Differential proteomics highlights macrophage-specific responses to amorphous silica nanoparticles

TL;DR

This study uses differential proteomics to reveal macrophage-specific responses to amorphous silica nanoparticles, showing effects on cytoskeleton, phagocytosis, immune response, and increased sensitivity to DNA damage agents.

Contribution

It provides new insights into the cellular mechanisms and specific vulnerabilities of macrophages exposed to silica nanoparticles, using combined proteomic and targeted approaches.

Findings

Alterations in cytoskeleton and phagocytosis in macrophages

Enhanced sensitivity to DNA alkylating agents

Selective macrophage responses to nanosilica

Abstract

The technological and economic benefits of engineered nanomaterials may be offset by their adverse effects on living organisms. One of the highly produced nanomaterials under such scrutiny is amorphous silica nanoparticles, which are known to have an appreciable, although reversible, inflammatory potential. This is due to their selective toxicity toward macrophages, and it is thus important to study the cellular responses of this cell type to silica nanoparticles to better understand the direct or indirect adverse effects of nanosilica. We have here studied the responses of the RAW264.7 murine macrophage cells and of the control MPC11 plasma cells to subtoxic concentrations of nanosilica, using a combination of pro-teomic and targeted approaches. This allowed us to document alterations in the cellular cytoskeleton, in the phagocytic capacity of the cells as well as their ability to respond to bacterial stimuli. More surprisingly, silica nanoparticles also induce a greater sensitivity of macrophages to DNA alkylating agents, such as styrene oxide, even at doses which do not induce any appreciable cell death.