Cell‐cycle phases and genetic profile of bone marrow‐derived mesenchymal stromal cells expanded in vitro from healthy donors

Abstract

Human mesenchymal stromal cells (MSCs) expanded in vitro for cell therapy approaches need to be carefully investigated for genetic stability, by employing both molecular and conventional karyotyping. Reliability of cytogenetic analysis may be hampered in some MSC samples by the difficulty of obtaining an adequate number of metaphases. In an attempt to overcome this problem, a methodology apt to evaluate the cell-cycle structure on synchronous MSCs was optimised. Results obtained in five independent experiments by comparing cell-cycle analysis of synchronous and asynchronous MSC populations evaluated at early and late culture passages documented that in synchronous MSCs, 30% of cells entered G2/M phase after about 27-28 h of culture, while in asynchronous MSCs only 8% of cells in G2/M phase could be observed at the same time point. Cytogenetic analysis on synchronous MSCs allowed us to obtain 20-25 valuable metaphases/slide, whereas only 0-4 metaphases/slide were detectable in asynchronous preparations.

Mesenchymal Stem/Stromal Cells: A New ''Cells as Drugs'' Paradigm. Efficacy and Critical Aspects in Cell Therapy

“…On the contrary, spontaneous malignant transformation appears to be a rather exceptional event for human MSCs [105, 106]. Indeed, Rubio and co-workers [107] and Rosland and co-workers [108] have documented spontaneous malignant transformation in human MSCs expanded in vitro , but the results reported by both groups have subsequently been withdrawn, since it was demonstrated that spontaneous transformation reflected cross-contamination with established human immortalized cell lines [109, 110].…”

Role of Mesenchymal Stem Cells in Bone Regenerative Medicine: What Is the Evidence?

“…So far, several different approaches have been utilized to deliver MSCs into the injured area of the bone (i.e., bone defects) [Bernardo et al, 2007;Sorrell et al, 2009;Lee et al, 2010;Achille et al, 2011]. The most common method for using MSCs is direct injection [Chabner et al, 2004].…”

Resistance to neoplastic transformation ofex-vivoexpanded human mesenchymal stromal cells after exposure to supramaximal physical and chemical stress

“…After initial reports on the occurrence of neoplastic transformation in ex-vivo expanded huMSCs after long-term culture [16, 17, 18] this event has been subsequently described as uncommon, with an estimated frequency of <10 −9 [19, 20, 21, 22]. Furthermore, neither ectopic tissue formation nor MSC-originating tumors have ever been reported so far in hundreds of patients treated with MSC therapy [23].…”