Figure 5: Distribution of the MMAE released from ADCs in tumour tissues.
From: Imaging mass spectrometry for the precise design of antibody-drug conjugates

Original magnification, x10. The yellow rectangles on the bright field show the measurement area (1200 × 1200 μm). Pixel size, 10 μm; scale bar, 100 μm. The blue curved lines show the borders between the cancerous and stroma parts in the BxPC-3 tumour tissues. The MMAE images in the tumour tissues obtained from m/z 496.3 using MALDI-IMS are shown as pseudo-colour images (Red-Purple). The 5.0-mg/mL CHCA solution was applied with a pinpoint spray gun. Minimum intensity, 4; maximum intensity, 10. The merged images show the superposition of the IMS images on the measurement area image obtained 24 h after the administration of the ADCs. The red region of the merged images indicates the cancerous parts. (a) At 24 h after the administration of the human TF ADC, MMAE was distributed predominantly within the cancerous tissues. (b) The accumulation of MMAE within the cancerous parts was higher than that within the stroma parts in the BxPC-3 tumour tissues (Student’s t-test, **P = 0.003, N = 3 for each group). (c) Immunohistochemistry (mouse CD31 and IgG/ADC) revealed the distributions of the vascular endothelial cells and IgG on the corresponding ADCs, and H&E staining is shown in the left column.