IFN-γ-Primed hUCMSCs Significantly Reduced Inflammation via the Foxp3/ROR-γt/STAT3 Signaling Pathway in an Animal Model of Multiple Sclerosis

Abstract

Our previous study showed that interferon gamma (IFN-γ) might enhance the immunosuppressive properties of mesenchymal stem cells (MSCs) by upregulating the expression of indoleamine 2,3-dioxygenease. Therefore, we treated experimental autoimmune encephalomyelitis (EAE) mice, an animal model of multiple sclerosis (MS), with IFN-γ-primed human umbilical cord MSCs (IFN-γ-hUCMSCs). This study aimed to investigate the potential therapeutic effects of IFN-γ-hUCMSCs transplantation and to identify the biological pathways involved in EAE mice. Firstly, the body weights and clinical scores of EAE mice were recorded before and after treatment. Then, the inflammatory cytokine levels in splenic cell supernatants were quantified by enzyme-linked immunosorbent assay. Finally, the mRNA expression levels of signal transducer and activator of transduction 3 (STAT3), retinoic acid-related orphan receptor gamma t (ROR-γt), and forkhead box P3 (Foxp3) were detected by quantitative reverse transcription polymerase chain reaction. We observed that IFN-γ-hUCMSCs transplantation significantly alleviated body weight loss and decreased the clinical scores of mice. Additionally, IFN-γ-hUCMSCs transplantation could regulate the production of inflammatory cytokines, interleukin (IL)-10 and IL-17, thereby showing more potent treatment efficacy than human umbilical cord MSCs (hUCMSCs) transplantation (p < 0.05). Compared with the EAE group, the expressions of STAT3 and ROR-γt in the transplantation groups were significantly decreased, but the expression of Foxp3 was significantly upregulated in the IFN-γ-hUCMSCs transplantation group compared to that in the hUCMSCs transplantation group. We assumed that IFN-γ-hUCMSCs may affect the balance of T helper 17 (Th17) cells/regulatory T cells (Tregs) through the Foxp3/ROR-γt/STAT3 signaling pathway to reduce the inflammatory response, thereby improving the clinical symptoms of EAE mice. Our study demonstrated that transplantation of IFN-γ-hUCMSCs could reduce inflammation in EAE mice via the Foxp3/ROR-γt/STAT3 signaling pathway, highlighting the therapeutic effects of IFN-γ-hUCMSCs in patients with MS.

Interferon-γ-Treated Mesenchymal Stem Cells Modulate the T Cell-Related Chemokines and Chemokine Receptors in an Animal Model of Experimental Autoimmune Encephalomyelitis

“…The body weight was considerably higher and the clinical score reached zero on the last five days of the study in mice treated with IFN-γ-licensed MSC. In accordance with our data, the preventive impacts of the IFN-γ-exposed MSCs on body weight loss and EAE-related clinical scores were indicated 34 51 . It has also been reported that priming of MSCs with IFN-γ significantly improves the efficacy of MSC to reduce graft-versus-host disease (GVHD) mortality in mice 27 .…”

“…Moreover, the MOG-stimulated lymph node cells and the MOGstimulated splenocytes from EAE mice treated with IFN-γ-induced MSCs produced lower levels of IFN-γ and IL-17, whereas secrete higher levels of IL-4 and IL-10 compared with control cells from non-induced MSC-treated mice [34]. Thus, IFN-γ-induced MSCs can improve the Th17/Treg and Th1/Th2 imbalances in EAE mice [34]. The results from an in vitro experiment also indicated that IFN-γ promotes the capacity MSCs to induce Treg cell differentiation [55].…”

“…IFNγ-induced MSCs significantly induced the expression of Treg cellrelated markers (FOXP3 and IL-10) in the brain of EAE mice. Moreover, the MOG-stimulated lymph node cells and the MOGstimulated splenocytes from EAE mice treated with IFN-γ-induced MSCs produced lower levels of IFN-γ and IL-17, whereas secrete higher levels of IL-4 and IL-10 compared with control cells from non-induced MSC-treated mice [34]. Thus, IFN-γ-induced MSCs can improve the Th17/Treg and Th1/Th2 imbalances in EAE mice [34].…”

“…The suppressive effects of the IFN-γ-induced MSCs on the expression of Th17- (IL-17 and RORγt) and Th1- (IFN-γ and T-bet) related markers in the brain of EAE mice were also indicated 34 . IFN-γ-induced MSCs significantly induced the expression of Treg cell-related markers (FOXP3 and IL-10) in the brain of EAE mice.…”

Treatment with MDL 72527 Ameliorated Clinical Symptoms, Retinal Ganglion Cell Loss, Optic Nerve Inflammation, and Improved Visual Acuity in an Experimental Model of Multiple Sclerosis

“…Further, the activation of STAT3 signaling, a downstream effector of the ERK pathway, is also regulated by MDL 72527 treatment. STAT3 signaling is demonstrated to be a major player in EAE-induced [ 79 ] tissue damage [ 93 , 94 , 95 , 96 , 97 ]. The impact of MDL 72527 indicated in the present study supports the potential of SMOX inhibition in reducing inflammation, in addition to neuroprotection.…”