Regarding the possibility that Treg provide information on the clinical course of MS, a recent study based on Helios expression (a transcription factor that defines nTreg) indicated that progressive MS patients (both PPMS and SPMS) had more pTreg (FoxP3+Helios−CD25hiCD127−) than RRMS patients. This evidence concerns the gene FOXP3 and myeloid sarcoma.