Figure 4.

Oral Tat-Smad7 treatment reduced leukocyte infiltrate in irradiated tongue tumors. (A, D) Representative images of CD45, F4/80 and Ly6G staining in FaDu tumors (A) and UM-SCC-1 tumors (D). K5 antibody was used to counterstain epithelial cells and DAPI was used to counterstain nuclei for CD45 staining. Note that tumor cells after irradiation had more non-specific staining in F4/80 than in non-irradiated tumors (Supplementary Fig. 4). Quantification of F4/80⁺ macrophages in panels C and F is based upon staining intensity and morphology (indicated by yellow arrows, A and D). Black arrows in Ly6G vehicle panel in (A) point to a few remaining Ly6G⁺ cells which were absent in Tat-Smad7 treated tumor. Scale bars = 100 μm for all sections. (B, C) Quantifications of CD45⁺ and F4/80⁺ cells in FaDu tumors. (E-G) Quantifications of CD45⁺, F4/80⁺ and Ly6G⁺ cells in UM-SCC-1 tumors. Immune cells were quantified (mean ± SEM) per mm² tumor area. P values were determined by Student’s t test.