Sphingosine 1 Phosphate Lyase 1 (SGPL1) is an enzyme that plays a crucial role in lipid metabolism. It specifically catalyzes the cleavage of sphingosine-1-phosphate (S1P) into phosphoethanolamine and hexadecenal, regulating the levels of S1P in cells. S1P is a bioactive sphingolipid that acts as a signaling molecule, influencing various cellular processes such as cell migration, proliferation, survival, and differentiation. By modulating S1P levels, SGPL1 plays a vital role in maintaining cellular homeostasis and participating in various physiological and pathological processes.Besides,Ephrin A5 (EFNA5) has been identified as an interactor of SGPL1, thus a functional binding ELISA assay was conducted to detect the interaction of recombinant human SGPL1 and recombinant human EFNA5. Briefly, SGPL1 was diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to EFNA5-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-SGPL1 pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody for 1h at 37℃, wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50 μL stop solution to the wells and read at 450/630nm immediately. The binding activity of recombinant human SGPL1 and recombinant human EFNA5 was shown in Figure 1, the EC50?for this effect is 1.15ug/mL.