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K W Moore

Publications and source records attributed to K W Moore.

At least 19 recordsLinked to original sources
PubMed2000

Stat3-dependent induction of p19INK4D by IL-10 contributes to inhibition of macrophage proliferation.

We have previously reported that IL-10 inhibits proliferation of normal bone marrow-derived macrophages and of the monocyte/macrophage cell line J774. Activation of Stat3 was shown to be necessary and sufficient to mediate inhibition of proliferation. To investigate further the mechanism of growth arrest, we examined the effect of IL-10 on expression of cell cycle inhibitors. We found that IL-10 treatment increases expression of the cyclin-dependent kinase inhibitors p19INK4D and p21CIP1 in macrophages. IL-10 cannot induce p19INK4D expression or block proliferation when Stat3 signaling is blocked by a dominant negative Stat3 or a mutant IL-10Ralpha which does not recruit Stat3 in J774 cells, whereas p21CIP1 induction is not affected. An inducibly active Stat3 (coumermycin-dimerizable Stat3-Gyrase B), which suppresses J774 cell proliferation, also induced p19INK4D expression. Sequencing of the murine p19INK4D promoter revealed two candidate Stat3 binding sites, and IL-10 treatment activated a reporter gene controlled by this promoter. These data suggest that Stat3-dependent induction of p19INK4D mediates inhibition of proliferation. Enforced expression of murine p19INK4D cDNA J774 cells significantly reduced their proliferation. Use of antisense p19INK4D and analysis of p19INK4D-deficient macrophages confirmed that p19INK4D is required for optimal inhibition of proliferation by IL-10, and indicated that additional IL-10 signaling events contribute to this response. These data indicate that Stat3-dependent induction of p19INK4D and Stat3-independent induction of p21CIP1 are important components of the mechanism by which IL-10 blocks proliferation in macrophages.

Amino Acid Sequence↗
PubMed2000

Sedative but not anxiolytic properties of benzodiazepines are mediated by the GABA(A) receptor alpha1 subtype.

Inhibitory neurotransmission in the brain is largely mediated by GABA(A) receptors. Potentiation of GABA receptor activation through an allosteric benzodiazepine (BZ) site produces the sedative, anxiolytic, muscle relaxant, anticonvulsant and cognition-impairing effects of clinically used BZs such as diazepam. We created genetically modified mice (alpha1 H101R) with a diazepam-insensitive alpha1 subtype and a selective BZ site ligand, L-838,417, to explore GABA(A) receptor subtypes mediating specific physiological effects. These two complimentary approaches revealed that the alpha1 subtype mediated the sedative, but not the anxiolytic effects of benzodiazepines. This finding suggests ways to improve anxiolytics and to develop drugs for other neurological disorders based on their specificity for GABA(A) receptor subtypes in distinct neuronal circuits.

Allosteric Site↗
PubMed1999

1-(3-Cyanobenzylpiperidin-4-yl)-5-methyl-4-phenyl-1, 3-dihydroimidazol-2-one: a selective high-affinity antagonist for the human dopamine D(4) receptor with excellent selectivity over ion channels.

After the requirement of pseudocycle formation in the ureas 3 and 7 for hD(4) binding and selectivity was confirmed, structural hybridization with the known hD(4) ligand 2 led to the design and identification of the lead 4-(2-oxo-1, 3-dihydroimidazol-2-yl)piperidine 8. Optimization studies were carried out on 8 with the aim of achieving 1000-fold selectivity for hD(4) over all other receptors while retaining the good pharmacokinetic properties of the lead. After initial preparation of 8 as a minor component in a low-yielding reaction, a novel and regioselective "four-step/one-pot" procedure was developed which proved to be applicable to rapid investigation of the SAR of the 1, 3-dihydroimidazol-2-one ring. Various changes to substituents attached to the 3-, 4-, or 5-position of the 1, 3-dihydroimidazol-2-one core of 8 did not significantly improve selectivity for hD(4) over hD(2) and hD(3). Greater selectivity (>1000-fold) was ultimately achieved by meta substitution of the benzyl group of 8 with various substituents. Compounds 28, 31, and 32 all possess the required selectivity for hD(4) over the other dopamine subtypes, but only 32 has >1000-fold selectivity over all the key counterscreens we tested against. Compound 32 is an antagonist at hD(4) and has a good pharmacokinetic profile in the rat, with excellent estimated in vivo receptor occupancy, thus making it a potentially useful pharmacological tool to investigate the role of the D(4) receptor.

Animals↗
PubMed1998

IL-10 inhibits macrophage activation and proliferation by distinct signaling mechanisms: evidence for Stat3-dependent and -independent pathways.

Interleukin-10 (IL-10) limits inflammatory responses by inhibiting macrophage activation. In macrophages, IL-10 activates Stat1 and Stat3. We characterized IL-10 responses of the J774 mouse macrophage cell line, and of J774 cells expressing wild-type hIL-10R, mutant hIL-10R lacking two membrane-distal tyrosines involved in recruitment of Stat3 (hIL-10R-TyrFF), a truncated Stat3 (DeltaStat3) which acts as a dominant negative, or an inducibly active Stat3-gyraseB chimera (Stat3-GyrB). A neutralizing anti-mIL-10R monoclonal antibody was generated to block the function of endogenous mIL-10R. IL-10 inhibited proliferation of J774 cells and of normal bone marrow-derived macrophages, but not J774 cells expressing hIL-10RTyrFF. Dimerization of Stat3-GyrB by coumermycin mimicked the effect of IL-10, and expression of DeltaStat3 blocked the anti-proliferative activity of IL-10. For macrophage de-activation responses, hIL10R-TyrFF could not mediate inhibition of lipopolysaccharide-induced TNFalpha, IL-1beta or CD86 expression, while DeltaStat3 did not interfere detectably with these IL-10 responses. Thus signals mediating both anti-proliferative and macrophage de-activation responses to IL-10 require the two membrane-distal tyrosines of IL-10R, but Stat3 appears to function only in the anti-proliferative response.

Animals↗
PubMed1997

Altered immune responses in interleukin 10 transgenic mice.

Interleukin (IL)-10 is a pleiotropic cytokine which inhibits a broad array of immune parameters including T helper cell type 1 (Th1) cytokine production, antigen presentation, and antigen-specific T cell proliferation. To understand the consequences of altered expression of IL-10 in immune models of autoimmune disease, the response to infectious agents, and the response to tumors, we developed transgenic mice expressing IL-10 under the control of the IL-2 promoter. Upon in vitro stimulation, spleen cells from unimmunized transgenic mice secrete higher levels of IL-10 and lower amounts of IFN-gamma than do controls, although no gross abnormalities were detected in lymphocyte populations or serum Ig levels. Transfer of normally pathogenic CD4(+) CD45RBhigh splenic T cells from IL-10 transgenic mice did not cause colitis in recipient severe combined immunodeficiency mice. Furthermore, co-transfer of these transgenic cells with CD4(+) CD45RBhigh T cells from control mice prevented disease. Transgenic mice retained their resistance to Leishmania major infection, indicating that their cell-mediated immune responses were not globally suppressed. Lastly, in comparison to controls, IL-10 transgenic mice were unable to limit the growth of immunogenic tumors. Administration of blocking IL-10 mAbs restored in vivo antitumor responses in the transgenic mice. These results demonstrate that a single alteration in the T cell cytokine profile can lead to dramatic changes in immune responses in a manner that is stimulus dependent. These mice will be useful in defining differences in inflammatory conditions and cellular immunity mediated by IL-10.

Animals↗
PubMed1997

Crystal structure of Epstein-Barr virus protein BCRF1, a homolog of cellular interleukin-10.

The crystal structure of Epstein-Barr virus protein BCRF1, an analog of cellular interleukin-10 (IL-10), has been determined at the resolution of 1.9 A and refined to an R-factor 0.191. The structure of this cytokine is similar to that of human IL-10 (hIL-10), forming an intercalated dimer of two 17 kDa polypeptides related by a crystallographic 2-fold symmetry axis. BCRF1 exhibits novel conformations of the N-terminal coil and of the loop between helices A and B compared to hIL-10. These regions are likely to be involved in binding of one or more components of the IL-10 receptor system, and thus the structural differences may account for the lower binding affinity and limited spectrum of biological activities of viral IL-10, compared to hIL-10.

Amino Acid Sequence↗
PubMed1997

4-substituted-3-phenylquinolin-2(1H)-ones: acidic and nonacidic glycine site N-methyl-D-aspartate antagonists with in vivo activity.

4-Substituted-3-phenylquinolin-2(1H)-ones have been synthesized and evaluated in vitro for antagonist activity at the glycine site on the NMDA (N-methyl-D-aspartate) receptor and in vivo for anticonvulsant activity in the DBA/2 strain of mouse in an audiogenic seizure model. 4-Amino-3-phenylquinolin-2(1H)-one (3) is 40-fold lower in binding affinity but only 4-fold weaker as an anticonvulsant than the acidic 4-hydroxy compound 1. Methylsulfonylation at the 4-position of 3 gives an acidic compound (6, pKa = 6.0) where affinity is fully restored but in vivo potency is significantly reduced (Table 1). Methylation at the 4-position of 1 to give 18 results in the abolition of measurable affinity, but the attachment of neutral hydrogen bond-accepting groups to the methyl group of 18 produces compounds with comparable in vitro and in vivo activity to 1 (e.g., 23 and 28, Table 2). Replacement of the 4-hydroxy group of 1 with an ethyl group abolishes activity (42), but again, incorporation of neutral hydrogen bond acceptors to the terminal carbon atom restores affinity (e.g., 36, 39, and 40, Table 3). Replacement of the 4-hydroxy group of the high-affinity compound 2 with an amino group produces a compound with 200-fold reduced affinity (43; IC50 = 0.42 microM, Table 4) which is nevertheless still 10-fold higher in affinity than 3. The results in this paper indicate that anionic functionality is not an absolute requirement for good affinity at the glycine/NMDA site and provide compelling evidence for the existence of a ligand/receptor hydrogen bond interaction between an acceptor attached to the 4-position of the ligand and a hydrogen bond donor attached to the receptor.

Aminoquinolines↗
PubMed1997

The EBV IL-10 homologue is a selective agonist with impaired binding to the IL-10 receptor.

BCRF1 is an EBV homologue of human IL-10 (hIL-10) and is known as viral IL-10 (vIL-10). As found earlier for the effects of vIL-10 on mouse mast cells and CD4+ T cells, the efficiency of inhibition by vIL-10 of IL-2 production by human CD4+ T cell clones is approximately 1000-fold diminished compared with hIL-10. We studied the interaction of vIL-10 and an epitope-tagged homologue, vIL-10His6, with recombinant mouse and human IL-10 receptors (mIL-10R, hIL-10R). vIL-10His6 has approximately 1000-fold lower affinity for recombinant IL-10R than does hIL-10, yet stimulates proliferation of mouse Ba/F3 (BaF)-mIL-10R- and human TF1-hIL-10R-transfected cells with a sp. act. comparable to or greater than that of the cellular cytokine. In contrast, BaF-hIL-10R cells are approximately 1000-fold less sensitive to vIL-10His6 than are BaF-mIL-10R cells. An anti-hIL-10R mAb (3F9) blocks responses to both hIL-10 and vIL-10His6, while a soluble form of hIL-10R effectively neutralizes biologic responses only to hIL-10 by both BaF-IL-10R transfectants and normal human peripheral blood cells. The results indicate that biologic responses to both hIL-10 and vIL-10 require the known IL-10R, and suggest the existence of at least one additional IL-10R subunit. We suggest that vIL-10 is a selective agonist that is impaired in its ability to bind the defined IL-10R, which we now designate as IL-10R alpha.

Animals↗
PubMed1997

Follicular dendritic cells specifically express the long CR2/CD21 isoform.

This paper describes an antibody (mAb 7D6) that specifically recognizes human follicular dendritic cells (FDCs). By expression cloning, a cDNA clone encoding for the long human CR2/ CD21 isoform (CD21L) that contains an additional exon (10a) was isolated. We demonstrated that FDCs selectively express CD21L, while B cells selectively express the short CR2/CD21 lacking exon 10a (CD21S). By screening mouse Ltk- cells transfected with the CD21L cDNA, we further showed that the other two anti-human FDC mAbs DRC-1 and KiM4 also recognize CD21L. Thus, CD21L represents the first characterized human FDC-specific molecule, which may confer unique functions of FDCs in germinal center development.

Animals↗
PubMed1997

A review of the effects of bromate on aquatic organisms and toxicity of bromate to oyster (Crassostrea gigas) embryos.

A critical literature review has been undertaken of the effects that bromate (BrO3-) has on aquatic organisms. Chronic (multigeneration) studies using four marine phytoplankton species indicate a stimulation of cell division at concentrations up to 13.6 mg BrO3- liter-1, such that the EC50 is > 13.6 mg BrO3- liter-1 (exposure period unspecified). No published data were available for any freshwater algal or phytoplankton species. For freshwater invertebrates, the available data are limited to acute studies using two species: the water flea, Daphnia magna, with a 48-h LC50 of 179 mg BrO3- liter-1; and the planarian ("flatworm"), Polycelis nigra, with a 48-h LC50 of 2258 mg BrO3- liter-1. For saltwater invertebrates, there is a greater variety in the spread of species sensitivity to bromate. For crustaceans, the lowest reported acute value is a 24-h LC50 of 176 mg BrO3- liter-1 for mysid shrimp. For molluscs, the published data are somewhat contradictory, with different workers reporting EC50 values to oyster embryo-larvae of either 0.05-0.1 or 30 mg BrO3- liter-1. Following repeated attempts to resolve these differences using the Pacific oyster (Crassostrea gigas) embryo development assay, a 24-h EC50 of 170 mg BrO3- liter-1 was observed. Reported 96-h LC50 values for juvenile saltwater fish range from 427 to 512 mg BrO3- liter-1, while a 10-day LC50 of 279 mg BrO3- liter-1 is also reported. For fish early lifestages, newly hatched larvae are more sensitive than embryo hatching, with a larval 96-h LC50 of 31 mg BrO3- liter-1 being observed. Less severe effects have been reported for older larvae (pro-larvae), for which a 96-h LC50 of 404 mg BrO3- liter-1 is reported. In conclusion, a number of studies provide evidence for the acute toxicity of bromate to invertebrates and fish in the lowest region of 30 mg BrO3- liter-1. Applying the factor of 10 used to extrapolate from acute to potential chronic toxicity, the available data suggest that to protect aquatic organisms from long-term adverse effects, concentrations should not exceed approximately 3.0 mg BrO3- liter-1.

Animals↗
PubMed1996

Stat3 recruitment by two distinct ligand-induced, tyrosine-phosphorylated docking sites in the interleukin-10 receptor intracellular domain.

Recent work has shown that IL-10 induces activation of the JAK-STAT signaling pathway. To define the mechanism underlying signal transducer and activator of transcription (STAT) protein recruitment to the interleukin 10 (IL-10) receptor, the STAT proteins activated by IL-10 in different cell populations were first defined using electrophoretic mobility shift assays. In all cells tested, IL-10 activated Stat1 and Stat3 and induced the formation of three distinct DNA binding complexes that contained different combinations of these two transcription factors. IL-10 also activated Stat5 in Ba/F3 cells that stably expressed the murine IL-10 receptor. Using a structure-function mutagenesis approach, two tyrosine residues (Tyr427 and Tyr477) in the intracellular domain of the murine IL-10 receptor were found to be redundantly required for receptor function and for activation of Stat3 but not for Stat1 or Stat5. Twelve amino acid peptides encompassing either of these two tyrosine residues in phosphorylated form coprecipitated Stat3 but not Stat1 and blocked IL-10-induced Stat3 phosphorylation in a cell-free system. In contrast, tyrosine-phosphorylated peptides containing Tyr374 or Tyr396 did not interact with Stat3 or block Stat3 activation. These data demonstrate that Stat3 but not Stat1 or Stat5 is directly recruited to the ligand-activated IL-10 receptor by binding to specific but redundant receptor intracellular domain sequences containing phosphotyrosine. This study thus supports the concept that utilization of distinct STAT proteins by different cytokine receptors is dependent on the expression of particular ligand-activatable, tyrosine-containing STAT docking sites in receptor intracellular domains.

Acute-Phase Proteins↗
PubMed1995

Viral interleukin 10 (IL-10), the human herpes virus 4 cellular IL-10 homologue, induces local anergy to allogeneic and syngeneic tumors.

After the cloning of murine cytokine synthesis inhibitory factor, it was recognized that a homologous open reading frame was encoded within the Epstein-Barr virus (human herpes virus 4). This viral protein has now been termed viral interleukin 10 (vIL-10) to reflect its protein sequence homology to "cellular" IL-10 (cIL-10, either murine or human IL-10). It is now widely accepted that vIL-10 shares many functions with cIL-10, principally, the ability to enhance survival of newly infected B cells and to diminish the production of IFN-gamma and IL-2 during ongoing immune reactions. The immunomodulatory effect of locally secreted vIL-10 and murine IL-10 (mIL-10) was examined in tumor models using CL8-1 (a BL6 melanoma cell line transfected with the H-2Kb class I gene) in syngeneic animals. Although parental BL6 tumor cells grow in immunocompetent syngeneic hosts, CL8-1 are rejected. To achieve local secretion of vIL-10, we generated vIL-10 retroviral vectors. While nontransduced CL8-1 cells (1 x 10(4)) failed to grow when injected intradermally in C57BL/6 mice, CL8-1 cells (1 x 10(4)) transduced with vIL-10 formed palpable tumors and eventually killed 80% of injected animals. Suppression of tumor rejection was also noted when CL8-1 tumors with or without vIL-10 transfection were admixed with syngeneic vIL-10-transfected fibroblasts and inoculated. Since the in vitro proliferation of the tumor was not altered after transduction with the vIL-10 gene and injection of vIL-10-transduced CL8-1 does not affect the rejection of nontransduced CL8-1 inoculated at a distant site, local vIL-10 secretion appears to suppress the process of immune rejection of the target cells in a dose-dependent manner. Similar results were observed for the H-2b MCA105 sarcoma tumor model in allogeneic BALB/c mice (H-2d). Although all animals that received nontransfected MCA105 rapidly rejected these tumors, MCA105 sarcomas transfected with vIL-10 remained palpable for up to 37 d. The local immunosuppressive effect of gene-delivered vIL-10 could be neutralized by anti-human IL-10 monoclonal antibody or could be reversed by the systemic administration of IL-2 or IL-12. In marked contrast, mIL-10 transfection of CL8-1 significantly suppressed tumor growth and frequently led to the rejection of tumor. Similar results were obtained for the murine tumor cell lines MCA102.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1995

The human interleukin-10 receptor gene maps to chromosome 11q23.3.

The human interleukin-10 receptor (IL-10R) gene has previously been mapped to chromosome 11. Here, we have determined the precise location of the human IL-10R gene by the fluorescence in situ hybridization method, and have found that the IL-10R gene maps to chromosome 11q23.3.

Chromosome Mapping↗
PubMed1995

Cranial cruciate ligament rupture in the dog--a retrospective study comparing surgical techniques.

Three surgical techniques, grouped as intra-articular techniques, extracapsular techniques and fibular head transposition, were used for repair of the cranial cruciate ligament (CCL)-deficient stifle in 113 dogs over a 4 year 4 month period. The clinical outcome of the techniques were compared using information provided by the owners and physical examination. Regardless of surgical technique, 85.7 to 91.0% of dogs showed clinical improvement after surgery. However, less than 50% of dogs became clinically sound on the operated leg and 9.0 to 14.3% of dogs remained persistently lame on the operated leg. No statistical association was found between result after surgery and age, body weight, sex, duration of injury before surgery, association with injury, tibial plateau angle, degree of radiographic osteoarthritis before surgery or the presence of concurrent medial meniscal injury. On physical examination, extra-capsular techniques appeared superior to the fibular head transposition in terms of joint stability and limb function. Concurrent medial meniscal injury necessitating meniscectomy existed in 48.0% of cases. Twenty-two percent of dogs ruptured their contralateral CCL at an average of 14 months after the first.

Animals↗
PubMed1995

Functional regions of the mouse interleukin-10 receptor cytoplasmic domain.

The functions of wild-type and mutant mouse interleukin-10 receptors (mIL-10R) expressed in murine Ba/F3 cells were studied. As observed previously, IL-10 stimulates proliferation of IL-10R-expressing Ba/F3 cells. Accumulation of viable cells in the proliferation assay is to a significant extent balanced by concomitant cell death. Moreover, growth in IL-10 also induces a previously unrecognized response, differentiation of the cells, as evidenced both by formation of large clusters of cells in cultures with IL-10 and by induction or enhancement of expression of several cell surface antigens, including CD32/16, CD2, LECAM-1 (v-selectin), and heat-stable antigen. Two distinct functional regions near the C terminus of the mIL-10R cytoplasmic domain which mediate proliferation were identified; one of these regions also mediates the differentiation response. A third region proximal to the transmembrane domain was identified; removal of this region renders the cell 10- to 100-fold more sensitive to IL-10 in the proliferation assay. In cells expressing both wild-type and mutant IL-10R, stimulation with IL-10 leads to tyrosine phosphorylation of the kinases JAK1 and TYK2 but not JAK2 or JAK3 under the conditions tested.

Animals↗
PubMed1994

Lymphotactin: a cytokine that represents a new class of chemokine.

In this study, the cytokine-producing profile of progenitor T cells (pro-T cells) was determined. During screening of a complementary DNA library generated from activated mouse pro-T cells, a cytokine designated lymphotactin was discovered. Lymphotactin is similar to members of both the Cys-Cys and Cys-X-Cys chemokine families but lacks two of the four cysteine residues that are characteristic of the chemokines. Lymphotactin is also expressed in activated CD8+ T cells and CD4-CD8- T cell receptor alpha beta + thymocytes. It has chemotactic activity for lymphocytes but not for monocytes or neutrophils. The gene encoding lymphotactin maps to chromosome one. Taken together, these observations suggest that lymphotactin represents a novel addition to the chemokine superfamily.

Amino Acid Sequence↗
PubMed1994

Expression cloning and characterization of a human IL-10 receptor.

cDNA clones encoding a human IL-10R (hIL-10R) from a Burkitt lymphoma cell line, BJAB, express a 90 to 110 kDa polypeptide in COS7 cells that binds hIL-10 specifically. The predicted amino acid sequence of hIL-10R is 60% identical and 73% similar to mouse IL-10R (mIL-10R). rIL-10R expressed in an IL-3-dependent mouse pro-B cell line (Ba/F3) binds hIL-10 with high affinity (200 to 250 pM), and the transfected cells exhibit a proliferative response to hIL-10. Mouse IL-10 does not bind to hIL-10R, and hIL-10R-expressing Ba/F3 cells do not respond to the mouse cytokine, observations consistent with the known species specificity of IL-10. Expression of hIL-10R mRNA seems to be restricted mainly to human hemopoietic cells and cell lines. In a number of human T cell clones, expression of hIL-10R mRNA is down-regulated after activation of the cells with anti-CD3 Ab and phorbol ester. The hIL-10R gene is on human chromosome 11. Like mIL-10R, hIL-10R is structurally related to IFNR. Because IL-10 inhibits macrophage activation by IFN-gamma, this relationship suggests possible shared receptor or signal transduction pathway components.

Amino Acid Sequence↗