Comparison of human olfactory and skeletal MSCs using osteogenic nanotopography to demonstrate bone-specific bioactivity of the surfaces.

Recently we identified a novel population of mesenchymal stem cells (MSCs) from human olfactory mucosa (OM-MSCs), a tissue which promotes neurogenesis throughout life, and demonstrated that they promoted CNS myelination to a greater extent than bone marrow-derived (BM)-MSCs. Previous data demonstrated that nanotopographies with a degree of disorder induce BM-MSC osteogenic differentiation. Thus, using biomaterials as non-chemical tools, we investigated if MSCs from a completely different cellular niche could be induced to differentiate similarly to nanoscale cues alone. Both MSCs differentiated into bone when cultured on nanotopographically embossed polycaprolactone (PCL) with a disordered pattern and heights but not on a "smooth" non-embossed PCL control substrate, but OM-MSC changes were at lower expression levels. Both MSCs showed similar increases in differentiation markers at the protein and mRNA level when plated on the two patterned surfaces. Thus, topographical cues from substrates with disordered patterns can up-regulate several MSC resident genes in both BM-MSCs and OM-MSCs. Moreover, antibody purified BM-MSCs had similar properties to non-purified BM-MSCs. These data suggest that MSCs from a neural cellular niche express similar bone-induced cues to BM-MSCs, suggesting that MSCs that inherently support nervous tissue can differentiate along the bone lineage in a similar manner to MSCs from a skeletal environment.