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Sphingosine-1-phosphate receptors control B-cell migration through signaling components associated with primary immunodeficiencies, chronic lymphocytic leukemia, and multiple sclerosis

Authors

  • H. Sic
  • H. Kraus
  • J. Madl
  • K.A. Flittner
  • A.L. von Münchow
  • K. Pieper
  • M. Rizzi
  • A.K. Kienzler
  • K. Ayata
  • S. Rauer
  • B. Kleuser
  • U. Salzer
  • M. Burger
  • K. Zirlik
  • V. Lougaris
  • A. Plebani
  • W. Römer
  • C. Loeffler
  • S. Scaramuzza
  • A. Villa
  • E. Noguchi
  • B. Grimbacher
  • H. Eibel

Journal

  • Journal of Allergy and Clinical Immunology

Citation

  • J Allergy Clin Immunol 134 (2): 420-428

Abstract

  • BACKGROUND: Five different G protein-coupled sphingosine-1-phosphate (S1P) receptors (S1P1-S1P5) regulate a variety of physiologic and pathophysiologic processes, including lymphocyte circulation, multiple sclerosis (MS), and cancer. Although B-lymphocyte circulation plays an important role in these processes and is essential for normal immune responses, little is known about S1P receptors in human B cells. OBJECTIVE: To explore their function and signaling, we studied B-cell lines and primary B cells from control subjects, patients with leukemia, patients with S1P receptor inhibitor-treated MS, and patients with primary immunodeficiencies. METHODS: S1P receptor expression was analyzed by using multicolor immunofluorescence microscopy and quantitative PCR. Transwell assays were used to study cell migration. S1P receptor internalization was visualized by means of time-lapse imaging with fluorescent S1P receptor fusion proteins expressed by using lentiviral gene transfer. B-lymphocyte subsets were characterized by means of flow cytometry and immunofluorescence microscopy. RESULTS: Showing that different B-cell populations express different combinations of S1P receptors, we found that S1P1 promotes migration, whereas S1P4 modulates and S1P2 inhibits S1P1 signals. Expression of CD69 in activated B lymphocytes and B cells from patients with chronic lymphocytic leukemia inhibited S1P-induced migration. Studying B-cell lines, normal B lymphocytes, and B cells from patients with primary immunodeficiencies, we identified Bruton tyrosine kinase, β-arrestin 2, LPS-responsive beige-like anchor protein, dedicator of cytokinesis 8, and Wiskott-Aldrich syndrome protein as critical signaling components downstream of S1P1. CONCLUSION: Thus S1P receptor signaling regulates human B-cell circulation and might be a factor contributing to the pathology of MS, chronic lymphocytic leukemia, and primary immunodeficiencies.


DOI

doi:10.1016/j.jaci.2014.01.037