The flow cytometry analysis showed that the percentage of circulating hybrid TLR4+M2 monocytes (CD1c-CD80-TLR4+CD163+CD204+CD206+cells) as well as M2 monocytes (CD1c-CD80-TLR4-CD163+CD204+CD206+cells) in the leukocyte population were observed significantly increased in SSc patients compared to HSs (p<0.001) (Figure 1). This evidence concerns the gene TLR4 and systemic sclerosis.