The Wnt5a Receptor, Receptor Tyrosine Kinase-Like Orphan Receptor 2, Is a Predictive Cell Surface Marker of Human Mesenchymal Stem Cells with an Enhanced Capacity for Chondrogenic Differentiation.

Sally C Dickinson,Kyla Brady,Ling Wu,Rhys L Williams,Suzanna Pang,Bruno Péault,Anna Salerno,Allen E Goodship,Theoni Katopodi,Christopher C West,Ashley W Blom,Roberta Ferro De Godoy,Catherine A Sutton,Wael Kafienah,Denis Evseenko,Anthony P Hollander

doi:10.1002/stem.2691

Abstract

Multipotent mesenchymal stem cells (MSCs) have enormous potential in tissue engineering and regenerative medicine. However, until now, their development for clinical use has been severely limited as they are a mixed population of cells with varying capacities for lineage differentiation and tissue formation. Here, we identify receptor tyrosine kinase‐like orphan receptor 2 (ROR2) as a cell surface marker expressed by those MSCs with an enhanced capacity for cartilage formation. We generated clonal human MSC populations with varying capacities for chondrogenesis. ROR2 was identified through screening for upregulated genes in the most chondrogenic clones. When isolated from uncloned populations, ROR2+ve MSCs were significantly more chondrogenic than either ROR2–ve or unfractionated MSCs. In a sheep cartilage‐repair model, they produced significantly more defect filling with no loss of cartilage quality compared with controls. ROR2+ve MSCs/perivascular cells were present in developing human cartilage, adult bone marrow, and adipose tissue. Their frequency in bone marrow was significantly lower in patients with osteoarthritis (OA) than in controls. However, after isolation of these cells and their initial expansion in vitro, there was greater ROR2 expression in the population derived from OA patients compared with controls. Furthermore, osteoarthritis‐derived MSCs were better able to form cartilage than MSCs from control patients in a tissue engineering assay. We conclude that MSCs expressing high levels of ROR2 provide a defined population capable of predictably enhanced cartilage production. Stem Cells 2017;35:2280–2291

Highlights

A method of identifying and isolating mesenchymal stem cells (MSCs) with an enhanced capacity for cartilage formation should provide a useful tool in regenerative medicine
We report the identification of inducible receptor tyrosine kinase-like orphan receptor 2 (ROR2), the Wnt5a receptor, as a cell surface marker that is predictive of significantly enhanced chondrogenesis by MSCs, allowing production of 35% more cartilage and 95% higher tissue quality when used to repair cartilage lesions in sheep
Each clone was cultured in expansion medium containing 2 ng/ml fibroblast growth factor-2 (FGF-2), which supports the proliferation of single-cell-derived populations [16] and maintains chondrogenic differentiation potential [17]

Summary

Introduction

A method of identifying and isolating mesenchymal stem cells (MSCs) with an enhanced capacity for cartilage formation should provide a useful tool in regenerative medicine. One study has used autologous MSC-generated chondrocytes to repair articular cartilage lesions in 40 patients with knee injuries [12]. Scale-up of these procedures for the routine production of implantable cartilage of consistently high quality remains a significant challenge, in part because of the lack of standardized methods for isolation of a functional cell population optimized for chondrogenesis. We report the identification of inducible receptor tyrosine kinase-like orphan receptor 2 (ROR2), the Wnt5a receptor, as a cell surface marker that is predictive of significantly enhanced chondrogenesis by MSCs, allowing production of 35% more cartilage and 95% higher tissue quality when used to repair cartilage lesions in sheep

Objectives

Methods

Results

Conclusion