scholarly journals Construction of a ribozyme directed against human interleukin-6 mRNA: evaluation of its catalytic activity in vitro and in vivo

Blood ◽  
1994 ◽  
Vol 84 (11) ◽  
pp. 3758-3765 ◽  
Author(s):  
M Mahieu ◽  
R Deschuyteneer ◽  
D Forget ◽  
P Vandenbussche ◽  
J Content

We have designed a ribozyme (Rz) that cleaves human interleukin-6 (IL- 6) mRNA in vivo. This Rz was tested in vitro, and was found to give expected size fragments. It was then incorporated into a mammalian expression vector containing the constitutive cytomegalovirus (CMV) immediate early promoter and transfected into human U amniotic cells (UAC). Cell clones that stably express this catalytic RNA have been obtained. Some of them displayed a marked reduction of tumor necrosis factor (TNF)-induced IL-6 production. Their reduced ability to express IL-6 was related to the amount of Rz they produced and to the extent of IL-6 mRNA cleavage as observed by a ribonuclease protection assay. These data provide a method to study further the role of IL-6 production in various biologic situations, and suggest the feasibility of developing Rzs directed against various cytokines to study their biologic role and mechanism of action.

2004 ◽  
Vol 50 (11) ◽  
pp. 2136-2140 ◽  
Author(s):  
Marie Bennermo ◽  
Claes Held ◽  
Sten Stemme ◽  
Carl-Göran Ericsson ◽  
Angela Silveira ◽  
...  

Abstract Background: A single-nucleotide polymorphism (SNP) in the promoter region of the interleukin-6 (IL-6) gene at position −174 (G>C) has been reported to be associated with a variety of major diseases, such as Alzheimer disease, atherosclerosis, and cardiovascular disease, cancer, non-insulin-dependent diabetes mellitus, osteoporosis, sepsis, and systemic-onset juvenile chronic arthritis. However, authors of previous in vitro and in vivo studies have reported conflicting results regarding the functionality of this polymorphism. We therefore aimed to clarify the role of the −174 SNP for the induction of IL-6 in vivo. Methods: We vaccinated 20 and 18 healthy individuals homozygous for the −174 C and G alleles, respectively, with 1 mL of Salmonella typhii vaccine. IL-1β, IL-6, and tumor necrosis factor-α (TNF-α) were measured in the blood at baseline and up to 24 h after vaccination. Results: Individuals with the G genotype had significantly higher plasma IL-6 values at 6, 8, and 10 h after vaccination than did individuals with the C genotype (P <0.005). There were no differences between the two genotypes regarding serum concentrations of IL-1β and TNF-α before or after vaccination. Conclusions: The −174 G>C SNP in the promoter region of the IL-6 gene is functional in vivo with an increased inflammatory response associated with the G allele. Considering the central role of IL-6 in a variety of major diseases, the present finding might be of major relevance.


Blood ◽  
1992 ◽  
Vol 80 (1) ◽  
pp. 194-202 ◽  
Author(s):  
E Shacter ◽  
GK Arzadon ◽  
J Williams

Abstract Intraperitoneal (i.p.) injection of a mineral oil such as pristane induces a chronic inflammatory response in mice. This is characterized by a large influx of macrophages and other inflammatory cells into the peritoneal cavity for months after injection of the oil. By using the B9 cell bioassay, it was found that injection of pristane caused a marked and prolonged elevation of interleukin-6 (IL-6) levels in the peritoneal cavities of the mice. IL-6 was undetectable (less than 15 U/mL) in the peritoneal fluids of unprimed mice and during the first week after injecting pristane. From 4 to 20 weeks, the concentration of IL-6 increased to an apparent plateau with concentrations ranging from 200 to 2,000 U/mL. Increasing the dose of pristane did not substantially increase the peritoneal levels of IL-6 established at 20 weeks after pristane treatment. At later times (by day 250), the level decreased to 263 +/- 217 U/mL. However, mice that developed plasma cell tumors around day 300 showed high levels of IL-6 in the ascites fluid (650 to 2,400 U/mL). Serum levels of IL-6 were also elevated in pristane-primed mice but were substantially lower than those found in the peritoneal cavity. Chronic administration of the nonsteroidal anti- inflammatory drug indomethacin decreased the levels of IL-6 by 75% to 80%. Experiments performed in vitro showed that pristane-elicited macrophages secreted low levels of IL-6 constitutively and high levels of IL-6 in the presence of lipopolysaccharide. Both IL-6 and prostaglandin E2 production were inhibited by addition of indomethacin to macrophage cultures in vitro. Treatment of mice with pristane may provide a model system for studying the inflammatory pathways that control IL-6 levels in vivo. The relevance of these results to elucidation of the role of IL-6 in plasma cell tumorigenesis is discussed.


1998 ◽  
Vol 188 (11) ◽  
pp. 1985-1992 ◽  
Author(s):  
Azumi Hamasaki ◽  
Fujiro Sendo ◽  
Keiko Nakayama ◽  
Noriko Ishida ◽  
Izumi Negishi ◽  
...  

To elucidate the role of A1, a new member of the Bcl-2 family of apoptosis regulators active in hematopoietic cell apoptosis, we established mice lacking A1-a, a subtype of the A1 gene in mice (A1-a−/− mice). Spontaneous apoptosis of peripheral blood neutrophils of A1-a−/− mice was enhanced compared with that of either wild-type mice or heterozygous mutants (A1-a+/− mice). Neutrophil apoptosis inhibition induced by lipopolysaccharide treatment in vitro or transendothelial migration in vivo observed in wild-type mice was abolished in both A1-a−/− and A1-a+/− animals. On the other hand, the extent of tumor necrosis factor α–induced acceleration of neutrophil apoptosis did not differ among A1-a−/−, A1-a+/−, and wild-type mice. The descending order of A1 mRNA expression was wild-type, A1-a+/−, and A1-a−/−. Taken together, these results suggest that A1 is involved in inhibition of certain types of neutrophil apoptosis.


2005 ◽  
Vol 25 (5) ◽  
pp. 2000-2013 ◽  
Author(s):  
Niklas Finnberg ◽  
Joshua J. Gruber ◽  
Peiwen Fei ◽  
Dorothea Rudolph ◽  
Anka Bric ◽  
...  

ABSTRACT DR5 (also called TRAIL receptor 2 and KILLER) is an apoptosis-inducing membrane receptor for tumor necrosis factor-related apoptosis-inducing ligand (also called TRAIL and Apo2 ligand). DR5 is a transcriptional target of p53, and its overexpression induces cell death in vitro. However, the in vivo biology of DR5 has remained largely unexplored. To better understand the role of DR5 in development and in adult tissues, we have created a knockout mouse lacking DR5. This mouse is viable and develops normally with the exception of having an enlarged thymus. We show that DR5 is not expressed in developing embryos but is present in the decidua and chorion early in development. DR5-null mouse embryo fibroblasts expressing E1A are resistant to treatment with TRAIL, suggesting that DR5 may be the primary proapoptotic receptor for TRAIL in the mouse. When exposed to ionizing radiation, DR5-null tissues exhibit reduced amounts of apoptosis compared to wild-type thymus, spleen, Peyer's patches, and the white matter of the brain. In the ileum, colon, and stomach, DR5 deficiency was associated with a subtle phenotype of radiation-induced cell death. These results indicate that DR5 has a limited role during embryogenesis and early stages of development but plays an organ-specific role in the response to DNA-damaging stimuli.


2017 ◽  
Vol 214 (4) ◽  
pp. 905-917 ◽  
Author(s):  
Yochai Wolf ◽  
Anat Shemer ◽  
Michal Polonsky ◽  
Mor Gross ◽  
Alexander Mildner ◽  
...  

Monocytes are circulating mononuclear phagocytes, poised to extravasate to sites of inflammation and differentiate into monocyte-derived macrophages and dendritic cells. Tumor necrosis factor (TNF) and its receptors are up-regulated during monopoiesis and expressed by circulating monocytes, as well as effector monocytes infiltrating certain sites of inflammation, such as the spinal cord, during experimental autoimmune encephalomyelitis (EAE). In this study, using competitive in vitro and in vivo assays, we show that monocytes deficient for TNF or TNF receptors are outcompeted by their wild-type counterpart. Moreover, monocyte-autonomous TNF is critical for the function of these cells, as TNF ablation in monocytes/macrophages, but not in microglia, delayed the onset of EAE in challenged animals and was associated with reduced acute spinal cord infiltration of Ly6Chi effector monocytes. Collectively, our data reveal a previously unappreciated critical cell-autonomous role of TNF on monocytes for their survival, maintenance, and function.


1992 ◽  
Vol 1 (5) ◽  
pp. 347-353 ◽  
Author(s):  
Andrew C. Issekutz ◽  
Nancy Lopes ◽  
Thomas B. Issekutz

The cytokines IL-1 and TNF-α are involved in inflammation and their production is stimulated by various agents, especially endotoxin (LPS). Here, using the human IL-1 receptor antagonist (IL-1RA) and a new monoclonal antibody (mAb 7F11) to rabbit TNF, the role of endogenous IL-l and TNF production in acute (3h) leukocyte (PMNL) recruitment to dermal inflammation in rabbits has been studied. IL-1RA inhibited by 27% the PMNL accumulation in reactions induced by killed Escherichia coli (p < 0.05) but not by LPS. The monoclonal antibody to TNF inhibited by 27% and 38% (p < 0.002) the PMNL accumulation in LPS and E. coli reactions respectively, but a combination of the mAb with IL-1RA was not more effective. Treatment of human umbilical vein endothelium with LPS for 3 h activated endothelium to induce PMNL transendothelial migration in vitro, which was not inhibited by IL-1RA, antibody to TNF-α, IL-1 or to IL-8. In conclusion, TNF and IL-1 may partially mediate acute PMNL infiltration in vivo to LPS and Gram negative bacteria, but there is a major IL-1/TNF independent mechanism, at least in dermal inflammation, which may be due to direct LPS activation of the microvasculature or perhaps the generation of cytokines other than IL-1 and TNF.


2013 ◽  
Vol 66 (1) ◽  
pp. 121-129 ◽  
Author(s):  
Kazuhiro Yokota ◽  
Kojiro Sato ◽  
Takashi Miyazaki ◽  
Hideki Kitaura ◽  
Hisako Kayama ◽  
...  

Blood ◽  
2003 ◽  
Vol 102 (5) ◽  
pp. 1740-1742 ◽  
Author(s):  
Ingrid Pollet ◽  
Christy J. Opina ◽  
Carla Zimmerman ◽  
Kevin G. Leong ◽  
Fred Wong ◽  
...  

AbstractThe intracellular pathways by which inflammatory mediators transmit their angiogenic signals is not well studied. The effects of a potent inflammatory mediator, bacterial lipopolysaccharide (LPS), are transmitted through Toll-like receptors (TLRs). A major, although not exclusive, LPS/TLR intracellular signaling pathway is routed through TNF (tumor necrosis factor) receptor associated factor 6 (TRAF6). In this report we demonstrate that LPS directly stimulates endothelial sprouting in vitro. By blocking TRAF6 activity using retroviral expression of a dominant-negative TRAF6 in endothelial cells, we show that TRAF6 is absolutely required for the LPS-initiated angiogenic response in vitro and in vivo. Inhibition of either c-Jun N-terminal kinase (JNK) activity or nuclear factor κB (NF-κB) activity, downstream of TRAF6, is sufficient to inhibit LPS-induced endothelial sprouting. In contrast, only inhibition of NF-κB, but not JNK, activity blocks basic fibroblast growth factor (bFGF)–induced angiogenesis. Our findings thus demonstrate a direct endothelial-stimulatory role of LPS in initiating angiogenesis through activation of TRAF6-dependent signaling pathways.


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