The percentage of circulating CD3+CD31+CXCR4+ Tang cells in total CD3+ T cells was not different between the whole SSc patient cohort (median 29.9, IQR 22.3−36.2) and HC (median 25.2, IQR 23.3−33.5) (Fig 1C). Here, PECAM1 is linked to systemic sclerosis.