The mechanism underling this effect was shown by Jorres et al. [19] that found that iloprost reduces TNF α transcriptional activity and decreases TNF α mRNA stability in human peripheral blood mononuclear leukocytes stimulated with LPS; Our study is the first evaluation of the effect of iloprost on TNF α production and T cell subsets in SSc. Here, TNF is linked to systemic sclerosis.