Rheumatoid arthritis progression mediated by activated synovial fibroblasts

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial hyperplasia and progressive joint destruction. Rheumatoid arthritis synovial fibroblasts (RASFs) are leading cells in joint erosion and contribute actively to inflammation. RASFs show an activated phenotype that is independent of the inflammatory environment and requires the combination of several factors. Although new aspects regarding RASF activation via matrix degradation products, epigenetic modifications, inflammatory factors, Toll-like receptor (TLR) activation and others have recently been uncovered, the primary pathophysiological processes in early arthritis leading to permanent activation are mostly unknown. Here, we review new findings regarding RASF activation and their altered behavior that contribute to matrix destruction and inflammation as well as their potential to spread RA.

Very low oxygen concentration (0.1%) reveals two FDCP-Mix cell subpopulations that differ by their cell cycling, differentiation and p27KIP1 expression

Oxygen (O(2)) concentrations in bone marrow vary from 4% in capillaries to <0.1% in subendosteum, in which hematopoietic stem cells reside in specific niches. Culture at low O(2) concentrations (3, 1 and 0.1%) influences hematopoietic stem and progenitor cells survival, proliferation and differentiation, depending on their level of differentiation. Culture of human CD34(+) cells at low O(2) concentrations (O(2) ≤3%) maintains stem cell engraftment potential better than at 20% O(2) (NOD/Scid xenograft model). In contrast, progenitors disappear from cultures at/or <1% O(2) concentrations. A very low O(2) concentration (0.1%) induces CD34(+) quiescence in G(0). The exploration of molecules and mechanisms involved in hematopoietic stem and progenitor cells' quiescence and differentiation related to low O(2) concentrations is unfeasible with primary CD34(+) cells. Therefore, we performed it using murine hematopoietic nonleukemic factor-dependent cell Paterson (FDCP)-Mix progenitor cell line. The culture of the FDCP-Mix line at 0.1% O(2) induced in parallel G(0) quiescence and granulo-monocytic differentiation of most cells, whereas a minority of undifferentiated self-renewing cells remained in active cell cycle. Hypoxia also induced hypophosphorylation of pRb and increased the expression of p27(KIP1), the two proteins that have a major role in the control of G(0) and G(1) to S-phase transition.

Role of CX3CR1/CX3CL1 axis in primary and secondary involvement of the nervous system by cancer

CX3CL1 or Fractalkine is a peculiar chemokine that can exist either in a soluble form, like all the other chemokines, and as a cell membrane molecule. CX3CL1 is one of the most expressed chemokines in the central nervous system, where it regulates the communication between neurons, glia and microglia. CX3CR1-expressing microglia may have an important role in limiting tissue injury during inflammation and neuro-degeneration. Recent evidence has implicated CX3CL1 and its cognate receptor CX3CR1 in cancer. Tumors of neural origin (glioma, neuroblastoma) express CX3CR1 which is involved in the adhesion, transendothelial migration and mobilization of tumor cells. In addition, tumors of non-neural origin, like prostate, pancreas and breast carcinoma express high levels of the CX3CR1 receptor. As for other chemokine receptors, CX3CR1 expression is associated with increased migration and site specific dissemination. In pancreatic cancer, receptor expression is involved in the perineural invasion and dissemination of neoplastic cells along intra- and extra-pancreatic nerves. This peculiar route of tumor spread is used also by other carcinomas (e.g. prostate, head and neck) and may represent a target for therapeutic intervention.

CXC chemokines in cancer angiogenesis and metastases

The tumor microenvironment is extremely complex that depends on tumor cell interaction with the responding host cells. Angiogenesis, or new blood vessel growth from preexisting vasculature, is a preeminent feature of successful tumor growth of all solid tumors. While a number of factors produced by both the tumor cells and host responding cells have been discovered that regulate angiogenesis, increasing evidence is growing to support the important role of CXC chemokines in this process. As a family of cytokines, the CXC chemokines are pleiotropic in their ability to regulate tumor-associated angiogenesis, as well as cancer cell metastases. In this chapter, we will discuss the disparate activity that CXC chemokines play in regulating cancer-associated angiogenesis and metastases.

Characterization of the novel ST2/IL-33 system in patients with inflammatory bowel disease

BACKGROUND

ST2 has been proposed to be a regulator of inflammation and Th1/Th2 balance. ST2L is the IL-33 membrane receptor and belongs to the IL-1R family. The soluble variant, ST2s, is identical to the extracellular region of ST2L and competes for IL-33 binding, inhibiting receptor signaling. Although ST2s has been associated with inflammatory processes in patients with sepsis, trauma, asthma, and autoimmunity, until now there are no reported studies showing the role of ST2/IL-33 in inflammatory bowel disease (IBD).

METHODS

Expression of ST2 and IL-33 was determined in serum and colonic biopsies from IBD patients. ST2 transcript and protein was determined by reverse-transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA)/immunoblot, respectively, and IL-33 protein by ELISA. Intestinal mucosa localization of ST2 and IL-33 was conducted by immunofluorescence.

RESULTS

ST2s transcript in the colonic mucosa was mainly expressed in UC patients rather than Crohn's disease or control; however, ST2L mRNA remained constant in all samples. Total ST2 protein was significantly higher in mucosa samples from patients with active UC, with a predominant induction of ST2s that strongly correlates with serum ST2 levels. Mucosa IL-33 levels were higher in UC patients and serum levels were barely detected in all patient groups. ST2 and IL-33 are both abundantly expressed in the cytoplasm of epithelial cells of control subjects; however, in ulcerative colitis patients ST2 decreases and IL-33 showed cytoplasm-nuclear redistribution.

CONCLUSIONS

The novel association between the ST2/IL-33 system and IBD seems to identify that variations in this axis might regulate the inflammatory process in these diseases.

Whole blood cytokine attenuation by cholinergic agonists ex vivo and relationship to vagus nerve activity in rheumatoid arthritis

OBJECTIVE

The central nervous system regulates innate immunity in part via the cholinergic anti-inflammatory pathway, a neural circuit that transmits signals in the vagus nerve that suppress pro-inflammatory cytokine production by an alpha-7 nicotinic acetylcholine receptors (alpha7nAChR) dependent mechanism. Vagus nerve activity is significantly suppressed in patients with autoimmune diseases, including rheumatoid arthritis (RA). It has been suggested that stimulating the cholinergic anti-inflammatory pathway may be beneficial to patients, but it remains theoretically possible that chronic deficiencies in this pathway will render these approaches ineffective.

METHODS

Here we addressed the hypothesis that inflammatory cells from RA patients can respond to cholinergic agonists with reduced cytokine production in the setting of reduced vagus nerve activity.

RESULTS

Measurement of RR interval variability (heart rate variability, HRV), in RA patients (n = 13) and healthy controls (n = 10) revealed that vagus nerve activity was significantly depressed in patients. Whole blood cultures stimulated by exposure to endotoxin produced significantly less tumour necrosis factor in samples from RA patients as compared to healthy controls. Addition of cholinergic agonists (nicotine and GTS-21) to the stimulated whole blood cultures however significantly suppressed cytokine production to a similar extent in patients and healthy controls.

CONCLUSION

These findings suggest that it is possible to pharmacologically target the alpha7nAChR dependent control of cytokine release in RA patients with suppressed vagus nerve activity. As alpha7nAChR agonists ameliorate the clinical course of collagen induced arthritis in animals, it may be possible in the future to explore whether alpha7nAChR agonists can improve clinical activity in RA patients.

Intravenous ibuprofen (IV-ibuprofen) controls fever effectively in adults with acute uncomplicated Plasmodium falciparum malaria but prolongs parasitemia

Because some febrile patients are unable to swallow or retain oral antipyretic drugs, we carried out a double-blind, placebo-controlled trial in which intravenous ibuprofen (IV-ibuprofen) was given to adults hospitalized with fever associated with acute uncomplicated falciparum malaria treated with oral artesunate plus mefloquine. Thirty patients received IV-ibuprofen 400 mg and 30 received placebo every 6 hours for 72 hours. Reduction in the area above 37.0 degrees C versus time curve was significantly greater for IV-ibuprofen than for placebo during the first 72 hours after first administration. No patients developed severe malaria; parasite clearance was delayed in the patients whose fevers were controlled by IV-ibuprofen (median 37.3 hours versus 23.7 hours in the placebo group [P = 0.0024]). This difference did not appear to be clinically important Adverse events, none considered severe, occurred equally in both groups. IV-ibuprofen was effective and well tolerated in reducing fever in febrile inpatients with malaria.

Assessing the human immune system through blood transcriptomics

Blood is the pipeline of the immune system. Assessing changes in transcript abundance in blood on a genome-wide scale affords a comprehensive view of the status of the immune system in health and disease. This review summarizes the work that has used this approach to identify therapeutic targets and biomarker signatures in the field of autoimmunity and infectious disease. Recent technological and methodological advances that will carry the blood transcriptome research field forward are also discussed.

Inoculated mammary carcinoma-associated fibroblasts: contribution to hormone independent tumor growth

Background

Increasing evidence has underscored the role of carcinoma associated fibroblasts (CAF) in tumor growth. However, there are controversial data regarding the persistence of inoculated CAF within the tumors. We have developed a model in which murine metastatic ductal mammary carcinomas expressing estrogen and progesterone receptors transit through different stages of hormone dependency. Hormone dependent (HD) tumors grow only in the presence of progestins, whereas hormone independent (HI) variants grow without hormone supply. We demonstrated previously that CAF from HI tumors (CAF-HI) express high levels of FGF-2 and that FGF-2 induced HD tumor growth in vivo. Our main goal was to investigate whether inoculated CAF-HI combined with purified epithelial (EPI) HD cells can induce HD tumor growth.

Methods

Purified EPI cells of HD and HI tumors were inoculated alone, or together with CAF-HI, into female BALB/c mice and tumor growth was evaluated. In another set of experiments, purified EPI-HI alone or combined with CAF-HI or CAF-HI-GFP were inoculated into BALB/c or BALB/c-GFP mice. We assessed whether inoculated CAF-HI persisted within the tumors by analyzing inoculated or host CAF in frozen sections of tumors growing in BALB/c or BALB/c-GFP mice. The same model was used to evaluate early stages of tumor development and animals were euthanized at 2, 7, 12 and 17 days after EPI-HI or EPI-HI+CAF-HI inoculation. In angiogenesis studies, tumor vessels were quantified 5 days after intradermal inoculation.

Results

We found that admixed CAF-HI failed to induce epithelial HD tumor growth, but instead, enhanced HI tumor growth (p < 0.001). Moreover, inoculated CAF-HI did not persist within the tumors. Immunofluorescence studies showed that inoculated CAF-HI disappeared after 13 days. We studied the mechanisms by which CAF-HI increased HI tumor growth, and found a significant increase in angiogenesis (p < 0.05) in the co-injected mice at early time points.

Conclusions

Inoculated CAF-HI do not persist within the tumor mass although they play a role during the first stages of tumor formation promoting angiogenesis. This angiogenic environment is unable to replace the hormone requirement of HD tumors that still need the hormone to recruit the stroma from the host.

Slow-cycling/quiescence balance of hematopoietic stem cells is related to physiological gradient of oxygen

OBJECTIVE

Regulation of hematopoiesis depends on cytokines, cellular interactions, transcription, and metabolic factors. Among the latter, O(2) has been neglected for a long time. Recently, an increasing number of publications evidenced the regulatory role of physiological low O(2) concentrations (0.1-5%; similar to those in bone marrow) on the in vitro behavior of hematopoietic stem cells. This brief review utilizes the article of Eliasson and colleagues in this Journal to summarize the major results and questions about the relationships between O(2) and hematopoiesis.

MATERIALS AND METHODS

In order to be concise and interesting for readers unfamiliar with this field, we selected only the most significant data that either reinforce or contradict the conclusions of Eliasson et al., but we also provide references of reviews with a more detailed bibliography.

RESULTS

A critical analysis of some key publications provides partial answers to three important questions: is the term hypoxia appropriate to describe physiological low O(2) concentrations? Is a very low O(2) level sufficient to control the quiescence/slow cycling balance of hematopoietic stem cells? Is the O(2) concentration able to modify the effect of cytokines on hematopoietic stem cells?

CONCLUSIONS

We propose to use in situ normoxia instead of the confusing term hypoxia when working with normal cells at physiological low O(2) concentrations. We suggest that a very low O(2) concentration is necessary but not sufficient to induce hematopoietic stem cell quiescence. We review some articles showing that O(2) variations modify the effect of cytokines.

The paracrine effect: pivotal mechanism in cell-based cardiac repair

Cardiac cell therapy has emerged as a controversial yet promising therapeutic strategy. Both experimental data and clinical applications in this field have shown modest but tangible benefits on cardiac structure and function and underscore that transplanted stem-progenitor cells can attenuate the postinfarct microenvironment. The paracrine factors secreted by these cells represent a pivotal mechanism underlying the benefits of cell-mediated cardiac repair. This article reviews key studies behind the paracrine effect related to the cardiac reparative effects of cardiac cell therapy.

The role of angiogenic factors in predicting clinical outcome in severe bacterial infection in Malawian children

Introduction

Severe sepsis is a disease of the microcirculation, with endothelial dysfunction playing a key role in its pathogenesis and subsequent associated mortality. Angiogenesis in damaged small vessels may ameliorate this dysfunction. The aim of the study was to determine whether the angiogenic factors (vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), and angiopoietin-1 (Ang-1) and -2 (Ang-2)) are mortality indicators in Malawian children with severe bacterial infection.

Methods

In 293 children with severe bacterial infection, plasma VEGF, PDGF, FGF, and Ang-1 and Ang-2 were measured on admission; in 50 of the children with meningitis, VEGF, PDGF, and FGF were also measured in the CSF. Healthy controls comprised children from some of the villages of the index cases. Univariable and multivariable logistic regression analyses were performed to develop a prognostic model.

Results

The median age was 2.4 years, and the IQR, 0.7 to 6.0 years. There were 211 children with bacterial meningitis (72%) and 82 (28%) with pneumonia, and 154 (53%) children were HIV infected. Mean VEGF, PDGF, and FGF concentrations were higher in survivors than in nonsurvivors, but only PDGF remained significantly increased in multivariate analysis (P = 0.007). Mean Ang-1 was significantly increased, and Ang-2 was significantly decreased in survivors compared with nonsurvivors (6,000 versus 3,900 pg/ml, P = 0.03; and 7,700 versus 11,900 pg/ml, P = 0.02, respectively). With a logistic regression model and controlling for confounding factors, only female sex (OR, 3.95; 95% CI, 1.33 to 11.76) and low Ang-1 (OR, 0.23; 95% CI, 0.08 to 0.69) were significantly associated with mortality. In children with bacterial meningitis, mean CSF VEGF, PDGF, and FGF concentrations were higher than paired plasma concentrations, and mean CSF, VEGF, and FGF concentrations were higher in nonsurvivors than in survivors (P = 0.02 and 0.001, respectively).

Conclusions

Lower plasma VEGF, PDGF, FGF, and Ang-1 concentrations and higher Ang-2 concentrations are associated with an unfavorable outcome in children with severe bacterial infection. These angiogenic factors may be important in the endothelial dysregulation seen in severe bacterial infection, and they could be used as biomarkers for the early identification of patients at risk of a poor outcome.

How tumour necrosis factor blockers interfere with tuberculosis immunity

Tumour necrosis factor (TNF) is a potent inflammatory cytokine that plays an important role in immunity to numerous bacterial infections, including Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB) in humans. Infliximab, adalimumab, certolizumab pegol and etanercept are anti-TNF agents used to treat a range of inflammatory/autoimmune diseases, such as rheumatoid arthritis. The use of some of these drugs has been linked to reactivation TB. In addition to blocking TNF-mediated immune responses, some anti-TNF drugs have been found to interfere with innate immune responses, such as phagolysosomal maturation and monocyte apoptosis, as well as cell-mediated responses, including interferon-gamma secretion by memory T cells, complement-mediated lysis of Mtb-reactive CD8+ T cells and increased regulatory T cell activity. This review summarizes some of the reported effects of TNF blockers on immune cell responses in the context of the observed clinical data on TB reactivation in patients on anti-TNF therapy.

The use of machine learning and nonlinear statistical tools for ADME prediction

Absorption, distribution, metabolism and excretion (ADME)-related failure of drug candidates is a major issue for the pharmaceutical industry today. Prediction of ADME by in silico tools has now become an inevitable paradigm to reduce cost and enhance efficiency in pharmaceutical research. Recently, machine learning as well as nonlinear statistical tools has been widely applied to predict routine ADME end points. To achieve accurate and reliable predictions, it would be a prerequisite to understand the concepts, mechanisms and limitations of these tools. Here, we have devised a small synthetic nonlinear data set to help understand the mechanism of machine learning by 2D-visualisation. We applied six new machine learning methods to four different data sets. The methods include Naive Bayes classifier, classification and regression tree, random forest, Gaussian process, support vector machine and k nearest neighbour. The results demonstrated that ensemble learning and kernel machine displayed greater accuracy of prediction than classical methods irrespective of the data set size. The importance of interaction with the engineering field is also addressed. The results described here provide insights into the mechanism of machine learning, which will enable appropriate usage in the future.

Mediators of ocular angiogenesis

Angiogenesis is the formation of new blood vessels from pre-existing vasculature. Pathologic angiogenesis in the eye can lead to severe visual impairment. In our review, we discuss the roles of both pro-angiogenic and anti-angiogenic molecular players in corneal angiogenesis, proliferative diabetic retinopathy, exudative macular degeneration and retinopathy of prematurity, highlighting novel targets that have emerged over the past decade.

Polymorphisms in tumour necrosis factor alpha (TNFalpha) gene in patients with acute pancreatitis

Proinflammatory cytokines, such as tumour necrosis factor α (TNFα), play fundamental roles in the pathogenesis of acute pancreatitis (AP). The aim of this study was to determine if polymorphisms in the TNFα gene are associated with AP. Two polymorphisms located in the promoter region (positions −308 and −238) in TNFα gene were determined using polymerase chain reaction- (PCR-) restriction fragment length polymorphism (RFLP) methods in 103 patients with AP and 92 healthy controls. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using logistic regression analysis adjusted for age, sex, BMI and smoking. The frequencies of TNFα polymorphisms were both similar in patients with mild or severe pancreatitis, so were in pancreatitis patients and in controls. We suggest that both SNPs of TNFα are not genetic risk factor for AP susceptibility (OR = 1.63; 95% CI: 1.13−4.01 for TNFα⁻³⁰⁸ and OR = 0.86; 95% CI: 0.75−1.77 for TNFα⁻²³⁸).

Interplay of host and infectious agents

In this group we would like to answer the question why people show a different response against certain pathogens. In many infections the course of the disease can range from asymptomatic carriage to the severest forms even death. In the past we have analysed candidate genes and their role in the course of malaria and could detect some polymorphisms influencing infectious diseases in the genes encoding NOS2, MBL2, IFNa, FCN2, and receptors for IFNg and IFNa. Having worked initially mainly on malaria we broadened our spectrum also to other infectious diseases like hepatitis B, Leprosy, schistosomiasis. Here we give a short overview about ongoing projects.

Functional genomics of endothelial cells treated with anti-angiogenic or angiopreventive drugs

Angiogenesis is a highly regulated physiological process that has been studied in considerable detail given its importance in several chronic pathologies. Many endogenous factors and hormones intervene in the regulation of angiogensis and classical as well as targeted drugs have been developed for its control. Angiogenesis inhibition has come off the bench and entered into clinical application for cancer therapy, particularly for metastatic disease. While the clinical benefit is currently in terms of months, preclinical data suggest that novel drugs and drug combinations could lead to substantial improvement. The many targets of endogenous angiogenesis inhibitors reflect the complexity of the process; in contrast, current clinical therapies mainly target the vascular endothelial growth factor system. Cancer chemopreventive compounds can retard tumor insurgence and delay or prevent metastasis and many of these molecules hinder angiogenesis, a mechanism that we termed angioprevention. Angiopreventive drugs appear to prevalently act through the inhibition of the pro-inflammatory and anti-apoptotic player NFkappaB, thus contrasting inflammation dependent angiogenesis. Relatively little is known concerning the effects of these angiogenesis inhibitors on gene expression of endothelial cells, the main target of many of these molecules. Here we provide an exhaustive list of anti-angiogenic molecules, and summarize their effects, where known, on the transcriptome and functional genomics of endothelial cells. The regulation of specific genes can be crucial to preventive or therapeutic intervention. Further, novel targets might help to circumvent resistance to anti-angiogenic therapy. The studies we review are relevant not only to cancer but also to other chronic degenerative diseases involving endothelial cells, such as cardiovascular disorders, diabetes, rheumatoid arthritis and retinopaties, as well as vessel aging.

Respiratory syncytial virus F and G proteins induce interleukin 1alpha, CC, and CXC chemokine responses by normal human bronchoepithelial cells

Human respiratory syncytial virus (RSV) is a ubiquitous respiratory virus that causes serious lower respiratory tract disease in infants and young children worldwide. Studies have shown that RSV infection modulates chemokine expression patterns, suggesting that particular cytokine expression profiles may be indicators of disease severity. In this study, we show that RSV F or G protein treatment of fully differentiated primary normal human bronchial epithelial cells induces apical and basolateral secretion of interleukin 8 (IL-8), interferon-inducible protein 10 (IP-10), monocyte chemotactic protein 1 (MCP-1), and RANTES (regulated on activation, normal T cell expressed and secreted). Purified RSV G (attachment) protein was shown to stimulate the secretion of interleukin 1alpha and RANTES, whereas purified F (fusion) protein elicited the production of IL-8, IP-10, and RANTES. Studies of ultraviolet-inactivated RSV showed that treatment of normal human bronchial epithelial cells induces apical IL-8, IP-10, and MCP-1 secretion independent of infection, suggesting that RSV proteins alone modify the chemokine response pattern, which may affect the early immune response before infection.

Development of a multimarker assay for early detection of ovarian cancer

PURPOSE

Early detection of ovarian cancer has great promise to improve clinical outcome.

PATIENTS AND METHODS

Ninety-six serum biomarkers were analyzed in sera from healthy women and from patients with ovarian cancer, benign pelvic tumors, and breast, colorectal, and lung cancers, using multiplex xMAP bead-based immunoassays. A Metropolis algorithm with Monte Carlo simulation (MMC) was used for analysis of the data.

RESULTS

A training set, including sera from 139 patients with early-stage ovarian cancer, 149 patients with late-stage ovarian cancer, and 1,102 healthy women, was analyzed with MMC algorithm and cross validation to identify an optimal biomarker panel discriminating early-stage cancer from healthy controls. The four-biomarker panel providing the highest diagnostic power of 86% sensitivity (SN) for early-stage and 93% SN for late-stage ovarian cancer at 98% specificity (SP) was comprised of CA-125, HE4, CEA, and VCAM-1. This model was applied to an independent blinded validation set consisting of sera from 44 patients with early-stage ovarian cancer, 124 patients with late-stage ovarian cancer, and 929 healthy women, providing unbiased estimates of 86% SN for stage I and II and 95% SN for stage III and IV disease at 98% SP. This panel was selective for ovarian cancer showing SN of 33% for benign pelvic disease, SN of 6% for breast cancer, SN of 0% for colorectal cancer, and SN of 36% for lung cancer.

CONCLUSION

A panel of CA-125, HE4, CEA, and VCAM-1, after additional validation, could serve as an initial stage in a screening strategy for epithelial ovarian cancer.

Reproducibility of plasma and urine biomarkers among premenopausal and postmenopausal women from the Nurses' Health Studies

BACKGROUND

Temporal variability of biomarkers should be evaluated before their use in epidemiologic studies.

METHODS

We evaluated the reproducibility, using intraclass correlation coefficients (ICC), of 77 plasma and 9 urinary biomarkers over 1 to 3 years among premenopausal (n = 40) and postmenopausal (n = 35-70) participants from the Nurses' Health Study and Nurses' Health Study II.

RESULTS

Plasma and urinary stress hormones and melatonin were measured among premenopausal women, whereas melatonin and the remaining biomarkers were measured in postmenopausal women. ICCs were good to excellent for plasma carotenoids (0.73-0.88), vitamin D analytes (0.56-0.72), bioactive somatolactogens (0.62), soluble leptin receptor (0.82), resistin (0.74), and postmenopausal melatonin (0.63). Reproducibility was lower for some of the plasma fatty acids (0.38-0.72), matrix metalloproteinases (0.07-0.91), and premenopausal melatonin (0.44). The ICCs for plasma and urinary phytoestrogens were poor (< or = 0.09) except for enterolactone (plasma, 0.44; urinary, 0.52). ICCs for the stress hormones among premenopausal women ranged from 0 (plasma cortisol) to 0.45 (urinary dopamine).

CONCLUSIONS

Our results indicate that for the majority of these markers, a single measurement can reliably estimate average levels over a 1- to 3-year period in epidemiologic studies. For analytes with fair to good ICCs, reproducibility data can be used for measurement error correction. Analytes with poor ICCs should only be used in settings with multiple samples per subject or in populations in which ICCs are higher.

IMPACT

This article summarizes the feasibility of the use of >80 biomarkers in epidemiologic studies in which only one biospecimen is available to represent longer term exposure.

Increased Serum PAI-1 Levels in Subjects with Metabolic Syndrome and Long-Term Adverse Mental Symptoms: A Population-Based Study

Depression is an independent risk factor for cardiovascular diseases and is associated with metabolic syndrome (MetS). Levels of plasminogen activator inhibitor-1 (PAI-1), an inhibitor of tissue-type and urokinase-type plasminogen activators, are associated with MetS. To clarify the role of PAI-1 in subjects with long-term adverse mental symptomatology (LMS; including depression) and MetS, we measured circulating PAI-1 levels in controls (n = 111), in subjects with MetS and free of mental symptoms (n = 42), and in subjects with both MetS and long-term mental symptoms (n = 70). PAI-1 increased linearly across the three groups in men. In logistic regression analysis, men with PAI-1 levels above the median had a 3.4-fold increased likelihood of suffering from the comorbidity of long-term adverse mental symptoms and MetS, while no such associations were detected in women. In conclusion, our results suggest that in men high PAI-1 levels are independently associated with long-term mental symptomatology.

Cytokine protein expression levels in tracheobronchial lymph node homogenates of pigs infected with pseudorabies virus

Pseudorabies virus (PRV) is a neurotropic alphaherpesvirus that produces fatal encephalitis in newborn pigs, respiratory disorders in fattening pigs, and reproductive failure in sows. Following primary infection of the respiratory tract, PRV can develop into a systemic infection with dispersion of the virus via the lymphatic system that involves mononuclear cells in tracheobronchial lymph nodes (TBLNs). The objectives of the present study were to evaluate the pathogenesis and to determine the early immune cytokine profiles in TBLNs following experimental infection with a feral swine PRV isolate at 1, 3, 6, and 14 days postinfection (dpi). Forty healthy pigs were purchased from a PRV-negative herd. Twenty pigs received the Florida strain isolate (FS268) of feral swine PRV intranasally, and 20 uninfected controls received a sham inoculum. Compared to the levels in the controls, the levels of alpha interferon (IFN-alpha), interleukin-1beta (IL-1beta), IL-12, and IFN-gamma were increased in TBLN homogenates from PRV-infected pigs at 1 dpi, whereas the IL-18 levels were decreased from 3 to 6 dpi. The protein levels of IL-4 and IL-10 did not differ between the controls and the PRV-infected pigs at any time point. Flow cytometric analysis of TBLN homogenates of PRV-infected pigs and the controls revealed increases in the percentages of B cells at 6 dpi, CD4(+) cells at 14 dpi, and CD25 expression in TBLN homogenates (in the total mononuclear fraction and on B cells) in the PRV-infected pigs. Collectively, these findings demonstrate that a feral PRV in commercial swine can modulate the host's early immune response to allow the virus to establish an infection.

Blockade of interleukin 1 in type 1 diabetes mellitus

Interleukin 1 (IL-1) is a 17 kDa protein highly conserved through evolution and is a key mediator of inflammation, fever and the acute-phase response. IL-1 has important functions in the innate immune defense against microbes, trauma and stress, and is also an effector molecule involved in tissue destruction and fibrosis. The inhibition of IL-1 action has clinical efficacy in many inflammatory diseases, such as hereditary autoinflammatory disorders, familial hereditary fever, gout, rheumatoid arthritis and type 2 diabetes mellitus (T2DM). The latter is a common metabolic condition caused by insulin resistance and pancreatic beta-cell failure, the causes of both of which have inflammatory components. IL-1 signaling has roles in beta-cell dysfunction and destruction via the NFkappaB and mitogen-activated-protein-kinase pathways, leading to endoplasmic reticulum and mitochondrial stress and eventually activating the apoptotic machinery. In addition, IL-1 acts on T-lymphocyte regulation. The modulating effect of IL-1 on the interaction between the innate and adaptive immune systems and the effects of IL-1 on the beta-cell point to this molecule being a potential interventional target in autoimmune diabetes mellitus. Genetic or pharmacological abrogation of IL-1 action reduces disease incidence in animal models of type 1 diabetes mellitus (T1DM) and clinical trials have been started to study the feasibility, safety and efficacy of IL-1 therapy in patients with T1DM. Here, we review the rationale for blocking IL-1 in patients with T1DM.

Prognostic significance of genetic variants in the IL-23/Th17 pathway for the outcome of T cell-depleted allogeneic stem cell transplantation

T helper (Th) 17 cells have emerged as important mediators in infectious and inflammatory diseases and, recently, in transplant rejection. We analyzed the associations between five common genetic variants in the IL-23/Th17 signaling pathway, namely in IL17A, IL17F and IL23R genes, and clinical outcome in T cell-depleted allogeneic SCT (allo-SCT). In the multivariate analysis, variants in IL23R and IL17A genes were the most important prognostic factors. Thus, patient GA genotype at rs11209026 in IL23R was associated with improved overall survival (hazard ratio (HR)=0.48; P=0.028) and, in donor, with decreased risk of fungal infections (P=0.05). In contrast, patient TC and CC genotypes at rs8193036 in IL17A gene were associated with increased risk of CMV infection (HR=3.68; P=0.011) and patient acute GVHD (HR=7.08; P=0.008), respectively. These results suggest that genetic variants in the IL-23/Th17 inflammatory pathway are important prognostic factors for the clinical outcome of allo-SCT. Although validation studies are ultimately required, our results would suggest the potential usefulness of IL-23/Th17 genotyping in donor selection and patient evaluation.

Variable number of tandem repeat polymorphisms of the interleukin-1 receptor antagonist gene IL-1RN: a novel association with the athlete status

BACKGROUND

The interleukin-1 (IL-1) family of cytokines is involved in the inflammatory and repair reactions of skeletal muscle during and after exercise. Specifically, plasma levels of the IL-1 receptor antagonist (IL-1ra) increase dramatically after intense exercise, and accumulating evidence points to an effect of genetic polymorphisms on athletic phenotypes. Therefore, the IL-1 family cytokine genes are plausible candidate genes for athleticism. We explored whether IL-1 polymorphisms are associated with athlete status in European subjects.

METHODS

Genomic DNA was obtained from 205 (53 professional and 152 competitive non-professional) Italian athletes and 458 non-athlete controls. Two diallelic polymorphisms in the IL-1beta gene (IL-1B) at -511 and +3954 positions, and a variable number tandem repeats (VNTR) in intron 2 of the IL-1ra gene (IL-1RN) were assessed.

RESULTS

We found a 2-fold higher frequency of the IL-1RN 1/2 genotype in athletes compared to non-athlete controls (OR = 1.93, 95% CI = 1.37-2.74, 41.0% vs. 26.4%), and a lower frequency of the 1/1 genotype (OR = 0.55, 95% CI = 0.40-0.77, 43.9% vs. 58.5%). Frequency of the IL-1RN 2/2 genotype did not differ between groups. No significant differences between athletes and controls were found for either -511 or +3954 IL-1B polymorphisms. However, the haplotype (-511)C-(+3954)T-(VNTR)2 was 3-fold more frequent in athletes than in non-athletes (OR = 3.02, 95% CI = 1.16-7.87). Interestingly, the IL-1RN 1/2 genotype was more frequent in professional than in non-professional athletes (OR = 1.92, 95% CI = 1.02-3.61, 52.8% vs. 36.8%).

CONCLUSIONS

Our study found that variants at the IL-1ra gene associate with athletic status. This confirms the crucial role that cytokine IL-1ra plays in human physical exercise. The VNTR IL-1RN polymorphism may have implications for muscle health, performance, and/or recovery capacities. Further studies are needed to assess these specific issues. As VNTR IL-1RN polymorphism is implicated in several disease conditions, athlete status may constitute a confounding variable that will need to be accounted for when examining associations of this polymorphism with disease risk.

Transcriptional control of the TNF gene

The cytokine TNF is a critical mediator of immune and inflammatory responses. The TNF gene is an immediate early gene, rapidly transcribed in a variety of cell types following exposure to a broad range of pathogens and signals of inflammation and stress. Regulation of TNF gene expression at the transcriptional level is cell type- and stimulus-specific, involving the recruitment of distinct sets of transcription factors to a compact and modular promoter region. In this review, we describe our current understanding of the mechanisms through which TNF transcription is specifically activated by a variety of extracellular stimuli in multiple cell types, including T cells, B cells, macrophages, mast cells, dendritic cells, and fibroblasts. We discuss the role of nuclear factor of activated T cells and other transcription factors and coactivators in enhanceosome formation, as well as the contradictory evidence for a role for nuclear factor kappaB as a classical activator of the TNF gene. We describe the impact of evolutionarily conserved cis-regulatory DNA motifs in the TNF locus upon TNF gene transcription, in contrast to the neutral effect of single nucleotide polymorphisms. We also assess the regulatory role of chromatin organization, epigenetic modifications, and long-range chromosomal interactions at the TNF locus.

Interleukin-7 compartmentalizes its receptor signaling complex to initiate CD4 T lymphocyte response

Interleukin (IL)-7 is a central cytokine that controls homeostasis of the CD4 T lymphocyte pool. Here we show on human primary cells that IL-7 binds to preassembled receptors made up of proprietary chain IL-7Ralpha and the common chain gammac shared with IL-2, -4, -9, -15, and -21 receptors. Upon IL-7 binding, both chains are driven in cholesterol- and sphingomyelin-rich rafts where associated signaling proteins Jak1, Jak3, STAT1, -3, and -5 are found to be phosphorylated. Meanwhile the IL-7.IL-7R complex interacts with the cytoskeleton that halts its diffusion as measured by single molecule fluorescence autocorrelated spectroscopy monitored by microimaging. Comparative immunoprecipitations of IL-7Ralpha signaling complex from non-stimulated and IL-7-stimulated cells confirmed recruitment of proteins such as STATs, but many others were also identified by mass spectrometry from two-dimensional gels. Among recruited proteins, two-thirds are involved in cytoskeleton and raft formation. Thus, early events leading to IL-7 signal transduction involve its receptor compartmentalization into membrane nanodomains and cytoskeleton recruitment.

Interleukin-23 receptor genetic polymorphisms and Crohn's disease susceptibility: a meta-analysis

OBJECTIVE

This study was designed to evaluate whether interleukin-23 receptor (IL-23R) polymorphisms were associated with Crohn's disease (CD) susceptibility.

METHODS

PubMed, MEDLINE, and Embase were searched for studies that investigated the IL-23R variants and CD risk. Meta-analysis from all eligible case-control studies was performed to assess the purported associations.

RESULTS

Our analysis found that variant minor alleles for single nucleotide polymorphisms (SNPs) rs11209026 (Arg381Gln) (P < 0.00001, OR = 0.43, 95% CI (0.37-0.50)) and rs7517847 (G/G vs. T/T, P < 0.00001, OR = 0.49, 95% CI (0.38-0.64); G/G vs. T/G + T/T, (P < 0.00001, OR = 0.56, 95% CI (0.44-0.72); T/G + G/G vs. T/T, (P < 0.00001, OR = 0.71, 95% CI (0.64-0.79) of IL-23R were inversely associated with CD risk; sensitivity analysis also indicated that Caucasian population with a variant of Arg381Gln has a decreased risk for developing CD (P < 0.00001, OR = 0.43, 95% CI (0.36-0.50)).

CONCLUSION

Our meta-analysis supports that two polymorphisms (Arg381Gln and rs7517847) within the IL-23R gene may be considered to be protective factors against developing CD. Further large case-control studies especially concerning ethnicity differences and genotype-phenotype interaction should be performed to clarify possible roles of IL-23R in CD.

CXCR7 functions as a scavenger for CXCL12 and CXCL11

BACKGROUND

CXCR7 (RDC1), the recently discovered second receptor for CXCL12, is phylogenetically closely related to chemokine receptors, but fails to couple to G-proteins and to induce typical chemokine receptor mediated cellular responses. The function of CXCR7 is controversial. Some studies suggest a signaling activity in mammalian cells and zebrafish embryos, while others indicate a decoy activity in fish. Here we investigated the two propositions in human tissues.

METHODOLOGY/PRINCIPAL FINDINGS

We provide evidence and mechanistic insight that CXCR7 acts as specific scavenger for CXCL12 and CXCL11 mediating effective ligand internalization and targeting of the chemokine cargo for degradation. Consistently, CXCR7 continuously cycles between the plasma membrane and intracellular compartments in the absence and presence of ligand, both in mammalian cells and in zebrafish. In accordance with the proposed activity as a scavenger receptor CXCR7-dependent chemokine degradation does not become saturated with increasing ligand concentrations. Active CXCL12 sequestration by CXCR7 is demonstrated in adult mouse heart valves and human umbilical vein endothelium.

CONCLUSIONS/SIGNIFICANCE

The finding that CXCR7 specifically scavenges CXCL12 suggests a critical function of the receptor in modulating the activity of the ubiquitously expressed CXCR4 in development and tumor formation. Scavenger activity of CXCR7 might also be important for the fine tuning of the mobility of hematopoietic cells in the bone marrow and lymphoid organs.

Gossypol induces apoptosis by activating p53 in prostate cancer cells and prostate tumor-initiating cells

Prostate cancer continues to represent a burgeoning medical problem in the United States. Recent studies suggest that gossypol, a bioactive phytochemical produced by cotton plants, is a promising agent against prostate cancer. The current studies were undertaken to examine the chemotherapeutic efficacy of gossypol on human prostate cancer cell lines and prostate tumor-initiating cells. Gossypol reduced the viability of three prostate cancer cell lines (LAPC4, PC3, and DU145) with an IC(50) between 3 and 5 micromol/L. Additionally, gossypol was effective at inhibiting prostate tumor-initiating cell-driven tumor growth in a nonobese diabetic/severe combined immunodeficient xenograft model. Our integrated molecular profiling approach encompassing proteomics, activated transcription factors, and genomics suggests that the decrease in viability was associated with increased DNA damage and the induction of apoptosis. Exposure of DU145 cells to gossypol (1-10 micromol/L) resulted in the activation of 13 proteins and 7 transcription factors, and the expression of 17 genes involved in the mitochondrial pathway of apoptosis. These studies show for the first time that gossypol treatment induces DNA damage and activates p53. Collectively, these data support the use of gossypol as a novel agent for prostate cancer.

The chemokine monocyte chemoattractant protein-1 contributes to renal dysfunction in swine renovascular hypertension

Renal artery stenosis (RAS) causes renovascular hypertension and renal damage, which may result from tissue inflammation. We have previously shown that the kidney in RAS exhibits increased expression of monocyte chemoattractant protein (MCP)-1, but its contribution to renal injury remained unknown. This study tested the hypothesis that MCP-1 contributes to renal injury and dysfunction in the stenotic kidney.

METHODS

Kidney hemodynamics, function, and endothelial function were quantified in pigs after 10 weeks of experimental RAS (n = 7), RAS supplemented with the MCP-1 inhibitor bindarit (RAS + bindarit, 50 mg/kg/day orally, n = 6), and normal controls (n = 8). Renal inflammation was assessed by the immunoreactivity of MCP-1, its receptor chemotactic cytokine receptor 2, and NFkappaB, and oxidative stress by nicotinamide adenine dinucleotide phosphate-oxidase expression and in-situ superoxide production. Renal microvascular density was evaluated by micro-CT and fibrosis by trichrome staining, collagen-I immunostaining, and hydroxyproline content.

RESULTS

After 10 weeks of RAS, blood pressure was similarly elevated in RAS and RAS + bindarit. Compared with normal controls, stenotic RAS kidneys had decreased renal blood flow (5.4 +/- 1.6 vs. 11.4 +/- 1.0 ml/min/kg, P < 0.05) and glomerular filtration rate and impaired endothelial function, which were significantly improved in bindarit-treated RAS pigs (to 8.4 +/- 0.8 ml/min/kg, P < 0.05 vs. RAS). Furthermore, bindarit markedly decreased tubulointerstitial (but not vascular) oxidative stress, inflammation, and fibrosis, and slightly increased renal microvascular density. The impaired renovascular endothelial function, increased oxidative-stress, and fibrosis in the contralateral kidney were also improved by bindarit.

CONCLUSION

MCP-1 contributes to functional and structural impairment in the kidney in RAS, mainly in the tubulointerstitial compartment. Its inhibition confers renoprotective effects by blunting renal inflammation and thereby preserving the kidney in chronic RAS.

Exercise training normalizes ACE and ACE2 in the brain of rabbits with pacing-induced heart failure

Exercise training (EX) normalizes sympathetic outflow and plasma ANG II in chronic heart failure (CHF). The central mechanisms by which EX reduces this sympathoexcitatory state are unclear, but EX may alter components of the brain renin-angiotensin system (RAS). Angiotensin-converting enzyme (ACE) may mediate an increase in sympathetic nerve activity (SNA). ACE2 metabolizes ANG II to ANG-(1-7), which may have antagonistic effects to ANG II. Little is known concerning the regulation of ACE and ACE2 in the brain and the effect of EX on these enzymes, especially in the CHF state. This study aimed to investigate the effects of EX on the regulation of ACE and ACE2 in the brain in an animal model of CHF. We hypothesized that the ratio of ACE to ACE2 would increase in CHF and would be reduced by EX. Experiments were performed on New Zealand White rabbits divided into the following groups: sham, sham + EX, CHF, and CHF + EX (n = 5 rabbits/group). The cortex, cerebellum, medulla, hypothalamus, paraventricular nucleus (PVN), nucleus tractus solitarii (NTS), and rostral ventrolateral medulla (RVLM) were analyzed. ACE protein and mRNA expression in the cerebellum, medulla, hypothalamus, PVN, NTS, and RVLM were significantly upregulated in CHF rabbits (ratio of ACE to GAPDH: 0.3 +/- 0.03 to 0.8 +/- 0.10 in the RVLM, P < 0.05). EX normalized this upregulation compared with CHF (0.8 +/- 0.1 to 0.4 +/- 0.1 in the RVLM). ACE2 protein and mRNA expression decreased in CHF (ratio of ACE2 to GAPDH: 0.3 +/- 0.02 to 0.1 +/- 0.01 in the RVLM). EX increased ACE2 expression compared with CHF (0.1 +/- 0.01 to 0.8 +/- 0.1 in the RVLM). ACE2 was present in the cytoplasm of neurons and ACE in endothelial cells. These data suggest that the activation of the central RAS in animals with CHF involves an imbalance of ACE and ACE2 in regions of the brain that regulate autonomic function and that EX can reverse this imbalance.

Inhibition of proliferation of prostate cancer cell line, PC-3, in vitro and in vivo using (-)-gossypol

We investigated the antiproliferative activity of (-)-gossypol on the human prostate cancer cell line PC3 in vitro and in vivo to elucidate its potential molecular mechanisms. Cell growth and viability were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell apoptosis was detected by flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) and electron microscopy. Expression of proliferating cell nuclear antigen (PCNA), Bcl-2, CD31, caspase-3 and caspase-8 in tumour tissue was determined by immunohistochemistry. The drug concentration that yielded 50% cell inhibition (IC(50) value) was 4.74 microg mL(-1). In the PC-3 tumour xenograft study, (-)-gossypol (> 5 mg kg(-1)) given once a day for 7 days significantly inhibited tumour growth in a dose-dependent manner. Immunohistochemical analysis revealed that (-)-gossypol enhanced caspase-3 and caspase-8 expression and decreased the expression of PCNA, Bcl-2 and CD31 in tumour tissues. It suggested that cell apoptosis and inhibition of angiogenesis might contribute to the anticancer action of (-)-gossypol.

Regulatory T cells modulate Th17 responses in patients with positive tuberculin skin test results

BACKGROUND

The factors governing latency in tuberculosis are not well understood but appear to involve both the pathogen and the host. We have used tuberculin skin test (TST) positivity as a tool to study cytokine responses in latent tuberculosis.

METHODS

To identify the host factors that are important in the maintenance of TST positivity, we examined mycobacteria-specific immune responses of TST-positive (latent tuberculosis) or TST-negative individuals in South India, where TST positivity can define tuberculosis latency.

RESULTS

Although purified protein derivative-specific and Mycobacterium tuberculosis culture filtrate antigen-specific Th1 and Th2 cytokines were not statistically significantly different between the 2 groups, the Th17 cytokines (interleukin 17 and interleukin 23) were statistically significantly decreased in TST-positive individuals, compared with those in TST-negative individuals. This Th17 cytokine modulation was associated with statistically significantly increased expression of cytotoxic T lymphocyte antigen 4 (CTLA-4) and Foxp3. Although CTLA-4 blockade failed to restore full production of interleukin 17 and interleukin 23 in TST-positive individuals, depletion of regulatory T cells significantly increased production of these cytokines.

CONCLUSION

TST positivity is characterized by increased activity of regulatory T cells and a coincident down-regulation of the Th17 response.

The global diabetes epidemic as a consequence of lifestyle-induced low-grade inflammation

The recent major increase in the global incidence of type 2 diabetes suggests that most cases of this disease are caused by changes in environment and lifestyle. All major risk factors for type 2 diabetes (overnutrition, low dietary fibre, sedentary lifestyle, sleep deprivation and depression) have been found to induce local or systemic low-grade inflammation that is usually transient or milder in individuals not at risk for type 2 diabetes. By contrast, inflammatory responses to lifestyle factors are more pronounced and prolonged in individuals at risk of type 2 diabetes and appear to occur also in the pancreatic islets. Chronic low-grade inflammation will eventually lead to overt diabetes if counter-regulatory circuits to inflammation and metabolic stress are compromised because of a genetic and/or epigenetic predisposition. Hence, it is not the lifestyle change per se but a deficient counter-regulatory response in predisposed individuals which is crucial to disease pathogenesis. Novel approaches of intervention may target these deficient defence mechanisms.

Modulation of fetal inflammatory response on exposure to lipopolysaccharide by chorioamnion, lung, or gut in sheep

OBJECTIVE

We hypothesized that fetal lipopolysaccharide exposures to the chorioamnion, lung, or gut would induce distinct systemic inflammatory responses.

STUDY DESIGN

Groups of 5-7 time-mated ewes were used to surgically isolate the fetal respiratory and the gastrointestinal systems from the amniotic compartment. Outcomes were assessed at 124 days gestational age, 2 days and 7 days after lipopolysaccharide (10 mg, Escherichia coli 055:B5) or saline solution infusions into the fetal airways or amniotic fluid.

RESULTS

Lipopolysaccharide induced systemic inflammatory changes in all groups in the blood, lung, liver, and thymic lymphocytes. Changes in lymphocytes in the posterior mediastinal lymph node draining lung and gut, occurred only after direct contact of lipopolysaccharide with the fetal lung or gut.

CONCLUSION

Fetal systemic inflammatory responses occurred after chorioamnion, lung, or gut exposures to lipopolysaccharide. The organ responses differed based on route of the fetal exposure.

Association of plasma leptin levels with incident Alzheimer disease and MRI measures of brain aging

CONTEXT

The adipokine leptin facilitates long-term potentiation and synaptic plasticity in the hippocampus, promotes beta-amyloid clearance, and improves memory function in animal models of aging and Alzheimer disease (AD).

OBJECTIVE

To relate baseline circulating leptin concentrations in a community-based sample of individuals without dementia to incident dementia and AD during follow-up and magnetic resonance imaging (MRI) measures of brain aging in survivors.

DESIGN, SETTING, AND PARTICIPANTS

Prospective study of plasma leptin concentrations measured in 785 persons without dementia (mean [SD] age, 79 [5] years; 62% female), who were in the Framingham original cohort at the 22nd examination cycle (1990-1994). A subsample of 198 dementia-free survivors underwent volumetric brain MRI between 1999 and 2005, approximately 7.7 years after leptin was assayed. Two measures of brain aging, total cerebral brain volume and temporal horn volume (which is inversely related to hippocampal volume) were assessed.

MAIN OUTCOME MEASURE

Incidence of dementia and AD during follow-up until December 31, 2007.

RESULTS

During a median follow-up of 8.3 years (range, 0-15.5 years), 111 participants developed incident dementia; 89 had AD. Higher leptin levels were associated with a lower risk of incident dementia and AD in multivariable models (hazard ratio per 1-SD increment in log leptin was 0.68 [95% confidence interval, 0.54-0.87] for all-cause dementia and 0.60 [95% confidence interval, 0.46-0.79] for AD). This corresponds to an absolute AD risk over a 12-year follow-up of 25% for persons in the lowest quartile (first quartile) vs 6% for persons in the fourth quartile of sex-specific leptin levels. In addition, a 1-SD elevation in plasma leptin level was associated with higher total cerebral brain volume and lower temporal horn volume, although the association of leptin level with temporal horn volume did not reach statistical significance.

CONCLUSION

Circulating leptin was associated with a reduced incidence of dementia and AD and with cerebral brain volume in asymptomatic older adults.

Massive induction of innate immune response to Candida albicans in the kidney in a murine intravenous challenge model

In the experimental Candida albicans intravenous challenge model, the kidney is one of the main organs involved in disease. In progressive infection, fungal burdens are found to increase over time, with rapid increases occurring from 24 h postinfection. Renal transcriptional responses were analyzed at this time in the kidneys of mice infected by either a virulent or an attenuated C. albicans strain, allowing comparison of host responses in progressive and nonprogressive infection. The results of this study demonstrate that both infections share a common transcriptional response, consisting of functions associated with the acute-phase reaction. In addition, challenge with the virulent strain led to a massively increased expression of cytokine genes, other innate response genes and genes suggestive of initiation of the adaptive immune response. This immune response to C. albicans infection, which occurs only in progressive infection, may contribute to development of sepsis and, ultimately, host death.

In Vitro Study of Nitric Oxide Metabolites Effects on Human Hydatid of Echinococcus granulosus

Hydatidosis is characterized by the long-term coexistence of larva Echinococcus granulosus and its host without effective rejection. Previous studies demonstrated nitric oxide (NO) production (in vivo and in vitro) during hydatidosis. In this study, we investigated the direct in vitro effects of NO species: nitrite (NO₂⁻), nitrate (NO₃⁻) and peroxynitrite (ONOO⁻) on protoscolices (PSCs) viability and hydatid cyst layers integrity for 24 hours and 48 hours. Our results showed protoscolicidal activity of NO₂⁻ and ONOO⁻ 24 hours and 3 hours after treatment with 320 μM and 80 μM respectively. Degenerative effects were observed on germinal and laminated layers. The comparison of the in vitro effects of NO species on the PSCs viability indicated that ONOO⁻ is more cytotoxic than NO₂⁻. In contrast, NO₃⁻ has no effect. These results suggest possible involvement of NO₂⁻ and ONOO⁻ in antihydatic action and point the efficacy of these metabolites as scolicidal agents.

Association of CTLA4 gene polymorphism in Iranian patients with ankylosing spondylitis

INTRODUCTION

Cytotoxic T-lymphocyte antigen 4 (CTLA-4) is a costimulatory molecule expressed by activated T cells. This study was performed to investigate the allele and genotype frequencies of CTLA4 gene polymorphisms in Iranian patients with ankylosing spondylitis (AS).

METHODS

One hundred and fifty-seven patients with AS and 103 controls were included in this study. Polymorphisms of CTLA4 gene at positions +49 (in exon 1), -318, and -1,147 (in the promoter region) were studied on the genomic DNA using PCR restriction fragment-length polymorphism method.

RESULTS

The frequencies of the T allele at position -1147 in the patients with AS was significantly increased in comparison with the control group (11% vs. 5%, P = 0.004); whereas the frequencies of C allele at the same position were significantly decreased in the patient group (89% vs. 95%, P = 0.004). Comparison of genotype frequencies at this position showed that the frequency of CT genotype in comparison with other genotypes was overrepresented in the patient group (20% vs. 8%, P = 0.012), while the CC genotype in comparison with other genotypes was decreased (79% vs. 91%, P = 0.012). There was no significant difference on frequencies of genotypes at the positions -318 and +49.

CONCLUSION

This study could suggest an association between specific allele in the promoter region of CTLA4 gene and AS disease.

IL4 gene polymorphism and previous malaria experiences manipulate anti-Plasmodium falciparum antibody isotype profiles in complicated and uncomplicated malaria

Background

The IL4-590 gene polymorphism has been shown to be associated with elevated levels of anti-Plasmodium falciparum IgG antibodies and parasite intensity in the malaria protected Fulani of West Africa. This study aimed to investigate the possible impact of IL4-590C/T polymorphism on anti-P. falciparum IgG subclasses and IgE antibodies levels and the alteration of malaria severity in complicated and uncomplicated malaria patients with or without previous malaria experiences.

Methods

Anti-P.falciparum IgG subclasses and IgE antibodies in plasma of complicated and uncomplicated malaria patients with or without previous malaria experiences were analysed using ELISA. IL4-590 polymorphisms were genotyped using RFLP-PCR. Statistical analyses of the IgG subclass levels were done by Oneway ANOVA. Genotype differences were tested by Chi-squared test.

Results

The IL4-590T allele was significantly associated with anti-P. falciparum IgG3 antibody levels in patients with complicated (P = 0.031), but not with uncomplicated malaria (P = 0.622). Complicated malaria patients with previous malaria experiences carrying IL4-590TT genotype had significantly lower levels of anti-P. falciparum IgG3 (P = 0.0156), while uncomplicated malaria patients with previous malaria experiences carrying the same genotype had significantly higher levels (P = 0.0206) compared to their IL4-590 counterparts. The different anti-P. falciparum IgG1 and IgG3 levels among IL4 genotypes were observed. Complicated malaria patients with previous malaria experiences tended to have lower IgG3 levels in individuals carrying TT when compared to CT genotypes (P = 0.075). In contrast, complicated malaria patients without previous malaria experiences carrying CC genotype had significantly higher anti-P. falciparum IgG1 than those carrying either CT or TT genotypes (P = 0.004, P = 0.002, respectively).

Conclusion

The results suggest that IL4-590C or T alleles participated differently in the regulation of anti-malarial antibody isotype profiles in primary and secondary malaria infection and, therefore, could play an important role in alteration of malaria severity.

Immune-mediated mechanisms potentially regulate the disease time-course of duchenne muscular dystrophy and provide targets for therapeutic intervention

Duchenne muscular dystrophy is a lethal muscle-wasting disease that affects boys. Mutations in the dystrophin gene result in the absence of the dystrophin glycoprotein complex (DGC) from muscle plasma membranes. In healthy muscle fibers, the DGC forms a link between the extracellular matrix and the cytoskeleton to protect against contraction-induced membrane lesions and to regulate cell signaling. The absence of the DGC results in aberrant regulation of inflammatory signaling cascades. Inflammation is a key pathological characteristic of dystrophic muscle lesion formation. However, the role and regulation of this process in the disease time-course has not been sufficiently examined. The transcription factor nuclear factor-kappaB has been shown to contribute to the disease process and is likely involved with increased inflammatory gene expression, including cytokines and chemokines, found in dystrophic muscle. These aberrant signaling processes may regulate the early time-course of inflammatory events that contribute to the onset of disease. This review critically evaluates the possibility that dystrophic muscle lesions in both patients with Duchenne muscular dystrophy and mdx mice are the result of immune-mediated mechanisms that are regulated by inflammatory signaling and also highlights new therapeutic directions.