Lysophospholipids control integrin-dependent adhesion in splenic B cells through G(i) and G(12)/G(13) family G-proteins but not through G(q)/G(11)

J Biol Chem. 2006 Dec 1;281(48):36985-92. doi: 10.1074/jbc.M605287200. Epub 2006 Oct 4.

Abstract

Integrin-mediated adhesion is a crucial step in lymphocyte extravasation and homing. We show here that not only the chemokines CXCL12 and CXCL13 but also the lysophospholipids sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA) enhance adhesion of murine follicular and marginal zone B cells to ICAM-1 in vitro. This process involves clustering of integrin LFA-1 and is blocked by pertussis toxin, suggesting that G(i) family G-proteins are involved. In addition, lysophospholipid-induced adhesion on ICAM-1 depends on Rho and Rhokinase, indicative of an involvement of G(12)/G(13), possibly also G(q)/G(11) family G-proteins. We used G(12)/G(13)- or G(q)/G(11)-deficient B cells to study the role of these G-protein families in lysophospholipid-induced adhesion and found that the pro-adhesive effects of LPA and S1P are completely abrogated in G(12)/G(13)-deficient marginal zone B cells, reduced in G(12)/G(13)-deficient follicular B cells, and normal in G(q)/G(11)-deficient B cells. We also show that loss of lysophospholipid-induced adhesion results in disinhibition of migration in response to the follicular chemokine CXCL13, which might contribute to the abnormal localization of splenic B cell populations observed in B cell-specific G(12)/G(13)-deficient mice in vivo. Taken together, this study shows that lysophospholipids regulate integrin-mediated adhesion of splenic B cells to ICAM-1 through G(i) and G(12)/G(13) family G-proteins but not through G(q)/G(11).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • B-Lymphocytes / metabolism*
  • Cell Adhesion
  • GTP-Binding Protein alpha Subunits, G12-G13 / chemistry
  • GTP-Binding Protein alpha Subunits, G12-G13 / physiology
  • GTP-Binding Protein alpha Subunits, Gq-G11 / chemistry
  • GTP-Binding Protein alpha Subunits, Gq-G11 / physiology
  • GTP-Binding Proteins / metabolism*
  • Integrins / metabolism*
  • Intercellular Adhesion Molecule-1 / metabolism
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Lysophospholipids / metabolism
  • Lysophospholipids / physiology*
  • Mice
  • Mice, Inbred C57BL
  • Protein Serine-Threonine Kinases / metabolism
  • Sphingosine / analogs & derivatives
  • Sphingosine / metabolism
  • Spleen / cytology*
  • Spleen / metabolism
  • rho GTP-Binding Proteins / metabolism
  • rho-Associated Kinases

Substances

  • Integrins
  • Intracellular Signaling Peptides and Proteins
  • Lysophospholipids
  • Intercellular Adhesion Molecule-1
  • sphingosine 1-phosphate
  • Protein Serine-Threonine Kinases
  • rho-Associated Kinases
  • GTP-Binding Proteins
  • GTP-Binding Protein alpha Subunits, G12-G13
  • GTP-Binding Protein alpha Subunits, Gq-G11
  • rho GTP-Binding Proteins
  • Sphingosine
  • lysophosphatidic acid