Article

Silver nanoparticles do not influence stem cell differentiation but cause minimal toxicity

Center for Chemical Toxicology Research & Pharmacokinetics, North Carolina State University, NC, USA.
Nanomedicine (Impact Factor: 5.82). 05/2012; 7(8):1197-209. DOI: 10.2217/nnm.12.18
Source: PubMed

ABSTRACT To evaluate the toxicity and cellular uptake of both undifferentiated and differentiated human adipose-derived stem cells (hASCs) exposed to silver nanoparticles (Ag-NPs), and to assess their effect on hASC differentiation.
hASC were exposed to 10- or 20-nm Ag-NPs at concentrations of 0.1, 1.0, 10.0, 50.0 and 100.0 µg/ml either before or after differentiation down the adipogenic or osteogenic pathways.
Exposure of hASC to either 10- or 20-nm Ag-NPs resulted in no significant cytotoxicity to hASC, and minimal dose-dependent toxicity to adipogenic and osteogenic cells at 10 µg/ml. Each of the hASC, adipogenic and osteogenic cells showed cellular uptake of both 10- and 20-nm Ag-NPs, without causing significant ultrastructural alterations. Exposure to 10- or 20-nm Ag-NPs did not influence the differentiation of the cells, and at antimicrobial concentrations of Ag-NPs resulted in a minimal decrease in viability.
The biocompatibility of Ag-NPs with both undifferentiated and differentiated hASC establishes their suitability for incorporation into tissue-engineered graft scaffolds, for the prevention of bacterial contamination upon implantation.

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Available from: Nancy A Monteiro-Riviere, Aug 30, 2015
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