ANTIBODIES LABELED WITH FLUORESCENCE-AGENT EXCITABLE BY INFRARED RAYS

Endoscopy is not significantly better than fiberscopy for the diagnosi s of minute cancers of the digestive tract. However, labeling of these lesions with an agent that can be detected videoendoscopically, with subsequent computer processing of the electronic signals, should facil itate endoscopic diagnosis of microlesions. We developed an antibody l abeled with an indocyanine green(ICG) derivative that has a specific f luorescence emission at 807 nm upon excitation at 768 nm. The physioch emical characteristics of this labeled antibody resemble those of ICG. The activity of the antibody is suitable for immunohistochemical stai ning, and the antibody fluoresces under infrared ray excitation. This antibody should prove useful for performing vital immunostaining for i nfrared endoscopy.