Isolation and characterization of CD73+CD39+CD146+ mesenchymal stem cell subset from bone marrow.

BACKGROUND: Our mission is to cure hematopoietic malignancies through cell therapy. Time to transplant is a key challenge resulting in mortality of patients needing a transplant. Previous studies reported CD146+ mesenchymal stem cells (MSCs) regulating hematopoiesis in bone marrow (BM). In 2013, the study reported the existence in the synovium of a MSC subset, co-expressing CD73 and CD39, with greater osteo-chondrogenic potency and ability to produce adenosine. This subset expressed CD146, known to be associated with pericytes. AIM: To investigate the presence and characterization of the CD73+CD39+CD146+ MSC subset in BM. Furthermore, we explored the existence of this subset in mobilized blood. METHODS: BM cells were culture expanded up to passage 4. Flow cytometry was used to verify expression of CD73, CD39, and CD146 markers. Cell sorting was performed via BDFACS AriaTM Fusion. The subset was assessed for defined MSC characteristics and perivascular localization in BM sections. Peripheral blood derived MSCs were obtained through apheresis performed at Gift of Life under Institutional Review Board donor consent. RESULTS: Our findings demonstrated that the combination of CD73, CD39, and CD146 enabled the identification and purification of a subset of MSCs from culture-expanded BM, up to passage 4. This subset exhibited a CD45-CD73+CD39+CD146+ phenotype, along with self-renewal and multipotency abilities, and was located in perivascular areas of BM sections. Additionally, this subset was found in both single and dual-mobilized leukopaks. CONCLUSION: The CD73+CD39+CD146+ cell subset showed self-renewal and multipotency abilities and was located in perivascular areas of BM. Such cell subset was also reported in single and dual-mobilized leukopaks.