Development of a Functional Schwann cell Phenotype from Adult Porcine Bone Marrow

Abstract

Adult bone marrow cells (BMC) are a potential resource for use in regenerative medicine such as in the production of Schwann cells for the repair of damaged nerves. However, many reports of BMC‐derived Schwann cells have not shown a functional phenotype. The objective of this study was to induce BMC to differentiate into a cell type with both phenotypic and functional characteristics Schwann cells. Adult porcine bone marrow was collected, enriched by Histopaque density gradient centrifugation, and differentiated in Neurobasal media. After eight days in culture we found that BMC expressed the Schwann cell markers S‐100, O4, GFAP, and were positive for cholesterol using FluoroMyelin. These same cells had low p75 receptor expression but neuregulin (1–25nM) increased p75 levels by 24–48hrs. The BMC‐derived Schwann cells produced an ATP increase in intracellular Ca2+ [Ca2+]i, with agonist potency being UTP = ATP>ADP> AMP = adenosine. The agonists α,β,‐methylene‐ATP had little effect on [Ca2+]i while suramin blocked the ATP‐induced [Ca2+]i suggesting the presence of an ATP purinergic P2Y2 G‐protein coupled receptor. The staining for FluoroMyelin and the ATP‐induced [Ca2+]i changes were all attenuated in cells passaged >5 times in culture. Using an in situ culture assay we found that Quantum‐dot labeled BMC rapidly adhered and differentiated into Schwann cells on damaged nerves. Our studies indicate that adult BMC can be induced to form a functional Schwann cell phenotype that could provide a valuable source of cells for use in nerve regeneration studies.