Synovial mesenchymal stem cells from osteo- or rheumatoid arthritis joints exhibit good potential for cartilage repair using a scaffold-free tissue engineering approach

Summary Objective To assess whether synovial mesenchymal stem cells (SMSCs) from patients with osteoarthritis (OA) or rheumatoid arthritis (RA) can be used as an alternative cell source for cartilage repair using allogenic tissue engineered construct (TEC). Methods 25 patients (17 female, average age 61.8 years) were divided according to their pathology (control trauma group; N =6, OA group; N = 6) and RA patients were subdivided into two groups to evaluate the impact of biologics in accordance with whether treated with biologics [Bio(+)RA; N = 7] or not [Bio(-)RA; N = 6]. We compared the following characteristics among these groups: 1) The cell proliferation capacity of SMSCs; 2) The influence of passage number on features of SMSCs; 3) The weight and volume of TEC from the same number of SMSCs; 4) Inflammatory cytokine gene expressions levels of TEC; 5) The chondrogenic potential of TEC; and 6) Osteochondral repair using TEC in athymic nude rats. Results SMSCs from the four groups exhibited equivalent features in the above evaluation items. In in vivo studies, the TEC-treated repair tissues for all groups exhibited significantly better outcomes than those for the untreated group and no significant differences among the four TEC groups. Conclusion SMSCs from OA or RA patients are no less appropriate for repairing cartilage than those from trauma patients and thus, may be an effective source for allogenic cell-based cartilage repair.