Cell proliferation and osteogenic differentiation of equine mesenchymal stem cells on biodegradable biomimetic tubular bacterial cellulose composites

We have recently reported that native bacterial cellulose (BC) with randomly oriented nanofibers supports in vitro proliferation and osteogenic and chondrogenic differentiation of equine bone marrow-derived adult mesenchymal stem cells (EqMSCs). The objective of this study was to develop biodegradable calcium-deficient hydroxyapatite (CdHA) tubular bacterial cellulose (BC-TS) composites with oriented nanofibers to mimic the hydroxyapatite minerals and inherent oriented collagen fibers in native bone for in vivo application. The biocompatible gel-like BC-TS was synthesized using the bacterium Gluconacetobacter sucrofermentans under static culture in oxygen-permeable silicone tubes. The BC-TS scaffolds were modified using a periodate oxidation to yield biodegradable scaffolds. To mimic bone tissue, the BC-TSs were mineralized with CdHA. The morphological property of the resulting composites was characterized in addition to their ability to support and maintain EqMSCs growth, proliferation and osteogenic differentiation in vitro. The BC-TS exhibited oriented nanofibril structures with excellent mechanical properties. MTS assay demonstrated increasing proliferation and viability with time (days 1, 2 and 3). Cell-scaffold constructs were cultured for 8 days under osteogenic conditions and the resulting osteocytes were positive for alizarin red. In summary, biocompatible and biodegradable biomimetic BC-TS composites support the proliferation, viability and osteogenic differentiation of EqMSCs cultured onto its surface in vitro, allowing for future potential use for tissue engineering therapies.