Comparison of phenotype, chondrogenic and osteogenic potential of rheumatoid mesenchymal stem cells derived from articular and subcutaneous adipose tissue - The role of adipocytokines

Abstract

A study was carried out to compare the phenotype, chondrogenic and osteogenic potential of adipose mesenchymal stem cells (ASCs) derived from articular adipose tissue (AAT) and subcutaneous adipose tissue (ScAT) of rheumatoid arthritis (RA) patients. We also aimed to evaluate the role of leptin (LEP), low molecular weight adiponectin isoform (LMW), high molecular weight adiponectin isoform (HMW) and tumor necrosis factor (TNF) in ASCs differentiation. AAT and ScAT were obtained from RA patients undergoing total knee joint replacement surgery. ASCs were isolated and expanded in vitro. Cells phenotype was assesed by flow cytometry; leptin and adiponectin receptors mRNA expression by RT-PCR. Differentiation was performed in chondrogenic and osteogenic medium with or without LEP, LMW, HMW and TNF. After differentiation, expression of mRNA for Sox9, aggrecan (Agr), collagen 2a (Col2a) for chondrogenesis, and BMP-2, Runx-2 and osteopontin (OPN) for osteogenesis was evaluated by RT-PCR. Dickkopf-1 (DKK-1) and osteoprotegerin (OPG) proteins concentrations were measured in supernatants from osteogenic cultures using ELISA. AAT and ScAT-ASCs have the same CD105+CD90+CD73+CD45-CD34+/-CD19-CD14- phenotype. AAT-ASCs seem to be more susceptible to chondrogenesis and osteogenesis in vitro. Adipocytokines do not exert strong effect on ASCs differentiation, however HMW slightly increased expression of chondrogenesis markers mRNA in AAT-ASCs. TNF diminished expression of all chondrogenesis markers and OPN, but enhanced expression of BMP-2 and Runx-2 mRNA.