Based on the results obtained from the flow cytometry analysis, circulating monocytes were isolated from a group of enrolled SSc patients (11 SSc-ILD patients and 5 SSc patients without ILD) and HSs (n=5), differentiated in vitro to MDMs to evaluate the protein synthesis of TLR4 and M2 cell membrane markers. This evidence concerns the gene TLR4 and systemic sclerosis.