Fig. 6
From: Triggering anti-GBM immune response with EGFR-mediated photoimmunotherapy
Characterisation of the syngeneic BL6-NPE-GFP-Luc orthotopic mouse model and immunologic response after PIT treatment. A In vivo axial T2-weighted MRI image acquired at 1 T and corresponding ex vivo photography and fluorescence image of the orthotropic BL6-NPE-GFP-Luc tumour 6 days after tumour cell engraftment. Fluorescence imaging and brain collection were performed 1 h after i.v. injection of 18 μg of ZEGFR:03115-IR700 (tumour diameter, 2.7 mm). Haematoxylin/eosin staining and EGFR immunostaining on the same mouse. B Quantification of intratumoural infiltration of CD4+ and CD8+ (gated on CD45+) T cells and their upregulation of CD69 early activation marker assessed by flow cytometry. Cells were isolated from brain tumour masses 24 h post-PIT treatment (18 μg ZEGFR:03115-IR700 + 50 J/cm2); n = 10 per group. Statistical difference between the PIT-treated and control cells was calculated using the Mann-Whitney t test. The results were considered significant when *p ≤ 0.05 and ****p ≤ 0.0001. C Mouse serum pro-inflammatory cytokine concentrations 24 h after PIT treatment (18 μg ZEGFR:03115-IR700 + 50 J/cm2). Statistical difference in comparison with the control group determined using ANOVA with Dunnett’s post hoc test. ****p ≤ 0.0001. D Normalised PD-L1 expression level on the surface of BL6-NPE-GFP-Luc cells (gated on GFP+) isolated from mouse brains 24 h post-PIT treatment (18 μg ZEGFR:03115-IR700 + 50 J/cm2) in comparison with the control groups (with or without 50 J/cm2 irradiation). Statistical difference in comparison with the control group determined using the Mann-Whitney t test. **p ≤ 0.01