Repair of Full-Thickness Tendon Injury Using Connective Tissue Progenitors Efficiently Derived from Human Embryonic Stem Cells and Fetal Tissues

Abstract

The use of stem cells for tissue engineering (TE) encourages scientists to design new platforms in the field of regenerative and reconstructive medicine. Human embryonic stem cells (hESC) have been proposed to be an important cell source for cell-based TE applications as well as an exciting tool for investigating the fundamentals of human development. Here, we describe the efficient derivation of connective tissue progenitors (CTPs) from hESC lines and fetal tissues. The CTPs were significantly expanded and induced to generate tendon tissues in vitro, with ultrastructural characteristics and biomechanical properties typical of mature tendons. We describe a simple method for engineering tendon grafts that can successfully repair injured Achilles tendons and restore the ankle joint extension movement in mice. We also show the CTP's ability to differentiate into bone, cartilage, and fat both in vitro and in vivo. This study offers evidence for the possibility of using stem cell-derived engineered grafts to replace missing tissues, and sets a basic platform for future cell-based TE applications in the fields of orthopedics and reconstructive surgery.

Biologic approaches to enhance rotator cuff healing after injury

“…A few studies have shown that MSCs and connective tissue progenitor cells can be isolated from human embryonic stem cells (hESCs). 6,9 For example, hESC-derived MSCs improve biomechanics and histologic appearance when used adjunctively to repair a rat Achilles tendon defect. 6 Alternatively, tendon grafts can be generated from connective tissue progenitor cells in culture and restore ankle joint extension when implanted in a mouse to bridge an Achilles tendon defect.…”

“…Interestingly, these tendon grafts appear to remodel in vivo over time, showing increased strength and vascular in-growth. 9 Adipose-derived stem cells and synovial MSCs have also shown efficacy in animal models of tendon repair. 26,58 In addition to stem cells, tenocyte-like fibroblasts, readily cultured from a human skin biopsy specimen, have been shown to be safe for patient injection.…”

Engineering Cellular Fibers for Musculoskeletal Soft Tissues Using Directed Self-Assembly

“…Current scaffold-free and cell-based engineering methodologies have produced tendon and ligament-like structures from two-dimensional (2D) cell monolayers cultured in dishes. Human connective tissue progenitor cells, 3 tendon fibroblasts, [4][5][6] and bone marrow stromal cells, 7 have been grown in monolayer culture and allowed to contract, or roll-up, to form three-dimensional (3D), fiber-like structures. Using an alternative scaffold-free approach, de Wreede and Ralphs 8 cultured a suspension of tendon fibroblasts in a rotating dialysis tube for 14 days to produce fiber-like cell aggregates.…”

Osteogenic Differentiation of Stem Cells Alters Vitamin D Receptor Expression

“…They also have the unique ability to differentiate into cell types comprising all 3 germ lineages, including cardiomyocytes, chondrocytes, osteoblasts, adipocytes, endothelial cells, or neurons [3][4][5]. In addition to their use in tissue engineering and regenerative therapies [6][7][8][9], ESCs have been used as an in vitro model to study early stages of cellular differentiation. ESCs spontaneously form 3-dimensional cell aggregates in suspension culture conditions and differentiate in the form of ''embryoid bodies'' (EBs) [10][11][12][13].…”