2 research outputs found
Computational Investigations of the Interaction between the Cell Membrane and Nanoparticles Coated with a Pulmonary Surfactant
When
inhaled nanoparticles (NPs) come into the deep lung, they develop
a biomolecular corona by interacting with the pulmonary surfactant.
The adsorption of the phospholipids and proteins gives a new biological
identity to the NPs, which may alter their subsequent interactions
with cells and other biological entities. Investigations of the interaction
between the cell membrane and NPs coated with such a biomolecular
corona are important in understanding the role of the biofluids on
cellular uptake and estimating the dosing capacity and the nanotoxicology
of NPs. In this paper, using dissipative particle dynamics, we investigate
how the physicochemical properties of the coating pulmonary surfactant
lipids and proteins affect the membrane response for inhaled NPs.
We pinpoint several key factors in the endocytosis of lipid NPs, including
the deformation of the coating lipids, coating lipid density, and
ligand–receptor binding strength. Further studies reveal that
the deformation of the coating lipids consumes energy but on the other
hand promotes the coating ligands to bind with receptors more tightly.
The coating lipid density controls the amount of the ligands as well
as the hydrophobicity of the lipid NPs, thus affecting the endocytosis
kinetics through the specific and nonspecific interactions. It is
also found that the hydrophobic surfactant proteins associated with
lipids can accelerate the endocytosis process of the NPs, but the
endocytosis efficiency mainly depends on the density of the coating
surfactant lipids. These findings can help understand how the pulmonary
surfactant alters the biocompatibility of the inhaled NPs and provide
some guidelines in designing an NP complex for efficient pulmonary
drug delivery
Unveiling the Molecular Structure of Pulmonary Surfactant Corona on Nanoparticles
The growing risk of human exposure
to airborne nanoparticles (NPs) causes a general concern on the biosafety
of nanotechnology. Inhaled NPs can deposit in the deep lung at which
they interact with the pulmonary surfactant (PS). Despite the increasing
study of nano-bio interactions, detailed molecular mechanisms by which
inhaled NPs interact with the natural PS system remain unclear. Using
coarse-grained molecular dynamics simulation, we studied the interaction
between NPs and the PS system in the alveolar fluid. It was found
that regardless of different physicochemical properties, upon contacting
the PS, both silver and polystyrene NPs are immediately coated with
a biomolecular corona that consists of both lipids and proteins. Structure
and molecular conformation of the PS corona depend on the hydrophobicity
of the pristine NPs. Quantitative analysis revealed that lipid composition
of the corona formed on different NPs is relatively conserved and
is similar to that of the bulk phase PS. However, relative abundance
of the surfactant-associated proteins, SP-A, SP-B, and SP-C, is notably
affected by the hydrophobicity of the NP. The PS corona provides the
NPs with a physicochemical barrier against the environment, equalizes
the hydrophobicity of the pristine NPs, and may enhance biorecognition
of the NPs. These modifications in physicochemical properties may
play a crucial role in affecting the biological identity of the NPs
and hence alter their subsequent interactions with cells and other
biological entities. Our results suggest that all studies of inhalation
nanotoxicology or NP-based pulmonary drug delivery should consider
the influence of the PS corona