PRSS23 and systemic sclerosis: This includes increased expression of PRSS23 and other genes by SFRP2hi fibroblasts, but also a shift within the population of APOEhi/CCL19/C7 fibroblasts, which show strikingly upregulated expression of a distinct series of genes like CCL19 not upregulated in SSc SFRP2hi fibroblasts.