Investigating the behavior of adult rat bone-marrow stromal cells on polydimethylsiloxane (PDMS) replica with tissue topography

Abstract

Extracellular matrix and microstructure topography are found to modulate physical factors of the growth of stem cells and other cellular properties. Our previous work has shown the possibility of deriving myelinating Schwann cell-like cells (SCLCs) from bone marrow stromal cells (BMSCs) of adult rats when co-cultured in contact with dorsal root ganglion (DRG) neurons, suggesting the importance of physical contact and cues given by the cell-cell or cell-matrix interaction in guiding the cells to commit their fate towards Schwann cells. We hypothesize the surface topography of native tissue sections can provide physical cues for the BMSCs to differentiate towards the neuronal lineage and express neuronal markers. Polydimethylsiloxane (PDMS) was chosen to be the substrate to generate replicas with native section topography due to its transparency and ease for surface modification for shaping. PDMS replicas with high fidelity of tissue section topography of adult rat sciatic nerve and quadriceps, and bovine tendons are produced, and treated with oxygen plasma immersion to reduce hydrophobicity and increase biocompatibility for cell seeding. BMSCs seeded on the replicas expressed several neuronal markers such as GFAP, p75 and nestin, yet exhibiting a round shape morphology with a high nuclear to cytoplasm ratio. Our results suggested the possibility of guiding the differentiation of BMSCs using surface topography, while PDMS may not be a good substrate for the adherence of BMSCs unless its surface was otherwise modified.