scholarly journals Anomalous Role of Tumor Necrosis Factor Alpha in Experimental Enterococcal Infection

2002 ◽  
Vol 70 (12) ◽  
pp. 6628-6637 ◽  
Author(s):  
Christopher J. Papasian ◽  
Richard Silverstein ◽  
Jian Jun Gao ◽  
David M. Bamberger ◽  
David C. Morrison
Keyword(s):  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Potential Contribution ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Factor Alpha ◽  
Necrosis Factor

ABSTRACT The murine d-galactosamine (d-gal) model of tumor necrosis factor alpha (TNF-α) hypersensitization was used as an initial tool to investigate the potential contribution of TNF-α to lethal intraperitoneal (i.p.) infection with Enterococcus faecalis. d-gal sensitized mice to lethal E. faecalis infection, whereas dexamethasone and neutralizing anti-TNF-α antibody protected d-gal-treated, E. faecalis-infected mice, implicating TNF-α in the lethal response to E. faecalis infection in d-gal-treated mice. Circulating TNF-α was undetectable for at least 8 h following i.p. E. faecalis infection, although low peritoneal levels of TNF-α were detected within 3 h, suggesting that localized TNF-α production contributed to the lethal response to E. faecalis infection in d-gal-treated mice. Although i.p. E. faecalis infection failed to induce a detectable systemic TNF-α response, circulating Interleukin-6 (IL-6) was detected within 3 h of infection. IL-6 was also detected in the peritoneum within an hour of infection, prior to the appearance of peritoneal TNF-α. In striking contrast to in vivo results, E. faecalis induced a potent and rapid TNF-α response from both mouse peritoneal macrophages and the RAW 264.7 cell line in vitro. This led us to hypothesize that TNF-α production in response to E. faecalis infection is suppressed by IL-6 in vivo. In vitro experiments demonstrated a statistically significant, but modest, inhibitory effect of IL-6 on TNF-α production by RAW cells stimulated with E. faecalis. Collectively, these data indicate that acute, lethal E. faecalis infection appears to induce an unusual cytokine response that differs in character from that previously described for most other gram-positive and gram-negative bacteria.

scholarly journals Abnormal lymphokine production: a novel feature of the genetic disease Fanconi anemia. II. In vitro and in vivo spontaneous overproduction of tumor necrosis factor alpha

Blood ◽  
1994 ◽  
Vol 83 (5) ◽  
pp. 1216-1225 ◽  
Author(s):  
F Rosselli ◽  
J Sanceau ◽  
E Gluckman ◽  
J Wietzerbin ◽  
E Moustacchi
Keyword(s):  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Fanconi Anemia ◽  
Tumor Necrosis ◽  
Tnf Alpha ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
Necrosis Factor

Abstract We have previously shown an unbalanced cytokine production in Fanconi anemia (FA) cells, ie, an underproduction of interleukin 6 (IL-6) during growth. Among a number of cytokines analyzed, the only other anomalies detected concern tumor necrosis factor alpha (TNF alpha). In comparison to normal cells, this cytokine is overproduced by FA lymphoblasts from the four genetic complementation groups. Indeed, up to an eight-fold increase in TNF alpha is observed in the growth medium of FA cells. Moreover, addition of anti-TNF alpha antibodies partially corrects the FA hypersensitivity to treatment by mitomycin C (MMC). Treatment of FA cells with IL-6, which partially restored an almost normal sensitivity to MMC of FA cells also reduces the TNF alpha overproduction in FA lymphoblasts. No anomalies at the molecular level (Southern and Northern blot analyses) are detected for the TNF alpha gene and its mRNA. We have investigated the in vivo situation by assaying TNF alpha levels in the serum from FA homozygotes and obligate heterozygotes. In contrast to normal healthy donors or to aplastic anemia patients in whom serum TNF alpha is present only in trace amounts, all 36 FA patients and 21 FA parents monitored show a significantly (P < .001) higher level of serum TNF alpha activity. Consequently, abnormal TNF alpha production seems to be associated with the FA genetic background.

scholarly journals Anti-Atherosclerotic Effect of Hibiscus Leaf Polyphenols against Tumor Necrosis Factor-alpha-Induced Abnormal Vascular Smooth Muscle Cell Migration and Proliferation

Antioxidants ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 620 ◽  
Author(s):  
Cheng-Chung Chou ◽  
Chi-Ping Wang ◽  
Jing-Hsien Chen ◽  
Hui-Hsuan Lin
Keyword(s):  
Smooth Muscle ◽  
Cell Migration ◽  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Factor Alpha ◽  
Necrosis Factor

The proliferation and migration of vascular smooth muscle cells (VSMCs) are major events in the development of atherosclerosis following stimulation with proinflammatory cytokines, especially tumor necrosis factor-alpha (TNF-α). Plant-derived polyphenols have attracted considerable attention in the prevention of atherosclerosis. Hibiscus leaf has been showed to inhibit endothelial cell oxidative injury, low-density lipoprotein oxidation, and foam cell formation. In this study, we examined the anti-atherosclerotic effect of Hibiscus leaf polyphenols (HLPs) against abnormal VSMC migration and proliferation in vitro and in vivo. Firstly, VSMC A7r5 cells pretreated with TNF-α were demonstrated to trigger abnormal proliferation and affect matrix metalloproteinase (MMP) activities. Non-cytotoxic doses of HLPs abolished the TNF-α-induced MMP-9 expression and cell migration via inhibiting the protein kinase PKB (also known as Akt)/activator protein-1 (AP-1) pathway. On the other hand, HLP-mediated cell cycle G0/G1 arrest might be exerted by inducing the expressions of p53 and its downstream factors that, in turn, suppress cyclin E/cdk2 activity, preventing retinoblastoma (Rb) phosphorylation and the subsequent dissociation of Rb/E2F complex. HLPs also attenuated reactive oxygen species (ROS) production against TNF-α stimulation. In vivo, HLPs improved atherosclerotic lesions, and abnormal VSMC migration and proliferation. Our data present the first evidence of HLPs as an inhibitor of VSMC dysfunction, and provide a new mechanism for its anti-atherosclerotic activity.

scholarly journals Inhibition of Tumor Necrosis Factor Alpha-Induced NF-κB Activation by the Adenovirus E3-10.4/14.5K Complex

2002 ◽  
Vol 76 (11) ◽  
pp. 5515-5521 ◽  
Author(s):  
Joshua M. Friedman ◽  
Marshall S. Horwitz
Keyword(s):  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Interleukin 1 ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Factor Alpha ◽  
E3 Region ◽  
Necrosis Factor

ABSTRACT Recombinant adenoviruses (Ads) are useful tools in gene transfer because they are able to infect a wide variety of tissues and cell types and do not require a replicating target cell. However, transgene expression is only transient due to host innate and acquired immune responses to the virus. Most recombinant Ads have deletions of early region 3 (E3) genes, allowing more space for insertion of the transgene. Although the E3 region is not necessary for infection, it has been observed that these “nonessential” genes have immunomodulatory properties. We demonstrate here that the E3 region of Ad inhibits the activation of NF-κB induced by tumor necrosis factor alpha (TNF-α) and interleukin-1. Ad E3 is able to prevent NF-κB from entering the nucleus, where it is normally active. Ad E3 also appears to function by preventing the activation of the kinase complex, IKK, which is responsible for phosphorylation of IκB that retains NF-κB in the cytoplasm in an inactive state. The prevention of NF-κB activation has been mapped to a complex of two of the seven E3 products, E3-10.4K and E3-14.5K (RIDα/β). These and other studies indicate that, by using Ad vectors containing the E3 region, it may be possible to reduce the harmful proinflammatory effects of TNF-α and other cytokines that compromise the use of Ad gene therapy vectors in vivo.

Somnogenic, pyrogenic, and anorectic activities of tumor necrosis factor-alpha and TNF-alpha fragments

1992 ◽  
Vol 263 (3) ◽  
pp. R708-R715 ◽  
Author(s):  
L. Kapas ◽  
L. Hong ◽  
A. B. Cady ◽  
M. R. Opp ◽  
A. E. Postlethwaite ◽  
...  
Keyword(s):  
Amino Acid ◽  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Tnf Alpha ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
Necrosis Factor

Exogenously administered tumor necrosis factor-alpha (TNF-alpha) elicits several symptoms of generalized infections such as fever, increased sleep, and anorexia. The aim of the present work was to localize these effects of TNF-alpha to specific amino acid sequences of the parent molecule by characterizing the in vivo and in vitro activities of several synthetic TNF-alpha fragments. Intracerebroventricular injection of TNF-alpha elicited dose-dependent fevers and increases in non-rapid-eye-movement sleep (NREMS) in rabbits. Four fragments also promoted NREMS and five elicited monophasic fevers. All of the somnogenic fragments share the amino acid sequence 31-36. In rats, TNF-alpha and one of the fragments [TNF-alpha-(69-100)] suppressed 12-h food intake. Furthermore, TNF-alpha increased the expression of the intercellular adhesion molecule-1 and enhanced interferon-gamma-induced HLA-DR expression in human glioblastoma cell line. In contrast, none of the fragments possessed these in vitro activities. Our in vivo results support the concept that there are biologically active regions in the TNF-alpha molecule.

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