scholarly journals Depletion of Complement Enhances the Clearance of Brucella abortus in Mice

2018 ◽  
Vol 86 (10) ◽  
Author(s):  
Gabriela González-Espinoza ◽  
Elías Barquero-Calvo ◽  
Esteban Lizano-González ◽  
Alejandro Alfaro-Alarcón ◽  
Berny Arias-Gómez ◽  
...  
Keyword(s):  
Immune System ◽  
Brucella Abortus ◽  
Innate Immune ◽  
Control Group ◽  
Bacterial Disease ◽  
Necrosis Factor Alpha ◽  
Content Type ◽  
Factor Alpha ◽  
Necrosis Factor

ABSTRACT Brucellosis is a bacterial disease of animals and humans. Brucella abortus barely activates the innate immune system at the onset of infection, and this bacterium is resistant to the microbicidal action of complement. Since complement stands as the first line of defense during bacterial invasions, we explored the role of complement in B. abortus infections. Brucella abortus-infected mice depleted of complement with cobra venom factor (CVF) showed the same survival rate as mice in the control group. The complement-depleted mice readily eliminated B. abortus from the spleen and did so more efficiently than the infected controls after 7 days of infection. The levels of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-6 (IL-6) remained within background levels in complement-depleted B. abortus-infected mice. In contrast, the levels of the immune activator cytokine gamma interferon and the regulatory cytokine IL-10 were significantly increased. No significant histopathological changes in the liver and spleen were observed between the complement-depleted B. abortus-infected mice and the corresponding controls. The action exerted by Brucella on the immune system in the absence of complement may correspond to a broader phenomenon that involves several components of innate immunity.

scholarly journals Brucella abortus Invasion of Osteocytes Modulates Connexin 43 and Integrin Expression and Induces Osteoclastogenesis via Receptor Activator of NF-κB Ligand and Tumor Necrosis Factor Alpha Secretion

2015 ◽  
Vol 84 (1) ◽  
pp. 11-20 ◽  
Author(s):  
Ayelén Ivana Pesce Viglietti ◽  
Paula Constanza Arriola Benitez ◽  
María Virginia Gentilini ◽  
Lis Noelia Velásquez ◽  
Carlos Alberto Fossati ◽  
...  
Keyword(s):  
Tumor Necrosis Factor ◽  
Brucella Abortus ◽  
Connexin 43 ◽  
Tumor Necrosis ◽  
Necrosis Factor Alpha ◽  
Content Type ◽  
Tnf Α ◽  
Receptor Activator ◽  
Factor Alpha ◽  
Necrosis Factor

Osteoarticular brucellosis is the most common localization of human active disease. Osteocytes are the most abundant cells of bone. They secrete factors that regulate the differentiation of both osteoblasts and osteoclasts during bone remodeling. The aim of this study is to determine ifBrucella abortusinfection modifies osteocyte function. Our results indicate thatB. abortusinfection induced matrix metalloproteinase 2 (MMP-2), receptor activator for NF-κB ligand (RANKL), proinflammatory cytokines, and keratinocyte chemoattractant (KC) secretion by osteocytes. In addition, supernatants fromB. abortus-infected osteocytes induced bone marrow-derived monocytes (BMM) to undergo osteoclastogenesis. Using neutralizing antibodies against tumor necrosis factor alpha (TNF-α) or osteoprotegerin (OPG), RANKL's decoy receptor, we determined that TNF-α and RANKL are involved in osteoclastogenesis induced by supernatants fromB. abortus-infected osteocytes. Connexin 43 (Cx43) and the integrins E11/gp38, integrin-α, integrin-β, and CD44 are involved in cell-cell interactions necessary for osteocyte survival.B. abortusinfection inhibited the expression of Cx43 but did not modify the expression of integrins. Yet the expression of both Cx43 and integrins was inhibited by supernatants fromB. abortus-infected macrophages.B. abortusinfection was not capable of inducing osteocyte apoptosis. However, supernatants fromB. abortus-infected macrophages induced osteocyte apoptosis in a dose-dependent manner. Taken together, our results indicate thatB. abortusinfection could alter osteocyte function, contributing to bone damage.

scholarly journals Role of inflammation and iron exchange disorders in progression of liver cirrosis

2021 ◽  
Vol 38 (1) ◽  
pp. 38-45
Author(s):  
I. A. Bulatova ◽  
A. P. Shchekotova ◽  
S. V. Paducheva
Keyword(s):  
Tumor Necrosis Factor ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Clinical Manifestations ◽  
Control Group ◽  
Necrosis Factor Alpha ◽  
Inflammatory Protein ◽  
Factor Alpha ◽  
Necrosis Factor

Objective. To assess the role of the main pathogenetically significant molecules, including tumor necrosis factor alpha (TNF-) and transferrin, as an inflammatory protein, in the progression of chronic diffuse liver diseases (CDLD). Material and methods. The study involved 86 patients with cirrhosis of the liver (LC) of viral, alcoholic and mixed etiology. Inflammatory parameters were studied, including tumor necrosis factor alpha (TNF-), indicators of iron metabolism, -fetoprotein (AFP), vasculoendothelial growth factor (VEGF), and functional liver biochemical tests. The control group consisted of 70 persons. Results. It was revealed that the LC severity class is interrelated with the clinical manifestations of the disease, the severity of biochemical syndromes as well as a significant increase in the concentration of -globulins, CRP, the amount of TNF- up to 3.5 (2.64.7) pg/ ml (p 0.001) and ferritin up to 325.8 (209; 401) ng / ml (p 0.001) compared to the control group. An increase in TNF- and ferritin as inflammatory protein in LC confirms the growth of the activity of inflammation in the liver and correlates with other parameters involved in the pathogenesis of LC: with VEGF, as a marker of endothelial dysfunction, which is involved in the activation of fibrosis and neoangiogenesis, and AFP, reflecting regeneration processes in the liver. Conclusions. The progression of liver damage in cirrhosis is based primarily on the secondary inflammation caused by portal hypertension with the entry of intestinal antigens and toxins into the central bloodstream. At the same time, the perverse circle of the development of the disease is closed.

scholarly journals Role of Bacillus anthracis Spore Structures in Macrophage Cytokine Responses

2007 ◽  
Vol 75 (5) ◽  
pp. 2351-2358 ◽  
Author(s):  
Subhendu Basu ◽  
Tae Jin Kang ◽  
Wilbur H. Chen ◽  
Matthew J. Fenton ◽  
Les Baillie ◽  
...  
Keyword(s):  
Bacillus Anthracis ◽  
Cytokine Response ◽  
Innate Immune ◽  
Enzyme Linked Immunosorbent Assay ◽  
Toll Like Receptor ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
Macrophage Cytokine ◽  
Necrosis Factor

ABSTRACT The innate immune response of macrophages (Mφ) to spores, the environmentally acquired form of Bacillus anthracis, is poorly characterized. We therefore examined the early Mφ cytokine response to B. anthracis spores, before germination. Mφ were exposed to bacilli and spores of Sterne strain 34F2 and its congenic nongerminating mutant (ΔgerH), and cytokine expression was measured by real-time PCR and an enzyme-linked immunosorbent assay. The exosporium spore layer was retained (exo+) or removed by sonication (exo−). Spores consistently induced a strong cytokine response, with the exo− spores eliciting a two- to threefold-higher response than exo+ spores. The threshold for interleukin-1β (IL-1β) production by wild-type Mφ was significantly lower than that required for tumor necrosis factor alpha expression. Cytokine production was largely dependent on MyD88, suggesting Toll-like receptor involvement; however, the expression of beta interferon in MyD88−/− Mφ suggests involvement of a MyD88-independent pathway. We conclude that (i) the B. anthracis spore is not immunologically inert, (ii) the exosporium masks epitopes recognized by the Mφ, (iii) the Mφ cytokine response to B. anthracis involves multiple pattern recognition receptors and signaling pathways, and (iv) compared to other cytokines, IL-1β is expressed at a lower spore concentration.

Leukogram and cortisol parameters in Swiss mice experimentally infected with Angiostrongylus costaricensis

2021 ◽  
Vol 95 ◽  
Author(s):  
E. Benvegnú ◽  
C.C. Hermes ◽  
J.A. Guizzo ◽  
S.M. Soares ◽  
M.M. Costa ◽  
...  
Keyword(s):  
Cytokine Profile ◽  
Control Group ◽  
Necrosis Factor Alpha ◽  
Swiss Mice ◽  
Hypochromic Anaemia ◽  
Third Stage ◽  
Factor Alpha ◽  
Cortisol Levels ◽  
Necrosis Factor

Abstract This study describes changes in haematological parameters, cytokine profile, histopathology and cortisol levels in Swiss mice experimentally infected with Angiostrongylus costaricensis. Twenty-eight Swiss mice were divided into two groups (G1 and G2) of 14 animals each. In each group, eight animals were infected orally with ten third-stage larvae of A. costaricensis and six were used as a control group. The mice of groups G1 and G2 were sacrificed 14 and 24 days after infection, respectively. Samples were collected for histopathological and haematological analyses and determination of the cytokine profile and cortisol levels. Granulomatous reaction, eosinophilic infiltrate and vasculitis in the intestinal tract, pancreas, liver and spleen were observed with varying intensity in infected animals. Our results showed that the mice developed normocytic and hypochromic anaemia, and that the histopathological lesions caused by the experimental infection influenced increases in cortisol, neutrophil and monocyte levels. In addition to this, we detected increased interleukin-6 and tumour necrosis factor alpha levels in the infected animals.

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