Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

ZnCl2 over a very narrow concentration range was found to be mitogenic for hamster lymph node cells but not for thymocytes or splenocytes. Maximal leucine, [3H]uridine, and [3H]thymidine incorporation. Addition of 10 micron ZnCl2 was found to greatly enhance the stimulation observed with the B-lymphocyte mitogen lipopolysaccharide but not with dextran sulfate or the T-lymphocyte mitogen lipopolysaccharide but not with dextran sulfate or the T-lymphocyte mitogen concanavalin A. Although not mitogenic for splenocytes, 10 to 25 micron ZnCl2 slightly enhanced lipopolysaccharide stimulation but not concanavalin A or dextran sulfate stimulation. The effect of ZnCl2 on lipopolysaccharide stimulation was also confirmed with outbred Hartley guinea pig splenocytes and lymph node cells. Zinc chloride (50 micron) was mitogenic for both of these tissues; the response to lipopolysaccharide was enhanced by addition of 50 micron ZnCl2, but the concanavalin A response was unaffected. The possibility that the zinc effect is mediated by proteolytic mechanisms is discussed.
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PMID:Effect of zinc chloride on hamster lymphoid cells: mitogenicity and differential enhancement of lipopolysaccharide stimulation of lymphocytes. 34 10

The influence of zinc on the in vitro antibody response to antigen or mitogen stimulation was studied by adding various concentrations of ZnCl2 to cultures of spleen cells stimulated with sheep erythrocytes, trinitrophenyl-lipopolysaccharide or with the polyclonal B cell activator E. coli lipopolysaccharide (LPS). Addition of ZnCl2 in concentrations ranging from 10(-8) or 10(-7) to 10(-5) M increased the specific antibody response to antigens or the polyclonal antibody synthesis induced by stimulation with LPS, when the response of the assayed population in the control cultures without ZnCl2 was low, as observed in cultures without 2-mercaptoethanol (2-ME). However, in cultures supplemented with 2-ME, the potentiating effect of ZnCl2 diminished or disappeared or even the antibody response was inhibited. Higher concentrations of ZnCl2 markedly depressed (5 X 10(-5) M) or abolished (10(-4)) the in vitro induced antibody response in all cultures. The various mechanisms which could mediate the effects of zinc are discussed.
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PMID:Modulation by zinc of the in vitro antibody response to T-dependent and T-independent antigens. 660 99

1. Metal salts can inhibit cell activity through direct toxicity to critical cellular molecules and structures. On the other hand, they can also change cell behaviour by inducing specific genes (including genes encoding members of the metallothionein [MT] gene family). Therefore, transition metals may affect cell functions either by acting as a toxin, or by transmitting or influencing signals controlling gene expression. 2. To explore the latter possibility, we measured the ability of low, non-toxic metal pretreatment to alter immune cell behaviour. We previously found that pretreatment of human monocytes with zinc induces metallothionein gene expression and alters their capacity to undergo a bacterial lipopolysaccharide-induced respiratory burst. We showed here that cadmium and mercury salts, at concentrations that exert no discernible toxicity, inhibit activation of human monocytic leukemia (THP-1) cells. CdCl2 1 microM, ZnCl2 20-40 microM or HgCl2 2 microM pretreatment for 20 h induced MT-2 mRNA and total MT protein accumulation and had no effect on proliferation potential or metabolic activity, but significantly inhibited the ability of subsequent lipopolysaccharide treatment to induce the oxidative burst, increased adhesion to plastic, and MT-2 and interleukin-1 beta (IL-1 beta) mRNA accumulation. 3. The phenomenon of metal-induced suppression of monocyte activation, at metal concentrations that have no effect on cell viability, has important implications for assessment of acceptable levels of human exposure to cadmium, zinc and mercury.
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PMID:Effect of non-toxic mercury, zinc or cadmium pretreatment on the capacity of human monocytes to undergo lipopolysaccharide-induced activation. 913 84

We analyzed the influence of heavy-metal ions on human umbilical vein endothelial cells (HUVEC) in comparison to proinflammatory cytokines (TNF-alpha, IL-1beta) and lipopolysaccharide (LPS). Adhesion molecule and cytokine expressions are upregulated by heavy-metal exposure. Expression of E-selectin on the cell surface was strongly induced by 1-mM concentrations of NiCl2 and CoCl2, whereas ZnCl2 and CrCl3 had no influence. Furthermore, it is shown that NiCl2 induces mRNA expression of E-selectin, intercellular adhesion molecule-1, IL-6 and IL-8 in a 1-mM concentration. The transcription factor NF-kappaB is known to be involved in the regulation of adhesion molecule expression in endothelial cells after activation by proinflammatory cytokines. We demonstrated that treatment of HUVEC with Ni2+ and Co2+ ions induces the translocation of NF-kappaB p65 and also p50 into the nucleus. NF-kappaB binding activity is enhanced under the influence of heavy metals as determined by mobility shift analysis. P65 and p50 are components of the NF-kappaB complexes as confirmed by supershift analysis. We could show that activation at the protein level is accompanied by induction of NF-kappaB p65 mRNA expression. HUVEC also express the NF-kappaB inhibitor I kappaB-alpha (MAD-3). In the early phase of activation by Ni2+ and Co2+ ions, disappearance of I kappaB-alpha in the cytoplasm accompanied p65 translocation, followed by its gradual reappearence. Because I kappaB mRNA could be upregulated by NiCl2 as well as by a mixture of cytokines, we suggest that the replenishment of the inhibitor in the cytoplasm is caused by de novo I kappaB gene expression. In addition to the enhanced DNA-binding activity of NF-kappaB, another transcription factor, AP-1, was also augmented in HUVEC stimulated by NiCl2, CoCl2 or by proinflammatory mediators and the phorbol ester PMA. Fos protein is shown to be a component of the activated AP-1 complex, as determined by supershift analysis, suggesting that it consists of Jun/Fos heterodimers.
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PMID:Heavy metal ion induction of adhesion molecules and cytokines in human endothelial cells: the role of NF-kappaB, I kappaB-alpha and AP-1. 945 94