7. Dendritic Cell–Biomaterial Interactions: Implications for the Onset and Development of the Foreign Body Response

Biomaterials are used in several clinical applications. Yet they often induce a strong immune response that can lead to implant malfunction and replacement. Thus, it is of crucial importance to deeply understand the biological response to biomaterials. Here, we focus on the molecular mechanisms underlying biomaterial–dendritic cell (DC) interactions. Biomaterials regulate DC adhesion via podosomes in a β2 integrin-dependent manner. Moreover, they primarily affect DC phenotype and function by impinging on multiple Toll-like receptor signaling pathways. By putting biomaterial–DC interactions (and their consequences) in the context of the foreign body response (FBR), we propose that DCs, whose function has been altered by biomaterials, could be engaged in multiple juxtacrine and paracrine interactions with other immune cells including macrophages and neutrophils. Through this complex intercellular network, DCs could affect the immune response at the implantation site initiating (or sustaining) the series of events leading to the FBR. The detailed knowledge of biomaterial–DC interactions could be exploited to design more inert biopolymers, thus minimizing the FBR or biomaterials that elicit controlled and specific immune reactions.