Infrared photodetection for the in vivo localisation of phage-derived antibodies directed against angiogenic markers.

Angiogenesis, the formation of new blood vessels from pre-existing ones, is a characteristic process which underlies many diseases, including cancer, rheumatoid arthritis and blinding ocular disorders. Antibodies capable of selective targeting and occlusion of neovasculature would open diagnostic and therapeutic opportunities. We have recently demonstrated that phage-derived human antibody fragments with high affinity for the extra-domain B (ED-B) of fibronectin, a marker of angiogenesis, selectively localise in new-forming blood vessels upon intravenous injection. Here, we show that infrared fluorescence methodologies nicely complement radioactive techniques for the study of the antibody-mediated targeting of angiogenesis in a variety of animal models. Methods are presented for the construction and use of infrared fluorescence imagers, as well as for the production and characterisation of recombinant antibodies labeled with infrared fluorophores.