Rice LM, et al. - Authors sought to identify a serum-based proteomic diagnostic biomarker for systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) that would allow for rapid non-invasive screening and could positively impact patient survival. In sera from SSc patients and those with SSc-PAH, a clear delineation between overall protein expression was suggested in the findings. They suggested that the combination of Midkine and Follistatin-like 3 (FSTL3) can serve as an SSc-PAH biomarker and for this rare disease population and this combination is a potential drug target.