT-/TG-B16-TAMs (M2 +LTF IC) or WT/TG mouse bone marrow-derived M1 macrophages (M1) every 2 days (1×10⁵ cells per inoculation). Mice were sacrificed on day 18 and tumor tissue-extracted cells were subjected to multicolor immunofluorescence staining and FACS analysis, gating on CD45⁺F4/80^-CD11b⁺Gr-1⁺ (MDSC) and CD4⁺Foxp3⁺ (Treg) cells. The results (mean+SD) are expressed as percent MDSCs and Tregs among the CD45⁺ or CD45⁺CD3⁺CD4⁺ populations, respectively. *P<0.05, **P<0.01, ***P<0.001. hCD32a, human CD32a; IC, immunocomplex; LTF, lactoferrin; PBS, phosphate-buffered saline; TAM, tumor-associated macrophage; TG, trangenic; WT, wild type.