RESUMO
INTRODUCTION: Bone marrow (BM) represents the major source of mesenchymal stem cells (MSCs); however, umbilical cord blood (UCB) MSCs have some advantages over BM, such as a higher differentiation capability and noninvasive collection methods. OBJECTIVES: We compared antigen expression and cytokine-secretion by MSC from BM and UCB expanded with media supplemented with fetal bovine serum (FBS) or human platelet lysate (HPL). MATERIALS AND METHODS: We compared protocols for the expansion of hMSC starting from samples of BM or UCB by morphological analysis, calculation of population doubling numbers, and cytometry techniques using monoclonal antibodies (BD Biosciences). Using the last technique, cytokines were detected in brain homogenate supernatant fluids of MSC cultured in various media, using the Bio-Plex cytokine assay system (BD Biosciences). RESULTS: Calculating the number population doubling (PD) and colony-forming unit-(1)fibroblast (CFU-F) assays showed significantly better expansion with HPL compared with a selected batch of FBS and within fewer days: PD about 5 for 10%HPL versus 25 for fibroblast growth factor2 (FGF2) medium. By flow cytometry, we observed a greater number of BM MSCs compared with UCB MSCs, as well as differences in the expression of some MSC antigens, particularly CD105, CD90, and CD31. Analysis of cytokines: FGFb, RANTES, VEGF, IL-6, IL-8, G-CSF, and GM-CSF showed only some of them to be expressed: namely, IL-6, IL-8, and VEGF. MSCs derived from UCB showed low concentrations of these cytokines compared with MSCs derived from BM.
