Differential utilization of cyclic ADP-ribose pathway by chemokines to induce the mobilization of intracellular calcium in NK cells.

We show here that cyclic adenosine diphosphate-ribose (cADPR) may be a second messenger for chemokines. Extracts collected from NK cells stimulated with IL-8 for 2 min were incubated with beta-NAD for an additional 2 min (designated as IL-8 extracts). This mixture elevated the mobilization of (Ca(2+))(i) in alpha-toxin permeabilized NK cells.

Recruitment of pleckstrin and phosphoinositide 3-kinase gamma into the cell membranes, and their association with G beta gamma after activation of NK cells with chemokines.

The role of phosphoinositide 3 kinases (PI 3-K) in chemokine-induced NK cell chemotaxis was investigated. Pretreatment of NK cells with wortmannin inhibits the in vitro chemotaxis of NK cells induced by lymphotactin, monocyte-chemoattractant protein-1, RANTES, IFN-inducible protein-10, or stromal-derived factor-1 alpha. Introduction of inhibitory Abs to PI 3-K gamma but not to PI 3-K alpha into streptolysin O-permeabilized NK cells also inhibits chemokine-induced NK cell chemotaxis.

MIP-3alpha, MIP-3beta and fractalkine induce the locomotion and the mobilization of intracellular calcium, and activate the heterotrimeric G proteins in human natural killer cells.

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.

Chemokines activate natural killer cells through heterotrimeric G-proteins: implications for the treatment of AIDS and cancer.

Natural killer (NK) cells are anti-tumor and anti-viral effector cells. These cells show increased cytolytic activity upon stimulation with interleukin 2 or chemokines. In addition, members of the C, CC, CXC, or CX3C chemokines induce the in vitro chemotaxis of NK cells and contribute to their in vivo tissue accumulation.

Functional coupling of NKR-P1 receptors to various heterotrimeric G proteins in rat interleukin-2-activated natural killer cells.

NKR-P1 molecules constitute a family of type II membrane receptors in natural killer (NK) cells that preferentially activate NK cell killing and release of interferon-gamma from these cells. Here, we demonstrate that anti-NKR-P1 enhances GTP binding in rat interleukin-2-activated NK cell membranes; GTP binding to Gi3alpha, Gsalpha, Gq,11alpha, and Gzalpha increased noticeably in these cell membranes after treatment with anti-NKR-P1. Western blot analysis of membrane proteins prepared from interleukin-2-activated NK cells reveals the presence of Gi1,2alpha, Gi3alpha, Goalpha, Gsalpha, Gq, 11alpha, Gzalpha, and G12alpha, but not G13alpha.

Interferon-inducible protein-10 and lymphotactin induce the chemotaxis and mobilization of intracellular calcium in natural killer cells through pertussis toxin-sensitive and -insensitive heterotrimeric G-proteins.

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).

Preferential involvement of Go and Gz proteins in mediating rat natural killer cell lysis of allogeneic and tumor target cells.

IL-2-activated NK cells from PVG rats potently lyse target cells expressing allo-MHC class I determinants. Here, we investigated the role that G proteins play in mediating this activity. Pretreatment of NK cells with pertussis toxin (PT) or cholera toxin (CT) inhibited NK cell killing of tumor (YAC-1 or P815), and allogeneic target cells.

Differential coupling of CC chemokine receptors to multiple heterotrimeric G proteins in human interleukin-2-activated natural killer cells.

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).

CC chemokines induce the generation of killer cells from CD56+ cells.

We describe here that members of the CC chemokines exhibit biological activities other than chemotaxis. Macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, monocyte chemoattractant protein-1 and RANTES, but not interleukin (IL)-8, induce the generation of cytolytic cells, designated here as CHAK (CC chemokine-activated killer) cells to distinguish them from IL-2-activated (LAK) cells. Like IL-2, CC chemokines can induce the proliferation and activation of killer cells.

C-C chemokines induce the chemotaxis of NK and IL-2-activated NK cells. Role for G proteins.

The C-C chemokines MIP-1 alpha, MCP-1, and RANTES, but not MIP-1 beta, induce the chemotaxis of NK and IL-2-activated NK (IANK) cells, as determined in microchemotaxis assay. Only RANTES and MCP-1, but not MIP-1 alpha were able to induce the chemokinesis of NK cells. In contrast, none of the C-C chemokines tested was able to induce the chemokinesis of IANK cells.

Gs is the major G protein involved in interleukin-2-activated natural killer (IANK) cell-mediated cytotoxicity. Successful introduction of anti-G protein antibodies inside streptolysin O-permeabilized IANK cells.

In the present work, anti-G protein antibodies were introduced inside streptolysin permeabilized O interleukin-2-activated natural killer (IANK) cells. Successful entry of the antibodies was determined by flow cytometry and fluorescence microscopy. Permeabilized cells showed typical large granular lymphocyte morphology and remained functional, significantly lysing both NK-sensitive K562 cells and NK-resistant/IANK-sensitive RAJI target cells.

Priming effects of granulocyte-macrophage colony-stimulating factor are coupled to cholera toxin-sensitive guanine nucleotide binding protein in human T lymphocytes.

In addition to the mobilization of neutrophils and monocytes, granulocyte-macrophage colony-stimulating factor (GM-CSF) also mobilizes lymphocytes into peripheral blood. We examined the ability of GM-CSF to induce the proliferation of purified human T cells (CD3+ CD4+ CD56- CD16- B1- MO2-) in two major aspects: (1) the mechanisms of GM-CSF interaction with interleukin-2 (IL-2) causing T-cell proliferation, and (2) the intracellular signals transmitted by GM-CSF in T lymphocytes. We observed that concentrations of GM-CSF between 0.

Guanine nucleotide binding proteins mediate the chemotactic signal of transforming growth factor-beta 1 in rat IL-2 activated natural killer cells.

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.

Transforming growth factor-beta 1 is chemotactic for interleukin-2-activated natural killer cells.

We examined the effect of transforming growth factor-beta 1 (TGF-beta 1) on the in vitro motility of interleukin-2-activated natural killer (IANK) cells. Low doses of TGF-beta 1 (0.01 or 0.

IL-8 induces the locomotion of human IL-2-activated natural killer cells. Involvement of a guanine nucleotide binding (Go) protein.

The effect of IL-8 on the in vitro locomotion of human IL-2-activated natural killer (IANK) cells was studied. It was observed that IL-8 induces chemokinesis in these cells, as determined by their migration in modified Boyden chambers. Bacterial toxins such as cholera toxin or pertussis toxin inhibited IL-8-induced chemokinetic activity, suggesting the involvement of guanine nucleotide-binding (G) proteins in IL-8 signal transduction in these cells.

Gallium toxicity and adaptation in Pseudomonas fluorescens.

When cultured in a defined citrate medium supplemented with 1 mM gallium (III) Pseudomonas fluorescens ATCC 13525 experienced a lag phase of 40 h with no apparent diminution in cellular yield. Following initial uptake of the metal-ligand complex, gallium was secreted in the spent fluid. This lag phase was abolished either by inoculating the medium with gallium adapted cells or by inclusion of iron (III) (20 microM) in the growth medium.

Aluminium, chromium and manganese detoxification mechanisms in Pseudomonas syringae: an X-ray fluorescence study.

Pseudomonas syringae cultured in a defined citrate medium supplemented with 1 mM aluminium, chromium and manganese, respectively, appeared to elicit disparate biochemical responses. At the stationary phase of growth aluminium was predominantly present as an insoluble residue. Although virtually none of this metallic element was detected in the supernatant, the bacterial cells appeared to contain some aluminium.

Exocellular and intracellular accumulation of lead in Pseudomonas fluorescens ATCC 13525 is mediated by the phosphate content of the growth medium.

Pseudomonas fluorescens appears to elicit disparate lead detoxification mechanisms in phosphate-rich and phosphate-deficient media. When grown in the presence of 0.1 mM Pb2+ complexed to citrate, the sole source of carbon, only a slight diminution in cellular yield was observed in the former medium.