Transforming growth factor (TGF)-beta 1 induced rat IL-2-activated natural killer (IANK) cell chemotaxis. Various doses of cholera toxin (CT) or pertussis toxin (PT) inhibited the activity of TGF-beta 1 suggesting a role for guanine nucleotide binding (G) proteins. ADP-ribosylation assay showed that rat IANK cell membranes possess a 39 kDa PT substrate and two, 41 and 42 kDa, CT substrates. ADP-ribosylation also showed that incubating IANK cell membranes with TGF-beta 1 in the presence of guanosine 5'-O-(3-thiotriphosphate) resulted in the disappearance of the PT substrate. Immunoblot analysis showed that rat IANK cell membranes possess one Gi (39 kDa), one G0 (39 kDa) and three Gs (40, 41, and 42 kDa) proteins. Pretreatment of IANK cell membranes with TGF-beta 1 in the presence of guanosine-5'-O-(3-thiotriphosphate) reduced the intensity of the 39 kDa G(0) and the 40 kDa Gs but not the 39 kDa Gi or the 41 kDa or 42 kDa Gs. Furthermore, TGF-beta 1 stimulated GTP binding and increased GTPase activity in IANK cell membranes. Both activities were inhibited by PT or CT. This inhibition was associated with the modification of G proteins by the toxins suggesting that bacterial toxin substrates are linked to TGF-beta 1 receptors. Our results suggest that G0 and Gs are involved in mediating the chemotactic signal of TGF-beta 1 in rat IANK cells.
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http://dx.doi.org/10.1093/intimm/5.8.825 | DOI Listing |
J Immunol
April 2000
Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
NK cells respond to various chemokines, suggesting that they express receptors for these chemokines. In this paper, we show that IL-2-activated NK (IANK) cells express CC chemokine receptor 4 (CCR4) and CCR8, as determined by flow cytometric, immunoblot, and RNase protection assays. Macrophage-derived chemokine (MDC), the ligand for CCR4, induces the phosphorylation of CCR4 within 0.
View Article and Find Full Text PDFImmunology
December 1998
Department of Anatomy, University of Oslo, Oslo, Norway.
We demonstrate here that the CC chemokines macrophage inflammatory protein-3alpha (MIP-3alpha), macrophage inflammatory protein-3beta (MIP-3beta) and the CX3C chemokine fractalkine induce the chemotaxis of interleukin-2 (IL-2)-activated natural killer (IANK) cells. In addition, these chemokines enhance the binding of [gamma-35S]guanine triphosphate ([gamma-35S]GTP) to IANK cell membranes, suggesting that receptors for these chemokines are G protein-coupled. Our results show that MIP-3alpha receptors are coupled to Go, Gq and Gz, MIP-3beta receptors are coupled to Gi, Gq and Gs, whereas fractalkine receptors are coupled to Gi, and Gz.
View Article and Find Full Text PDFFASEB J
August 1997
Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Norway.
We show here that interferon-inducible protein-10 (IP-10), an ELR lacking CXC chemokine, and the C chemokine lymphotactin (Ltn) induce the chemotaxis and calcium mobilization in IL2-activated NK (IANK) and CC chemokine-activated NK (CHAK) cells. Cross-desensitization experiments show that IP-10 or Ltn use receptors not shared by other C, CC, or CXC chemokines. The chemotaxis induced by either IP-10 or Ltn for both cell types is inhibited upon pretreatment of these cells with pertussis toxin (PT).
View Article and Find Full Text PDFBiochem Biophys Res Commun
July 1997
Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Blindern, Norway.
The CXC chemokine stromal derived factor-1alpha (SDF-1alpha) induces both the chemotaxis and calcium mobilization in IL-2-activated NK (IANK) cells. The ability of SDF-1alpha to induce IANK cell chemotaxis is inhibited upon incorporating antibodies to the alpha subunit of Go and Gq but not Gi, Gs, or Gz, whereas (Ca++)i mobilization is inhibited with anti-Go, [corrected] anti-Gq and anti-Gs, but not with any other anti-G proteins examined. Further analysis showed that antibody to phospholipase C (PLC)beta but not PLCgamma inhibited SDF-1alpha-induced (Ca++)i mobilization, suggesting that this signal is mediated by G protein coupled receptor and not by tyrosine kinase receptors.
View Article and Find Full Text PDFBlood
May 1996
Department of Anatomy, University of Oslo, Norway.
Using two different approaches, we have investigated the types of G proteins coupled to CC chemokine receptors. First, permeabilization of interleukin-2-activated natural killer (IANK) cells with streptolysin-O and introduction of anti-G protein antibodies inside these cells resulted in the following. (1) Anti-G(s), anti-G(o), and anti-G(z) inhibited the migration of IANK cells in response to macrophage-inflammatory protein-1 alpha (MIP-1 alpha), monocyte chemoattractant protein-1 (MCP-1), or regulated on activation normal T cell expressed and secreted (RANTES).
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