SELP and idiopathic pulmonary fibrosis: Stimulation with all concentrations of ADP led to greater increases in platelet P-selectin expression in IPF patients compared with controls (ADP 0.1 μM: 1.9%±0.5 positive platelets versus 0.7%±0.1; p = 0.03; ADP 1 μM: 9.8%±1.3 versus 3.3%±0.8; p = <0.01; ADP 10 μM: 41.3%±4.2 versus 22.5%±2.6; p = <0.01).