Figure 5.

Wnt inhibition reactivates immune responses in IDH1^WT GBM allografts. (a) Representative [¹⁸F]DPA714-PET/CT images of mouse brains bearing IDH1^WT GBM allografts at 7 and 14 days after treatment with the Wnt/β-catenin inhibitor Wnt-C59 (15 mg/kg). Right panel, intratumoral SUVmean at 30 min post [¹⁸F]DPA714 injection at 14 days (n = 4). Flow cytometric analysis of immunostimulatory (CD16/32⁺) and immunosuppressive (CD206⁺ CD16/32⁺) subtypes among CD11b⁺ CD45⁺ Iba1⁺ CD49d⁻ microglia (b), CD8⁺ T cells and CD4⁺ T cells among CD45⁺ CD3⁺ cells (c), and CD4⁺ FOXP3⁺ T cells among CD45⁺ CD25⁺ CD8⁻ cells (d) in untreated and Wnt-C59 (7.5 or 15 mg/kg)-treated model mice (n = 4). (e) Immunoblots showing CD163, Wnt3a, GSK-3β and β-catenin protein expression in tumor tissues isolated from untreated and treated model mice. (f) mRNA expression of IFN-γ, iNOS, TGF-β and IL-10 in the above samples (n = 3). In panel a, values are shown as Mean±SEM. In panel b, c, d and f, values are shown as Mean±SD. Student’s t-test. *p < .05; **p < .01 and ***p < .001