Polyphenol‐Scaffolded Modular Assembly of Heterotypic Cell–Cell Assemblies for Potentiating Cancer Immunotherapy

Abstract Cells existing in the form of clusters often exhibit distinct biological functions from their single‐cell counterparts. However, the ability to modulate cell–cell interactions among multiple cell types through molecular scaffolds remains an ongoing challenge. Here, a supramolecular phenolic network on surfaces of live cells designed is engineered to act as modular scaffolds that promote intercellular interactions, presenting a universal platform for the construction of cell–cell assemblies (CCAs). Utilizing the inherent cell surface affinity of supramolecular phenolic network modules, a series of heterotypic CCAs is efficiently established by assembling five distinct microorganisms and five types of mammalian cells. A specific application of CCAs with the combination of L. casei and macrophages ( L. casei @Mφ) is highlighted for enhanced cancer immunotherapy. Upon intravenous administration, L. casei @Mφ allows the chemotactic Mφ to facilitate the accumulation of L. casei at the tumor. The accumulated L. casei enables the polarization of tumor‐associated Mφ toward a pro‐inflammatory phenotype, markedly improving the immunotherapeutic response, slowing tumor progression, and mitigating lung metastasis. This work demonstrates the potential of polyphenol‐scaffolded modular assembly in manipulating cell–cell interactions to enhance multicellular cooperation, offering a general approach to controlling complex cellular behaviors.