W146 is a selective and potent Sphingosine 1-phosphate receptor subtype 1 (S1PR1) antagonist that induces significant but transient hematolymphopenia in mice.W146 induces significant but transient hematolymphopenia in mice, inducing pulmonary edema.

S1P1 receptor:70-80 nM(Ki)

W146 is an antagonist of S1PR1 (Ki: 70-80 nM). [1]
W146 pretreatment significantly increased the TUNEL labeling index of endothelial progenitor cells (EPCs) compared with the S1P-treated group. W146 pretreatment significantly increased the level of activated cleaved caspase-3. S1P was able to reduce apoptosis in EPCs, but this protective effect was completely lost after W146 treatment. [2]

In mice, Injections of W146, W140, JTE013, or Cay10444 do not alter the basal WBC count. when mice are pretreated with W146, it is found that a significant increase in KSL-HSPC mobilization, compared to that in mice pretreated with dextran followed by AMD3100 administration. Moreover, pre-treatment of W146 shows an approximately 8-fold increase of KSL-HSPC mobilization, measured by the CFU-G/M colony-forming assays, compared to that in mice treated with AMD3100 alone. [3]