Cellular behavior of human mesenchymal stem cells cultured on single-walled carbon nanotube film

The influences of carboxylic functionalized single-walled carbon nanotubes (SWCNTs) on cell adhesion, spreading and cell lineage commitment of human mesenchymal stem cells (hMSCs) were evaluated. hMSCs were cultured on a thin mesh like layer of SWCNTs with a vertical height of less than 100 nm. The influence of the SWCNT film was significant on the cell spreading and focal adhesion distribution. Cells spread better on a SWCNT film as compared to cover slip (control), resulting in larger cell area and have higher occurrence of filopodia (microspikes) at the cell boundaries. Cytoskeleton arrangement was observed to be less orientated in the cells cultured on a SWCNT film as compared to control. Neurogenic markers such as nestin, glial fibrillary acidic protein and microtubule associated protein 2 genes were transiently upregulated (a process where cellular components, in this case RNA, is increased in response to external variable) over the first week while genes indicative of osteogenesis remained at its nominal level. These results suggest that nano roughness alone is sufficient to modulate cellular behavior and early stage of stem cell lineage commitment without the aid of an induction medium.