scholarly journals Absence of interleukin-10 reduces progression of shiga toxin-induced hemolytic uremic syndrome

2021 ◽  
Vol 135 (3) ◽  
pp. 575-588
Author(s):  
Gonzalo Ezequiel Pineda ◽  
Bárbara Rearte ◽  
María Florencia Todero ◽  
Andrea Cecilia Bruballa ◽  
Alan Mauro Bernal ◽  
...  

Abstract Hemolytic Uremic Syndrome (HUS), a disease triggered by Shiga toxin (Stx), is characterized by hemolytic anemia, thrombocytopenia and renal failure. The inflammatory response mediated by polymorphonuclear neutrophils (PMNs) and monocytes is essential to HUS onset. Still, the role of anti-inflammatory cytokines is less clear. The deficiency of IL-10, an anti-inflammatory cytokine, leads to severe pathology in bacterial infections but also to beneficial effects in models of sterile injury. The aim of this work was to analyze the role of IL-10 during HUS. Control and IL-10 lacking mice (IL-10−/−) were intravenously injected with Stx type 2 (Stx2) and survival rate was evaluated. PMN and circulating and renal pro- and anti-inflammatory factors were analyzed by FACS and enzyme-linked immunosorbent assay (ELISA) respectively. IL-10−/− mice showed a higher survival associated with lower renal damage reflected by reduced plasma urea and creatinine levels than control mice. Circulating PMN increased at 72 h in both mouse strains accompanied by an up-regulation of CD11b in control mice. In parallel, renal PMN were significantly increased only in control mice after toxin. Plasma TNF-α, IL-6 and corticosterone levels were higher increased in IL-10−/− than control mice. Simultaneously renal TNF-α raised constantly but was accompanied by increased TGF-β levels in IL-10−/− mice. These results demonstrate that the profile of circulating and renal cytokines after Stx2 differed between strains suggesting that balance of these factors could participate in renal protection. We conclude that IL-10 absence has a protective role in an experimental model of HUS by reducing PMN recruitment into kidney and renal damage, and increasing mice survival.

2010 ◽  
Vol 78 (9) ◽  
pp. 3689-3699 ◽  
Author(s):  
Erin K. Lentz ◽  
Rama P. Cherla ◽  
Valery Jaspers ◽  
Bradley R. Weeks ◽  
Vernon L. Tesh

ABSTRACTMice have been extensively employed as an animal model of renal damage caused by Shiga toxins. In this study, we examined the role of the proinflammatory cytokine tumor necrosis factor alpha (TNF-α) in the development of toxin-mediated renal disease in mice. Mice pretreated with TNF-α and challenged with Shiga toxin type 1 (Stx1) showed increased survival compared to that of mice treated with Stx1 alone. Conversely, mice treated with Stx1 before TNF-α administration succumbed more quickly than mice given Stx1 alone. Increased lethality in mice treated with Stx1 followed by TNF-α was associated with evidence of glomerular damage and the loss of renal function. No differences in renal histopathology were noted between animals treated with Stx1 alone and the TNF-α pretreatment group, although we noted a sparing of renal function when TNF-α was administered before toxin. Compared to that of treatment with Stx1 alone, treatment with TNF-α after toxin altered the renal cytokine profile so that the expression of proinflammatory cytokines TNF-α and interleukin-1β (IL-1β) increased, and the expression of the anti-inflammatory cytokine IL-10 decreased. Increased lethality in mice treated with Stx1 followed by TNF-α was associated with higher numbers of dUTP-biotin nick end labeling-positive renal tubule cells, suggesting that increased lethality involved enhanced apoptosis. These data suggest that the early administration of TNF-α is a candidate interventional strategy blocking disease progression, while TNF-α production after intoxication exacerbates disease.


2018 ◽  
Vol 33 (11) ◽  
pp. 2057-2071 ◽  
Author(s):  
Ramon Alfonso Exeni ◽  
Romina Jimena Fernandez-Brando ◽  
Adriana Patricia Santiago ◽  
Gabriela Alejandra Fiorentino ◽  
Andrea Mariana Exeni ◽  
...  

2019 ◽  
Vol 39 (4) ◽  
Author(s):  
Mouli Tian ◽  
Mei Yang ◽  
Zhenjie Li ◽  
Yiru Wang ◽  
Wei Chen ◽  
...  

Abstract We aimed to investigate the anti-inflammatory role of fluoxetine, a selective serotonin reuptake inhibitor, in microglia (MG) and the mechanisms under oxygen glucose deprivation/reoxygenation (OGD/R). An OGD/R model on BV-2 cells was used for the study of microglia under ischemia/reperfusion injury in ischemic stroke. Lentiviral transfection was applied to knock down IκB-α. Enzyme-linked immunosorbent assay (ELISA) was used for detecting levels of TNF-α, IL-1β, and IL-6, and real-time PCR was used to assess the expression of IκB-α protein. Western blotting was applied to analyze NF-κB-signaling related proteins and Cell Counting Kit-8 (CCK-8) was used for assessing cell viability. Molecular docking and drug affinity responsive target stability (DARTS) assay were used for the detection of the interaction between IκB-α and fluoxetine. We found that fluoxetine decreased the levels of TNF-α, IL-1β, and IL-6 in supernatant as well as NF-κB subunits p65 and p50 in BV-2 cells under OGD/R. Fluoxetine significantly increased the level of IκB-α through the inhibition of IκB-α ubiquitylation and promoted the bonding of IκB-α and fluoxetine in BV-2 cells under OGD/R. Knocking down IκB-α attenuated the decreasing effect of TNF-α, IL-1β, and IL-6 as well as p65 and p50 in BV-2 cells under OGD/R led to by fluoxetine. In conclusion, our present study demonstrated the anti-inflammatory role of fluoxetine and its mechanisms related to the modulation of NF-κB-related signaling in MG under ischemia/reperfusion challenge.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 2804-2804
Author(s):  
Toshihiko Nishimura ◽  
John Morser ◽  
Zhifei Shao ◽  
Lawrence L. Leung

Abstract Hemolytic uremic syndrome (HUS) is characterized by a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. The most common cause of HUS is Shiga toxin (STX)-producing E. coli, and eculizumab, a monoclonal antibody against complement C5, has shown clinical efficacy in some patients. Carboxypeptidase B2 (CPB2) is a metalloprotease activated by the thrombin/thrombomodulin complex that inactivates a number of inflammatory mediators, including complement C3a, and C5a by removing their C-terminal arginine. We hypothesized that in a murine model of STX-induced HUS, Cpb2-/- mice would have exacerbated disease compared to wild type (WT) mice due to excessive C3a and/or C5a in the absence of CPB2. A mouse model of STX-induced HUS was established by giving STX and LPS toxins intraperitoneally. Cpb2-/- mice had worse survival than WT (37% survival vs. 87% at 48h, p=0.0156). At 48h, severe thrombocytopenia developed in both WT and Cpb2-/- mice (WT: 0.096x106/μL; Cpb2-/-: 0.054x106/μL) compared to controls (1.2x106/μL; p>0.0001 vs. either WT or Cpb2-/-), with Cpb2-/- mice showing worse thrombocytopenia. Renal insufficiency was worse in Cpb2-/- mice than WT mice (BUN at 48h: 85 mg/dL vs. 37 mg/dL, p=0.0074; creatinine: 1.33 mg/dL vs. 0.23 mg/dL; p=0.0112, for Cpb2-/- and WT mice respectively, compared with normal baseline BUN and creatinine of 19 mg/dL and 0.1 mg/dL). Cpb2-/- mice developed worse anemia than WT (hemoglobin 9.8 g/dL vs. 12.4 g/dL, p=0.001 in Cpb2-/- vs. WT mice respectively). At 48h, liver function was worse in Cpb2-/- mice than WT mice, while plasma LDH was increased in Cpb2-/- mice more than WT mice. Using a standardized health score, the Cpb2-/- mice were worse than WT mice at all time points. Thus this model recapitulates STX-induced HUS with the Cpb2-/- mice having worse disease than WT. If the animals were treated with STX alone, there were no deaths in either genotype at 48h and only 37.5% mortality in Cpb2-/- mice by 60h compared with no deaths in WT mice. BUN, creatinine, liver enzymes and LDH were increased in both genotypes treated with STX alone compared to untreated mice, but there was no significant difference between the genotypes. Treatment with LPS alone caused thrombocytopenia in both WT and Cpb2-/- mice and LDH, BUN and creatinine levels were higher in Cpb2-/- mice than in WT mice, but there was no death at 48h and no drop in hemoglobin. Thus while either STX alone or LPS alone caused pathological conditions in the mice, the typical triad of HUS was only present when STX and LPS were given in combination. The Cpb2-/- mice had worse disease than WT mice consistent with our hypothesis on the role of CPB2 in inactivating C3a and/or C5a in STX-induced HUS. The potential efficacy of C3a and/or C5a blockade and anti-thrombotic agents will be tested in this model. Disclosures No relevant conflicts of interest to declare.


2007 ◽  
Vol 7 ◽  
pp. 1155-1164 ◽  
Author(s):  
Ramón A. Exeni ◽  
Gabriela C. Fernández ◽  
Marina S. Palermo

Thrombotic microangiopathy and acute renal failure are cardinal features of post-diarrheal hemolytic uremic syndrome (HUS). These conditions are related to endothelial and epithelial cell damage induced by Shiga toxin (Stx), through an interaction with its globotriaosylceramide (Gb3) receptor. Although, Stx is the main pathogenic factor and necessary for HUS development, clinical and experimental evidence suggest that the inflammatory response is able to potentiate Stx toxicity. Lipopolysaccharides (LPS) and neutrophils (PMN) represent two central components of inflammation during a Gram-negative infection. In this regard, patients with high peripheral PMN counts at presentation have a poor prognosis. In the present review, we discuss the contribution of experimental models and patient's studies in an attempt to elucidate the pathogenic mechanisms of HUS.


2009 ◽  
Vol 182 (10) ◽  
pp. 6394-6400 ◽  
Author(s):  
Dorothea Orth ◽  
Abdul Basit Khan ◽  
Asma Naim ◽  
Katharina Grif ◽  
Jens Brockmeyer ◽  
...  

2005 ◽  
Vol 73 (7) ◽  
pp. 4054-4061 ◽  
Author(s):  
D. E. Akiyoshi ◽  
C. M. Rich ◽  
S. O'Sullivan-Murphy ◽  
L. Richard ◽  
J. Dilo ◽  
...  

ABSTRACT Shiga toxin-producing Escherichia coli infections can often lead to the development of hemolytic-uremic syndrome (HUS) in a small percentage of infected humans. Patients with HUS receive only supportive treatment as the benefit of antibiotic therapy remains uncertain. We have previously reported the generation and preclinical evaluation of neutralizing human monoclonal antibodies (HuMAbs) against the Shiga toxins (Stx). In this paper, we describe the expression in Chinese hamster ovary (CHO) cells of 5C12 HuMAb, which is directed against the A subunit of Stx2. The cDNAs of the light and heavy chain immunoglobulin (Ig) variable regions of 5C12 HuMAb were isolated and cloned into an expression vector containing human IgG1 constant regions. The vector was transfected into CHO cells, and transfectants secreting Stx2-specific antibody were screened by an Stx2-specific enzyme-linked immunosorbent assay. The CHO-produced recombinant 5C12 (r5C12) showed similar specificity and binding affinity to Stx2 as the parent hybridoma-produced 5C12. More significantly, the r5C12 displayed the same neutralizing activity as the parent 5C12 in vitro and in vivo. In the mouse toxicity model, both antibodies significantly and equally prolonged survival at a dose of 0.312 μg/mouse. The data showed that since r5C12, produced in CHO cells, was equally effective as the parent 5C12, it is our choice candidate as a potential prophylactic or therapeutic agent against hemolytic-uremic syndrome.


2002 ◽  
Vol 5 (5) ◽  
pp. 472-479 ◽  
Author(s):  
Theodore J. Pysher ◽  
Richard L. Siegler ◽  
Vernon L. Tesh ◽  
Fletcher B. Taylor

von Willebrand Factor (vWF) is stored and released from activated or damaged endothelial cells and platelets, and its multimers have considerable prothrombotic properties. To investigate the role of vWF in the pathogenesis of post-diarrheal (D+) hemolytic uremic syndrome (HUS), we used a baboon model to study vWF expression following the intravenous administration of 100 ng/kg of Shiga toxin 1 (Stx 1), given either as a single dose, or as four divided doses, with and without lipopolysaccharide (LPS). vWF antigen was measured in plasma and urine obtained at 0, 12, 24, 36, 48, and 60 h by enzyme-linked immunosorbent assay (ELISA), and immunohistochemical expression of vWF in renal tissue obtained at autopsy was quantified by image analysis. Animals that received the single dose of Stx 1, or the four divided doses of Stx 1 plus LPS uniformly developed HUS, but those that received divided doses of Stx 1 without LPS, or LPS alone did not. Plasma vWF levels rose significantly in animals that received LPS, with or without Stx 1; but not in those that received Stx 1 alone. Urine vWF levels were generally undetectable. vWF expression was greater in renal tissue of animals that developed HUS than in those that did not, and was seen in both glomeruli, and, especially, peritubular capillaries. Since HUS developed in animals that did not experience a rise in plasma vWF levels, it does not appear that LPS-mediated systemic vWF release is essential to the pathogenesis of HUS in our model. The renal tissue findings, however, suggest a role for Stx-mediated intrarenal vWF release in the acute nephropathy of D+ HUS.


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