FIG. 4.

CD47 blockade promotes TAM accumulation in a transgenic mouse model of ATC. (A) H&E staining and IHC for CD47, CD68, and F4/80 in FFPE tumor samples from Thyro-DT mice. One representative image of tumors from eight mice is shown for each staining. Scale bars: 200 μm. (B–G) Three months after transgene induction, tumor-bearing Thyro-DT mice were divided in two groups with similar tumor size and treated with either 500 μg anti-CD47 mAb (n = 4) or antibody dilution buffer (n = 5) by i.p. injection twice a week. Tumor growth was measured by ultrasound every two weeks and normalized to baseline before start of treatment. After 10 weeks of treatment, mice were sacrificed, and spleens and thyroids were analyzed by FACS. (B–D) Frequencies of (B) CD4⁺ T cells, (C) CD8⁺ T cells, and (D) CD11b⁺ F4/80⁺ macrophages were determined in the spleen. (E) MFI of CD80 expression on splenic CD11b⁺ F4/80⁺ macrophages. (F and G) The frequencies of tumor-infiltrating (F) total CD45⁺ cells and (G) CD11b⁺ macrophages were determined in the thyroids of Thyro-DT mice. Data from one thyroid lobe per mouse are shown. Statistics: Student's t-test. *p < 0.05. n.s., not significant.