Minimum criteria for defining induced mesenchymal stem cells

Abstract

Mesenchymal stem cells (MSCs) are a promising cell type for cell-based therapies.The therapeutic potential of MSCs has been verified in preclinical and clinical studies, however; low cell number in adult tissues, restricted expansion and differentiation capacity, and donor-related heterogeneity limit their use. To address these issues, there has been considerable interest in induced pluripotent stem cells (iPSCs) derived MSCs (induced mesenchymal stem cells [iMSCs]). Investigators obtain iMSCs from iPSCs of different origins, with variable methods of generation and expansion. Results of current studies have suggested iMSCs as a unique alternative source of MSCs. However, iMSCs are defined using the same criteria (proposed previously for primary MSCs by the International Society for Cellular Therapy [ISCT]) without realizing the distinct nature of iMSCs as compared to primary MSCs. To rationally define iMSCs, additional characterization is proposed along with ISCT's minimum criteria for defining primary MSCs. Minimum criteria for defining iMSCs should include (1) spindle-shaped morphology, (2) plastic adherent growth, (3) positive expression of CD29, CD44, CD73, CD90, CD105, along with negative expression of hematopoietic markers (CD45, CD34, CD14 or CD11b, CD79α or CD19, HLA-DR), (4) lack of expression of iPSCs induction factors, (5) trilineage differentiation potential, (6) lack of ability to form teratoma, and (7) release of MSC relevant paracrine factors. Defining the minimum criteria for iMSCs will be of great interest in the field and will provide a uniform description and identification of iMSCs to expedite progress in the field. Furthermore, due to increased interest in the clinical use of iMSCs, the above-mentioned additional characterization before the clinical application is important to avoid unwanted complications for recipients.

Strategies to Convert Cells into Hyaline Cartilage: Magic Spells for Adult Stem Cells

“…In addition, for the use of the term “stem” cells, it is important to confirm the self-renewal of cells in vivo or in vitro [ 71 ]. Finally, the presence of immunomodulatory properties and the characterization of trophic factors secreted by MSCs and some miRNAs have been recommended to become mandatory criteria [ 71 , 73 , 74 ].…”

Exosomes derived from BMSCs alleviates high glucose‐induced diabetic retinopathy via carrying miR‐483‐5p

“…Meanwhile, microscopy and detection of CD105, CD90, CD45, and CD34 were used for identifying the BMSCs as previously listed. [ 15 ]…”

Therapeutic Strategy of Mesenchymal-Stem-Cell-Derived Extracellular Vesicles as Regenerative Medicine

“…The minimum criteria for defining human MSCs are (1) adherence to plastics under standard culture conditions; (2) positive cell surface markers CD73, CD90, CD105, and negative CD11b or CD14, CD19 or CD79a, CD34, CD45, and HLA-DR; and (3) ability to differentiate into osteoblasts, chondrocytes, and adipocytes [ 166 ]. Since MSCs express major histocompatibility complex (MHC) class I, but not MHC class II, they are less likely to be attacked by natural killer (NK) cells and exhibit difficulty in developing humoral immunity.…”