scholarly journals Lipopolysaccharide-induced selective priming effects on tumor necrosis factor alpha and nitric oxide production in mouse peritoneal macrophages.

1993 ◽  
Vol 177 (2) ◽  
pp. 511-516 ◽  
Author(s):  
X Zhang ◽  
D C Morrison
Keyword(s):  
Tumor Necrosis ◽  
Peritoneal Macrophages ◽  
Tnf Alpha ◽  
No Production ◽  
Necrosis Factor Alpha ◽  
Priming Effects ◽  
Alpha Production ◽  
Factor Alpha ◽  
Mouse Peritoneal Macrophages ◽  
Necrosis Factor

Preculture of thioglycollate-elicited C3HeB/FeJ mouse peritoneal macrophages in vitro with subthreshold stimulatory concentrations of lipopolysaccharide (LPS) can induce hyporesponsiveness (desensitization) to both tumor necrosis factor alpha (TNF-alpha) and nitric oxide (NO) production when these cells are subsequently stimulated with 100 ng/ml of LPS. We have established, however, that the primary dose of LPS required for inducing downregulation of NO production is significantly lower than that required for inducing downregulation of TNF-alpha production. Further, when LPS-pretreated macrophages become refractory to subsequent LPS stimulation for NO production, the secondary LPS-stimulated TNF-alpha production is markedly enhanced, and vice versa. These results indicate that LPS-induced TNF-alpha and NO production by macrophages are differentially regulated, and that the observed desensitization process may not reflect a state in which macrophages are totally refractory to subsequent LPS stimulation. Rather, our data suggest that LPS-pretreated macrophages become selectively primed for differential responses to LPS. The LPS-induced selective priming effects are not restricted to LPS stimulation, but extend as well to stimuli such as zymosan, Staphylococcus aureus, and heat-killed Listeria monocytogenes.

scholarly journals Polymorphisms in the tumor necrosis factor alpha (TNF-alpha) gene correlate with murine resistance to development of toxoplasmic encephalitis and with levels of TNF-alpha mRNA in infected brain tissue.

1992 ◽  
Vol 175 (3) ◽  
pp. 683-688 ◽  
Author(s):  
Y R Freund ◽  
G Sgarlato ◽  
C O Jacob ◽  
Y Suzuki ◽  
J S Remington
Keyword(s):  
Brain Tissue ◽  
Tumor Necrosis ◽  
Toxoplasmic Encephalitis ◽  
Tnf Alpha ◽  
Necrosis Factor Alpha ◽  
Alpha Production ◽  
D Region ◽  
Factor Alpha ◽  
Alpha Gene ◽  
Necrosis Factor

Murine resistance to development of toxoplasmic encephalitis (TE) has recently been mapped to the D region of the major histocompatibility complex (H-2). Since the gene for tumor necrosis factor alpha (TNF-alpha) is located 5' of the D region and TNF-alpha has been implicated as playing a role in neurological diseases, we were interested in determining the relationship of TNF-alpha production to TE resistance. We have demonstrated that resistance to TE in inbred mice can be correlated with specific restriction fragment length polymorphisms and microsatellite variants in the TNF-alpha gene. Mice that are susceptible to TE express elevated levels of TNF-alpha mRNA in brain tissue 6 wk after infection with the ME49 strain of Toxoplasma gondii. Resistant mice and all mice that are uninfected show no detectable TNF-alpha mRNA expression in brain tissue. Differences in the TNF-alpha gene between susceptible and resistant mice have been localized to the first intron, the promoter, and the 3' end of the TNF-alpha gene. These data implicate differences in regulation of TNF-alpha production in brain tissue as contributing to differences in susceptibility to development of TE.

scholarly journals Macrophage priming and lipopolysaccharide-triggered release of tumor necrosis factor alpha during graft-versus-host disease.

1992 ◽  
Vol 175 (2) ◽  
pp. 405-413 ◽  
Author(s):  
F P Nestel ◽  
K S Price ◽  
T A Seemayer ◽  
W S Lapp
Keyword(s):  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Acute Gvhd ◽  
Tnf Alpha ◽  
Triggered Release ◽  
Necrosis Factor Alpha ◽  
Alpha Production ◽  
Factor Alpha ◽  
Necrosis Factor

In this report we have investigated macrophage (M phi) activity and tumor necrosis factor alpha (TNF-alpha) production during graft-vs.-host disease (GVHD). TNF-alpha production by M phi requires two signals: priming of M phi by interferon followed by triggering of TNF-alpha production and release by lipopolysaccharide (LPS). The state of M phi activation was examined in nonirradiated B6AF1 recipient mice injected with either 60 x 10(6) (acute GVHD) or 30 x 10(6) (nonlethal GVHD) parental B6 lymphoid cells. During the early phase of acute GVHD, administration of normally sublethal amounts of LPS-triggered release of significant amounts of TNF-alpha into the serum resulting in death of the animals within 36 h. Normal animals treated with the same dose of LPS neither died nor produced detectable amounts of serum TNF-alpha. In vitro studies demonstrated that M phi were primed during GVHD. The level of M phi priming was greater during acute GVHD than nonlethal GVHD since 100-fold less LPS was required to trigger killing of a TNF-alpha-sensitive cell line by M phi from acute GVHD animals. The amount of TNF-alpha released into the serum after LPS injection increased during the course of the GVHD and was significantly greater in acute GVH-reactive mice. Endogenous LPS was detected in the serum of acute GVH-reactive animals coincident with the onset of mortality. The data provide evidence that during GVHD M phi are primed as a result of the allogeneic reaction and that endogenous LPS therefore triggers M phi production of TNF-alpha resulting in the symptoms characteristic of acute GVHD.

scholarly journals Induction of tumor necrosis factor alpha production by human hepatocytes in chronic viral hepatitis.

1994 ◽  
Vol 179 (3) ◽  
pp. 841-848 ◽  
Author(s):  
R González-Amaro ◽  
C García-Monzón ◽  
L García-Buey ◽  
R Moreno-Otero ◽  
J L Alonso ◽  
...  
Keyword(s):  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Kupffer Cells ◽  
Human Liver ◽  
Tumor Necrosis ◽  
Tnf Alpha ◽  
Necrosis Factor Alpha ◽  
Alpha Production ◽  
Factor Alpha ◽  
Necrosis Factor

Tumor necrosis factor alpha (TNF-alpha) is a multifunctional cytokine that has an important role in the pathogenesis of inflammation, cachexia, and septic shock. Although TNF-alpha is mainly produced by macrophages, there is evidence regarding TNF-alpha production by cells that are not derived from bone marrow. TNF-alpha production by normal and inflamed human liver was assessed at both mRNA and protein levels. Using a wide panel of novel anti-TNF-alpha monoclonal antibodies and a specific polyclonal antiserum, TNF-alpha immunoreactivity was found in hepatocytes from patients chronically infected with either hepatitis B virus (HBV) or hepatitis C virus. Minimal TNF-alpha immunoreactivity was detected in the mononuclear cell infiltrate and Kupffer cells. In situ hybridization experiments using a TNF-alpha RNA probe showed a significant expression of TNF-alpha mRNA in hepatocytes, Kupffer cells, and some infiltrating mononuclear cells. By contrast, TNF-alpha was detected at low levels in liver biopsies from normal individuals or patients with alcoholic liver disease and low expression of TNF-alpha mRNA was observed in these specimens. Transfection of HepG2 hepatoblastoma cells with either HBV genome or HBV X gene resulted in induction of TNF-alpha expression. Our results demonstrate that viral infection induces, both in vivo and in vitro, TNF-alpha production in hepatocytes, and indicate that the HBV X protein may regulate the expression of this cytokine. These findings suggest that TNF-alpha may have an important role in human liver diseases induced by viruses.

scholarly journals Selective inhibition of spontaneous IgE and IgG4 production by interleukin-8 in atopic patients

Blood ◽  
1995 ◽  
Vol 85 (11) ◽  
pp. 3191-3198 ◽  
Author(s):  
H Kimata ◽  
I Lindley ◽  
K Furusho
Keyword(s):  
Monoclonal Antibody ◽  
B Cells ◽  
Tumor Necrosis ◽  
Selective Inhibition ◽  
Tnf Alpha ◽  
Necrosis Factor Alpha ◽  
Endogenous Production ◽  
Alpha Production ◽  
Factor Alpha ◽  
Necrosis Factor

The effects of interleukin (IL)-8 on spontaneous IgE and IgG4 production in atopic patients were studied. IL-8 inhibited IgE and IgG4 production by purified surface (s) IgE+ and sIgG4+ B cells, respectively, while it had no effect on IgG1, IgG2, IgG3, IgM, IgA1, and IgA2 production by corresponding sIg+ B cells. The IL-8-induced inhibition was counteracted by IL-6 and tumor necrosis factor-alpha (TNF-alpha) and was blocked by anti-IL-8 monoclonal antibody (MoAb). Conversely, the addition of anti-IL-6 MoAb and anti-TNF-alpha MoAb, in the absence of IL-8, inhibited IgE and IgG4 production by sIgE+ and sIgG4+ B cells, respectively. Purified sIgE+ and sIgG4+ B cells expressed IL-6 receptors (R), TNF-alpha R, and IL-8R, and they produced IL-6 and TNF-alpha, but not IL-8. IL-8 had no effect on IL-6R or TNF- alpha R, while it abrogated IL-6 and TNF-alpha production in these cells. In contrast, slgG1+, slgG2+, slgG2+, slgG3+, slgM+, slgA1+, and slgA2+ B cells expressed IL-6R and TNF-alpha R but not IL-8R, and they produced IL-6 and TNF-alpha. IL-8 had no effect on IL-6R and TNF-alpha R, or on TNF-alpha and IL-6 production in these cells. These results indicate that IL-8 inhibits spontaneous IgE and IgG4 production in slgE+ and slgG4+ B cells, respectively, by inhibiting the endogenous production of IL-6 and TNF-alpha.

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