A role for S1P and S1P1 in immature-B cell egress from mouse bone marrow.
B lymphocyte egress from secondary lymphoid organs requires sphingosine-1-phosphate (S1P) and S1P receptor-1 (S1P1). However, whether S1P contributes to immature-B cell egress from the bone marrow (BM) has not been fully assessed. Here we report that in S1P- and S1P1-conditionally deficient mice, the number of immature-B cells in the BM parenchyma increased, while it decreased in the blood. Moreover, a slower rate of bromodeoxyuridine incorporation suggested immature-B cells spent longer in the BM of mice in which S1P1-S1P signaling was genetically or pharmacologically impaired. Transgenic expression of S1P1 in developing B cells was sufficient to mobilize pro- and pre-B cells from the BM. We conclude that the S1P1-S1P pathway contributes to egress of immature-B cells from BM, and that this mechanism is partially redundant with other undefined pathways.
Pereira
João Pedro
JP
Department of Microbiology and Immunology, University of California San Francisco, San Francisco, California, United States of America. Joao.Pereira@ucsf.edu
Xu
Ying
Y
Cyster
Jason G
JG
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D001853:Bone Marrow / Q000378:metabolism*; D001973:Bromodeoxyuridine / Q000378:metabolism; D002465:Cell Movement / Q000187:drug effects; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D005260:Female; D000068876:Fingolimod Hydrochloride; D007166:Immunosuppressive Agents / Q000494:pharmacology; D008246:Lysophospholipids / Q000378:metabolism / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D018345:Mice, Knockout; D008822:Mice, Transgenic; D054448:Precursor Cells, B-Lymphoid / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D011409:Propylene Glycols / Q000494:pharmacology; D049349:Receptors, Lysosphingolipid / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology
D007166:Immunosuppressive Agents; D008246:Lysophospholipids; D011409:Propylene Glycols; D049349:Receptors, Lysosphingolipid; C060506:sphingosine 1-phosphate; D001973:Bromodeoxyuridine; D000068876:Fingolimod Hydrochloride; D013110:Sphingosine