Fig. 6

Histology: 323/A3-800CW is specifically located in head-and-neck a, b, breast c, and colon d tumors. Tumor tissue was sectioned 72 h after injection of 323/A3-800CW, MOPC21-800CW or IRDye 800CW. Shown are anti-GFP (brown, head-and-neck cancer, breast cancer) or cytokeratin (brown, colon cancer) immunohistochemistry stainings and overlays of NIR fluorescence (red) and anti-GFP/cytokeratin stainings. In all tissue a clear overlap is seen between NIR fluorescence from 323/A3-800CW and anti-GFP immunohistochemistry staining (indicating tumor). NIR fluorescence is mainly located in the border of tumors and even small tumor islands (*) are NIR fluorescent. A low, non specific fluorescence signal was observed in sections with MOPC21-800CW and IRDye 800CW (B). T = tumor; N = normal tissue; C = center tumor; B = tumor border. A and B 1× zoom; C and D 10× zoom