S1PR2 and pulmonary fibrosis: Sphingosine-1-phosphate (S1P) and its receptor S1pr2 have been implicated in pulmonary fibrosis, and they demonstrated that CD11b deficiency inhibits sphingosine 1-phosphate receptor 2 (S1PR2)/sphingosine kinase 2 (SphK2) signaling during pulmonary fibrosis.