scholarly journals Increased Mortality and Dysregulated Cytokine Production in Tumor Necrosis Factor Receptor 1-Deficient Mice following Systemic Klebsiella pneumoniae Infection

2003 ◽  
Vol 71 (9) ◽  
pp. 4891-4900 ◽  
Author(s):  
Thomas A. Moore ◽  
Michelle L. Perry ◽  
Andrew G. Getsoian ◽  
Christine L. Monteleon ◽  
Anna L. Cogen ◽  
...  

ABSTRACT A significant clinical complication of pulmonary infections with Klebsiella pneumoniae is peripheral blood dissemination, resulting in a systemic infection concurrent with the localized pulmonary infection. In this context, little is known about the role of tumor necrosis factor receptor 1 (TNFR1)-mediated innate immune responses during systemic Klebsiella infections. Mice lacking TNFR1 were significantly more susceptible to Klebsiella-induced mortality following intravenous inoculation. Bacterial clearance was impaired in TNFR1-deficient mice at early times following infection. Unexpectedly, bacterial burdens at the onset of mortality (days 2 to 3 postinfection) were not higher in mice lacking TNFR1. However, elevated production of liver-associated proinflammatory cytokines (interleukin-12, tumor necrosis factor alpha [TNF-α[, and gamma interferon [IFN-γ]) and chemokines (MIP-1α, MIP-2, and MCP-1) was observed within the first 24 h of infection. Additionally, excessive plasma-associated IFN-γ was also observed late in the course of infection (day 3). Spleen cells from day-3 infected TNFR1-deficient mice secreted markedly enhanced levels of IFN-γ when cultured in vitro. Additionally, there was a marked increase in the total number of activated lymphocyte subsets as indicated by CD69 upregulation. A notable exception was the sharp decrease in the frequency of splenic NK T cells in infected TNFR1 knockout (KO) mice. Anti-TNF-α therapy in TNFR1 KO mice significantly reduced chemokine production and liver injury. Combined, these data indicate a dysregulated antibacterial host response following intravenous Klebsiella infection in the absence of TNFR1 signaling, resulting in heightened cytokine production and hyperactivation of specific splenic lymphocyte subsets.

2003 ◽  
Vol 10 (1) ◽  
pp. 44-52 ◽  
Author(s):  
John A. Christopherson ◽  
Erik L. Munson ◽  
Douglas M. England ◽  
Cindy L. Croke ◽  
Monica C. Remington ◽  
...  

ABSTRACT We found that Borrelia burgdorferi-vaccinated gamma interferon-deficient (IFN-γ0) mice challenged with B. burgdorferi developed prominent chronic destructive osteoarthropathy. When these mice were treated with anti-tumor necrosis factor alpha (TNF-α) antibody, the severity of the destructive osteoarthritis was enhanced and affected the mobility of the animals. In addition, extensive swelling of the hind paws occurred. In contrast, treatment of B. burgdorferi-vaccinated, challenged IFN-γ0 mice with recombinant TNF-α (rTNF-α) inhibited the development of arthritis, including swelling of the hind paws. Moreover, treatment of vaccinated, challenged IFN-γ0 mice with anti-TNF-α inhibited fourfold the production of an antibody that kills B. burgdorferi, while treatment of vaccinated, challenged IFN-γ0 mice with rTNF-α slightly elevated the level of the borreliacidal antibody. These results suggest that the level of TNF-α directly or indirectly regulates the production of borreliacidal antibody and the development of vaccine-induced destructive Lyme osteoarthritis. Studies are in progress to determine the mechanism by which TNF-α-dependent cytokines generate the destructive arthritis.


1999 ◽  
Vol 189 (7) ◽  
pp. 1083-1092 ◽  
Author(s):  
George S. Yap ◽  
Alan Sher

Although interferon (IFN)-γ–activated, mononuclear phagocytes are considered to be the major effectors of resistance to intracellular pathogens, it is unclear how they control the growth of microorganisms that reside in nonhemopoietic cells. Pathogens within such cells may be killed by metabolites secreted by activated macrophages or, alternatively, directly controlled by cytokine-induced microbicidal mechanisms triggered within infected nonphagocytic cells. To distinguish between these two basic mechanisms of cell-mediated immunity, reciprocal bone marrow chimeras were constructed between wild-type and IFN-γ receptor–deficient mice and their survival assessed following infection with Toxoplasma gondii, a protozoan parasite that invades both hemopoietic and nonhemopoietic cell lineages. Resistance to acute and persistent infection was displayed only by animals in which IFN-γ receptors were expressed in both cellular compartments. Parallel chimera experiments performed with tumor necrosis factor (TNF) receptor–deficient mice also indicated a codependence on hemopoietic and nonhemopoietic lineages for optimal control of the parasite. In contrast, in mice chimeric for inducible nitric oxide synthase (iNOS), an enzyme associated with IFN-γ–induced macrophage microbicidal activity, expression by cells of hemopoietic origin was sufficient for host resistance. Together, these findings suggest that, in concert with bone marrow–derived effectors, nonhemopoietic cells can directly mediate, in the absence of endogenous iNOS, IFN-γ– and TNF-α–dependent host resistance to intracellular infection.


2008 ◽  
Vol 87 (6) ◽  
pp. 558-563 ◽  
Author(s):  
P. Palmqvist ◽  
P. Lundberg ◽  
I. Lundgren ◽  
L. Hänström ◽  
U.H. Lerner

Interleukin-6 (IL-6)-type cytokines are pleiotropic molecules capable of stimulating bone resorption and expressed by numerous cell types. In the present study, we tested the hypothesis that gingival fibroblasts may exert local osteotropic effects through production of IL-6 and related cytokines. IL-6-type cytokine expression and regulation by IL-1β and tumor necrosis factor-α (TNF-α) were studied in fibroblasts from the non-inflamed gingiva of healthy individuals. Constitutive mRNA expression of IL-6, IL-11, and leukemia inhibitory factor (LIF), but not of oncostatin M (OSM), was demonstrated, as was concentration-dependent stimulation of IL-6 and LIF mRNA and of protein by IL-1β and TNF-α. IL-11 mRNA and protein were concentration-dependently stimulated by IL-1β. The signaling pathway involved in IL-6 and LIF mRNA stimulation involved MAP kinases, but not NF-κB. The findings support the view that resident cells may influence the pathogenesis of periodontal disease through osteotropic IL-6-type cytokine production mediated by activation of MAP kinases. Abbreviations: IL-1α (interleukin-1α); IL-1β (interleukin-1β); IL-6 (interleukin-6); IL-11 (interleukin-11); LIF (leukemia inhibitory factor); OSM (oncostatin M); α(1)-coll. I (α(1)-collagen I); ALP (alkaline phosphatase); BMP-2 (bone morphogenetic protein-2); OC (osteocalcin); BSP (bone sialoprotein); TNFR I (tumor necrosis factor receptor I); TNFR II (tumor necrosis factor receptor II); IL-1R1 (interleukin-1 receptor 1); GAPDH (glyceraldehyde-3-phosphate dehydrogenase); RPL13A (ribosomal protein L13A); mRNA (messenger ribonucleic acid); cDNA (complementary deoxyribonucleic acid); PCR (polymerase chain-reaction); BCA (bicinchoninic acid); ELISA (enzyme-linked immunosorbent assay); α-MEM (α modification of Minimum Essential Medium); and FCS (fetal calf serum).


2001 ◽  
Vol 69 (5) ◽  
pp. 2847-2852 ◽  
Author(s):  
Julia Y. Lee ◽  
Kathleen E. Sullivan

ABSTRACT Lipopolysaccharide (LPS) is a very potent inducer of tumor necrosis factor alpha (TNF-α) expression from monocytes and macrophages. Another inflammatory cytokine, gamma interferon (IFN-γ), can potentiate the effects of LPS, but the mechanism is not thoroughly understood. Previous reports emphasized the ability of IFN-γ to upregulate CD14 expression (the receptor for LPS), and nearly all studies have utilized sequential stimulation with IFN-γ followed by LPS to exploit this phenomenon. This study demonstrates that IFN-γ can upregulate the effect of LPS at the level of transcription. Human monoblastic Mono-Mac-6 cells produced up to threefold-greater levels of TNF-α when simultaneously stimulated with LPS and IFN-γ compared to treatment with LPS alone. RNase protection studies showed a similar increase in RNA beginning as early as within 30 min. The synthesis of TNF-α mRNA in IFN-γ- and LPS-treated Mono-Mac-6 cells was also temporally prolonged even though the message turnover rate was identical to that seen in LPS stimulated cells. The modulatory effect of IFN-γ may be mediated by Jak2.


2000 ◽  
Vol 68 (9) ◽  
pp. 5234-5240 ◽  
Author(s):  
Catherine Newton ◽  
Shannon McHugh ◽  
Ray Widen ◽  
Noriya Nakachi ◽  
Thomas Klein ◽  
...  

ABSTRACT Infection of BALB/c mice with a sublethal concentration ofLegionella pneumophila causes an acute disease that is resolved by innate immune responses. The infection also initiates the development of adaptive Th1 responses that protect the mice from challenge infections. To study the early responses, cytokines induced during the first 24 h after infection were examined. In the serum, interleukin-12 (IL-12) was detectable by 3 h and peaked at 10 h, while gamma interferon was discernible by 5 h and peaked at 8 h. Similar patterns were observed in ex vivo cultures of splenocytes. A transient IL-4 response was also detected by 3 h postinfection in ex vivo cultures. BALB/c IL-4-deficient mice were more susceptible to L. pneumophila infection than were wild-type mice. The infection induced higher serum levels of acute-phase cytokines (tumor necrosis factor alpha [TNF-α], IL-1β, and IL-6), and reducing TNF-α levels with antibodies protected the mice from death. Moreover, the addition of IL-4 to L. pneumophila-infected macrophage cultures suppressed the production of these cytokines. Thus, the lack of IL-4 in the deficient mice resulted in unchecked TNF-α production, which appeared to cause the mortality. Monocyte chemoattractant protein-1 (MCP-1), a chemokine that is induced by IL-4 during Listeria monocytogenesinfection, was detected at between 2 and 30 h after infection. However, MCP-1 did not appear to be induced by IL-4 or to be required for the TNF-α regulation by IL-4. The data suggest that the early increase in IL-4 serves to regulate the mobilization of acute phase cytokines and thus controls the potential harmful effects of these cytokines.


2007 ◽  
Vol 86 (11) ◽  
pp. 1089-1094 ◽  
Author(s):  
I. Andrade ◽  
T.A. Silva ◽  
G.A.B. Silva ◽  
A.L. Teixeira ◽  
M.M. Teixeira

Orthodontic tooth movement is dependent on osteoclast activity. Tumor necrosis factor (TNF)-α plays an important role, directly or via chemokine release, in osteoclast recruitment and activation. This study aimed to investigate whether the TNF receptor type 1 (p55) influences these events and, consequently, orthodontic tooth movement. An orthodontic appliance was placed in wild-type mice (WT) and p55-deficient mice (p55−/−). Levels of TNF-α and 2 chemokines (MCP-1/CCL2, RANTES/CCL5) were evaluated in periodontal tissues. A significant increase in CCL2 and TNF-α was observed in both groups after 12 hrs of mechanical loading. However, CCL5 levels remained unchanged in p55−/− mice at this time-point. The number of TRAP-positive osteoclasts in p55−/− mice was significantly lower than that in WT mice. Also, there was a significantly smaller rate of tooth movement in p55−/− mice. Analysis of our data suggests that the TNFR-1 plays a significant role in orthodontic tooth movement that might be associated with changes in CCL5 levels.


2005 ◽  
Vol 73 (2) ◽  
pp. 849-858 ◽  
Author(s):  
Simone Korten ◽  
Richard J. Anderson ◽  
Carolyn M. Hannan ◽  
Eric G. Sheu ◽  
Robert Sinden ◽  
...  

ABSTRACT Understanding the protective mechanism in the liver induced by recombinant vaccines against the pre-erythrocytic stages of malaria is important for vaccine development. Most studies in mice have focused on splenic and peripheral blood T cells and identified gamma interferon (IFN-γ)-producing CD8+ T cells as correlates of protection, which can be induced by prime-boost vaccination with recombinant poxviruses. Invariant natural killer T (Vα14iNKT) cells can also protect against liver stage malaria, when activated, and are abundant in the liver. Since poxviruses have nonspecific immunomodulating effects, which are incompletely understood, we investigated whether recombinant poxviruses affect the protective properties of hepatic Vα14iNKT cells and thus vaccine efficacy. We show that intradermal vaccination with recombinant poxviruses activated Vα14iNKT cells and NK cells in the livers of BALB/c mice while inducing IFN-γ- and tumor necrosis factor alpha (TNF-α)-producing pre-erythrocytic stage antigen-specific CD8+ T cells. Greater numbers of hepatic Vα14iNKT cells secreted interleukin-4 than IFN-γ. Vaccinated Vα14iNKT-cell-deficient mice had lower, but still protective levels of hepatic and splenic IFN-γ+ and TNF-α+ CD8+ T cells and better protection rates later after challenge with Plasmodium berghei sporozoites. Therefore, vaccine-activated hepatic Vα14iNKT cells help in generating specific T cells but are not required for protection induced by recombinant poxviruses. Furthermore, double-positive INF-γ+/TNF-α+ CD8+ T cells were enriched in protected livers, suggesting that cells expressing both of these cytokines may be most relevant for protection.


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