Dual effects of fibrinogen decoration on the tuning of silica nanoparticles-induced autophagic response: The implication of sedimentation and internalization

Highlights: • Fibrinogen decoration ameliorate SiO₂ NPs-induced autophagy in non-phagocytic cells. • This effect of fibrinogen was compromised in phagocytic cells. • Fibrinogen decoration blocks SiO₂ NPs sedimentation. • Fibrinogen coverage inhibits SiO₂ NPs' cellular internalization. Due to the blooming development of nanotechnology, the further understanding of nanomaterials-induced toxicity has been demanded. Following their introduction into a biological matrix, the surface of nanoparticles (NPs) is covered by protein layer, namely corona, which imparts a new biological identity to NPs. Here, we showed that fibrinogen (Fg), but not albumin (BSA) or hemoglobin (Hb), decoration on the surface of silica nanoparticles (SiO₂ NPs) ameliorate their pro-autophagic activity in non-phagocytic cells. Surprisingly, this effect of Fg was compromised in phagocytic cells. Further mechanistic investigation suggested coronal Fg has dual effects on the tuning of SiO₂ NPs-induced autophagic response. First, Fg decoration blocks SiO₂ NPs sedimentation through stabilize SiO₂ NPs suspension; secondly, Fg coverage inhibits SiO₂ NPs' cellular internalization. These findings provided important insights into the understanding of NPs-corona complexes behaviors and indicate future directions for the investigation of corona-mediated biological activities.