S1PR1 and rheumatoid arthritis: Although S1PR1 blockade has selective antiinflammatory effects on non-EC cell types, S1PR1 antagonism is not likely a tenable approach in patients with RA, because treatment with NIBR-0213 during AIA results in pulmonary leakage, inflammation, and fibrosis and patients with RA have a high incidence of clinical and subclinical interstitial lung disease (40).