Human Umbilical Cord–derived Mesenchymal Stem Cells into Oligodendrocyte-like Cells using Triiodothyronine as an Inducer: a Rapid and Efficient Protocol

Multiple sclerosis (MS) is a central nervous system (CNS)–specific autoimmune disease which is associated with severe destruction of myelin. One approach for rescuing MS patients is regenerating myelin-forming cells (Oligodendrocytes) by stem cell–based therapy. In the current work, human umbilical cord–derived mesenchymal stem cells (hUC-MSCs) were isolated from umbilical cords that were obtained postpartum. We used two steps of induction protocols to differentiate mesenchymal stem cells into oligodendrocyte-like cells: pre-induction stage and induction stage. For pre-induction stage, huc-MSCs were cultured in DMEM-F12 medium containing FBS 2% and 1 μM all-transretinoic acid for 2 days. For induction stage, firstly, the pre-induced cells were incubated in DMEM/F12 medium for 2 days in the presence of different growth factors such as; 5 ng/ml platelet-derived growth factor, 10 ng/ml basic fibroblast growth factor (bFGF). To this end, different triiodothyronine concentrations (T3): 0, 5, 12.5, 25, 50, 100, 200, and 400 ng/ml were added to the medium for 2 days. At the induction stage, the highest percentage of viability rate was found in low concentrations of T3 (5, 12.5 and 25 ng/ml). The immunofluorescence results indicated that expressions of Olig2 and O4 were just detected in cells treated by T3, and maximum protein expression was recorded in T25 ng/ml concentration. The maximum mRNA expression of nestin was detected in pre-induction stage; however, the expressions of Olig2 and PDGFR-α were significantly higher at the end of induction stage. Our work showed that hUC-MSCs can potentially differentiate into oligodendrocyte-like cells by using T3 as an inducer which can be used in the future as a promising therapeutic strategy in MS disease. Lay Summary The highest percentage of viability rate was found in low concentrations of T3 (5, 12.5, and 25 ng/ml). In addition, our immunofluorescence data indicated that expressions of Olig2 and O4 (oligodendrocyte markers) were just detected in cells treated with T3, and maximum protein expression was recorded in T25 ng/ml concentration. The maximum mRNA expression of nestin was detected in the pre-induction stage. However, the expressions of Olig2 and PDGFR-α were significantly higher at the end of the induction stage. Our work showed that hUC-MSCs could potentially differentiate into oligodendrocyte-like cells by using T3 as an inducer which can be used in the future as a promising therapeutic strategy in MS disease.