Evaluation of 9 biomarkers for predicting 10-year cardiovascular risk in patients undergoing coronary angiography: findings from the LUdwigshafen RIsk and Cardiovascular Health (LURIC) study.

BACKGROUND Conventional factors do not fully explain the distribution of cardiovascular outcomes. Biomarkers are known to participate in well-established pathways associated with cardiovascular disease, and may therefore provide further information over and above conventional risk factors. This study sought to determine whether individual and/or combined assessment of 9 biomarkers improved discrimination, calibration and reclassification of cardiovascular mortality. METHODS 3267 patients (2283 men), aged 18-95 years, at intermediate-to-high-risk of cardiovascular disease were followed in this prospective cohort study. Conventional risk factors and biomarkers were included based on forward and backward Cox proportional stepwise selection models. RESULTS During 10-years of follow-up, 546 fatal cardiovascular events occurred. Four biomarkers (interleukin-6, neutrophils, von Willebrand factor, and 25-hydroxyvitamin D) were retained during stepwise selection procedures for subsequent analyses. Simultaneous inclusion of these biomarkers significantly improved discrimination as measured by the C-index (0.78, P = 0.0001), and integrated discrimination improvement (0.0219, P<0.0001). Collectively, these biomarkers improved net reclassification for cardiovascular death by 10.6% (P<0.0001) when added to the conventional risk model. CONCLUSIONS In terms of adverse cardiovascular prognosis, a biomarker panel consisting of interleukin-6, neutrophils, von Willebrand factor, and 25-hydroxyvitamin D offered significant incremental value beyond that conveyed by simple conventional risk factors.

A Dose-Response Strategy Reveals Differences between Normal-Weight and Obese Men in Their Metabolic and Inflammatory Responses to a High-Fat Meal.

A dose-response strategy may not only allow investigation of the impact of foods and nutrients on human health but may also reveal differences in the response of individuals to food ingestion based on their metabolic health status. In a randomized crossover study, we challenged 19 normal-weight (BMI: 20-25 kg/m(2)) and 18 obese (BMI: >30 kg/m(2)) men with 500, 1000, and 1500 kcal of a high-fat (HF) meal (60.5% energy from fat). Blood was taken at baseline and up to 6 h postprandially and analyzed for a range of metabolic, inflammatory, and hormonal variables, including plasma glucose, lipids, and C-reactive protein and serum insulin, glucagon-like peptide-1, interleukin-6 (IL-6), and endotoxin. Insulin was the only variable that could differentiate the postprandial response of normal-weight and obese participants at each of the 3 caloric doses. A significant response of the inflammatory marker IL-6 was only observed in the obese group after ingestion of the HF meal containing 1500 kcal [net incremental AUC (net iAUC) = 22.9 ± 6.8 pg/mL × 6 h, P = 0.002]. Furthermore, the net iAUC for triglycerides significantly increased from the 1000 to the 1500 kcal meal in the obese group (5.0 ± 0.5 mmol/L × 6 h vs. 6.0 ± 0.5 mmol/L × 6 h, P = 0.015) but not in the normal-weight group (4.3 ± 0.5 mmol/L × 6 h vs. 4.8 ± 0.5 mmol/L × 6 h, P = 0.31). We propose that caloric dose-response studies may contribute to a better understanding of the metabolic impact of food on the human organism. This study was registered at clinicaltrials.gov as NCT01446068.

Increased expression of heat shock protein 90 in keratinocytes and mast cells in patients with psoriasis.

BACKGROUND Psoriasis is a chronic inflammatory skin disease and various stress factors mediate inflammation. Heat shock protein (HSP) 90 plays an important role in cell survival; cytokine signaling, such as interleukin-17 receptor signaling; and immune responses. OBJECTIVE We sought to elucidate protein expression and distribution of HSP90 in psoriasis. METHODS HSP90 expression and its cellular source were analyzed on normal-appearing, nonlesional, lesional, and ustekinumab-treated psoriatic skin using immunohistochemistry and double immunofluorescence. RESULTS HSP90α, the inducible isoform of HSP90, was significantly up-regulated in epidermal keratinocytes and mast cells of lesional skin and down-regulated after ustekinumab therapy. LIMITATIONS There was a limited sample size. CONCLUSIONS HSP90 from keratinocytes and mast cells is a key regulator of psoriatic inflammation and HSP90 inhibitors may represent a novel therapeutic approach to the disease.

IL1B and DEFB1 Polymorphisms Increase Susceptibility to Invasive Mold Infection After Solid Organ Transplantation.

BACKGROUND  Single nucleotide polymorphisms (SNPs) in immune genes have been associated with susceptibility to invasive mold infection (IMI) among hematopoietic stem cell (HSCT) but not solid organ transplant (SOT) recipients. METHODS  24 SNPs from systematically selected genes were genotyped among 1101 SOT recipients (715 kidneys, 190 liver, 102 lungs, 79 hearts, 15 other) from the Swiss Transplant Cohort Study. Association between SNPs and the endpoint were assessed by log-rank test and Cox regression models. Cytokine production upon Aspergillus stimulation was measured by ELISA in PBMCs from healthy volunteers and correlated with relevant genotypes. RESULTS  Mold colonization (N=45) and proven/probable IMI (N=26) were associated with polymorphisms in interleukin-1 beta (IL1B, rs16944; log-rank test, recessive mode, colonization P=0.001 and IMI P=0.00005), interleukin-1 receptor antagonist (IL1RN, rs419598; P=0.01 and P=0.02) and β-defensin-1 (DEFB1, rs1800972; P=0.001 and P=0.0002, respectively). The associations with IL1B and DEFB1 remained significant in a multivariate regression model (IL1B rs16944 P=0.002; DEFB1 rs1800972 P=0.01). Presence of two copies of the rare allele of rs16944 or rs419598 was associated with reduced Aspergillus-induced IL-1β and TNFα secretion by PBMCs. CONCLUSIONS  Functional polymorphisms in IL1B and DEFB1 influence susceptibility to mold infection in SOT recipients. This observation may contribute to individual risk stratification.

Engraftment of autologous bone marrow cells into the injured cranial cruciate ligament in dogs

Current research indicates that exogenous stem cells may accelerate reparative processes in joint disease but, no previous studies have evaluated whether bone marrow cells (BMCs) target the injured cranial cruciate ligament (CCL) in dogs. The objective of this study was to investigate engraftment of BMCs following intra-articular injection in dogs with spontaneous CCL injury. Autologous PKH26-labelled BMCs were injected into the stifle joint of eight client-owned dogs with CCL rupture. The effects of PKH26 staining on cell viability and PKH26 fluorescence intensity were analysed in vitro using a MTT assay and flow cytometry. Labelled BMCs in injured CCL tissue were identified using fluorescence microscopy of biopsies harvested 3 and 13 days after intra-articular BMC injection. The intensity of PKH26 fluorescence declines with cell division but was still detectable after 16 days. Labelling with PKH26 had no detectable effect on cell viability or proliferation. Only rare PKH26-positive cells were present in biopsies of the injured CCL in 3/7 dogs and in synovial fluid in 1/7 dogs. No differences in transforming growth factor-beta1, and interleukin-6 before and after BMC treatment were found and no clinical complications were noted during a 1 year follow-up period. In conclusion, BMCs were shown to engraft to the injured CCL in dogs when injected into the articular cavity. Intra-articular application of PKH26-labelled cultured mesenchymal stem cells is likely to result in higher numbers of engrafted cells that can be tracked using this method in a clinical setting.

A tick-borne encephalitis model in infant rats infected with langat virus

Tick-borne encephalitis virus (TBEV) is the causative agent of human TBE, a severe infection that can cause long-lasting neurologic sequelae. Langat virus (LGTV), which is closely related to TBEV, has a low virulence for human hosts and has been used as a live vaccine against TBEV. Tick-borne encephalitis by natural infection of LGTV in humans has not been described, but one of 18,500 LGTV vaccinees developed encephalitis. The pathogenetic mechanisms of TBEV are poorly understood and, currently, no effective therapy is available. We developed an infant rat model of TBE using LGTV as infective agent. Infant Wistar rats were inoculated intracisternally with 10 focus-forming units of LGTV and assessed for clinical disease and neuropathologic findings at Days 2, 4, 7, and 9 after infection. Infection with LGTV led to gait disturbance, hypokinesia, and reduced weight gain or weight loss. Cerebrospinal fluid concentrations of RANTES, interferon-γ, interferon-β, interleukin-6, and monocyte chemotactic protein-1 were increased in infected animals. The brains of animals with LGTV encephalitis exhibited characteristic perivascular inflammatory cuffs and glial nodules; immunohistochemistry documented the presence of LGTV in the thalamus, hippocampus, midbrain, frontal pole, and cerebellum. Thus, LGTV meningoencephalitis in infant rats mimics important clinical and histopathologic features of human TBE. This new model provides a tool to investigate disease mechanisms and to evaluate new therapeutic strategies against encephalitogenic flaviviruses.

Cytotoxic CD8+ T cells stimulate hematopoietic progenitors by promoting cytokine release from bone marrow mesenchymal stromal cells.

Cytotoxic CD8(+) T cells (CTLs) play a major role in host defense against intracellular pathogens, but a complete clearance of pathogens and return to homeostasis requires the regulated interplay of the innate and acquired immune systems. Here, we show that interferon γ (IFNγ) secreted by effector CTLs stimulates hematopoiesis at the level of early multipotent hematopoietic progenitor cells and induces myeloid differentiation. IFNγ did not primarily affect hematopoietic stem or progenitor cells directly. Instead, it promoted the release of hematopoietic cytokines, including interleukin 6 from bone marrow mesenchymal stromal cells (MSCs) in the hematopoietic stem cell niche, which in turn reduced the expression of the transcription factors Runx-1 and Cebpα in early hematopoietic progenitor cells and increased myeloid differentiation. Therefore, our study indicates that, during an acute viral infection, CTLs indirectly modulate early multipotent hematopoietic progenitors via MSCs in order to trigger the temporary activation of emergency myelopoiesis and promote clearance of the infection.

Neutrophil expression of ICAM1, CXCR1, and VEGFR1 in patients with breast cancer before and after adjuvant chemotherapy

BACKGROUND Distinct populations of neutrophils have been identified based on the expression of intercellular adhesion molecule 1 (ICAM1, CD54) and chemokine receptor 1 (CXCR1, interleukin 8 receptor α). AIM We analyzed the expression of vascular endothelial growth factor receptor 1 (VEGFR1), a physiological negative regulator of angiogenesis, on distinct populations of neutrophils from the blood of patients before and after adjuvant chemotherapy for breast cancer. MATERIALS AND METHODS Neutrophil populations were distinguished as reverse transmigrated (ICAM1(high)/CXCR1(low)), naïve (ICAM1(low)/CXCR1(high)), or tissue-resident neutrophils (ICAM1(low)/CXCR1(low)), and their VEGFR1 expression quantified. RESULTS Reverse transmigrated ICAM1(high)/CXCR1(low) neutrophilic granulocytes decreased significantly after chemotherapy and these were also the cells with highest mean fluorescence intensity for VEGFR1. CONCLUSION Chemotherapy mainly reduces the number of reverse transmigrated long-lived ICAM1(high)/CXCR1(low) VEGFR1-expressing neutrophils. The decrease of antiangiogenic VEGFR1 may have a potential impact on tumour angiogenesis in patients undergoing adjuvant chemotherapy.

Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand on NK Cells Protects From Hepatic Ischemia-Reperfusion Injury

BACKGROUND: Ischemia-reperfusion injury (IRI) significantly contributes to graft dysfunction after liver transplantation. Natural killer (NK) cells are crucial innate effector cells in the liver and express tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a potent inducer of hepatocyte cell death. Here, we investigated if TRAIL expression on NK cells contributes to hepatic IRI. METHODS: The outcome after partial hepatic IRI was assessed in TRAIL-null mice and contrasted to C57BL/6J wild-type mice and after NK cell adoptive transfer in RAG2/common gamma-null mice that lack T, B, and NK cells. Liver IRI was assessed by histological analysis, alanine aminotransferase, hepatic neutrophil activation by myeloperoxidase activity, and cytokine secretion at specific time points. NK cell cytotoxicity and differentiation were assessed in vivo and in vitro. RESULTS: Twenty-four hours after reperfusion, TRAIL-null mice exhibited significantly higher serum transaminases, histological signs of necrosis, neutrophil infiltration, and serum levels of interleukin-6 compared to wild-type animals. Adoptive transfer of TRAIL-null NK cells into immunodeficient RAG2/common gamma-null mice was associated with significantly elevated liver damage compared to transfer of wild-type NK cells. In TRAIL-null mice, NK cells exhibit higher cytotoxicity and decreased differentiation compared to wild-type mice. In vitro, cytotoxicity against YAC-1 and secretion of interferon gamma by TRAIL-null NK cells were significantly increased compared to wild-type controls. CONCLUSIONS: These experiments reveal that expression of TRAIL on NK cells is protective in a murine model of hepatic IRI through modulation of NK cell cytotoxicity and NK cell differentiation.

Pre-therapy inflammation and coagulation activation and long-term CD4 count responses to the initiation of antiretroviral therapy

OBJECTIVES Pre-antiretroviral therapy (ART) inflammation and coagulation activation predict clinical outcomes in HIV-positive individuals. We assessed whether pre-ART inflammatory marker levels predicted the CD4 count response to ART. METHODS Analyses were based on data from the Strategic Management of Antiretroviral Therapy (SMART) trial, an international trial evaluating continuous vs. interrupted ART, and the Flexible Initial Retrovirus Suppressive Therapies (FIRST) trial, evaluating three first-line ART regimens with at least two drug classes. For this analysis, participants had to be ART-naïve or off ART at randomization and (re)starting ART and have C-reactive protein (CRP), interleukin-6 (IL-6) and D-dimer measured pre-ART. Using random effects linear models, we assessed the association between each of the biomarker levels, categorized as quartiles, and change in CD4 count from ART initiation to 24 months post-ART. Analyses adjusted for CD4 count at ART initiation (baseline), study arm, follow-up time and other known confounders. RESULTS Overall, 1084 individuals [659 from SMART (26% ART naïve) and 425 from FIRST] met the eligibility criteria, providing 8264 CD4 count measurements. Seventy-five per cent of individuals were male with the mean age of 42 years. The median (interquartile range) baseline CD4 counts were 416 (350-530) and 100 (22-300) cells/μL in SMART and FIRST, respectively. All of the biomarkers were inversely associated with baseline CD4 count in FIRST but not in SMART. In adjusted models, there was no clear relationship between changing biomarker levels and mean change in CD4 count post-ART (P for trend: CRP, P = 0.97; IL-6, P = 0.25; and D-dimer, P = 0.29). CONCLUSIONS Pre-ART inflammation and coagulation activation do not predict CD4 count response to ART and appear to influence the risk of clinical outcomes through other mechanisms than blunting long-term CD4 count gain.

Molecular characterization and SNP development for the porcine IL6 and IL10 genes

Different cytokines are secreted in response to specific microbial molecules referred to as pathogen associated molecular patterns (PAMPs). Interleukin 6 (IL6) and interleukin 10 (IL10), both secreted by macrophages and lymphocytes, play a central role in the immunological response. In this work we obtained the genomic structure and complete DNA sequence of the porcine IL6 and IL10 genes and identified polymorphisms in the genomic sequences of these genes on a panel of ten different pig breeds. Comparative intra- and interbreed sequence analysis revealed a total of eight polymorphisms in the porcine IL6 gene and 21 in the porcine IL10 gene, which include single nucleotide polymorphisms (SNPs) and insertion deletion polymorphisms (indels). Additionally, the chromosomal localization of the IL10 gene was determined by FISH and RH mapping.

Parasite-mediated nuclear factor kappaB regulation in lymphoproliferation caused by Theileria parva infection.

Infection of cattle with the protozoan Theileria parva results in uncontrolled T lymphocyte proliferation resulting in lesions resembling multicentric lymphoma. Parasitized cells exhibit autocrine growth characterized by persistent translocation of the transcriptional regulatory factor nuclear factor kappaB (NFkappaB) to the nucleus and consequent enhanced expression of interleukin 2 and the interleukin 2 receptor. How T. parva induces persistent NFkappaB activation, required for T cell activation and proliferation, is unknown. We hypothesized that the parasite induces degradation of the IkappaB molecules which normally sequester NFkappaB in the cytoplasm and that continuous degradation requires viable parasites. Using T. parva-infected T cells, we showed that the parasite mediates continuous phosphorylation and proteolysis of IkappaBalpha. However, IkappaBalpha reaccumulated to high levels in parasitized cells, which indicated that T. parva did not alter the normal NFkappaB-mediated positive feedback loop which restores cytoplasmic IkappaBalpha. In contrast, T. parva mediated continuous degradation of IkappaBbeta resulting in persistently low cytoplasmic IkappaBbeta levels. Normal IkappaBbeta levels were only restored following T. parva killing, indicating that viable parasites are required for IkappaBbeta degradation. Treatment of T. parva-infected cells with pyrrolidine dithiocarbamate, a metal chelator, blocked both IkappaB degradation and consequent enhanced expression of NFkappaB dependent genes. However treatment using the antioxidant N-acetylcysteine had no effect on either IkappaB levels or NFkappaB activation, indicating that the parasite subverts the normal IkappaB regulatory pathway downstream of the requirement for reactive oxygen intermediates. Identification of the critical points regulated by T. parva may provide new approaches for disease control as well as increase our understanding of normal T cell function.

C-C chemokine receptor 6-regulated entry of TH-17 cells into the CNS through the choroid plexus is required for the initiation of EAE

Interleukin 17-producing T helper cells (T(H)-17 cells) are important in experimental autoimmune encephalomyelitis, but their route of entry into the central nervous system (CNS) and their contribution relative to that of other effector T cells remain to be determined. Here we found that mice lacking CCR6, a chemokine receptor characteristic of T(H)-17 cells, developed T(H)-17 responses but were highly resistant to the induction of experimental autoimmune encephalomyelitis. Disease susceptibility was reconstituted by transfer of wild-type T cells that entered into the CNS before disease onset and triggered massive CCR6-independent recruitment of effector T cells across activated parenchymal vessels. The CCR6 ligand CCL20 was constitutively expressed in epithelial cells of choroid plexus in mice and humans. Our results identify distinct molecular requirements and ports of lymphocyte entry into uninflamed versus inflamed CNS and suggest that the CCR6-CCL20 axis in the choroid plexus controls immune surveillance of the CNS.

Dose-response effect of interleukin (IL)-1beta, tumour necrosis factor (TNF)-alpha, and interferon-y on the in vitro production of epithelial neutrophil activating peptide-78 (ENA-78), IL-8, and IL-6 by human endometrial stromal cells

The production of epithelial neutrophil activating peptide-78 (NA-78) and the interleukins IL-8 and IL-6 by endometrial stromal cells is stimulated by pro-inflammatory interleukin-1 (IL-1) and tumour necrosis factor-α (TNF-α). IL-8 is suggested to play a role in the pathogenesis of endometriosis, and in these women the peritoneal fluid concentrations of ENA-78 and IL-8 are increased. TNF-α has been tested together with interferon-γ because of their cooperative stimulation of IL-6. The release of IL-8, however, is inhibited with increasing interferon levels. The aim of the study was the analysis of the production of ENA-78, IL-6 and IL-8 by cultured human endometrial stromal cells in the presence of varying concentrations of IL-1β, TNF-α, and interferon-γ.