Cell aggregation by scaffolded receptor clusters.

The aggregation of cells by lectins or antibodies is important for biotechnological and therapeutic applications. One strategy to augment the avidity and aggregating properties of these mediators is to maximize the number of their ligand binding sites. The valency of lectins and antibodies, however, is limited by their quaternary structures. To overcome this limitation, we explored the use of polymers generated by ring-opening metathesis polymerization (ROMP) as scaffolds to noncovalently assemble multiple copies of a lectin, the tetravalent protein concanavalin A (Con A). We demonstrate that complexes between Con A and multivalent scaffolds aggregate cells of a T cell leukemia line (Jurkat) more effectively than Con A alone. We anticipate that synthetic scaffolds will offer a new means of facilitating processes that rely on cell aggregation, such as pathogen clearance and immune recognition.