Extracellular matrix imaging

Conjugates of proteins that bind extracellular matrix components and imaging agents are described for use in the in vivo imaging of the extracellular matrix. The conjugates may bind to major or minor protein components of the extracellular matrix, or to the carbohydrate component of matrix proteoglycans. In particular conjugates binding to elastin, collagen or to a glycosaminoglycan are envisaged. The conjugates according to the invention have some important advantages over existing tools for imaging extra cellular matrix components, in particular for applications in tissue-engineering expts. or MRI. The use of protein conjugates of the invention allow visualization of very small extra cellular matrix components, such as newly formed collagen fibrils. Use of conjugates of the Staphylococcus collagen-binding adhesin to image collagens in cell culture and in tissue samples is demonstrated. The adhesin did not bind tissue that did not contain collagen and were specific for the collagen bound by the adhesin.