Novel applications of nanobodies for in vivo bio-imaging of inflamed tissues in inflammatory diseases and cancer.

In vivo imaging technology holds promise for refined monitoring of inflammation, both in the clinic and in preclinical animal models, with applications including improved diagnosis, prognosis and therapy monitoring. In particular, molecular imaging, aimed at non-invasively studying molecular and cellular processes in intact organisms, can hereby not only provide information about the amount of inflammation, but also on the type of inflammation and on cells and/or receptors involved. Hereto, an important requisite is the availability of the proper biomarkers and specific probes for targeting these biomarkers. In the current review, we focus on a number of markers on inflamed endothelium and infiltrating myeloid cells (including macrophages) as interesting targets for tracking inflammatory reactions and argue that such markers are not only useful in case of inflammatory diseases of infectious or autoimmune origin, but also for monitoring cancer evolution through the associated inflammation. We elaborate on nanobodies as innovative, specific probes to target these inflammation-associated markers for in vivo molecular imaging.