Investigating Cell Surface Markers and Differentiation Potential of Compact Bone-Derived Mesenchymal Stem Cells

Background: The differentiation potential of mesenchymal stem cells (MSCs) derived from the bone-tissue to multiple lineages is not clear. Objective: This study was conducted to investigate the surface antigen expression and multilineage stem cell potential of the cells derived from culture of collagenase digested marrow-free compact bones of C57BL/6 mouse. Materials & Methods: Long bones of C57BL/6 mouse (n=6) were collected aseptically and bone marrow was flushed out. Collagenase-digested bone fragments were washed and cultured in plastic flasks. The plastic-adherent fibroblast-like spindle-shaped cells were cultured sequentially in multiple passages in low-glucose DMEM (Dulbecco’s Modified Eagle’s Medium) supplemented with 15% FBS (Foetal Bovine Serum) and antibiotics in a 37°C incubator with 5% CO2. Immunophenotyping for cell surface markers was done using flow cytometry. The cells were differentiated into the osteoblastic, adipogenic and chondrogenic lineages. Results: The culture of the adherent cells exhibited active proliferation and multiplication in consequent passages. The cultured cells revealed evidence of adipogenic and osteogenic differentiation confirmed by staining with oil red O and von Kossa stains. Under flow cytometry observation, a significant proportion of cultured cells expressed CD29 and stem cell antigen (Sca-1). Only 9.8% cells showed expression of CD105. These MSCs exhibited low ability in chondrogenic differentiation, which can potentially be attributed to their lack of CD105 expression. Lack of expression of CD45 showed evidence of absence of hematopoietic stem cells. Conclusion: This study showed that murine compact bone-chip culture can yield MSCs with significant proliferation capacity. The cells displayed the ability to differentiate into osteoblast and adipocyte lineages.