Cellular recognition and trafficking of amorphous silica nanoparticles by macrophage scavenger receptor A.

The cellular uptake of engineered nanoparticles (ENPs) is known to involve active transport mechanisms, yet the biological molecules involved are poorly understood. We demonstrate that the uptake of amorphous silica ENPs by macrophage cells, and the secretion of proinflammatory cytokines, is strongly inhibited by silencing expression of scavenger receptor A (SR-A). Conversely, ENP uptake is augmented by introducing SR-A expression into human cells that are normally non-phagocytic.