Characterization and differentiation potential of bone marrowderivedmesenchymal stem cells of male albino rats

IntroductionMesenchymal stem cells (MSCs) are described as multipotent cells because of theirability to differentiate into a variety of different cells and tissue lineages.AimThe aim of this study was to characterize bone marrow-mesenchymal stem cells(BM-MSCs) from male albino rats and examine their ability to differentiate intoosteogenic and chondrogenic lineages.Materials and methodsBone marrow cells were cultured using complete medium. When the primary culturebecame nearly confluent, the adherent cells were prepared for Giemsa staining,immunostaining for CD44, CD29, and CD34, and transmission electron microscopyexamination. To examine the differentiation potential of BM-MSCs, two cell pelletswere prepared. One pellet was incubated in osteogenic-conditioned medium and theother pellet was incubated in chondrogenic-conditioned medium.ResultsNine days from primary culture, the adherent cells were seen as a dense homogenouspopulation of fibroblast-like cells. The immunostaining of MSCs revealed a positivereaction for CD44 and CD29 and a negative reaction for CD34. Ultrastructuralexamination revealed that the MSCs had many pseudopodia and eccentric andeuchromatic nuclei. Their cytoplasm was rich in free ribosomes, mitochondria,and rough endoplasmic reticulum. Examination of BM-MSCs in osteogenicconditionedmedium showed calcium deposition with Alizarin red staining, whereasin chondrogenic medium these cells showed positive immunoreaction for type IIcollagen and bluish cytoplasmic reaction for chondroitin sulfate with Alcian bluestaining.ConclusionMSCs were characterized by their morphology and CD44 and CD29 surfacemarkers. They also had the capacity to differentiate into osteogenic and chondrogeniclineages.