Figure 1.

Interaction of nanomaterials and aggregates with DCs. Nanomaterials and aggregates can be internalized by several receptors present at immature DCs membrane, either by endocytic or phagocytic pathways. Protein aggregates will then be processed by DCs, leading to peptide presentation associated with MHC class II molecules to naive T-lymphocytes. Both nanomaterials coated with a corona or protein aggregates may also be seen as NAMPs and interact with PRR. This interaction can act as a danger signal that induces a signaling cascade leading to the transcription of maturation genes. Mature DC will then be able to express co-stimulation molecules and to produce cytokines and chemokines that will trigger naïve T-cells activation and polarization. These products can also increase ROS production and initiate the inflammasome activation. CR, complement receptor; DCs, dendritic cells; FcR, immunoglobulin constant fragment receptor; MHC, major histocompatibility complex; NAMP, nanoparticles-associated molecular patterns; PRR, pattern recognition receptors; ROS, reactive oxygen species; Scavenger R, scavenger receptor; TLR, toll-like receptor.