Myogenic differentiation potential of human tonsil-derived mesenchymal stem cells and their potential for use to promote skeletal muscle regeneration

Abstract

Stem cells are regarded as an important source of cells which may be used to promote the regeneration of skeletal muscle (SKM) which has been damaged due to defects in the organization of muscle tissue caused by congenital diseases, trauma or tumor removal. In particular, mesenchymal stem cells (MSCs), which require less invasive harvesting techniques, represent a valuable source of cells for stem cell therapy. In the present study, we demonstrated that human tonsil-derived MSCs (T-MSCs) may differentiate into myogenic cells in vitro and that the transplantation of myoblasts and myocytes generated from human T-MSCs mediates the recovery of muscle function in vivo. In order to induce myogenic differentiation, the T-MSC-derived spheres were cultured in Dulbecco's modified Eagle's medium/nutrient mixture F-12 (DMEM/F-12) supplemented with 1 ng/ml transforming growth factor-β, non-essential amino acids and insulin-transferrin-selenium for 4 days followed by culture in myogenic induction medium [low-glucose DMEM containing 2% fetal bovine serum (FBS) and 10 ng/ml insulin-like growth factor 1 (IGF1)] for 14 days. The T-MSCs sequentially differentiated into myoblasts and skeletal myocytes, as evidenced by the increased expression of skeletal myogenesis-related markers [including α-actinin, troponin I type 1 (TNNI1) and myogenin] and the formation of myotubes in vitro. The in situ transplantation of T-MSCs into mice with a partial myectomy of the right gastrocnemius muscle enhanced muscle function, as demonstrated by gait assessment (footprint analysis), and restored the shape of SKM without forming teratomas. Thus, T-MSCs may differentiate into myogenic cells and effectively regenerate SKM following injury. These results demonstrate the therapeutic potential of T-MSCs to promote SKM regeneration following injury.

Application of differentiated human tonsil–derived stem cells to trembler‐J mice

“…Established methods were used for isolating T‐MSCs from tonsillar tissues . These were obtained during routine tonsillectomies and were minced and digested in Dulbecco's modified Eagle medium (DMEM; Invitrogen, Carlsbad, California) containing 210 U/ml collagenase type I (Invitrogen) and 10 μg/ml DNase (Sigma‐Aldrich, St. Louis, Missouri).…”

“…Furthermore, MSCs show immunomodulatory ability both in vitro and in vivo . Tonsil‐derived MSCs (T‐MSCs) show typical features of MSCs, including the ability to differentiate into tissues of the 3 primary germ layers . They also exhibit similar characteristics to bone marrow–derived MSCs (BM‐MSCs) and adipose tissue–derived MSCs (ASCs) .…”

“…[8][9][10][11][12][13][14][15][16] Mesenchymal stem cells (MSCs) have been considered as a potential therapeutic option. MSCs have been found in in many tissues, including tonsils, 17 bone marrow, 18 adipose tissue, 19 amniotic fluid, 20 umbilical cord blood, 21 placenta, 22 and dental pulp. 23 Isolated MSCs from these tissues are capable of self-renewal and differentiation into tissues with unrelated origins.…”

“…[18][19][20]22 Tonsilderived MSCs (T-MSCs) show typical features of MSCs, including the ability to differentiate into tissues of the 3 primary germ layers. 17,[24][25][26][27] They also exhibit similar characteristics to bone marrowderived MSCs (BM-MSCs) and adipose tissuederived MSCs (ASCs). 28 Nevertheless, the effects of donor age, long-term culture (15 passages), and cryopreservation on T-MSCs showed that they were maintained in terms of morphology, cell surface markers, and differentiation potential.…”

Cell therapy to improve regeneration of skeletal muscle injuries

“…have reported the potential efficacy of adipose‐derived MSCs in repairing supraspinatus and subscapularis muscle tears and attenuating fibrosis in models of rotator cuff injury. In injury models of volumetric muscle loss, improved muscle function (contractility) and structure (myofiber formation, reduction of scar tissue, increased blood vessel density) have been observed using MSCs from adipose tissue, bone marrow, cranial neural crest, and tonsil . The consensus on the mode of action of MSCs is on their paracrine/endocrine properties, but it is unclear whether the secreted factors act directly on muscle cell populations or locally/systemically modulate the immune environment …”