Mesenchymal stem cells (MSCs) are multipotent cells which can proliferate and replace dead cells in the body. MSCs also secrete immunomodulatory molecules, creating a regenerative microenvironment that has an excellent potential for tissue regeneration. MSCs can be easily isolated and grown in vitro for various applications. For the past two decades, MSCs have been used in research, and many assays and tests have been developed proving that MSCs are an excellent cell source for therapy. This review focusses on quality control parameters required for applications of MSCs including colony formation, surface markers, differentiation potentials, and telomere length. Further, the specific mechanisms of action of MSCs under various conditions such as trans-differentiation, cell fusion, mitochondrial transfer, and secretion of extracellular vesicles are discussed. This review aims to underline the applications and benefits of MSCs in regenerative medicine and tissue engineering.

Generation of induced pluripotent stem cells (iPSCs) and their differentiation into mesenchymal stem/stromal cells (iMSCs) have created exciting source of cells for autologous therapy. In this study, we have compared the therapeutic potential of iMSCs generated from urinary epithelial (UE) cells with the available umbilical cord MSCs (UC‐MSCs). For this, adult UE cells were treated with the mRNA of pluripotent genes (OCT4, NANOG, SOX2, KLF4, MYC and LIN28) and a cocktail of miRNAs under specific culture conditions for generating iPSCs. Our non‐viral and mRNA‐based treatment regimen demonstrated a high reprogramming efficiency to about 30% at passage 0. These UE‐iPSCs were successfully differentiated further into ectoderm, endoderm and mesoderm lineage of cells. Moreover, these UE‐iPSCs were subsequently differentiated into iMSCs and were compared with the UC‐MSCs. These iMSCs were capable of differentiating into osteocytes, chondrocytes and adipocytes. Our qRT‐PCR and Western blot data showed that the CD73, CD90 and CD105 gene transcripts and proteins were highly expressed in iMSCs and UC‐MSCs but not in other cells. The comparative qRT‐PCR data showed that the iMSCs maintained their MSC characteristics without any chromosomal abnormalities even at later passages (P15), during which the UC‐MSCs started losing their MSC characteristics. Importantly, the wound‐healing property demonstrated through migration assay was superior in iMSCs when compared to the UC‐MSCs. In this study, we have demonstrated an excellent non‐invasive and pain‐free method of obtaining iMSCs for regenerative therapy. These homogeneous autologous highly proliferative iMSCs may provide an alternative source of cells to UC‐MSCs for treating various diseases.

The process of bone repair has always been a natural mystery. Although bones do repair themselves, supplemental treatment is required for the initiation of the self-regeneration process. Predominantly, surgical procedures are employed for bone regeneration. Recently, cell-based therapy for bone regeneration has proven to be more effective than traditional methods, as it eliminates the immune risk and painful surgeries. In clinical trials, various stem cells, especially mesenchymal stem cells, have shown to be more efficient for the treatment of several bone-related diseases, such as non-union fracture, osteogenesis imperfecta, osteosarcoma, and osteoporosis. Furthermore, the stem cells grown in a suitable three-dimensional scaffold support were found to be more efficient for osteogenesis. It has been shown that the three-dimensional bioscaffolds support and simulate an in vivo environment, which helps in differentiation of stem cells into bone cells. Bone regeneration in patients with bone disorders can be improved through modification of stem cells with several osteogenic factors or using stem cells as carriers for osteogenic factors. In this review, we focused on the various types of stem cells and scaffolds that are being used for bone regeneration. In addition, the molecular mechanisms of various transcription factors, signaling pathways that support bone regeneration and the senescence of the stem cells, which limits bone regeneration, have been discussed.