PBSCs sphingoling along S1P/S1P1 axis

Abstract

In this issue of Blood, Juarez and colleagues reveal a need for the Sphingosine-1-Phosphate/S1P receptor 1 (S1P/S1P1) axis in the egress of hematopoietic stem cells/hematopoietic progenitor cells (HSCs/HPCs) from the bone marrow after CXCR4 antagonist mediated mobilization in mice.1 The authors also demonstrate an additional peripheral blood stem cell (PBSC) mobilization benefit for S1P1 agonist co-treatment in combination with a CXCR4 antagonist (see figure) but not human granulocyte colony-stimulating factor (G-CSF).