Superiority of synovial membrane mesenchymal stem cells in chondrogenesis, osteogenesis, myogenesis and tenogenesis in a rabbit model.

Engineering complex tissues is perhaps the most ambitious goal of all tissue engineers. Despite significant advances in tissue engineering, which have resulted in successful engineering of simple tissues such as skin and cartilage, there are a number of challenges that remain in engineering of complex, hybrid tissue structures, such as osteochondral tissue. Mesenchymal stem cells (MSCs) have the capacity to highly proliferate in an undifferentiated state and the potential to differentiate into a variety of different lineages, providing a promising single cell source to produce multiple cell types. MSC obtained from adult human contribute to the regeneration of mesenchymal tissues such as bone, cartilage, fat, muscle, tendon and marrow stroma. In the present study, the regeneration capacity of multipotent MSCs derived from different tissues in the rabbit were compared. Specifically the aim of this study was to isolate and characterize rabbit adult stem cell populations from bone marrow, adipose, synovial membrane, rotator cuff, ligament and tendon and assess their cell morphology, growth rate, cell surface markers and differentiation capacity. MSCs derived from synovial membrane showed superiority in terms of chondrogenesis, osteogenesis, myogenesis and tenogenesis, suggesting that synovial membrane-derived MSCs would be a good candidate for efforts to regenerate musculoskeletal tissues.

Immunophenotypic Profile of CD34+ Subpopulations and Their Role in the Diagnosis and Prognosis of Patients with De-Novo, Particularly Low-Grade Myelodysplastic Syndromes.

BACKGROUND: Myelodysplastic syndromes (MDS) are clonal hematopoietic stem cell disorders with unknown aetiology. Multiparameter flow cytometry (MFC) is being evaluated for the diagnosis and prognosis of MDS. METHODS: In the present study, five-color MFC was performed on bone marrow aspirates of 50 untreated patients, newly diagnosed with MDS and 27 age matched control samples. Patients were classified according to World Health Organization 2016, International Prognostic Scoring System (IPSS), and Revised IPSS (IPSS-R). RESULTS: Significantly higher CD133+/CD90-CD45weak, CD117+/TdT-CD45weak, and CD33+/MPO-neutrophil precursor percentages on CD34+ cells, as well as a significant decrease of lymphoid and erythroid precursors were observed in the group of MDS patients in comparison to controls. A new scoring system was based on these findings, which can be helpful in discriminating lower risk MDS patients, including those with normal karyotype (a subgroup of MDS with diagnostic challenges). In addition, an increased level of apoptosis of CD34+/CD117+ cells was identified as an independent favorable prognostic factor both for the risk of transformation to acute myeloid leukemia and for overall survival. CONCLUSIONS: A new scoring system based on the expression of immature cell antigens on CD34+ cells (by itself or in combination with the Ogata score) can discriminate lower risk MDS patients, including those with normal karyotype, from the normal control group. © 2018 International Clinical Cytometry Society.