Absence Of Systemic Inflammation Research Articles

Long-Lasting Enhanced Cytokine Responses Following SARS-CoV-2 BNT162b2 mRNA Vaccination

The mRNA vaccine against COVID-19 protects against severe disease by the induction of robust humoral and cellular responses. Recent studies have shown the capacity of some vaccines to induce enduring non-specific innate immune responses by the induction of trained immunity, augmenting protection against unrelated pathogens. This study aimed to assess whether the mRNA vaccine BNT162b2 can induce lasting non-specific immune responses in myeloid cells following a three-dose vaccination scheme. In a sample size consisting of 20 healthy individuals from Romania, we assessed inflammatory proteins using the Olink® Target 96 Inflammation panel, as well as ex vivo cytokine responses following stimulations with unrelated PRR ligands. We assessed the vaccine-induced non-specific systemic inflammation and functional adaptations of myeloid cells. Our results revealed the induction of a stimulus- and cytokine-dependent innate immune memory phenotype that became apparent after the booster dose and was maintained eight months later in the absence of systemic inflammation.

Enterococcus Induces MHC-II Expression in the Colonic Epithelium to Aggravate Graft-Versus-Host Disease

Intestinal domination by Enterococcus, a genus of Gram-positive facultative bacteria, has been associated with an increased risk of GVHD mortality in allo-HCT patients and in preclinical models. However, the immunological mechanisms underlying this association remain unclear. Several preclinical studies have demonstrated that MHC-II expression by intestinal epithelial cells (IECs) is involved in allo-antigen presentation and GVHD and can be modulated by the intestinal microbiota. MHC-II genes are constitutively expressed by professional antigen-presenting cells (APCs) but can be induced in non-professional APCs by IFN-γ. Here we reported that Enterococcus could potentially aggravate GVHD through upregulation of MHC-II expression by IECs in an IFN-γ-dependent manner. Using an MHC-disparate mouse model of GVHD (C57BL/6J into BALB/cJ), we profiled the fecal microbiome of GVHD mice by 16S rRNA sequencing and the intestinal epithelium by flow cytometry on day 7 post-transplant. We found that endogenous Enterococcus relative abundance was positively correlated with MHC-II expression by colonic IECs (CD45- CD31- EpCAM+) during GVHD ( Fig. 1a; p=0.0004; 2 replicates; n=19). To determine whether this phenotype occurs in the absence of systemic inflammation, we utilized gnotobiotic mice treated with either E. faecalis, B. producta (a bacteria genus previously associated with improved GVHD outcomes)or PBS via oral gavage. Monocolonization with E. faecalis was sufficient to upregulate MHC-II expression by colonic IECs in non-transplanted (steady-state) animals compared to PBS-treated germfree controls ( Fig. 1b; p=0.0027; 3 replicates; n=8-12/group). On the contrary, monocolonization by B. producta did not induce MHC-II expression by colonic IECs compared to germfree controls ( p=0.96). We also observed that MHC-II upregulation was promoted by specific species within the genus Enterococcus, such that compared to PBS-treated germfree controls, only E. faecalis ( p=0.0007; 3 replicates; n=8-12/group) was able to induce MHC-II expression by colonic IECs, but not E. durans ( p=0.06) , E. gallinarium ( p=0.98) and E. hirae ( p=0.99). Using a Villin-Cre IFN- γ R fl/flmouse model with genetic ablation of the IFN-γ receptor specifically in epithelial cells, we investigated whether MHC-II expression induced by Enterococcus was dependent on IFN-γ signaling. We colonized Villin-Cre pos and Villin-Cre neg littermate controls with E. faecalis via oral gavage after antibiotics decontamination (ampicillin/enrofloxacin) and profiled the intestinal epithelium. We observed that Villin-Cre posmice exhibited a significantly lower MHC-II expression in the small intestine compared to Villin-Cre negmice on day 3 post- Enterococcus colonization ( p=0.012; 2 replicates; n=7/group), suggesting that IFN-γ signaling is necessary to mediate Enterococcus interaction with the intestinal epithelium. Finally, to explore a potential intervention to reduce intestinal inflammation upon Enterococcus domination, we treated GVHD mice with either butyrate-producing B. producta or E. faecalis. Colonization with B. producta reduced fecal Enterococcus burden on day 7 post-transplant ( p=0.007; 2 replicates; n=8/group) and improved survival in GVHD mice, compared to the E. faecalis-colonized group ( p=0.002; 2 replicates; n=18-19/group). We and others have previously shown that butyrate administration can alleviate GVHD through its effects on epithelial homeostasis. To determine whether butyrate could regulate allo-antigen presentation by the intestinal epithelium, we employed the human colorectal adenocarcinoma HT-29 cell culture. We pre-treated the cells with IFNγ (100U/ml) to induce MHC-II expression, then added butyrate (5mM) to the culture for 24 hours. Butyrate treatment was sufficient to suppress MHC-II expression by HT-29 cells, compared to DMSO-treated controls ( p=0.006; 3 replicates; n=6/group). Altogether, our results suggest that one mechanism by which Enterococcus can aggravate GVHD involves the upregulation of MHC-II expression by colonic IECs, and treatment with butyrate might serve as an intervention to prevent intestinal inflammation. Further identification of the upstream mediators involved will provide additional mechanistic insight into the interaction between Enterococcus and the intestinal epithelium at steady state and during GVHD.

Peripheral blood mononuclear cell hyperresponsiveness in patients with premature myocardial infarction without traditional risk factors

An increasing number of patients develop an atherothrombotic myocardial infarction (MI) in the absence of standard modifiable risk factors (SMuRFs). Monocytes and macrophages regulate the development of atherosclerosis, and monocytes can adopt a long-term hyperinflammatory phenotype by epigenetic reprogramming, which can contribute to atherogenesis (called "trained immunity"). We assessed circulating monocyte phenotype and function and specific histone marks associated with trained immunity in SMuRFless patients with MI and matched healthy controls. Even in the absence of systemic inflammation, monocytes from SMuRFless patients with MI had an increased overall cytokine production capacity, with the strongest difference for LPS-induced interleukin-10 production, which was associated with an enrichment of the permissive histone marker H3K4me3 at the promoter region. Considering the lack of intervenable risk factors in these patients, trained immunity could be a promising target for future therapy.

Hypoxemia in the presence or absence of systemic inflammation does not increase blood lactate levels in healthy volunteers.

Elevated lactate levels are a sign of critical illness and may result from insufficient oxygen delivery. We investigated whether hypoxemia and/or systemic inflammation, results in increased lactate levels in healthy volunteers. 30 healthy volunteers were exposed to either 3.5 h of hypoxemia (FiO2 ± 11.5%), normoxemic endotoxemia (FiO2 21%, administration of 2 ng/kg endotoxin), or hypoxemic endotoxemia (n = 10 per group). Blood lactate, hemoglobin, SpO2, PaO2, PaCO2, pH, and hemodynamic parameters were serially measured. Hypoxemic treatment resulted in lower SpO2 (81.7 ± 2.6 and 81.4 ± 2.4% in the hypoxemia and hypoxemic endotoxemia groups, respectively) and hyperventilation with a PaCO2 decrease of 0.8 ± 0.5 and 1.5 ± 0.6 kPa and an increase in pH. Arterial oxygen content (CaO2) decreased by 20.5 ± 2.9 and 23.5 ± 4.4%, respectively. Lactate levels were slightly, but significantly higher in both hypoxemic groups compared with the normoxemic endotoxemia group over time (p < 0.0001 for both groups), but remained below 2.3 mmol/L in all subjects. Whereas PaO2 and SpO2 did not correlate with lactate levels, PaCO2, pH and CaO2 did. Hypoxemia, in the absence or presence of inflammation does not result in relevant increases of lactate. The small increases in lactate observed are likely to be due to hyperventilation-related decreases in glycolysis.

AA amyloidosis without systemic inflammation: when clinical evidence validates predictions of experimental medicine

Amyloid A (AA) amyloidosis is a well-known consequence of chronic inflammatory diseases in which elevated plasma concentrations of serum amyloid A result in amyloid aggregation and organ damage. In this issue, Sikora etal. report, for the first time, an inherited form of AA amyloidosis occurring in the absence of systemic inflammation. This finding may provide novel insights into the pathogenesis of AA amyloidosis, allowing researchers to further dissect the role of inflammation from that of serum amyloidA.

Aging-Related Changes in Erythropoietic Activity and Iron Metabolism in a Mouse Model of Congenital Erythrocytosis with Human Gain-of-Function Erythropoietin Receptor

We previously created and characterized a mouse model of congenital erythrocytosis with low erythropoietin (EPO) levels from a gain-of-function mutation of the human erythropoietin receptor gene (mtHEPOR) (Divoky et al. PNAS. 2001; 98:986; Divoky et al. JMM Berl. 2016; 94:597). These mice develop fetal erythrocytosis, followed by transient amelioration of erythrocytosis in perinatal life, and reappearance at 3-6 weeks of age. Similarly, erythrocytosis is observed in heterozygous mtHEPOR patients postnatally but not at birth. We previously reported dynamic changes of the erythron with iron homeostasis during ontogenesis in these mice (Kralova et al. Blood 2017; 130: 170). We observed that while perinatal mtHEPOR mice exhibit relative iron deficiency, aged mice had iron overload. Here, we evaluated developmentally-determined factors associated with hyperactivation of EPOR signaling which could cause a transition from iron deficiency (neonates) to hyperferremia and increased iron deposition (aged mice). To assess the consequences of different levels of EPOR-JAK2-STAT5 signaling, we studied hetero- and homozygous mtHEPOR mice that differ in their severity of erythrocytosis.We found that prenatally and perinatally, mtHEPOR hetero- and homozygous mice have increased erythroferrone (Erfe) transcripts and reduced hepcidin, consistent with the known inverse correlation between Erfe and hepcidin and in accordance with increased numbers of immature erythroid progenitors in the fetal hepatic circulation. At birth, previously normal Epo expression decreased and remained low in adulthood. Iron deficiency, observed in mtHEPOR hetero- and homozygotes at postnatal day 7, was likely related to increased iron consumption by augmented erythropoiesis at this stage.Postnatally, hepcidin levels increased in mutant mice, accompanied by low Erfe induction and iron accumulation in the liver and spleen as reflected by the upregulation of hepatic Bmp6 expression in mature adult (aged ~6.5 months) and old (~16 months) mtHEPOR homozygotes. We hypothesized that this could be a consequence of diminished iron consumption due to a progressive decline of erythropoiesis in mtHEPOR mice, possibly mediated by premature aging of erythroid progenitors with cell-autonomously increased proliferative history and/or increased inflammation.Indeed, young mutant erythrocytes had decreased erythrocyte survival and expression of a senescent marker CD47, an inhibitor of erythrocytes' phagocytosis. Additionally, a progressive decline in the percentage of Ter119-positive bone marrow cells and immature erythroblasts was observed in mtHEPOR hetero- and homozygotes with aging. Clonogenic assays of old mice revealed suppression of early (BFU-E) and late (CFU-E) erythroid progenitors and myeloid bias of hematopoiesis, paralleled by the up-regulation of PU.1 expression, elevation of platelet counts, and an increase in megakaryocytes chiefly in the bone marrow of mtHEPOR homozygotes. Serum levels of inflammatory cytokines did not indicate systemic inflammation; however, induced transcripts of IL-6, Inf-γ, Tgf-β, and Tnf-α, mainly in mtHEPOR homozygotes showed local bone marrow inflammatory stress. These data indicate progressive attenuation of erythroid drive in mtHEPOR homozygotes, and less so in mtHEPOR heterozygotes, paralleled by a decline in hematocrit levels with aging. In response to attenuated erythropoietic activity, iron consumption was reduced in mtHEPOR mice, leading to iron accumulation in the liver and spleen accompanied by markedly increased hepcidin synthesis.Our data suggest that even in the absence of systemic inflammation, albeit with possible paracrine inflammatory signals, known to affect bone marrow remodeling and hematopoietic aging, life-lasting prolonged activation of EPOR-JAK2-STAT5 signaling promoted exhaustion of erythroid progenitors and resulted in an age-related decline of accelerated erythropoiesis in this mouse model of congenital erythrocytosis with human gain-of-function EPOR.Grant support: Czech grant agencies projects GA17-05988S, NV19-07-00412 and LTAUSA17142, Palacky University project IGA_LF_2021_004. DisclosuresNo relevant conflicts of interest to declare.

Pain catastrophizing hinders Disease Activity Score 28 – erythrocyte sedimentation rate remission of rheumatoid arthritis in patients with normal C‐reactive protein levels

This study aimed to assess the relationship between pain catastrophizing and achievement of 28-joint Disease Activity Score-defined remission of rheumatoid arthritis (RA), considering the presence or absence of systemic inflammation, and to evaluate associated factors for pain catastrophizing. This cross-sectional study included 421 RA outpatients. The relationship between pain catastrophizing and remission was analyzed by adjusting several confounding factors. Univariable and multivariable analyses were performed to determine the relationship between pain catastrophizing and RA-related factors, comorbidities, and lifestyle habits. The prevalence of pain catastrophizing was 26%. Pain catastrophizing was negatively associated with remission (odds ratio 0.62, 95% confidence interval 0.38-1.00, P=.048). A multinomial logistic analysis showed that the presence of pain catastrophizing was an independent factor that was negatively correlated with the achievement of remission in the absence of systemic inflammation (odds ratio 0.51, 95% confidence interval 0.28-0.93, P=.029). Factors associated with elevated ratings on the Pain Catastrophizing Scale were a history of falls within the past year, a Health Assessment Questionnaire score >0.5, and smoking habit. Further, patients' subjective symptoms, including patient global assessment minus evaluator global assessment values ≥20 and high tender joint count minus swollen joint counts, were associated with elevated pain catastrophizing. Pain catastrophizing is a major obstacle to achieving remission in RA patients with normal C-reactive protein levels. Advanced physical disability, smoking habit, and history of falls were associated with pain catastrophizing, in addition to patients' subjective symptoms.

1099 LPS, IL-1β or U.parvum-induced chorioamnionitis in primates alters inflammation and the resident microbiome

Historically, chorioamnionitis has been thought to result from ascending microbes driving inflammation of the chorioamnion, and is associated with preterm labor, perinatal morbidity, and adverse fetal outcomes. However, pathophysiology studies in humans suggest that it results from focal membrane colonization, and we and many others have shown that there is a sparse but present resident intrauterine microbiome. Recently, in some situations preterm chorioamnionitis can be “treated” and pregnancies can continue. Here, we aimed to determine if sterile intraamniotic injection (IA) of IL1β, LPS, or Ureaplasma parvum (UP) induced-chorioamnionitis is associated with alterations in the resident metagenomics composition and its function. Under ultrasound guidance, IA of saline, 1mg LPS (E. coli 055:B5), 10μg IL-1β, or 107 CFU UP were given to preterm (126-132 days) Rhesus macaques (n=54). Fetuses were delivered via sterile cesarean one-week post injection. Oral and vaginal swabs, stool, placental tissue, meconium and amniotic fluid were collected for DNA extraction. DNA was subjected to next-generation sequencing using appropriate contamination “kit” controls. 16S sequencing (n=211) was performed on the V1V3 (454) and was analyzed using QIIME2. WGS sequencing (n=196) was performed on Illumina HiSeq platform, and were filtered and analyzed using krakenuniq. IA injection of IL-1β or LPS induces histologic chorioamnionitis, with significant (p<0.01) increases in neutrophils and proinflammatory cytokines in amniotic fluid. Similar changes were not observed in parallel colon samples (Fig.1) indicating absence of systemic inflammation. These changes were accompanied by significant alterations in the beta diversity of the sparse placental and amniotic fluid microbiome, to control but not in the vaginal, oral or stool microbiomes (Fig.2). Chorioamnionitis is a localized phenomenon rather than a systemic infection, and the variations in amniotic and placental microbiome are consistent with localized inflammation and which alters the sparse but present resident microbiome.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Синдром Макла-Уэллса (клиническое наблюдение)

A clinical case of Muckle-Wells syndrome in a 3-years old child is presented. Muckle-Wells syndrome is among the group of human autoinflammatory diseases (cryopyrin-associated periodic syndromes) – rare genetic diseases characterised by systemic inflammation in absence of other revealed autoimmune and infectious reasons. The disease is characterised by the combination of fever, skin rash and other symptoms accompanied by development of potentially disabling or life-threatening complications. The clinical case presented illustrates the course as well the difficulties in diagnosis and treatment of Muckle-Wells syndrome.

1098 Atrial thickening: a surprisingly "gouty" heart

Abstract Case Presentation A 49 year-old male presented to the emergency department with fever and lower limb myalgia for 5 days. His past history was notable for acute episodes of microcrystalline pyrophosphate oligoarthritis for which he was receiving allopurinol 100mg, colchicine 1mg and prednisolone 5mg. Physical examination was unrevealing. Laboratory workup showed normocytic normochromic anemia (Hb 12.8g/dL), leukocytosis (22 490 /mm3), neutrophilia (86.8%), increased C-reactive protein (CRP 26mg/dL), low procalcitonin (0.82ng/mL) and mildly elevated creatinine-kinase (83 UI/L). The patient was admitted with fever of unknown origin and started on ceftriaxone after blood and urine cultures. He remained febrile with persistently heightened inflammation. Cultures, infectious and auto-immune tests, bone marrow biopsy, myelogram and abdominopelvic CT scan were negative. Three weeks later, syncope due to complete atrioventricular (AV) block led to temporary pacemaker implantation. Transoesophageal echocardiography (TOE) revealed a left atrial (LA) wall thickening, evident on MRI as an 8-10mm T2-hyperintensity sign, with right atrial (RA) and ventricular sparing. PET/CT scan showed an 18F FDG uptake exclusively in the LA. As a neoplasia was highly suspected, a transspeptal biopsy was attempted, yet the sample was scarce for analysis. Thus, a biopsy via sternotomy was performed, now sampling both the LA and RA. Indeed, repeated TOE showed de novo RA involvement with a prominent nodular finding (19x24mm) in the lateral wall. Myocyte inflammation and necrosis accompanied with granulocyte infiltration (mostly neutrophils but also eosinophils) was observed in all samples. There were no findings suggestive of neoplasia. The patient was still on allopurinol, which has been reported to involve the myocardium in a late (type IV) hypersensitivity reaction (the so-called DRESS syndrome), even in the absence of systemic inflammation. Thus, allopurinol was stopped and 1mg/Kg prednisolone was started. The patient significantly improved and was discharged home with negative CRP the following two weeks. After 1 month, MRI was repeated and no atrial inflammation was found. After 4 months follow-up, he is doing well on 2.5mg of prednisolone and febuxostat 80mg.

Abstract C19: Impaired adaptation to negative energy balance in pancreatic cancer-associated wasting

Abstract Purpose/Objectives: The disease-associated wasting condition cachexia is a common complication of pancreatic ductal adenocarcinoma (PDAC) that impacts quality of life and portends poor survival. Undernutrition is a major driver of wasting in PDAC, yet cachexia remains refractory to nutritional supplementation. By modifying nutritional challenges at different stages of cachexia development, we sought to understand the relative contributions of undernutrition and metabolic reprogramming on adipose and skeletal muscle wasting. Materials/Methods: Adult mice received orthotopic PDAC tumor injections (KrasG12D; p53R172H/+; Pdx1-cre) or sham injections. Mice were fasted or food restricted at different times during tumor growth in a series of 2x2 factorial studies. Anthropometrics, voluntary wheel running activity, and body composition were measured throughout study. Blood glucose and ketones were measured by glucometer and ketometer. Ketogenic potential was assessed using octanoate challenge after fasting. Liver mRNA levels were measured using qPCR. Hepatic IL-6 signaling was assessed using qPCR and ELISA for plasma IL-6. Results: PDAC mice maintained food intake and wheel running for 8 days after tumor injection, before progressive decline. Loss of adipose mass in PDAC mice occurred only in the context of decreased nutrition, whereas loss of lean mass preceded decreases in food intake. Overnight fasting mitigated differences in fat mass between groups, whereas the effect of fasting on skeletal muscle loss was similar in PDAC and control mice. Fasting blood glucose and ketogenic potential were lower in PDAC mice, suggesting impaired hepatic response to metabolic stress. In the liver, glycolytic genes were increased, whereas gluconeogenic and ketogenic genes were decreased in PDAC mice. Wasting and hepatic reprogramming occurred independently of hepatic IL-6 signaling. Conclusions: Undernutrition drives PDAC-associated adipose wasting, yet muscle wasting occurs prior to changes in food intake and in the absence of systemic inflammation. Hepatic macronutrient partitioning and metabolic gene expression are altered in PDAC, implicating impaired adaptive responses to negative energy balance in PDAC-associated cachexia. Citation Format: Heike Mendez, Xinxia Zhu, Brennan Olsen, Daniel L. Marks, Aaron J. Grossberg. Impaired adaptation to negative energy balance in pancreatic cancer-associated wasting [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr C19.

Epithelial IL-6 trans-signaling defines a new asthma phenotype with increased airway inflammation

Although several studies link high levels of IL-6 and soluble IL-6 receptor (sIL-6R) to asthma severity and decreased lung function, the role of IL-6 trans-signaling (IL-6TS) in asthmatic patients is unclear. We sought to explore the association between epithelial IL-6TS pathway activation and molecular and clinical phenotypes in asthmatic patients. An IL-6TS gene signature obtained from air-liquid interface cultures of human bronchial epithelial cells stimulated with IL-6 and sIL-6R was used to stratify lung epithelial transcriptomic data (Unbiased Biomarkers in Prediction of Respiratory Disease Outcomes [U-BIOPRED] cohorts) by means of hierarchical clustering. IL-6TS-specific protein markers were used to stratify sputum biomarker data (Wessex cohort). Molecular phenotyping was based on transcriptional profiling of epithelial brushings, pathway analysis, and immunohistochemical analysis of bronchial biopsy specimens. Activation of IL-6TS in air-liquid interface cultures reduced epithelial integrity and induced a specific gene signature enriched in genes associated with airway remodeling. The IL-6TS signature identified a subset of patients with IL-6TS-high asthma with increased epithelial expression of IL-6TS-inducible genes in the absence of systemic inflammation. The IL-6TS-high subset had an overrepresentation of frequent exacerbators, blood eosinophilia, and submucosal infiltration of T cells and macrophages. In bronchial brushings Toll-like receptor pathway genes were upregulated, whereas expression of cell junction genes was reduced. Sputum sIL-6R and IL-6 levels correlated with sputum markers of remodeling and innate immune activation, in particular YKL-40, matrix metalloproteinase 3, macrophage inflammatory protein 1β, IL-8, and IL-1β. Local lung epithelial IL-6TS activation in the absence of type 2 airway inflammation defines a novel subset of asthmatic patients and might drive airway inflammation and epithelial dysfunction in these patients.

Systemic Inflammation-Associated Proteins and Retinopathy of Prematurity in Infants Born Before the 28th Week of Gestation.

PurposeTo assess the association between systemic levels of inflammation-associated proteins and severe retinopathy of prematurity (ROP) in extremely preterm infants.MethodsWe collected whole blood on filter paper on postnatal days 1, 7, 14, 21, and 28 from 1205 infants born before the 28th week of gestation, and measured the concentrations of 27 inflammation-associated, angiogenic, and neurotrophic proteins. We calculated odds ratios with 95% confidence intervals for the association between top quartile concentrations of each protein and prethreshold ROP.ResultsDuring the first three weeks after birth, high concentrations of VEGF-R1, myeloperoxidase (MPO), IL-8, intercellular adhesion molecule (ICAM)-1, matrix metalloproteinase 9, erythropoietin, TNF-α, and basic fibroblast growth factor were associated with an increased risk for prethreshold ROP. On day 28, high levels of serum amyloid A, MPO, IL-6, TNF-α, TNF-R1/-R2, IL-8, and ICAM-1 were associated with an increased risk. Top quartile concentrations of the proinflammatory cytokines TNF-α and IL-6 were associated with increased risks of ROP when levels of neuroprotective proteins and growth factors, including BDNF, insulin-like growth factor 1, IGFBP-1, VEGFR-1 and -2, ANG-1 and PlGF, were not in the top quartile. In contrast, high concentrations of NT-4 and BDNF appeared protective only in infants without elevated inflammatory mediators.ConclusionsSystemic inflammation during the first postnatal month was associated with an increased risk of prethreshold ROP. Elevated concentrations of growth factors, angiogenic proteins, and neurotrophins appeared to modulate this risk, and were capable of reducing the risk even in the absence of systemic inflammation.

Successful nonoperative management of uncomplicated appendicitis: predictors and outcomes

BackgroundOur objective was to identify predictors of successful nonoperative management (NOM) of uncomplicated appendicitis. We hypothesized that the absence of diabetes, absence of an appendicolith, short duration of symptoms, absence of systemic inflammation, and low modified Alvarado score would predict successful NOM. MethodsWe performed a retrospective cohort analysis of 81 consecutive patients who underwent NOM of uncomplicated appendicitis. Successful NOM was defined as resolution of appendicitis with antibiotics alone and no recurrent appendicitis within 180 days. Patients with successful NOM (n = 36) were compared with patients who failed NOM (n = 45). Multivariable logistic regression was used to identify predictors of successful NOM, expressed as odds ratios (ORs) with 95% confidence intervals. Model strength was assessed by calculating area under the receiver operating characteristic curve (AUC). ResultsPatient age (35 years), the American Society of Anesthesiologists class (2.0), and Charlson comorbidity index (0.0) were similar between groups. Independent predictors of successful NOM were duration of symptoms prior to admission >25 hours: OR 4.17 (1.42-12.24), maximum temperature within 6 hours of admission <37.3°C: OR 8.07 (1.79-36.38), modified Alvarado score <4: OR 9.06 (1.26-64.93), and appendiceal diameter <13 mm: OR 17.55 (1.30-237.28); model AUC: 0.81 (0.72-0.90). ConclusionsPatients with a longer duration of symptoms prior to admission were more likely to have successful NOM. Other independent predictors of successful NOM included lower temperature, lower modified Alvarado score, and smaller appendiceal diameter. These findings provide a framework for clinical decision-making and large-scale derivation and validation of a model to predict successful NOM of uncomplicated appendicitis.

The Association between Anti-Nuclear Antibodies and Obesity is Likely Mediated by Abdominal Adiposity and Systemic Inflammation

Background: Obesity and abdominal adiposity have been associated with inflammation as have the presence of anti-nuclear antibodies (ANAs). It was recently reported that there is a decreased likelihood of ANAs in the obese general population. To examine this relationship we used data from adult participants in the National Health and Nutrition and Examination Survey 1999-2004. Methods: Participants were excluded if they reported a history of arthritis other than osteoarthritis, thyroid or liver disease, or steroid use so as to rule out a history of possible prior autoimmune disease. We strictly defined a positive ANA as a titer ≥ 1:160. Overweight and obesity were classified using traditional BMI criteria. High and low C-reactive protein (CRP) were defined using the 75th percentile cutpoint as ≥0.42 and <0.42 mg/dL, respectively. Dual-energy X-ray absorptiometry (DEXA) was used to determine body composition. Logistic regression models were created to examine associations with ANA status. Results: 2552 participants were included in our analyses. Obese participants were older (p<0.001), more likely to be men (p=0.004) and to have comorbidities, and had higher levels of CRP (<0.001). After multivariable adjustment, obesity was associated with a decreased odds of having ANAs (OR 0.78, 95%CI 0.62-0.99). However when adding log-transformed CRP into our model, this association was no longer significant (OR 0.85, 95%CI 0.62-1.15), and there was evidence of effect modification by CRP (p=0.12). Among participants with low CRP, obesity was again associated with a reduced likelihood of ANA positivity (OR 0.69, 95%CI 0.48-0.99), but a trend was seen in the opposite direction in those with high CRP (OR 1.77, 95%CI 0.81-3.88). When looking at the 1143 obese and overweight participants with low CRP, ANA positivity was associated with a higher prevalence of cardiovascular disease (p=0.02) and higher % total body fat (p=0.007), trunk fat (p=0.02), and non-trunk fat (p=0.004). This association, however, was not found in the high CRP group. Conclusion: In the general population the association of obesity with ANA is modified by the presence of systemic inflammation as measured by CRP, where the inverse association previously found is eliminated when controlling for CRP. This inverse relationship remains among obese participants with low CRP, when these obese and overweight participants are ANA positive; it is associated with greater total body and trunk fat. It is possible that body composition is driving autoimmunity in the general population even in the absence of systemic inflammation.

An Nlrc4 mutation associated with systemic hyperinflammation drives spontaneous non-hematopoietic IL-18 hyperproduction

Abstract Macrophage activation syndrome (MAS) is a life-threatening sepsis-like hyperinflammatory state arising in certain infectious and rheumatic diseases. Previous genetic associations have implicated genes critical for perforin-mediated cytotoxicity. However, we recently identified that activating mutations in inflammasome component NLRC4 lead to MAS and early-onset enterocolitis. Patients with NLRC4-MAS also have chronically and extraordinarily elevated serum IL-18. Notably, disease-causing mutations in other inflammasomes do not cause MAS or chronic IL-18 elevation. In vitro, IL-1b production by THP1 cells expressing various NLRC4 patient mutations correlated with disease severity and identified pathogenic clusters in the molecular structure. To further study the function of NLRC4, we created a mouse bearing the T337S point mutation. Like NLRC4-MAS patients, NLRC4-T337S mice demonstrate elevated serum IL-18 in the absence of systemic inflammation. However, macrophages from NLRC4-T337S mice did not demonstrate enhanced IL-1β or IL-18 production. Correspondingly, bone marrow chimeras demonstrated that IL-18 hyperproduction was derived from non-hematopoietic cells. NLRC4-T337S mice did not demonstrate more severe disease in response to repeated systemic stimulation through TLR9 or TLR4, nor upon LCMV infection, but developed colitis with IL-10 receptor blockade. These results suggest intestinal epithelia, which express both NLRC4 and proIL-18, may be a source of pathogenic IL-18 in this model. Future work will clarify the source(s) of excessive IL-18 and identify how chronic IL-18 effects on gut homeostasis and T and NK cell responses may promote systemic hyperinflammation.

Short-term hyperoxia does not exert immunologic effects during experimental murine and human endotoxemia.

Oxygen therapy to maintain tissue oxygenation is one of the cornerstones of critical care. Therefore, hyperoxia is often encountered in critically ill patients. Epidemiologic studies have demonstrated that hyperoxia may affect outcome, although mechanisms are unclear. Immunologic effects might be involved, as hyperoxia was shown to attenuate inflammation and organ damage in preclinical models. However, it remains unclear whether these observations can be ascribed to direct immunosuppressive effects of hyperoxia or to preserved tissue oxygenation. In contrast to these putative anti-inflammatory effects, hyperoxia may elicit an inflammatory response and organ damage in itself, known as oxygen toxicity. Here, we demonstrate that, in the absence of systemic inflammation, short-term hyperoxia (100% O2 for 2.5 hours in mice and 3.5 hours in humans) does not result in increased levels of inflammatory cytokines in both mice and healthy volunteers. Furthermore, we show that, compared with room air, hyperoxia does not affect the systemic inflammatory response elicited by administration of bacterial endotoxin in mice and man. Finally, neutrophil phagocytosis and ROS generation are unaffected by short-term hyperoxia. Our results indicate that hyperoxia does not exert direct anti-inflammatory effects and temper expectations of using it as an immunomodulatory treatment strategy.

Intraperitoneal lidocaine hydrochloride for prevention of intraperitoneal adhesions following laparoscopic genitourinary tract surgery in ewes

Adhesion formation involving the genitourinary tract is common following laparoscopic procedures. To evaluate the effectiveness of intraperitoneal lidocaine hydrochloride 1% solution for the prevention of abdominal adhesions, twenty four Santa Ines ewes submitted to laparoscopic ovum pick-up, uterine puncture and local rinsing, were randomly distributed into two groups of 12 animals, according to rinsing solution: normal saline (SG) or 1% lidocaine hydrochloride solution (LG). Laparoscopy for manipulation of the reproductive tract (uterine puncture trauma model and ovum pick-up) was applied. A standard laparoscopic approach using three ports in triangulation was employed. The uterus and ovaries were rinsed at the end of the procedure (using either saline or lidocaine hydrochloride) for removal of blood clots from the ovaries and uterine horn surfaces. Inflammation was assessed postoperatively by plasma fibrinogen, and all animals underwent a second laparoscopic procedure 21days after surgery for macroscopic assessment of adhesion formation. Four cases of adhesion were observed in each group. The plasma fibrinogen did not differ between groups and among different time points, indicating an absence of systemic inflammation following laparoscopic procedures. There were no significant differences between treatments. Both normal saline and 1% lidocaine hydrochloride were similarly effective in the prevention of adhesion formation.

Su1734 Relieving Mechanism of Exogenous Angiotensin II, III & IV to Chronic and Refractory Constipation: Stimulating Intestinal Secretion and Motility in Human

Background Skeletal muscle is the major reservoir of body proteins and it can be affected in conditions associated to altered protein turnover and metabolism such as cancer. Although severe wasting is seen primarily in patients with advanced malignancy, some of them present degree of wasting at the onset of disease. Autophagy has been recently described to play a relevant role inmuscle wasting.Materials andMethodsWeperformedmorphometric studies and immunohistochemical analyses on intraoperative rectus abdominis muscle biopsies from 50 consecutive weight stable colorectal patients and 25 weight-stable patients operated for non-inflammatory benign diseases with no clinical signs of myopathies. Biochemical and molecular analyses have been performed in order to evaluate protein profile, the presence of autophagy induction and their correlation with clinical outcome. Results In cancer patients, we observed a subclinical myopathy characterized by an abnormal distribution of myonuclei relocated from the periphery inside themyofiber. The percentage ofmyofibers with abnormally located myonuclei was significantly higher in patients (median= 9%) compared to controls (median= 2.7%) (p=0.0002). Analyses on serum samples showed that, in the absence of systemic inflammation, in the prevalence of cancer patients the levels of albumin and prealbumin were below the normal range and the mean value was significantly lower compared to that detected in controls (albumin: 34.82 ± 5.8 g/L vs 45.2 ± 5.3, p< 0.01; prealbumin: 174.38±57.86 mg/L vs 264.00±69.73, p<0.001). Molecular analyses showed an accumulation of p62, a typical marker of autophagy induction, significantly higher in cancer patients compared to controls. Follow-up was 38 ± 12 months. Deceases in patients' group were 18% (9/50) and cancer relapse occurred in 32% (16/50) patients. We found an inverse correlation between the number of abnormally nucleated myofibers and the presence of lymph node metastasis (N+) (n)=-0.64 (p=0.002). Cancer relapse was correlated with low serum levels of prealbumin (156.59 ± 44.22 mg/L in cancer relapse vs 190.62 ± 57.23 mg/L in patients without relapse; p = 0.08) and high levels of p62 in myofibers of cancer patients (Tab.1).Conclusions Colorectal cancer patients have a subclinical myopathy characterized by myofibers with internally located myonuclei. In the absence of inflammation, cancer patients show low levels of prealbumin and albumin as markers of altered protein turnover and persistent high levels of p62 in myofibers as expression of autophagy induction with an impairment in physiological autophagic flux. Up to now our data indicate the presence of an altered protein turnover at an early stage of disease, with an impairment in the physiological autophagic flux, that could be predictive of cancer relapse and onset of cancer cachexia.

Su1733 Altered Protein Profile and Impairment of Physiological Autophagic Flux in Myofibers Could Be Predictive of Relapse in Colorectal-Cancer Patients at an Early Stage of Disease

Background Skeletal muscle is the major reservoir of body proteins and it can be affected in conditions associated to altered protein turnover and metabolism such as cancer. Although severe wasting is seen primarily in patients with advanced malignancy, some of them present degree of wasting at the onset of disease. Autophagy has been recently described to play a relevant role inmuscle wasting.Materials andMethodsWeperformedmorphometric studies and immunohistochemical analyses on intraoperative rectus abdominis muscle biopsies from 50 consecutive weight stable colorectal patients and 25 weight-stable patients operated for non-inflammatory benign diseases with no clinical signs of myopathies. Biochemical and molecular analyses have been performed in order to evaluate protein profile, the presence of autophagy induction and their correlation with clinical outcome. Results In cancer patients, we observed a subclinical myopathy characterized by an abnormal distribution of myonuclei relocated from the periphery inside themyofiber. The percentage ofmyofibers with abnormally located myonuclei was significantly higher in patients (median= 9%) compared to controls (median= 2.7%) (p=0.0002). Analyses on serum samples showed that, in the absence of systemic inflammation, in the prevalence of cancer patients the levels of albumin and prealbumin were below the normal range and the mean value was significantly lower compared to that detected in controls (albumin: 34.82 ± 5.8 g/L vs 45.2 ± 5.3, p< 0.01; prealbumin: 174.38±57.86 mg/L vs 264.00±69.73, p<0.001). Molecular analyses showed an accumulation of p62, a typical marker of autophagy induction, significantly higher in cancer patients compared to controls. Follow-up was 38 ± 12 months. Deceases in patients' group were 18% (9/50) and cancer relapse occurred in 32% (16/50) patients. We found an inverse correlation between the number of abnormally nucleated myofibers and the presence of lymph node metastasis (N+) (n)=-0.64 (p=0.002). Cancer relapse was correlated with low serum levels of prealbumin (156.59 ± 44.22 mg/L in cancer relapse vs 190.62 ± 57.23 mg/L in patients without relapse; p = 0.08) and high levels of p62 in myofibers of cancer patients (Tab.1).Conclusions Colorectal cancer patients have a subclinical myopathy characterized by myofibers with internally located myonuclei. In the absence of inflammation, cancer patients show low levels of prealbumin and albumin as markers of altered protein turnover and persistent high levels of p62 in myofibers as expression of autophagy induction with an impairment in physiological autophagic flux. Up to now our data indicate the presence of an altered protein turnover at an early stage of disease, with an impairment in the physiological autophagic flux, that could be predictive of cancer relapse and onset of cancer cachexia.