FPR1 and acute basophilic leukemia: The mechanism by which the cyclic peptide [SRSRY] interferes with fMLF binding to FPR1 has been investigated in rat basophilic leukaemia RBL-2H3/ETFR cells expressing high levels of constitutively activated FPR1: [SRSRY] inhibits fMLF- induced, FPR1-mediated cell migration by blocking both internalization and fMLF- and SRSRY-uptake of FPR1 [25].