Osteogenic differentiation of stem cells on mesoporous silica nanofibers

Abstract

Electrospun nanofibrous scaffolds have gained momentum in regenerative medicine research due to their ECM-like architecture. The present study reports the fabrication of mesoporous silica nanofibers (MSF) and explores their potential to trigger osteogenic differentiation of human bone marrow derived mesenchymal stem cells (BM-MSCs) in the presence and absence of biochemical (induction) factors. BM-MSCs were seeded on MSF and allowed to differentiate into osteogenic lineage. Osteogenic differentiation of BM-MSCs was confirmed by mineralization staining, reduction in the expression of the stem cell marker CD105 and increase in the osteogenic marker osteocalcin. Cells cultured in MSF in the presence of induction media exhibited better adhesion, proliferation and differentiation. The phenotypic markers of osteoblasts such as mineralization and alkaline phosphatase (ALP) activity were higher on MSF in the presence of induction media when compared to MSF in the presence of normal media (p < 0.05). Upregulation of osteoblast specific genes (osteonectin, osteocalcin & alkaline phosphatase) suggests the potential of MSF to support osteogenic differentiation even in the absence of induction media (p < 0.05). In vitro results indicate that the nanotopography of MSF provided a favorable milieu for adhesion and proliferation of BM-MSCs. Further, the combination of the biomimetic nature of MSF, dissolution of silica ions (chemical cues) and biochemical cues presents a stable microenvironment for the differentiation of BM-MSCs into osteogenic lineage. In conclusion, the synergy of adhesion and proliferation cues in MSF along with suitable biochemical cues could be a promising design strategy to develop scaffolds for orchestrated bone healing.