Objective: Meniscus progenitor cells (MPCs) have been identified as promising candidates for meniscus regeneration, and it is crucial for us to understand meniscus injury repair mechanism at the cellular level. In this study, we investigate the biological properties of MPCs isolated from different species using the differential adhesion to fibronectin (DAF) technique. We aim to characterize MPCs in different species and evaluate the feasibility of these models for future meniscal investigation. Design: MPCs were isolated from freshly digested meniscus from rat, rabbit, goat, and human cells using DAF. Biological properties, including proliferation, colony-forming, multilineage differentiation, and migration abilities, were compared in MPCs and their corresponding mixed meniscus cell (MCs) population in each species. Results: MPCs were successfully isolated by the DAF technique in all species. Rat MPCs appeared cobblestone-like, rabbit MPCs were more polygonal, goat MPCs had a spindle-shaped morphology, human MPCs appear more fibroblast-like. Compared with MCs, isolated MPCs showed progenitor cell characteristics, including multilineage differentiation ability and MSC (mesenchymal stem cells) markers (CD166, CD90, CD44, Stro-1) expression. They also highly expressed fibronectin receptors CD49e and CD49c. MPCs also showed greater proliferation capacity and retained colony-forming ability. Except for goat MPCs showed greater migration abilities than MCs, no significant differences were found in the migration ability between MPCs and MCs in other species. Conclusion: Our study shows that DAF is an effective method for isolating MPCs from rat, rabbit, goat, and human. MPCs in these species demonstrated similar characteristics, including greater proliferation ability and better chondrogenic potential.

The meniscus is an important cushioning structure of the knee joint, with the maintenance of its normal structure and function playing a crucial role in protecting the joint from early degeneration. Stem/progenitor cells could be the key to help researchers to have a deeper understanding of the biological process of meniscal injury repair and may be important in the meniscus tissue regeneration processes. To the best of our knowledge, there is currently a lack of comprehensive reviews on existing research about the meniscus progenitor cells (MPCs). By reviewing the existing MPC literature, we aim to provide insights for future research on meniscus regeneration. The isolation methods, biological characteristics and the translational application of MPCs were summarized. MPCs could be isolated according to their colony-forming ability, marker expression, migration ability, and differential adhesion to fibronectin. Most existing studies on surface markers of MPCs have largely followed the paradigm of mesenchymal stromal/stem cell research. Based on the information provided by their surface markers and expression profile, researchers located MPCs in the peripheral surface area of the meniscus. Few researches have investigated the translation and application of MPCs, with most studies being limited to MPCs extraction and subsequent reimplantation in vivo. MPCs are a group of meniscus-resident cells, which exhibit certain stem/progenitor cell characteristics, such as the ability to undergo multilineage differentiation in in vitro culture.