Since a selective ETA inhibition, such as the one obtained with ambrisentan, seems to accelerate pulmonary disease, we may suggest that an imbalanced expression of ET-1 receptors with a diminished expression of ETA on immune cells may predispose SSc patients to develop ILD possibly through an increased ETB-mediated stimulation on T cells. The gene discussed is EDNRA; the disease is systemic sclerosis.