PLAU and systemic sclerosis: As shown in Figure 1A, patients with SSc had significantly lower uPA concentrations (mean = 3,226 ± 2,444 pg/ml, median = 3,178 pg/ml, range = 6,590 pg/ml) than the healthy controls (mean = 6,957 ± 1,390 pg/ml, median = 6,986 pg/ml, range = 4,614 pg/ml).