Nanostickers for cells: a model study using cell–nanoparticle hybrid aggregates

Abstract

We present direct evidence that nanoparticles (NPs) can stick together cells that are inherently non-adhesive. Using cadherin-depleted S180 murine cells lines, which exhibit very low cell-cell adhesion, we show that NPs can assemble dispersed single cells into large cohesive aggregates. The dynamics of aggregation, which is controlled by diffusion and collision, can be described as a second-order kinetic law characterized by a rate of collision that depends on the size, concentration, and surface chemistry of the NPs. We model the cell-cell adhesion induced by the "nanostickers" using a three-state dynamical model, where the NPs are free, adsorbed on the cell membrane or internalized by the cells. We define a "sticking efficiency parameter" to compare NPs and look for the most efficient type of NP. We find that 20 nm carboxylated polystyrene NPs are more efficient nanostickers than 20 nm silica NPs which were reported to induce fast wound healing and to glue soft tissues. Nanostickers, by increasing the cohesion of tissues and tumors, may have important applications for tissue engineering and cancer treatment.

Polymeric Nanoparticles Limit the Collective Migration of Cellular Aggregates

“…We reported previously that it is possible to entrap particles within cell aggregates by adding NPs to the cell suspension used in the preparation of aggregates by the hanging drop method. 14 This protocol was used here to prepare hybrid cells/particles over a wide range of particle concentration, from Φ = 10 –10 to 10 –3 volume fraction corresponding to F ≈ 10 –7 to 0.7. The overall range of NP volume fractions studied here is wider than in the case of the addition of particles to preformed aggregates, as measurements were not hampered by the opacity of the cell medium in highly concentrated suspensions.…”

How gluttonous cell aggregates clear substrates coated with microparticles

“…The formation of the aureole in the case of low MP concentration and its extension at long times in the case of all MP concentrations are analyzed by a model used successfully in our previous studies of the cell internalization of PsCarbo, PsAmine, and silica nanoparticles (NP) 6 . We demonstrated that as one increases the NP concentration in a suspension of cells, the NPs are internalized by the cells up to a concentration C is .…”

A Tour of My Soft Matter Garden: From Shining Globules and Soap Bubbles to Cell Aggregates

“…We show that nanoparticles (20 nm in size) can be used as a glue, nano stickers, to enable the formation of self-assembled aggregates by promoting cell-cell interactions (79) (Figure 14a). We find that carboxylated polystyrene nanoparticles are more efficient than the silica nanoparticles of the same size, which were reported by Leibler to induce fast wound healing and glue soft tissue.…”