Figure 2.

Evaluation of anti-PD-1 (aPD1) in patient-derived ex vivo models. (A) Patient-specific MMR status and other relevant information. (B) Schematic representation of the experimental workflow from blood draw and surgical resection to ex vivo co-culture of patient-derived microtumors and autologous PBMCs. (C) Illustration depicting the dynamic interaction between microtumors and immune cells within the 3D environment. (D) Typical tissue morphology (bright field) and immunofluorescence (IF) viability data using Calcein AM (live, green) and BOBO-3 Iodide (dead, red) after long-term ex vivo culture. (E) Detection of interferon-gamma (IFNγ) secretion from perfused media collected every 24 hours for 7 days in the 3D tumor-immune cells co-culture for MSI (left) and MSS (right) CRC cases. Statistical significance was shown for MOD1 only. There is no statistical significance for MOD2. Statistical analysis was performed using a two-way ANOVA followed by Tukey’s HSD post-hoc test for IFNγ level between the treatment groups at each time point. (technical replicates n=3 unless indicated otherwise, *p<0.05, **p<0.01, ***p<0.001). (F) TUNEL assay was employed to detect apoptotic cells, where the presence of CFSE+ immune infiltration correlates with regions of cell death. ROI: region of interest.