Bone marrow-derived from the human femoral shaft as a new source of mesenchymal stem/stromal cells: an alternative cell material for banking and clinical transplantation

BACKGROUND: Mesenchymal stem/stromal cells (MSC) are commonly used in regenerative medicine. Among different tissues, iliac crest bone marrow (BM) represents the most exploited source, but its disadvantages are a painful aspiration procedure and low cell number. An alternative, readily available source of MSC for research would be beneficial for regenerative medicine development. This work aimed to propose a new source of bone marrow isolation in which the femoral shaft is taken during total hip arthroplasty (THA). METHODS: In preliminary experiments, three different gradient methods for cell separation (Ficoll-Paque 1.078 g/mL, 17% sucrose gradient, BM seeding fraction) were tested with regard to the time of primary culture, initial cell number, the phenotype, and morphology of MSC. Then human bone marrow MSC derived from two different sources, iliac crest aspirate (BM-MSCi) or femoral shaft (BM-MSCt), were analyzed in terms of cell number and colony-forming ability followed by differentiation potential of MSC into osteo-, chondro-, and adipogenic lineages as well as mRNA expression of a variety of cytokines and growth factors. RESULTS: Our studies showed that MSC isolated from the bone marrow of two different sources and cultured under appropriate conditions had similar characteristics and comparable propensity to differentiate into mesodermal cells. MSC derived from BM-MSCi or BM-MSCt expressed various growth factors. Interestingly, the expression of EGF, FGF, IGF, and PDGF-A was much higher in BM-MSCt than BM-MSCi. CONCLUSIONS: The results of our study demonstrate that human MSC isolated from the BM of the femoral shaft have similar biological characteristics as MSC derived from the iliac crest, suggesting the femoral shaft as a possible alternative source for mesenchymal stem/stromal cells.