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WIP regulates signaling via the high affinity receptor for immunoglobulin E in mast cells.

Kettner A, Kumar L, Antón IM, Sasahara Y, de la Fuente M, Pivniouk VI, Falet H, Hartwig JH, Geha RS - J. Exp. Med. (2004)

Bottom Line: Calcium mobilization, phosphorylation of Syk, phospholipase C-g2, and c-Jun NH2-terminal kinase were markedly decreased in WIP-deficient BMMCs.However, the kinetics of actin changes and the cell shape changes that follow FcepsilonRI signaling were altered in WIP-deficient BMMCs.These results suggest that WIP regulates FcepsilonRI-mediated mast cell activation by regulating Syk levels and actin cytoskeleton rearrangement.

View Article: PubMed Central - PubMed

Affiliation: Division of Immunology, Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.

ABSTRACT
Wiskott-Aldrich syndrome protein-interacting protein (WIP) stabilizes actin filaments and is important for immunoreceptor-mediated signal transduction leading to actin cytoskeleton rearrangement in T and B cells. Here we report a role for WIP in signaling pathways downstream of the high affinity receptor for immunoglobulin (Ig)E (FcepsilonRI) in mast cells. WIP-deficient bone marrow-derived mast cells (BMMCs) were impaired in their capacity to degranulate and secrete interleukin 6 after FcepsilonRI ligation. Calcium mobilization, phosphorylation of Syk, phospholipase C-g2, and c-Jun NH2-terminal kinase were markedly decreased in WIP-deficient BMMCs. WIP was found to associate with Syk after FcepsilonRI ligation and to inhibit Syk degradation as evidenced by markedly diminished Syk levels in WIP-deficient BMMCs. WIP-deficient BMMCs exhibited no apparent defect in their subcortical actin network and were normal in their ability to form protrusions when exposed to an IgE-coated surface. However, the kinetics of actin changes and the cell shape changes that follow FcepsilonRI signaling were altered in WIP-deficient BMMCs. These results suggest that WIP regulates FcepsilonRI-mediated mast cell activation by regulating Syk levels and actin cytoskeleton rearrangement.

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In vivo IgE-dependent histamine release and in vitro degranulation is diminished in WIP−/− mice. (A) WIP−/− mice and WT controls were sensitized with 3 mg IgE by i.v. injection in the retro-orbital vein. 24 h later the mice were challenged with i.v. injection of HSA-DNP. Blood histamine levels were determined by competitive RIA in plasma collected 1.5 min after antigen challenge. (B) IgE-mediated in vitro degranulation of WIP−/− BMMCs. Release of β-hexosaminidase. BMMCs preloaded with IgE were stimulated with F(ab′)2 anti–rat Ig at indicated concentrations. Results represent mean ± SD of three experiments from two independently derived WT and WIP−/− cell lines, each analyzed in duplicates. Statistical analysis was performed using the Student's t test.
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fig2: In vivo IgE-dependent histamine release and in vitro degranulation is diminished in WIP−/− mice. (A) WIP−/− mice and WT controls were sensitized with 3 mg IgE by i.v. injection in the retro-orbital vein. 24 h later the mice were challenged with i.v. injection of HSA-DNP. Blood histamine levels were determined by competitive RIA in plasma collected 1.5 min after antigen challenge. (B) IgE-mediated in vitro degranulation of WIP−/− BMMCs. Release of β-hexosaminidase. BMMCs preloaded with IgE were stimulated with F(ab′)2 anti–rat Ig at indicated concentrations. Results represent mean ± SD of three experiments from two independently derived WT and WIP−/− cell lines, each analyzed in duplicates. Statistical analysis was performed using the Student's t test.

Mentions: Adoptive transfer of IgE antibodies to normal mice primes them to undergo passive systemic anaphylactic reactions in response to intravenous challenge with specific antigen. IgE-mediated anaphylaxis is dependent both on mast cells and FcεRI signaling as it is diminished in mast cell–deficient W/Wv mice (28, 29), virtually absent in mast cell–deficient Sl/Sld mice (30), and dramatically reduced in FcεRIα-deficient mice (31). Dramatic increase of plasma concentration of histamine, a major vasoactive mediator released by activated mast cells and basophils, has been shown to correlate with systemic anaphylaxis (32). To evaluate whether expression of WIP is important in regulating IgE-dependent systemic release of histamine, we passively sensitized four WIP−/− mice and six control littermates with mouse IgE anti-DNP mAb. 24 h later, mice were challenged with DNP-HSA and plasma histamine concentration was determined before and 1.5 min after challenge with antigen (Fig. 2 A). Plasma histamine levels before antigen administration were comparable in WT and WIP−/− mice. After antigen challenge, the increase in plasma histamine concentration was dramatic in WT mice but minimal in WIP−/− mice (Fig. 2 A). This finding suggests that WIP is essential for IgE-mediated systemic anaphylaxis in mice.


WIP regulates signaling via the high affinity receptor for immunoglobulin E in mast cells.

Kettner A, Kumar L, Antón IM, Sasahara Y, de la Fuente M, Pivniouk VI, Falet H, Hartwig JH, Geha RS - J. Exp. Med. (2004)

In vivo IgE-dependent histamine release and in vitro degranulation is diminished in WIP−/− mice. (A) WIP−/− mice and WT controls were sensitized with 3 mg IgE by i.v. injection in the retro-orbital vein. 24 h later the mice were challenged with i.v. injection of HSA-DNP. Blood histamine levels were determined by competitive RIA in plasma collected 1.5 min after antigen challenge. (B) IgE-mediated in vitro degranulation of WIP−/− BMMCs. Release of β-hexosaminidase. BMMCs preloaded with IgE were stimulated with F(ab′)2 anti–rat Ig at indicated concentrations. Results represent mean ± SD of three experiments from two independently derived WT and WIP−/− cell lines, each analyzed in duplicates. Statistical analysis was performed using the Student's t test.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2211794&req=5

fig2: In vivo IgE-dependent histamine release and in vitro degranulation is diminished in WIP−/− mice. (A) WIP−/− mice and WT controls were sensitized with 3 mg IgE by i.v. injection in the retro-orbital vein. 24 h later the mice were challenged with i.v. injection of HSA-DNP. Blood histamine levels were determined by competitive RIA in plasma collected 1.5 min after antigen challenge. (B) IgE-mediated in vitro degranulation of WIP−/− BMMCs. Release of β-hexosaminidase. BMMCs preloaded with IgE were stimulated with F(ab′)2 anti–rat Ig at indicated concentrations. Results represent mean ± SD of three experiments from two independently derived WT and WIP−/− cell lines, each analyzed in duplicates. Statistical analysis was performed using the Student's t test.
Mentions: Adoptive transfer of IgE antibodies to normal mice primes them to undergo passive systemic anaphylactic reactions in response to intravenous challenge with specific antigen. IgE-mediated anaphylaxis is dependent both on mast cells and FcεRI signaling as it is diminished in mast cell–deficient W/Wv mice (28, 29), virtually absent in mast cell–deficient Sl/Sld mice (30), and dramatically reduced in FcεRIα-deficient mice (31). Dramatic increase of plasma concentration of histamine, a major vasoactive mediator released by activated mast cells and basophils, has been shown to correlate with systemic anaphylaxis (32). To evaluate whether expression of WIP is important in regulating IgE-dependent systemic release of histamine, we passively sensitized four WIP−/− mice and six control littermates with mouse IgE anti-DNP mAb. 24 h later, mice were challenged with DNP-HSA and plasma histamine concentration was determined before and 1.5 min after challenge with antigen (Fig. 2 A). Plasma histamine levels before antigen administration were comparable in WT and WIP−/− mice. After antigen challenge, the increase in plasma histamine concentration was dramatic in WT mice but minimal in WIP−/− mice (Fig. 2 A). This finding suggests that WIP is essential for IgE-mediated systemic anaphylaxis in mice.

Bottom Line: Calcium mobilization, phosphorylation of Syk, phospholipase C-g2, and c-Jun NH2-terminal kinase were markedly decreased in WIP-deficient BMMCs.However, the kinetics of actin changes and the cell shape changes that follow FcepsilonRI signaling were altered in WIP-deficient BMMCs.These results suggest that WIP regulates FcepsilonRI-mediated mast cell activation by regulating Syk levels and actin cytoskeleton rearrangement.

View Article: PubMed Central - PubMed

Affiliation: Division of Immunology, Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.

ABSTRACT
Wiskott-Aldrich syndrome protein-interacting protein (WIP) stabilizes actin filaments and is important for immunoreceptor-mediated signal transduction leading to actin cytoskeleton rearrangement in T and B cells. Here we report a role for WIP in signaling pathways downstream of the high affinity receptor for immunoglobulin (Ig)E (FcepsilonRI) in mast cells. WIP-deficient bone marrow-derived mast cells (BMMCs) were impaired in their capacity to degranulate and secrete interleukin 6 after FcepsilonRI ligation. Calcium mobilization, phosphorylation of Syk, phospholipase C-g2, and c-Jun NH2-terminal kinase were markedly decreased in WIP-deficient BMMCs. WIP was found to associate with Syk after FcepsilonRI ligation and to inhibit Syk degradation as evidenced by markedly diminished Syk levels in WIP-deficient BMMCs. WIP-deficient BMMCs exhibited no apparent defect in their subcortical actin network and were normal in their ability to form protrusions when exposed to an IgE-coated surface. However, the kinetics of actin changes and the cell shape changes that follow FcepsilonRI signaling were altered in WIP-deficient BMMCs. These results suggest that WIP regulates FcepsilonRI-mediated mast cell activation by regulating Syk levels and actin cytoskeleton rearrangement.

Show MeSH
Related in: MedlinePlus