Equivalent osteoblastic differentiation function of human mesenchymal stem cells from rheumatoid arthritis in comparison with osteoarthritis

Abstract

Objective. To evaluate the osteoblastic differentiation of human mesenchymal stem cells (hMSCs) in patients with RA. Methods. Heparinized bone marrow aspirate was obtained from patients with OA and RA. Mononuclear cells were cultured for 2 weeks and a colony-forming assay was performed. The phenotype of cells was analysed by flow cytometry. Passage 2 cells were cultured with β-glycerophosphate (bGP) in the control group and bGP, ascorbic acid and dexamethasone in the differentiation group. After 2 weeks, ALP staining and activity were performed. After 3 weeks, Alizarin Red S assay was performed. Total RNA was extracted from cells cultured for 2 and 3 weeks. Gene expression of bone formation factor was examined by real-time PCR. Results. The phenotype of cells was identical in both OA and RA and the content was thought to be hMSCs. The results of ALP activity and Alizarin Red S assay showed higher levels in the differentiation group for both OA and RA samples compared with the control group. The results of a colony-forming assay were identical in both OA and RA samples. Gene expression in the differentiation group was higher than in the control group in both OA and RA samples. There was no significant difference between OA and RA samples in all experiments. Conclusion. The function of osteoblastic differentiation of hMSCs is similar between OA and RA. © The Author 2009. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved.