Force and scleraxis synergistically promote the commitment of human ES cells derived MSCs to tenocytes

Abstract

As tendon stem/progenitor cells were reported to be rare in tendon tissues, tendons as vulnerable targets of sports injury possess poor self-repair capability. Human ESCs (hESCs) represent a promising approach to tendon regeneration. But their teno-lineage differentiation strategy has yet to be defined. Here, we report that force combined with the tendon-specific transcription factor scleraxis synergistically promoted commitment of hESCs to tenocyte for functional tissue regeneration. Force and scleraxis can independently induce tendon differentiation. However, force alone concomitantly activated osteogenesis, while scleraxis alone was not sufficient to commit, but augment tendon differentiation. Scleraxis synergistically augmented the efficacy of force on teno-lineage differentiation and inhibited the osteo-lineage differentiation by antagonized BMP signaling cascade. The findings not only demonstrated a novel strategy of directing hESC differentiation to tenocyte for functional tendon regeneration, but also offered insights into understanding the network of force, scleraxis and bmp2 controlling tendon-lineage differentiation.

Three-Dimensional Culture and Transforming Growth Factor Beta3 Synergistically Promote Tenogenic Differentiation of Equine Embryo-Derived Stem Cells

“…The constructs formed by the ESCs after 7 and 14 days are strikingly similar to those formed by adult equine tenocytes, and highly resemble artificial tendon matrices from other species described in the literature. [12][13][14] It should be noted, however, that tenocyte-seeded constructs tended to have a higher proportion of cells throughout the body of the construct than those seeded with ESCs, which showed an almost exclusive cell localization to the periphery of the collagen matrix.…”

“…Three-dimensional constructs have also been utilized to manipulate and direct certain pathways of differentiation in stem cells, including those of tenocyte lineages from MSCs. These include growth under ''static tension'' (produced by anchoring the gel), 8,[12][13][14] ''uniaxial applied tension'' (an externally applied constant force), 15 ''cyclical tension'' (exposure to externally applied and released forces), 12,16 and seeding cells on electrochemically aligned collagen. 17 When cells are cultured in anchored gels, they are under tension in what has been described as a ''static'' culture system.…”

Tendon development and musculoskeletal assembly: emerging roles for the extracellular matrix

“…In vitro, Scx overexpression is sufficient to transform mesenchymal stem cells (MSCs) and human embryonic stem cells (hESCs) into tenocytes ( Fig. 2A) (Alberton et al, 2012;Chen et al, 2012;Li et al, 2015). Thus, considerable effort has been made to elucidate the functions of Scx in the tenocyte lineage and to identify its downstream targets.…”

Cyclic tensile strain enhances human mesenchymal stem cell Smad 2/3 activation and tenogenic differentiation in anisotropic collagen-glycosaminoglycan scaffolds

“…Matrix mechanical cues have shown to be important tools for altering stem cell differentiation profiles (Engler et al, 2004;Hao et al, 2013;Janmey and McCulloch, 2007). Of particular interest to tendon applications, mechanical force has been shown to be a critical element in the recruitment of scleraxis-expressing cells to the tendonbone-junction enthesis during development (Chen et al, 2012;Schweitzer et al, 2010), as well as in promoting rehabilitative healing of the enthesis after injury Thomopoulos et al, 2008). In addition to playing a role in development, mechanotransduction pathways, activated through microstructural cues and applied mechanical stimulation, can influence stem cell activation and differentiation.…”