introduction: The first non-hematopoietic mesenchymal stem cells (MSCs) were discovered by Friedenstein and he described clonal, plastic adherent cells from bone marrow capable of differentiation. MSCs have been studied in regenerative medicine because of their unique immunologic characteristics.MSCsare multipotent cells which can give rise to mesenchymal and non-mesenchymal tissues in vitro and in vivo.
Materials and MethodsRat bone marrow mesenchymal stem cellswere isolated from bone marrow aspirates of 10-20ml taken from the iliac crest of male rats. and cultured at 37 8C in humid air with 5% CO in DMEM containing 20% fetal bovine serum (FBS) (Gibco), penicillin (100 U/ml), streptomycin (100 mg/ml). The medium was changed to remove the nonadherent cells at 24 h after seeding, and every 3 days thereafter.then the primary and the first passaged MSCs were exposed to different concentrations (3, 5 and 10 mM) of 5-azacytidine for 24 h on day 3 of culture. The experiment was repeated in three 24-well plates with 12 wells for each treatment.
Results: The dynamic changes in morphology and the growth properties were compared with the untreated cultures at indicated time points.
Conclusion: Rat MSCs (rMSCs) sharing the same morphological and functional characteristics as human MSCs can besuccessfully isolated from adult bone marrow without previous rat or bone marrow treatment. Therefore, rMSCs will be an importanttool to study the in vivo behaviour and fate of this cell type after grafting in rat pathology models