In vitro comparison of different carrier materials with rat bone marrow MSCs

Objectives: Injectable or implantable scaffolds seeded with autologous chondrogenic cells may represent a promising option for treatment of cartilage defects in the future. Current problems with the autologous chondrocyte implantation including dedifferentiation and the development of fibrocartilage suggest the use of alternative chondrogenic cell sources such as mesenchymal stromal cells (MSCs). The aim of this study was to compare the early effects of different scaffolds on the proliferation and metabolic activity of chondrogenic MSCs in vitro. Materials and methods: Multipotent stromal cells were isolated from rat bone marrow, phenotyped by flow cytometry, and differentiated into distinct lineages proved by lineage-specific staining and gene expression (RT-PCR) pattern. Cell proliferation on Tutodent® Membrane, Bio-Gide®, TissuFleece E, and Belotero® Soft was quantified by the MTT and WST-1 assay and direct determination of total cell numbers. Potential cytotoxic effects of eluates obtained from the materials were quantified by lactate dehydrogenase (LDH) and 5-bromo-2-deoxyuridine (BrdU) assay. Results: TissuFleece E displayed the best results regarding cell proliferation on the biomaterials and metabolic activity (MTT, WST-1) (p < 0.001). Yet, the eluates of TissuFleece E caused an increased LDH release and lower values in the BrdU test. Cell proliferations on Bio-Gide®, Tutodent® Membrane, and Belotero® Soft were similar to the control. The eluates of Belotero® Soft exhibited the highest LDH release and lowest values in the BrdU assay (p < 0.05). Conclusions: Our results support the use of Tissufleece E as scaffold for chondrogenic rat MSCs. However, it should be prewashed with culture medium before seeding of the cells. Clinical relevance: Tissufleece E may serve as a promising carrier material for chondrogenic MSCs for cartilage tissue engineering attempts.