Trogocytosis in innate immunity to cancer is an intimate relationship with unexpected outcomes.

ABSTRACT

Trogocytosis is a cellular process whereby a cell acquires a membrane fragment from a donor cell in a contact-dependent manner allowing for the transfer of surface proteins with functional integrity. It is involved in various biological processes, including cell-cell communication, immune regulation, and response to pathogens and cancer cells, with poorly defined molecular mechanisms. With the exception of eosinophils, trogocytosis has been reported in most immune cells and plays diverse roles in the modulation of anti-tumor immune responses. Here, we report that eosinophils acquire membrane fragments from tumor cells early after contact through the CD11b/CD18 integrin complex. We discuss the impact of trogocytosis in innate immune cells on cancer progression in the context of the evidence that eosinophils can engage in trogocytosis with tumor cells. We also discuss shared and cell-specific mechanisms underlying this process based on in silico modeling and provide a hypothetical molecular model for the stabilization of the immunological synapse operating in granulocytes and possibly other innate immune cells that enables trogocytosis.