scholarly journals Differential Tumor Necrosis Factor Alpha Expression and Release from Peritoneal Mouse Macrophages In Vitro in Response to Proliferating Gram-Positive versus Gram-Negative Bacteria

2000 ◽  
Vol 68 (8) ◽  
pp. 4422-4429 ◽  
Author(s):  
Wei Cui ◽  
David C. Morrison ◽  
Richard Silverstein

ABSTRACT Viable Escherichia coli and Staphylococcus aureus bacteria elicited markedly different in vitro tumor necrosis factor alpha (TNF-α) responses when placed in coculture with peritoneal murine macrophages. These include quantitative differences in TNF-α mRNA expression and corresponding protein product secretion as well as kinetic differences in the profiles of the TNF-α responses. Further, lipopolysaccharide (from E. coli) is a major contributing factor to these differences, as revealed by comparative experiments with endotoxin-responsive (C3Heb/FeJ) and endotoxin-hyporesponsive (C3H/HeJ) macrophages. Nevertheless, the eventual overall magnitude of the TNF-α secretion of macrophages in response to S. aureus was at least equivalent to that observed with E. coli, while appearing at time periods hours later than the E. coli-elicited TNF-α response. Both the magnitude and kinetic profile of the TNF-α responses were found to be relatively independent of the rate of bacterial proliferation, at least to the extent that similar results were observed with both viable and paraformaldehyde-killed microbes. Nevertheless, S. aureus treated in culture with the carbapenem antibiotic imipenem manifests markedly altered profiles of TNF-α response, with the appearance of an early TNF-α peak not seen with viable organisms, a finding strikingly similar to that recently reported by our laboratory from in vivo studies (R. Silverstein, J. G. Wood, Q. Xue, M. Norimatsu, D. L. Horn, and D. C. Morrison, Infect. Immun. 68:2301–2308, 2000). In contrast, imipenem treatment of E. coli-cocultured macrophages does not significantly alter the observed TNF-α response either in vitro or in vivo. In conclusion, our data support the concept that the host inflammatory response of cultured mouse macrophages in response to viable gram-positive versus gram-negative microbes exhibits distinctive characteristics and that these distinctions are, under some conditions, altered on subsequent bacterial killing, depending on the mode of killing. Of potential importance, these distinctive in vitro TNF-α profiles faithfully reflect circulating levels of TNF-α in infected mice. These results suggest that coculture of peritoneal macrophages with viable versus antibiotic-killed bacteria and subsequent assessment of cytokine response (TNF-α) may be of value in clarifying, and ultimately controlling, related host inflammatory responses in septic patients.

2002 ◽  
Vol 70 (12) ◽  
pp. 6628-6637 ◽  
Author(s):  
Christopher J. Papasian ◽  
Richard Silverstein ◽  
Jian Jun Gao ◽  
David M. Bamberger ◽  
David C. Morrison

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.


2001 ◽  
Vol 21 (15) ◽  
pp. 4856-4867 ◽  
Author(s):  
Okot Nyormoi ◽  
Zhi Wang ◽  
Dao Doan ◽  
Maribelis Ruiz ◽  
David McConkey ◽  
...  

ABSTRACT Several reports have linked activating protein 2α (AP-2α) to apoptosis, leading us to hypothesize that AP-2α is a substrate for caspases. We tested this hypothesis by examining the effects of tumor necrosis factor alpha (TNF-α) on the expression of AP-2 in breast cancer cells. Here, we provide evidence that TNF-α downregulates AP-2α and AP-2γ expression posttranscriptionally during TNF-α-induced apoptosis. Both a general caspase antagonist (zVADfmk) and a caspase 6-preferred antagonist (zVEIDfmk) inhibited TNF-α-induced apoptosis and AP-2α downregulation. In vivo tests showed that AP-2α was cleaved by caspases ahead of the DNA fragmentation phase of apoptosis. Recombinant caspase 6 cleaved AP-2α preferentially, although caspases 1 and 3 also cleaved it, albeit at 50-fold or higher concentrations. Activated caspase 6 was detected in TNF-α-treated cells, thus confirming its involvement in AP-2α cleavage. All three caspases cleaved AP-2α at asp19 of the sequence asp-arg-his-asp (DRHD19). Mutating D19 to A19abrogated AP-2α cleavage by all three caspases. TNF-α-induced cleavage of AP-2α in vivo led to AP-2α degradation and loss of DNA-binding activity, both of which were prevented by pretreatment with zVEIDfmk. AP-2α degradation but not cleavage was inhibited in vivo by PS-431 (a proteasome antagonist), suggesting that AP-2α is degraded subsequent to cleavage by caspase 6 or caspase 6-like enzymes. Cells transfected with green fluorescent protein-tagged mutant AP-2α are resistant to TNF-α-induced apoptosis, further demonstrating the link between caspase-mediated cleavage of AP-2α and apoptosis. This is the first report to demonstrate that degradation of AP-2α is a critical event in TNF-α-induced apoptosis. Since the DRHD sequence in vertebrate AP-2 is widely conserved, its cleavage by caspases may represent an important mechanism for regulating cell survival, proliferation, differentiation, and apoptosis.


2003 ◽  
Vol 12 (6) ◽  
pp. 323-328 ◽  
Author(s):  
Shigeru Abe ◽  
Naho Maruyama ◽  
Kazumi Hayama ◽  
Hiroko Ishibashi ◽  
Shigeharu Inoue ◽  
...  

Background:In aromatherapy, essential oils are used as anti-inflammatory remedies, but experimental studies on their action mechanisms are very limited.Aims:To assess their anti-inflammatory activities, effects of essential oils on neutrophil activation were examinedin vitro.Methods:Neutrophil activation was measured by tumor necrosis factor-alpha (TNF-α)-induced adherence reaction of human peripheral neutrophils.Results:All essential oils tested at 0.1% concentration suppressed TNF-α-induced neutrophil adherence, and, in particular, lemongrass, geranium and spearmint oils clearly lowered the reaction even at 0.0125%. Similar inhibitory activities for the neutrophil adherence were obtained by their major constituent terpenoids: citral, geraniol, citronellol and carvone. In contrast, very popular essential oils, tea tree oil and lavender oil, did not display the inhibitory activity at the concentration.Conclusion:Thus, some essential oils used as anti-inflammatory remedies suppress neutrophil activation by TNF-α at a low concentration (0.0125-0.025%)in vitro.


2001 ◽  
Vol 69 (4) ◽  
pp. 2162-2171 ◽  
Author(s):  
Lisl K. M. Shoda ◽  
Kimberly A. Kegerreis ◽  
Carlos E. Suarez ◽  
Isabel Roditi ◽  
Ricardo S. Corral ◽  
...  

ABSTRACT The activation of innate immune responses by genomic DNA from bacteria and several nonvertebrate organisms represents a novel mechanism of pathogen recognition. We recently demonstrated the CpG-dependent mitogenic activity of DNA from the protozoan parasiteBabesia bovis for bovine B lymphocytes (W. C. Brown, D. M. Estes, S. E. Chantler, K. A. Kegerreis, and C. E. Suarez, Infect. Immun. 66:5423–5432, 1998). However, activation of macrophages by DNA from protozoan parasites has not been demonstrated. The present study was therefore conducted to determine whether DNA from the protozan parasites B. bovis, Trypanosoma cruzi, and T. brucei activates macrophages to secrete inflammatory mediators associated with protective immunity. DNA fromEscherichia coli and all three parasites stimulated B-lymphocyte proliferation and increased macrophage production of interleukin-12 (IL-12), tumor necrosis factor alpha (TNF-α), and nitric oxide (NO). Regulation of IL-12 and NO production occurred at the level of transcription. The amounts of IL-12, TNF-α, and NO induced by E. coli and protozoal DNA were strongly correlated (r 2 > 0.9) with the frequency of CG dinucleotides in the genome, and immunostimulation by DNA occurred in the order E. coli ≥ T. cruzi > T. brucei > B. bovis. Induction of inflammatory mediators by E. coli, T. brucei, and B. bovis DNA was dependent on the presence of unmethylated CpG dinucleotides. However, at high concentrations,E. coli and T. cruzi DNA-mediated macrophage activation was not inhibited following methylation. The recognition of protozoal DNA by B lymphocytes and macrophages may provide an important innate defense mechanism to control parasite replication and promote persistent infection.


Blood ◽  
2000 ◽  
Vol 96 (10) ◽  
pp. 3585-3591 ◽  
Author(s):  
Keith E. Norman ◽  
Andreas G. Katopodis ◽  
Gebhard Thoma ◽  
Frank Kolbinger ◽  
Anne E. Hicks ◽  
...  

Abstract Selectin-dependent rolling is the earliest observable event in the recruitment of leukocytes to inflamed tissues. Several glycoproteins decorated with sialic acid, fucose, and/or sulfate have been shown to bind the selectins. The best-characterized selectin ligand is P-selectin glycoprotein-1 (PSGL-1) that supports P-selectin– dependent rolling in vitro and in vivo. In vitro studies have suggested that PSGL-1 may also be a ligand for E- and L-selectins. To study the in vivo function of PSGL-1, without the influence of other leukocyte proteins, the authors observed the interaction of PSGL-1–coated microspheres in mouse venules stimulated to express P- and/or E-selectin. Microspheres coated with functional recombinant PSGL-1 rolled in surgically stimulated and tumor necrosis factor alpha (TNFα)-stimulated mouse venules. P-selectin deficiency or inhibition abolished microsphere rolling in surgically and TNFα-stimulated venules, whereas E-selectin deficiency or inhibition increased microsphere rolling velocity in TNFα-stimulated venules. The results suggest that P-selectin–PSGL-1 interaction alone is sufficient to mediate rolling in vivo and that E-selectin–PSGL-1 interaction supports slow rolling.


2006 ◽  
Vol 24 (13) ◽  
pp. 2105-2112 ◽  
Author(s):  
Sandra J. Strauss ◽  
Lenushka Maharaj ◽  
Susan Hoare ◽  
Peter W. Johnson ◽  
John A. Radford ◽  
...  

Purpose To determine the efficacy of bortezomib in patients with lymphoid malignancy, correlating clinical response with effect on plasma cytokines and in vitro activity in primary cultures. Patients and Methods Patients received bortezomib (1.3 mg/m2) on days 1, 4, 8, and 11 of a 3-week cycle. Plasma tumor necrosis factor alpha (TNF-α) and interleukin-6 were measured before each treatment, and bortezomib activity was examined in patient samples grown in primary culture. Results Fifty-one patients received a total of 193 cycles of treatment. Twenty-four patients had mantle cell lymphoma (MCL), 13 had follicular lymphoma (FL), six had lymphoplasmacytic lymphoma, six had Hodgkin's disease (HD), and one each had diffuse large B-cell lymphoma and adult T-cell leukemia/lymphoma. Patients were heavily pretreated with a median of four previous therapies. Significant grade 3 to 4 toxicities were thrombocytopenia (n = 22), fatigue (n = 10), and peripheral neuropathy (n = 3). Seven patients with MCL responded to treatment (one complete response, six partial responses [PRs]; overall response rate, 29%). Two patients with FL achieved a late PR 3 months after discontinuing therapy. Two patients with Waldenström's macroglobulinemia and one patient with HD achieved a PR. MCL primary cultures demonstrated greater sensitivity to bortezomib than FL (median 50% effective concentration for viability, 209 nmol/L v 1,311 nmol/L, respectively; P = .07), which correlated with clinical response. A median reduction in plasma TNF-α of 98% was observed in six patients with MCL who responded to bortezomib compared with a reduction of 38% in six nonresponders (P = .07). Conclusion Bortezomib demonstrates encouraging efficacy in MCL in heavily pretreated individuals. Response was associated with a reduction in plasma TNF-α and in vitro sensitivity in a small number of patients.


2003 ◽  
Vol 10 (5) ◽  
pp. 960-966 ◽  
Author(s):  
W. R. Waters ◽  
M. V. Palmer ◽  
D. L. Whipple ◽  
M. P. Carlson ◽  
B. J. Nonnecke

ABSTRACT Bovine tuberculosis in the United States has proven costly to cattle producers as well as to government regulatory agencies. While in vivo responsiveness to mycobacterial antigens is the current standard for the diagnosis of tuberculosis, in vitro assays are gaining acceptance, especially as ancillary or complementary tests. To evaluate in vitro indices of cellular sensitization, antigen-induced gamma interferon (IFN-γ), nitric oxide (NO), and tumor necrosis factor alpha (TNF-α) responses by blood mononuclear cells from Mycobacterium bovis-infected cattle were quantified and compared. Using an aerosol model of infection, two doses of each of two strains of M. bovis (95-1315 and HC-2045T) were used to induce a range of IFN-γ, NO, and TNF-α responses. Infection-specific increases in NO, but not in IFN-γ or TNF-α, were detected in nonstimulated cultures at 48 h, a finding that is indicative of nonspecific activation and spontaneous release of NO. The infective dose of M. bovis organisms also influenced responses. At 34 days postinfection, IFN-γ, NO, and TNF-α responses in antigen-stimulated cells from cattle receiving 105 CFU of M. bovis organisms were greater than responses of cells from cattle infected with 103 CFU of M. bovis organisms. The NO response, but not the IFN-γ and TNF-α responses, was influenced by infective strains of M. bovis. The TNF-α, NO, and IFN-γ responses followed similar kinetics, with strong positive associations among the three readouts. Overall, these findings indicate that NO and TNF-α, like IFN-γ, may prove useful as indices for the diagnosis of bovine tuberculosis.


Blood ◽  
1994 ◽  
Vol 83 (5) ◽  
pp. 1216-1225 ◽  
Author(s):  
F Rosselli ◽  
J Sanceau ◽  
E Gluckman ◽  
J Wietzerbin ◽  
E Moustacchi

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.


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