Cell surface engineering with polyelectrolyte-stabilized magnetic nanoparticles: A facile approach for fabrication of artificial multicellular tissue-mimicking clusters

Abstract

Regenerative medicine requires new ways to assemble and manipulate cells for fabrication of tissue-like constructs. Here we report a novel approach for cell surface engineering of human cells using polymer-stabilized magnetic nanoparticles (MNPs). Cationic polyelectrolyte-coated MNPs are directly deposited onto cellular membranes, producing a mesoporous semi-permeable layer and rendering cells magnetically responsive. Deposition of MNPs can be completed within minutes, under cell-friendly conditions (room temperature and physiologic media). Microscopy (TEM, SEM, AFM, and enhanced dark-field imaging) revealed the intercalation of nanoparticles into the cellular microvilli network. A detailed viability investigation was performed and suggested that MNPs do not inhibit membrane integrity, enzymatic activity, adhesion, proliferation, or cytoskeleton formation, and do not induce apoptosis in either cancer or primary cells. Finally, magnetically functionalized cells were employed to fabricate viable layered planar (two-cell layers) cell sheets and 3D multicellular spheroids.

The effect of magnetic stimulation on the osteogenic and chondrogenic differentiation of human stem cells derived from the adipose tissue (hASCs)

“…These particles were easily incorporated within hASCs, as supported by Prussian blue stain and by fluorescence and scanning electron microscopy analysis. Moreover, viability assays suggest that MNPs incorporated by hASCs do not jeopardize the integrity of cellular membranes and these results are supported by the literature [22,23]. Overall, hASCs maintained good viability levels in both basic and supplemented culture media throughout the experimental setup.…”

Stabilized Dye–Pigment Formulations with Platy and Tubular Nanoclays

“…To investigate the uptake/labeling and potential toxicity of quantum dots loaded halloysite, we have employed an in vitro toxicity model based on human primary and cancer cell cultures. We have used human skin fibroblasts and human prostate cancer cells . Figures and show that quantum dots loaded halloysite are clearly seen as bright dots inside the skin fibroblast cells.…”

Single‐Cell Nanometric Coating Towards Whole‐Cell‐Based Biodevices and Biosensors

“…Current cell immobilization techniques, such as chemical crosslinking, adsorption, microcontact imprinting or matrix embedment, suffer from the reduced viability of the immobilized cells, side effects by crosslinking, and irreversible immobilization . Coated cells with multi‐function can address these problems, such as using magnetic nanoparticles or LbL technique . Initially, polyelectrolytes coated yeast cells could attach to the patterned substrate, realizing the selective immobilization of the cells .…”