B. Double immunofluorescence staining of paired normal and carcinoma tissues from two CRC patients. The frozen tissue sections were incubated with mAb 7H7 at 1:50 dilution and anti-amyloid antibody A11 at 1:25 dilution, or mouse and rabbit IgG control, followed by incubation with Alexa Fluor 555-conjugated goat anti-mouse and Alexa Fluor 680-conjugated donkey anti-rabbit, both at 1:1000 dilution. Co-staining of FadA (red) and amyloid oligomers (green) was observed in the carcinoma but not normal tissues. The images were taken under 60X objective. Scale bar equals 10 μm. 