Search results for "Cytokines"
showing 10 items of 845 documents
Skin-derived macrophages from Leishmania major-susceptible mice exhibit interleukin-12- and interferon-gamma-independent nitric oxide production and …
2002
Co-administration of CpG-containing immunostimulatory oligodeoxynucleotides and parasite antigen protects susceptible BALB/c mice from otherwise progressive infection with Leishmania major. Although the protective effect of CpG-containing immunostimulatory oligodeoxynucleotides is clearly dependent on endogenous interleukin-12 and interferon-gamma production, the source of these Th1-promoting cytokines in infected mice is unknown. In contrast to macrophages from Leishmania-resistant C57BL/6 mice, macrophages from susceptible BALB/c mice are hyporesponsive to stimulation with lipopolysaccharide and interferon-gamma. While studying interactions of various antigen-presenting cells with Leishma…
Lipoic acid lessens Th1-mediated inflammation in lipopolysaccharide-induced uveitis reducing selectively Th1 lymphocytes-related cytokines release
2013
AbstractInflammation results in the production of free radicals. We evaluated the anti-inflammatory and antioxidant capacity of lipoic acid in an experimental uveitis model upon a subcutaneous injection of endotoxin into Lewis rats. The role of oxidative stress in the endotoxin-induced uveitis model is well-known. Besides, the Th1 response classically performs a central part in the immunopathological process of experimental autoimmune uveitis. Exogenous sources of lipoic acid have been shown to exhibit antioxidant and anti-inflammatory properties. Our results show that lipoic acid treatment plays a preventive role in endotoxin-induced oxidative stress at 24 h post-administration and reduced…
Phase I study of OM-174, a lipid A analogue, with assessment of immunological response, in patients with refractory solid tumors.
2013
International audience; BACKGROUND: Lipids A, the lipophilic partial structure of lipopolysaccharides, induce regression of several tumor types in animal models. Rather than exerting direct cytotoxic effect, these compounds trigger the immune system which in turn stimulates secretion of cytokines, and activates the inducible nitric oxide synthase, as well as immune cell infiltration of tumors. OM-174 is an analogue of lipid A with dual action on toll-like receptors 2 and 4. In an experimental model of peritoneal carcinomatosis induced in BDIX rats by intraperitoneal injection of syngeneic PROb colon cancer cells, it induced a complete regression of tumors. The present phase I trial was cond…
Pivotal advance: alpha-galactosylceramide induces protection against lipopolysaccharide-induced shock.
2007
Abstract α−galactosylceramide, a natural killer T cell ligand, and its synthetic homolog, KRN7000, consistently influence IFN-γ and TNF-α release, both mediators of LPS-induced shock. To modify the course of endotoxin shock, we injected KRN7000 at different time points of experimental systemic Shwartzman reaction. Mice treated with KRN7000 survived when it was injected within 2 h before and after LPS challenge. Mice survival was associated with low levels of T helper 1 (Th1) cytokines, such as IFN-γ and TNF-α. By contrast, protection from endotoxin shock was associated with an increase of T helper 2 (Th2) cytokines, like IL-4 and IL-10. A role of Th2 cytokines in counteracting LPS-induced s…
Nitric oxide synthase activity is inducible in rat, but not rabbit alveolar macrophages, with a concomitant reduction in arginase activity
1995
Alveolar macrophages were obtained by broncho-alveolar lavage of isolated rat and rabbit lungs and cultured (2.5 × 106 cells/dish) for 18 h in the absence or presence of bacterial lipopolysaccharides (LPS) alone or in combination with cytokines. Thereafter, accumulation of 3H-citrulline (NO synthase activity) and 3H-ornithine (arginase activity) were determined. During incubation of rat alveolar macrophages with 3H-arginine clear amounts of 3H-citrulline and 3H-ornithine (3.8 and 4.6% of the added 3H-arginine, respectively) were formed and most of these metabolites appeared in the incubation medium (ratios extra-/intracellular of 17 and 70 for 3H-citrulline and 3H-ornithine, respectively). …
Intravitreal injection of bevacizumab induces inflammatory alterations in a uveitis experimental model.
2010
PurposeBevacizumab is currently used as an intravitreal agent in the treatment of inflammatory-associated eye diseases. The aim of the current study is to explore the effects of the intravitreal injection of bevacizumab on aqueous humour cytokines and chemokines in an experimental uveitis model.MethodsEndotoxin-induced uveitis was induced in rats by footpad injections. Bevacizumab was administered by intravitreal injection (75 μg in 3–μL samples) and different chemokine and cytokine proteins were quantified in aqueous humor.ResultsIntravitreal administration of bevacizumab led to a several-fold increase of RANTES, MCP-1, and IFN-γ concentrations in aqueous humor of endotoxin-treated rats.Co…
New insight into the inhibition of the inflammatory response to experimental delayed-type hypersensitivity reactions in mice by scropolioside A.
2006
Scropolioside A, an iridoid isolated from Scrophularia auriculata ssp. pseudoauriculata, showed anti-inflammatory properties against different experimental models of delayed-type hypersensitivity. This iridoid reduced the oedema induced by oxazolone by 79% (72 h) at 0.5 mg/ear while reducing that induced by sheep red blood cells by 47% (18 h), 45% (24 h) and 36% (48 h) at 10 mg/kg. In vivo it reduced both oedema formation and cell infiltration whereas in vitro it reduced the proliferation of activated T-lymphocytes (IC50 of 67.74 microM). Treatment with scropolioside A (100 microM) 18 and 24 h after phytohemagglutinin stimulation increased the number of cells arrested in the subG(0) phase w…
Regulation of T cells in asthma: implications for genetic manipulation
2004
PURPOSE OF THE REVIEW Allergic asthma is a disease characterized by airway hyperresponsiveness, inflammation and remodeling. In the past few decades it has become clear that the pathogenesis and development of this disease is controlled by cytokines released by CD4 T helper type 2 lymphocytes that develop under the influence of natural killer lymphocytes. At birth, T cell priming exhibits a T helper type 2 bias and the development of the T helper phenotype is determined in the first year of life by environmental exposure to virus or bacterial substances or environmental allergens in genetically predisposed individuals. Decreased exposure to infection in early childhood has thus been linked …
Prophylaxis of lipopolysaccharide-induced shock by α-galactosylceramide
2008
AbstractThe NKT cell ligand α-galactosylceramide and its synthetic homologue KRN7000 stimulate rapid and copious secretion of IFN-γ and TNF-α release, both of which are key mediators of LPS-induced shock. We showed that KRN7000, injected before or within 2 h after LPS challenge, was able to prevent endotoxic shock. KRN7000 induced survival when the mice were injected 6, 9, or 12 days before the first injection of LPS, and this protective effect was associated with reduction upon subsequent challenge in the levels of IFN-γ, TNF-α, MCP-1, and an increase of IL-10. Further analysis showed that the animals treated with KRN7000 prior to LPS challenge had lower numbers of F4/80+, NKT, and NK cell…
Quaking and miR-155 interactions in inflammation and leukemogenesis.
2015
Quaking (QKI) is a tumor-suppressor gene encoding a conserved RNA-binding protein, whose expression is downregulated in several solid tumors. Here we report that QKI plays an important role in the immune response and suppression of leukemogenesis. We show that the expression of Qki is reduced in lipopolysaccharide (LPS)-challenged macrophages, suggesting that Qki is a key regulator of LPS signaling pathway. Furthermore, LPS-induced downregulation of Qki expression is miR-155-dependent. Qki overexpression impairs LPS-induced phosphorylation of JNK and particularly p38 MAPKs, in addition to increasing the production of anti-inflammatory cytokine IL-10. In contrast, Qki ablation decreases Fas …