Журнал тканевой науки и инженерии

The Effect of Aging and Culture Senescence on Fibroblast Proliferation and Osteogenic Differentiation

Abstract

Vera Grotheer, Daniel Eckhardt, Julia Schulz, Olga Messel, Joachim Windolf and Christoph V Suschek

Objective: The use of autologous cortical and cancellous bone remains the gold standard of bone-grafting. However, donor side morbidity, limited availability, and the risk of infections lead surgeons and researchers to seek suitable alternatives. Human fibroblasts are potent immunoregulatory cells with multipotent differentiation potential, which are easy to harvest and proliferate in vitro, which makes them attractive tools for bone tissue engineering. But for an autologous application in cell-based therapies, attention should be paid to the effect of donor age on differentiation potential. Culture senescence must also be considered, as some proliferation steps are necessary to obtain a sufficient cell number for therapeutic use.

Methods: The results of this study reveal that an additional supplementation of insulin-like growth factor 1 is more suitable for osteogenic differentiation of foreskin fibroblasts, evaluated with an alkaline phosphatase assay, and quantification of calcium deposition in the extracellular matrix.

Results: Our findings demonstrate that increasing donor age and culture senescence negatively affect the proliferation and osteogenic differentiation capacity of foreskin fibroblasts. These results suggest that the best approach to increase cell numbers is to optimize the seeding density, while additional growth factor application has no beneficial effect on the proliferation in early passages, analysed with a cell viability assay.

Furthermore, commonly used osteogenic differentiation strategies consist of an application of ascorbate- 2-phosphate, dexamethasone, and β-glycerophosphate. However, phenotypic and differentiation potential discrepancies exist between multipotent mesenchymal stromal cells from different tissue origins as well as among fibroblasts from different dermal origins.

Conclusion: This work illustrates, that human fibroblasts, provided by young donors and in early cell culture passages, are a viable cell source for bone tissue engineering.