The Effects of Mesenchymal Stem Cells on the Gene Expression of TGF-beta and IFN-gamma in Patients with Rheumatoid Arthritis

The therapeutic and immunomodulatory potential of mesenchymal stem cells (MSCs) in rheumatoid arthritis (RA) has attracted considerable scientific attention in recent decades. This study aimed to evaluate the expression of genes encoding interleukin (IL)4 and IL10, as well as interferon-gamma (IFNG) and transforming growth factor beta (TGFB1) in refractory RA patients following intravenous injection of autologous bone marrow-derived MSCs (BM-MSCs).
This study was registered in Iranian Registry of Clinical Trials (IRCT) (2015102824760N1) and ClinicalTrials.gov (identifier: NCT03333681). Blood samples were taken from 13 patients before and 1 and 6 months after the MSC injection to evaluate the clinical manifestations, paraclinical factors, and expression of IL4, IL10, IFNG, and TGFB1 genes employing the SYBR Green real-time reverse-transcriptase polymerase chain reaction (RT-PCR) technique.
There was a significant increase in the expression of TGFB1 at 1 and 6 months after the MSC injection compared to that in the baseline, while the expression of IL4 and IL10 did not change significantly. On the other hand, the expression of IFNG increased significantly after 1 month but decreased significantly at 6 months compared to 1 month after the intervention. Nevertheless, it showed no significant decrease compared to the baseline.
A significant decrease was observed for the expression of IFNG 6 months after the injection compared to that after 1 month, which was in concordance with the rise in the expression of the TGFB1 gene. A significant change in the gene expression of TGFB1 and IFNG in our study was consistent with the amelioration of clinical manifestations, suggesting a mechanism of action for MSCs in the treatment of RA.