CXCR4 and systemic sclerosis: At T8, fibrocytes showed an adherent spindle-shaped morphology, and FACS analysis demonstrated that the percentage of CD45+COL I+CXCR4+ fibrocytes was significantly higher in both SSc patients and in HSs compared with T0 (up to 52.8 ± 27.1% vs. 1.0 ± 1.2% and up to 61.9 ± 24.4% vs. 0.5 ± 0.2%, respectively) (p < 0.01) (Fig. 1b).