Altered Expression of Specific Transcription Factors of Th17 (RORγt, RORα) and Treg Lymphocytes (FOXP3) by Peripheral Blood Mononuclear Cells from Patients with Multiple Sclerosis

The imbalance in Th17/Treg cell-related responses plays an important role in the pathogenesis of multiple sclerosis (MS). The development of Th17- and Treg cells is regulated by specific transcription factors-ROR gamma t and ROR alpha-and FOXP3, respectively. The aim was to determine the expression of ROR gamma t, ROR alpha, and FOXP3 in peripheral blood mononuclear cells (PBMCs) from MS patients following in vitro stimulation. The PBMCs from 22 MS patients and 20 healthy subjects were cultured in the presence of 10 mu g/ml MOG, 10 mu g/ml PHA, or without stimulation. The PBMCs were incubated at 37 A degrees C for 24 h, and then the messenger RNA (mRNA) expression of ROR gamma t, ROR alpha, and FOXP3 was determined by real-time PCR. The expression of ROR gamma t and ROR alpha was increased in non-stimulated, MOG-stimulated, and PHA-stimulated PBMCs from MS patients in comparison with same cultures from the healthy group (P < 0.01, P < 0.01, and P < 0.02 for ROR gamma t; P < 0.001, P < 0.001, and P < 0.05, for ROR alpha, respectively). The FOXP3 expression in non-stimulated PBMCs from MS patients was significantly lower than that in equal culture from healthy subjects (P < 0.05). There were no significant differences between healthy subjects and MS patients regarding the expression of FOXP3 mRNA by MOG-stimulated and PHA-stimulated PBMCs. These results showed an imbalance in Th17/Treg cells at transcription factor levels with a deviation toward Th17 cell in MS. The correction of Th17/Treg balance at transcription levels should be considered to design novel therapeutic strategies for MS treatment.