Systemic Sclerosis and Jak Inhibitors : Emphasis on Macrophages

Systemic sclerosis is a fibrotic and inflammatory chronic autoimmune disorder with no disease modifiying drug available to date. JAK inhibitors may represent a relevant therapeutic candidate for this disease;

The primary objective of this study is to characterize the impact of Ruxolitinib (a JAK ½ inhibitor) on the prof-fibrotic properties of MDM from SSc patients in vitro.

The primary outcome will be the concentration of CCL18 evaluate by ELISA in the condition media of MDM from SSc patients pre treated or not in vitro by ruxolitinib.

The secondary objectives :

1. To characterize the impact of ruxolitinib on other pro-inflammatory or pro-fibrotic cytokines
2. To characterize the impact of ruxolitinib on membrane expression of macrophagic polarization markers of MDM from SSc patients
3. To evaluate the impact of ruxolitinib on the phenotype of MDM from healthy donors exposed in vitro to the serum of SSc patients.
4. To determine the variability of the effects of ruxolitinib on MDM of SSc patients depending on key clinical characteristics (diffuse versus limited SSc, patients with or without Interstitial Lung disease ILD)