Involvement of the Akt/NF-κB Pathways in the HTNV-Mediated Increase of IL-6, CCL5, ICAM-1, and VCAM-1 in HUVECs

Background

Hantaan virus (HTNV) infection causes a severe form of HFRS(hemorrhagic fever with renal syndrome)in Asia. Although HTNV has been isolated for nearly forty years, the pathogenesis of HFRS is still unknown, and little is known regarding the signaling pathway that is activated by the virus.

Methodology/Principal Findings

Cardamonin was selected as a NF-κB inhibitor, and indirect immunofluorescence assays were used to detect the effect of cardamonin on HTNV-infected HUVECs. The effect of cardamonin on the HTNV-induced phosphorylation of Akt and DNA-binding activity of NF-κB were determined using Western blot analysis and electrophoretic mobility shift assays (EMSAs), respectively. Then, flow cytometric and quantitative real-time PCR analyses were performed to quantify the expression levels of the adhesion molecules ICAM-1 and VCAM-1, and the concentrations of IL-6, IL-8, and CCL5 in HUVEC supernatants were examined using ELISA. The results showed that cardamonin did not effect the proliferation of HUVECs or the replication of HTNV in HUVECs. Instead, cardamonin inhibited the phosphorylation of Akt and nuclear transduction of NF-κB and further reduced the expression of the adhesion molecules ICAM-1 and VCAM-1 in HTNV-infected HUVECs. Cardamonin also inhibited the secretion of IL-6 and CCL5, but not IL-8.

Conclusion/Significance

HTNV replication may not be dependent upon the ability of the virus to activate NF-κB in HUVECs. The Akt/NF-κB pathways may be involved in the pathogenesis of HFRS; therefore, cardamonin may serve as a potential beneficial agent for HFRS therapy.     

Soluble ST2 Levels Are Associated with Bleeding in Patients with Severe Leptospirosis

Background

Severe leptospirosis features bleeding and multi-organ failure, leading to shock and death. Currently it is assumed that both exaggerated inflammation and immune suppression contribute to mortality in sepsis. Indeed, several proinflammatory cytokines are reported to be induced during leptospirosis. Toll-like receptors, which play an important role in the initiation of an innate immune response, are inhibited by negative regulators including the membrane-bound ST2 (mST2) receptor. Soluble ST2 (sST2) has been implicated to inhibit signaling through mST2. The aim of this study was to determine the extent of sST2 and (pro-) inflammatory cytokine release in patients with severe leptospirosis.

Methodology and Principal Findings

In an observational study, 68 consecutive cases of severe leptospirosis were included. Soluble ST2 and cytokines (TNF-α, IL-1β, IL-6, IL-8, and IL-10) were repeatedly measured. To determine whether blood cells are a source of sST2 during infection, we undertook an in vitro experiment: human whole blood and peripheral blood mononuclear cells (PBMC) were stimulated with viable pathogenic Leptospira. All patients showed elevated sST2, IL-6, IL-8, and IL-10 levels on admission. Admission sST2 levels correlated with IL-6, IL-8, and IL-10. Thirty-four patients (50%) showed clinical bleeding. Soluble ST2 levels were significantly associated with bleeding overall (OR 2.0; 95%CI: 1.2–3.6) and severe bleeding (OR 5.1; 95%CI: 1.1–23.8). This association was unique, since none of the cytokines showed this correlation. Moreover, sST2 was associated with mortality (OR 2.4; 95%CI: 1.0–5.8). When either whole blood or isolated PBMCs were stimulated with Leptospira in vitro, no sST2 production could be detected.

Conclusions

Patients with severe leptospirosis demonstrated elevated plasma sST2 levels. Soluble ST2 levels were associated with bleeding and mortality. In vitro experiments showed that (white) blood cells are probably not the source. In this regard, sST2 could be an indicative marker for tissue damage in patients suffering from severe leptospirosis.     

Soluble ST2 and Interleukin-33 Levels in Coronary Artery Disease: Relation to Disease Activity and Adverse Outcome

Objectives

ST2 is a receptor for interleukin (IL)-33. We investigated an association of soluble ST2 (sST2) and IL-33 serum levels with different clinical stages of coronary artery disease. We assessed the predictive value of sST2 and IL-33 in patients with stable angina, non-ST elevation myocardial infarction (NSTEMI) and ST elevation myocardial infarction (STEMI).

Methods

We included 373 patients of whom 178 had stable angina, 97 had NSTEMI, and 98 had STEMI. Patients were followed for a mean of 43 months. The control group consisted of 65 individuals without significant stenosis on coronary angiography. Serum levels of sST2 and IL-33 were measured by ELISAs.

Results

sST2 levels were significantly increased in patients with STEMI as compared to patients with NSTEMI and stable angina as well as with controls. IL-33 levels did not differ between the four groups. During follow-up, 37 (10%) patients died and the combined endpoint (all cause death, MI and rehospitalisation for cardiac causes) occurred in 66 (17.6%) patients. sST2 serum levels significantly predicted mortality in the total cohort. When patients were stratified according to their clinical presentation, the highest quintile of sST2 significantly predicted mortality in patients with STEMI, but not with NSTEMI or stable coronary artery disease. sST2 was a significant predictor for the combined endpoint in STEMI patients and in patients with stable angina. Serum levels of IL-33 were not associated with clinical outcome in the total cohort, but the highest quintile of IL-33 predicted mortality in patients with STEMI.

Conclusions

Serum levels of sST2 are increased in patients with acute coronary syndromes as compared to levels in patients with stable coronary artery disease and in individuals without coronary artery disease. sST2 and IL-33 were associated with mortality in patients with STEMI but not in patients with NSTEMI or stable angina.     

ST2 and IL-33 in pregnancy and pre-eclampsia

Normal pregnancy is associated with a mild systemic inflammatory response and an immune bias towards type 2 cytokine production, whereas pre-eclampsia is characterized by a more intense inflammatory response, associated with endothelial dysfunction and a type 1 cytokine dominance. Interleukin (IL)-33 is a newly described member of the IL-1 family, which binds its receptor ST2L to induce type 2 cytokines. A soluble variant of ST2 (sST2) acts as a decoy receptor to regulate the activity of IL-33. In this study circulating IL-33 and sST2 were measured in each trimester of normal pregnancy and in women with pre-eclampsia. While IL-33 did not change throughout normal pregnancy, or between non-pregnant, normal pregnant or pre-eclamptic women, sST2 was significantly altered. sST2 was increased in the third trimester of normal pregnancy (p<0.001) and was further increased in pre-eclampsia (p<0.001). This increase was seen prior to the onset of disease (p<0.01). Pre-eclampsia is a disease caused by placental derived factors, and we show that IL-33 and ST2 can be detected in lysates from both normal and pre-eclampsia placentas. ST2, but not IL-33, was identified on the syncytiotrophoblast layer, whereas IL-33 was expressed on perivascular tissue. In an in vitro placental perfusion model, sST2 was secreted by the placenta into the 'maternal' eluate, and placental explants treated with pro-inflammatory cytokines or subjected to hypoxia/reperfusion injury release more sST2, suggesting the origin of at least some of the increased amounts of circulating sST2 in pre-eclamptic women is the placenta. These results suggest that sST2 may play a significant role in pregnancies complicated by pre-eclampsia and increased sST2 could contribute to the type 1 bias seen in this disorder.     

Paracrine IL-33 stimulation enhances lipopolysaccharide-mediated macrophage activation

Background

IL-33, a member of the IL-1 family of cytokines, provokes Th2-type inflammation accompanied by accumulation of eosinophils through IL-33R, which consists of ST2 and IL-1RAcP. We previously demonstrated that macrophages produce IL-33 in response to LPS. Some immune responses were shown to differ between ST2-deficient mice and soluble ST2-Fc fusion protein-treated mice. Even in anti-ST2 antibody (Ab)-treated mice, the phenotypes differed between distinct Ab clones, because the characterization of such Abs (i.e., depletion, agonistic or blocking Abs) was unclear in some cases.

Methodology/Principal Findings

To elucidate the precise role of IL-33, we newly generated neutralizing monoclonal Abs for IL-33. Exogenous IL-33 potentiated LPS-mediated cytokine production by macrophages. That LPS-mediated cytokine production by macrophages was suppressed by inhibition of endogenous IL-33 by the anti-IL-33 neutralizing mAbs.

Conclusions/Significance

Our findings suggest that LPS-mediated macrophage activation is accelerated by macrophage-derived paracrine IL-33 stimulation.     

Hyperreactivity of Blood Leukocytes in Patients with NAFLD to Ex Vivo Lipopolysaccharide Treatment Is Modulated by Metformin and Phosphatidylcholine but Not by Alpha Ketoglutarate

Introduction and Aims

Toll-like receptor 4 and proinflammatory cytokines play a central role in the progression of nonalcoholic fatty liver disease. We investigated IL-1, IL-6 and TNFα production and toll-like receptor 4 in both—obese and lean patients with non-alcoholic fatty liver disease who met different sets of metabolic syndrome criteria and linked the results with the disease burden.

Materials and Methods

95 subjects were divided into four groups depending on the following criteria: presence or absence of metabolic syndrome and/or non-alcoholic fatty liver disease, glucose tolerance (prediabetes or normoglycemia) and BMI value (obese or lean). We determined the levels of IL-1β, IL-6, TNFα, and monocyte toll-like receptor 4 expression in fresh blood as well as in blood cultures treated with lipopolysaccharide with or without metformin, alphaketoglutarate or phosphatidylcholine supplementation.

Results

The blood leukocytes of patients with non-alcoholic fatty liver disease are hypersensitive to lipopolysaccharide treatment and produce elevated levels of pro-inflammatory cytokines in response to ex vivo treatment with lipopolysaccharide. Moreover, they overexpress toll-like receptor-4. Hyperreactivity was typical mainly for obese patients with non-alcoholic fatty liver disease together with metabolic syndrome and decreased with the severity of disease. Metformin was the most effective in attenuation of hyperreactivity in all groups of patients with non-alcoholic fatty liver disease, but in obese patients the effectiveness of metformin was weaker than in lean. The reduction of cytokine level by metformin was accompanied by the decrease in toll-like receptor-4 expression. phosphatidylcholine also attenuated hyperreactivity to lipopolysaccharide but mainly in obese patients. Alpha ketoglutarate did not modulate cytokines’ level and toll-like receptor 4 expression in non-alcoholic fatty liver disease patients.

Conclusions

Metformin and phosphatidylcholine attenuated lipopolysaccharide induced toll-like receptor 4 overexpression and overproduction of pro-inflammatory cytokines; however, their efficacy depended on combined presence of non-alcoholic fatty liver disease, metabolic syndrome and obesity.     

Cytokine Concentrations in Plasma from Children with Severe and Non-Severe Community Acquired Pneumonia

Background

Children in low and middle-income countries have a high burden of pneumonia. Measuring the cytokine responses may be useful to identify novel markers for diagnosing, monitoring, and treating pneumonia.

Objective

To describe and compare a wide range of inflammatory mediators in plasma from children with WHO-defined severe and non-severe community acquired pneumonia (CAP), and explore to what extent certain mediators are associated with severity and viral detection.

Methods

We collected blood samples from 430 children with severe (n = 43) and non-severe (n = 387) CAP. Plasma from these children were analysed for 27 different cytokines, and we measured the association with age, disease severity and viral detection.

Results

There were generally higher plasma concentrations of several cytokines with both pro-inflammatory and anti-inflammatory effects among children with severe CAP than in children with non-severe CAP. We found significantly higher concentrations of interleukin (IL)-1, IL-4, IL-6, IL-8, IL-9, IL-15, eotaxin, basic fibroblast growth factor (b-FGF), granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor-alpha (TNF-α) in the group of severe CAP. Most of these associations persisted when adjusting for age in linear regression analyses. The cytokine response was strongly associated with age but to a lesser extent with viral etiology.

Conclusion

The plasma concentrations of several cytokines, both with pro-inflammatory and anti-inflammatory effects, were higher among children with severe illness. In particular G-CSF and IL-6 reflected severity and might provide complementary information on the severity of the infection.

Trial registration

ClinicalTrials.gov NCT00148733     

Inflammatory Cytokines in General and Central Obesity and Modulating Effects of Physical Activity

Context

Chronic systemic inflammation in obesity originates from local immune responses in visceral adipose tissue. However, assessment of a broad range of inflammation-mediating cytokines and their relationship to physical activity and adipometrics has scarcely been reported to date.

Objective

To characterize the profile of a broad range of pro- and anti-inflammatory cytokines and the impact of physical activity and energy expenditure in individuals with general obesity, central obesity, and non-obese subjects.

Design, Setting, and Participants

A cross-sectional study comprising 117 obese patients (body mass index (BMI) ≥ 30) and 83 non-obese community-based volunteers.

Main Outcomes Measures

Serum levels of interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, IL-13, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon (IFN)-γ and tumor necrosis factor (TNF)-α were measured. Physical activity and energy expenditure (MET) were assessed with actigraphy. Adipometrics comprised BMI, weight, abdominal-, waist- and hip-circumference, waist to hip ratio (WHR), and waist-to-height-ratio (WHtR).

Results

General obesity was associated with significantly elevated levels of IL-5, IL-10, IL-12, IL-13, IFN-γ and TNF-α, central obesity with significantly elevated IL-5, IL-10, IL-12, IL-13 and IFN-γ-levels. In participants with general obesity, levels of IL-4, IL-10 and IL-13 were significantly elevated in participants with low physical activity, even when controlled for BMI which was negatively associated with physical acitivity. Cytokines significantly correlated with adipometrics, particularly in obese participants.

Conclusions

Results confirm up-regulation of certain pro- and anti-inflammatory cytokines in obesity. In obese subjects, physical activity may lower levels and thus reduce pro-inflammatory effects of cytokines that may link obesity, insulin resistance and diabetes.     

High Spinal Anesthesia Enhances Anti-Inflammatory Responses in Patients Undergoing Coronary Artery Bypass Graft Surgery and Aortic Valve Replacement: Randomized Pilot Study

Background

Cardiac surgery induces many physiologic changes including major inflammatory and sympathetic nervous system responses. Here, we conducted a single-centre pilot study to generate hypotheses on the potential immune impact of adding high spinal anaesthesia to general anaesthesia during cardiac surgery in adults. We hypothesized that this strategy, previously shown to blunt the sympathetic response and improve pain management, could reduce the undesirable systemic inflammatory responses caused by cardiac surgery.

Methods

This prospective randomized unblinded pilot study was conducted on 14 patients undergoing cardiac surgery for coronary artery bypass grafting and/or aortic valve replacement secondary to severe aortic stenosis. The primary outcome measures examined longitudinally were serum pro-inflammatory (IL-6, IL-1b, CCL2), anti-inflammatory (IL-10, TNF-RII, IL-1Ra), acute phase protein (CRP, PTX3) and cardiovascular risk (sST2) biomarkers.

Results

The kinetics of pro- and anti-inflammatory biomarker was determined following surgery. All pro-inflammatory and acute phase reactant biomarker responses induced by surgical stress were indistinguishable in intensity and duration between control groups and those who also received high spinal anaesthesia. Conversely, IL-10 levels were markedly elevated in both intensity and duration in the group receiving high spinal anesthesia (p = 0.005).

Conclusions

This hypothesis generating pilot study suggests that high spinal anesthesia can alter the net inflammatory response that results from cardiac surgery. In appropriately selected populations, this may add incremental benefit by dampening the net systemic inflammatory response during the week following surgery. Larger population studies, powered to assess immune, physiologic and clinical outcomes in both acute and longer term settings, will be required to better assess potential benefits of incorporating high spinal anesthesia.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00348920","term_id":"NCT00348920"}}NCT00348920     

Compartmentalized Cytokine Responses in Hidradenitis Suppurativa

Background

Favorable treatment outcomes with TNF blockade led us to explore cytokine responses in hidradenitis suppurativa (HS).

Methods

Blood monocytes of 120 patients and 24 healthy volunteers were subtyped by flow cytometry. Isolated blood mononuclear cells (PBMCs) were stimulated for cytokine production; this was repeated in 13 severe patients during treatment with etanercept. Cytokines in pus were measured.

Results

CD14^brightCD16^dim inflammatory monocytes and patrolling monocytes were increased in Hurley III patients. Cytokine production by stimulated PBMCs was low compared to controls but the cytokine gene copies did not differ, indicating post-translational inhibition. The low production of IL-17 was restored, when cells were incubated with adalimumab. In pus, high concentrations of pro-inflammatory cytokines were detected. Based on the patterns, six different cytokine profiles were discerned, which are potentially relevant for the choice of treatment. Clinical improvement with etanercept was predicted by increased production of IL-1β and IL-17 by PBMCs at week 8.

Conclusions

Findings indicate compartmentalized cytokine expression in HS; high in pus but suppressed in PBMCs. This is modulated through blockade of TNF.     

High plasma levels of soluble ST2 but not its ligand IL-33 is associated with severe forms of pediatric dengue

Identification of early determinants of dengue disease progression, which could potentially enable individualized patient care are needed at present times. Soluble ST2 (sST2) has been recently reported to be elevated in the serum of children older than 2 years old and adults with dengue infection and it was correlated with secondary infections as well as with severe presentations of the disease. The mechanism by which secreted ST2 is linked to severe dengue and plasma leakage remains unclear. One possibility is that IL-33 ligand may be elevated, contributing to membrane bound ST2 as part of the immune activation in dengue infection. We determined plasma levels of sST2 and the ligand IL-33 in 66 children with acute secondary dengue infections clinically classified using the guidelines of the World Health Organization, 2009. Dengue infection showed significant increases in cytokines IL-12p70, IL-10, IL-8, IL-6, IL-1β and TNFα measured by flow cytometry based assay compared to uninfected individuals. In contrast, IL-33 levels remained unchanged between infected and uninfected individuals. The levels of sST2 positively correlated with values of IL-6 and IL-8 and inversely correlated with number of median value of platelet levels. In addition to circulating cytokine positive correlations we found that sST2 and isoenzyme creatine kinase-MB (CK-MB), a marker of myocardial muscle damage present in severe dengue cases were associated. Our pediatric study concluded that in dengue infections sST2 elevation does not involve concomitant changes of IL-33 ligand. We propose a study to assess its value as a predictor factor of disease severity.     

Plasma Cytokine Levels Fall in Preterm Newborn Infants on Nasal CPAP with Early Respiratory Distress

Introduction

Early nCPAP seems to prevent ventilator-induced lung injury in humans, although the pathophysiological mechanisms underlying this beneficial effect have not been clarified yet.

Objective

To evaluate plasma levels IL-1β, IL-6, IL-8, IL-10, and TNF-α immediately before the start of nCPAP and 2 hours later in preterm infants.

Methods

Prospective cohort including preterm infants with 28 to 35 weeks gestational age with moderate respiratory distress requiring nCPAP. Extreme preemies, newborns with malformations, congenital infections, sepsis, surfactant treatment, and receiving ventilatory support in the delivery room were excluded. Blood samples were collected right before and 2 hours after the start of nCPAP.

Results

23 preterm infants (birth weight 1851±403 grams; GA 32.3±1.7 weeks) were treated with nCPAP. IL-1β, IL-10, TNF-α levels were similar, IL-8 levels were reduced in 18/23 preterm infants and a significant decrease in IL-6 levels was observed after 2 hours of nCPAP. All newborns whose mothers received antenatal steroids had lower cytokine levels at the onset of nCPAP than those whose mothers didn’t receive it; this effect was not sustained after 2 hours of nCPAP.

Conclusion

Early use nCPAP is not associated with rising of plasma pro-inflammatory cytokines and it seems to be a less harmful respiratory strategy for preterm with moderate respiratory distress.     

The Association of Serum Leptin with Mortality in Older Adults

Objective

Elevated levels of serum leptin are associated with increased adiposity and production of pro-inflammatory cytokines. Both cytokines and body adiposity have been shown to predict cardiovascular events and mortality. The primary objective of the present study is to explore the associations between serum leptin and all-cause mortality and mortality from cardiovascular disease (CVD) over a span of 10 years, controlling for body adiposity and proinflammatory cytokines.

Methods

The Health, Aging and Body Composition (Health ABC) study is a prospective cohort of 3,075 older adults aged 70 to 79 years. This analysis includes 2,919 men and women with complete serum leptin and vital status data. Data on all-cause mortality and incident cardiovascular events (including Coronary Heart Disease and Congestive Heart Failure) were collected over 10 years of follow-up (mean 8.4 years).

Results

Women with leptin in quartile 2 and 3 were at lower risk of all-cause mortality, and those with leptin in quartile 2 were at lower risk of mortality from CVD as compared to women with lowest leptin values when adjusted for age, race, site, years of education, alcohol use, smoking, and physical activity. When these associations were additionally adjusted for body fat, C-reactive protein and pro-inflammatory cytokines, women with leptin values in quartile 3 were at lower risk of all-cause mortality and women with leptin in quartile 2 and 3 were at lower risk of mortality from CVD than women with lowest leptin values. These associations were not significant among men after adjusting for body fat and cytokines.

Conclusions

The present study suggests that moderately elevated concentrations of serum leptin are independently associated with lower risk of all-cause mortality and CVD-related mortality among older women. Among men, serum leptin is not associated with reduced risk of all-cause and CVD mortality after controlling for body fat and cytokines.     

Comparison of the Levels of Pro-Inflammatory Cytokines Released in the Vastus Lateralis Muscle of Patients with Fibromyalgia and Healthy Controls during Contractions of the Quadriceps Muscle – A Microdialysis Study

Objective

Fibromyalgia is associated with central hyperexcitability, but it is suggested that peripheral input is important to maintain central hyperexcitability. The primary aim was to investigate the levels of pro-inflammatory cytokines released in the vastus lateralis muscle during repetitive dynamic contractions of the quadriceps muscle in patients with fibromyalgia and healthy controls. Secondarily, to investigate if the levels of pro-inflammatory cytokines were correlated with pain or fatigue during these repetitive dynamic contractions.

Material and Methods

32 women with fibromyalgia and 32 healthy women (controls) participated in a 4 hour microdialysis session, to sample IL-1β, IL-6, IL-8, and TNF from the most painful point of the vastus lateralis muscle before, during and after 20 minutes of repeated dynamic contractions. Pain (visual analogue scale; 0–100) and fatigue Borg’s Rating of Perceived Exertion Scale; 6–20) were assessed before and during the entire microdialysis session.

Results

The repetitive dynamic contractions increased pain in the patients with fibromyalgia (P < .001) and induced fatigue in both groups (P < .001). Perceived fatigue was significantly higher among patients with fibromyalgia than controls (P < .001). The levels of IL-1β did not change during contractions in either group. The levels of TNF did not change during contractions in patients with fibromyalgia, but increased in controls (P < .001) and were significantly higher compared to patients with fibromyalgia (P = .033). The levels of IL-6 and IL-8 increased in both groups alike during and after contractions (P’s < .001). There were no correlations between pain or fatigue and cytokine levels after contractions.

Conclusion

There were no differences between patients with fibromyalgia and controls in release of pro-inflammatory cytokines, and no correlations between levels of pro-inflammatory cytokines and pain or fatigue. Thus, this study indicates that IL-1β, IL-6, IL-8, and TNF do not seem to play an important role in maintenance of muscle pain in fibromyalgia.     

Diminazene Aceturate (Berenil) Modulates the Host Cellular and Inflammatory Responses to Trypanosoma congolense Infection

Background

Trypanosoma congolense are extracellular and intravascular blood parasites that cause debilitating acute or chronic disease in cattle and other domestic animals. Diminazene aceturate (Berenil) has been widely used as a chemotherapeutic agent for trypanosomiasis in livestock since 1955. As in livestock, treatment of infected highly susceptible BALB/c mice with Berenil leads to rapid control of parasitemia and survival from an otherwise lethal infection. The molecular and biochemical mechanisms of action of Berenil are still not very well defined and its effect on the host immune system has remained relatively unstudied. Here, we investigated whether Berenil has, in addition to its trypanolytic effect, a modulatory effect on the host immune response to Trypanosoma congolense.

Methodology/Principal Findings

BALB/c and C57BL/6 mice were infected intraperitoneally with T. congolense, treated with Berenil and the expression of CD25 and FoxP3 on splenic cells was assessed directly ex vivo. In addition, serum levels and spontaneous and LPS-induced production of pro-inflammatory cytokines by splenic and hepatic CD11b⁺ cells were determined by ELISA. Berenil treatment significantly reduced the percentages of CD25⁺ cells, a concomitant reduction in the percentage of regulatory (CD4⁺Foxp3⁺) T cells and a striking reduction in serum levels of disease exacerbating pro-inflammatory cytokines including IL-6, IL-12, TNF and IFN-γ. Furthermore, Berenil treatment significantly suppressed spontaneous and LPS-induced production of inflammatory cytokines by splenic and liver macrophages and significantly ameliorated LPS-induced septic shock and the associated cytokine storm.

Conclusions/Significance

Collectively, these results provide evidence that in addition to its direct trypanolytic effect, Berenil also modulates the host immune response to the parasite in a manner that dampen excessive immune activation and production of pathology-promoting pro-inflammatory cytokines, suggesting that this drug may also be beneficial for treatment of disease conditions caused by excessive production of inflammatory cytokines.     

Disordered IL-33/ST2 Activation in Decidualizing Stromal Cells Prolongs Uterine Receptivity in Women with Recurrent Pregnancy Loss

Decidualization renders the endometrium transiently receptive to an implanting blastocyst although the underlying mechanisms remain incompletely understood. Here we show that human endometrial stromal cells (HESCs) rapidly release IL-33, a key regulator of innate immune responses, upon decidualization. In parallel, differentiating HESCs upregulate the IL-33 transmembrane receptor ST2L and other pro-inflammatory mediators before mounting a profound anti-inflammatory response that includes downregulation of ST2L and increased expression of the soluble decoy receptor sST2. We demonstrate that HESCs secrete factors permissive of embryo implantation in mice only during the pro-inflammatory phase of the decidual process. IL-33 knockdown in undifferentiated HESCs was sufficient to abrogate this pro-inflammatory decidual response. Further, sequential activation of the IL-33/ST2L/sST2 axis was disordered in decidualizing HESCs from women with recurrent pregnancy loss. Signals from these cultures prolonged the implantation window but also caused subsequent pregnancy failure in mice. Thus, Il-33/ST2 activation in HESCS drives an autoinflammatory response that controls the temporal expression of receptivity genes. Failure to constrain this response predisposes to miscarriage by allowing out-of-phase implantation in an unsupportive uterine environment.