Background: Protein theranostics integrate both diagnostic and treatment functions on a
single disease-targeting protein. However, the preparation of these multimodal agents
remains a major challenge. Ideally, conventional recombinant proteins should be used as
starting materials for modification with the desired detection and therapeutic functionalities,
but simple chemical strategies that allow the introduction of two different modifications into a
protein in a site-specific manner are not currently available. We recently discovered two …