Background Although a number of cytokines and chemokines have been investigated as possible mediators of fibrosis in Systemic Sclerosis (SSc), specific correlation between cytokines and organ involvement have not been found yet, and a cytokine profile characteristic of SSc is far to be identified.
Objectives Establish a profile of anti and profibrotic molecules involved in skin fibrosis of SSc patients.
Methods The mRNA expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR) in skin's biopsies from 14 patients: 7 patients with cutaneous diffuse SSc (dSSc) and 7 patients with cutaneous limited SSc (lSSc), and 5 sex and age-matched controls. All patients with SSc were biopsied at a lesional forearm site, and met the American College of Rheumatology (ACR) criteria for the classification of SSc. The transcriptome of samples extracted from skin biopsies of SSc and healthy controls was observed using quantitative real-time-polymerase chain reaction (qRT-PCR) of eleven molecules: TGF-b, PDGF, CTGF, CCL3, IL-6, IL-13, IL-7, IFNg, IL-17, IL-22, and RORc
Results The CCL3, IL-13, IFN-g and IL-7 were more expressed in the SSc's skin (respectively, p=0.0002, p=0.0243, p=0.0335, p=0.0082) when compared with healthy controls. We found positive correlation in expression levels between CCL3 and IL-7 (p=0.0050 r =0.7187), besides a negative correlation between IL-7 and TGF-b (p=0,0136 r = -0,6527). Furthermore, we obtained relation with some clinical manifestation and the relative genes expression.
Conclusions We demonstrated that the relative mRNA expression of IL-7, IFN-g, CCL3 e IL-13 were increased on the microenvironment of the SS's skin when compared with the healthy controls. Our study suggests interesting correlation between IL-7 and CCL3, so we propose large studies with SSc to establish the real role of these two molecules. Furthermore, we also ratified the potential probability antifibrotic role of IL-7 as well IFN-g.
Acknowledgements We thank Dr. Emerson Andrade Lima for performing the skin biopsies
Disclosure of Interest None declared