Induced pluripotent stem cell-derived tenocyte-like cells promote the regeneration of injured tendons in mice

Shingo Komura,Yasuhiro Yamada,Haruhiko Akiyama,Akihiro Hirakawa,Atsushi Goto,Kenji Ito,Hitomi Aoki,Hirofumi Shibata,Takashi Satake

doi:10.1038/s41598-020-61063-6

Abstract

Tendons are dense fibrous structures that attach muscles to bones. Healing of tendon injuries is a clinical challenge owing to poor regenerative potential and scarring. Here, we created reporter mice that express EGFP, driven by the promoter of the tendon-specific Scleraxis (Scx) transcription-factor gene; we then generated induced pluripotent stem cells (iPSCs) from these mice. Utilising these fluorescently labelled iPSCs, we developed a tenogenic differentiation protocol. The iPSC-derived EGFP-positive cells exhibited elevated expression of tendon-specific genes, including Scx, Mohawk, Tenomodulin, and Fibromodulin, indicating that they have tenocyte-like properties. Finally, we demonstrated that these cells promoted tendon regeneration in mice after transplantation into injured tendons reducing scar formation via paracrine effect. Our data demonstrate that the tenogenic differentiation protocol successfully provided functional cells from iPSCs. We propose that pluripotent stem cell-based therapy using this protocol will provide an effective therapeutic approach for tendon injuries.

Highlights

Tendons are dense fibrous structures that attach muscles to bones
There have been reports of several tenogenic differentiation protocols from pluripotent stem cells using transforming growth factor (TGF)-β3 and three-dimensional culture[15,16], bone morphogenic protein (BMP) 12/13 and ascorbic acid[17], and well-aligned, chitosan-based ultrafine fibers[18], none have described the isolation of tenogenic cells with measurements of induction efficiency
To produce homozygous Scx-EGFP mice, we intercrossed heterozygous mice; we obtained no homozygotes. The reason for this may be the Scx gene is located in the intronic region of the block of proliferation 1 (Bop1) gene, which is involved in ribosome biogenesis and chromosomal segregation[26]

Summary

Introduction

Tendons are dense fibrous structures that attach muscles to bones. Healing of tendon injuries is a clinical challenge owing to poor regenerative potential and scarring. We created reporter mice that express EGFP, driven by the promoter of the tendon-specific Scleraxis (Scx) transcription-factor gene; we generated induced pluripotent stem cells (iPSCs) from these mice Utilising these fluorescently labelled iPSCs, we developed a tenogenic differentiation protocol. Scx-GFP transgenic mice have been created[21,22] and used to investigate mechanisms of tendon development and the biological responses of tenocytes to cytokines and mechanical stress[6,23,24,25] We reasoned that this tendon-specific reporter system could be of great value in the development of a tenogenic differentiation protocol from pluripotent stem cells, which could be exploited for cell-based therapy for tendon injuries. Upon transplantation of the differentiated cells into injured tendons, they promoted tendon regeneration in mice

Methods

Results

Conclusion