Specifically Formed Corona on Silica Nanoparticles Enhances Transforming Growth Factor β1 Activity in Triggering Lung Fibrosis

A corona is a layer
of macromolecules formed on a nanoparticle
surface in vivo. It can substantially change the
biological identity of nanomaterials and possibly trigger adverse
responses from the body tissues. Dissecting the role of the corona
in the development of a particular disease may provide profound insights
for understanding toxicity of nanomaterials in general. In our present
study, we explored the capability of different silica nanoparticles
(SiNPs) to induce silicosis in the mouse lung and analyzed the composition
of coronas formed on these particles. We found that SiNPs of certain
size and surface chemistry could specifically recruit transforming
growth factor β1 (TGF-β1) into their corona, which subsequently
induces the development of lung fibrosis. Once embedded into the corona
on SiNPs, TGF-β1 was remarkably more stable than in its free
form, and its fibrosis-triggering activity was significantly prolonged.
Our study meaningfully demonstrates that a specific corona component
on a certain nanoparticle could initiate a particular pathogenic process
in a clinically relevant disease model. Our findings may shed light
on the understanding of molecular mechanisms of human health risks
correlated with exposure to small-scale substances.