With regards to the prevalence of S1PR3-aAb, a higher fraction of samples from the SSc-PAH was identified as positive (16/58, 27.6%) in comparison to the SSc w/o PAH group (18/100, 18.0%), albeit without reaching statistical significance (P=0.1133) (Figure 4C). Here, S1PR3 is linked to pulmonary arterial hypertension.