Antimicrobial peptides (AMPs) are essential components of innate immunity in a range of species fromDrosophila to humans and are generally thought to act by disrupting the membrane integrity of microbes. In order to discover novel AMPs in the chicken, we have implemented a bioinformatic approach that involves the clustering of more than 420,000 chicken expressed sequence tags (ESTs). Similarity searching of proteinspredicted to be encoded by these EST clusters-for homology to known AMPs has resulted in the in silico identification of full-length sequences for seven novel gallinacins (Gal-4 to Gal-10), a novel cathelicidin and a novel liver-expressed antimicrobial peptide 2 (LEAP-2) in the chicken. Differential gene expression of these novel genes has been demonstrated across a panel of chicken tissues. An evolutionary analysis of the gallinacin family has detected sites-primarily in the mature AMP-that are under positive selection in these molecules. The functional implications of these results are discussed.

Treatment with immune complexes, which ligate Fcc receptors (FccRs), suppresses the development of experimental autoimmune encephalomyelitis (EAE). To determine the mechanism of action, we investigated how these immune complexes affected type II activation of macrophages (that is, exposure to immune complexes in a proinflammatory environment). Our results show that lower doses of interferon-c (IFN-c) were more effective at priming bone marrow-derived macrophages (BMM/) to produce more interleukin 10 (IL-10) and less IL-12p40 in response to lipopolysaccharide (LPS) and immune complexes compared with LPS alone. Moreover, at the lowest level of IFN-c (20 U ml À1 ), a significant downregulation in the surface expression of CD40, CD80 and PD-L1 was observed in LPS and immune complex-stimulated macrophages (that is, type II activated) than macrophages stimulated with LPS alone (that is, classically activated). Finally, treatment of mice with type II-activated macrophages protected them from developing EAE, suggesting that administration of immune complexes is protective against EAE by inducing type II-activated macrophages.

Antimicrobial peptides are essential components of innate immunity and are generally thought to act by disrupting the membrane integrity of microbes. Here we report the discovery of two novel chicken beta-defensins, gallinacin (Gal)-11 and Gal-12, found by hidden Markov model profile searching of the chicken genome. We have sequenced the genes and elucidated the 3'UTR of Gal-11. Differential mRNA expression of these novel genes has been shown across a panel of chicken tissues. Gal-11 mRNA was highly expressed in the small intestine, the liver, the gall bladder and the spleen and also showed moderate expression in several other areas of the chicken anatomy, whilst Gal-12 mRNA was found only in the liver and the gall bladder. Antimicrobial activity of synthetic Gal-11 has been demonstrated against a range of bacteria and is predominantly active against the intestinal pathogens Salmonella typhimurium and Listeria monocytogenes.

Summary IL-12p40 and macrophages are essential for the induction of disease in the mouse model of multiple sclerosis, experimental autoimmune encephalomyelitis. In this paper, we show that treatment of mice with opsonized erythrocytes, which have been shown to ligate Fcg receptors on macrophages and alter their cytokine profile, significantly delayed the onset of experimental autoimmune encephalomyelitis. This protection correlated to the induction of Th2 responses by autoreactive T cells, enhanced basal systemic responses and a significant downregulation of IL12p40 and nitric oxide synthase-2, but not IFN-g expression. IL-4 was essential for the protection by opsonized erythrocytes as the effects of treatment were eliminated in IL-4-deficient mice. Together these studies suggest that the ligation of Fcg receptors can modify the development of autoimmune disease by altering macrophage activation and enhancing Th2 responses.

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Type II diabetes is considered the most common metabolic disorder in the developed world and currently affects about one in ten globally. A therapeutic target for the management of type II diabetes is the inhibition of α- glucosidase, an essential enzyme located at the brush border of the small intestinal epithelium. The inhibition of α-glucosidase results in reduced digestion of carbohydrates and a decrease in postprandial blood glucose. Although pharmaceutical synthetic inhibitors are available, these are usually associated with significant gastrointestinal side effects. In the present study, the impact of inhibitors derived from edible brown algae is being investigated and compared for their effect on glycaemic control. Carbohydrate- and polyphenolic-enriched extracts derived from Ascophyllum nodosum, Fucus vesiculosus and Undaria pinnatifida were characterised and screened for their inhibitory effects on maltase and sucrase enzymes. Furthermore, enzyme kinetics and the mechanism of inhibition of maltase and sucrase were determined using linear and nonlinear regression methods. All tested extracts showed a dose-dependent inhibitory effect of α-glucosidase with IC50 values ranging from 0⋅26 to 0⋅47 mg/ml for maltase; however, the only extract that was able to inhibit sucrase activity was A. nodosum, with an IC50 value of 0⋅83 mg/ml. The present study demonstrates the mechanisms in which different brown seaweed extracts with varying composition and molecular weight distribution differentially inhibit α-glucosidase activities. The data highlight that all brown seaweed extracts are not equal in the inhibition of carbohydrate digestive enzymes involved in postprandial glycaemia.

Attempts to propagate Eimeria tenella in cell culture over the years have met with limited success. The host cell type is an important parameter in such cultures. This study assessed the ability of different host cell lines to support E. tenella infection in vitro. The initial development in cell lines and the effects of incubation at 37 degrees C and 41 degrees C on the host-parasite relationship was investigated. Eleven cell lines were seeded into 96 well plates and incubated at 37 degrees C in 5% CO(2) to reach confluency. Sporozoites of E. tenella were inoculated into wells and allowed to invade at 37 degrees C and 41 degrees C. Intracellular parasite development was quantified using (3)H-uracil incorporation. All cell lines facilitated parasite invasion and development. The MDBK cell line supported the highest degree of E. tenella development. A time-course study was undertaken to look at this host cell-parasite relationship during infection.

IntroductionThe use of anti-retroviral therapy (ART) has dramatically reduced HIV-1 associated morbidity and mortality. However, HIV-1 infected individuals have increased rates of morbidity and mortality compared to the non-HIV-1 infected population and this appears to be related to end-organ diseases collectively referred to as Serious Non-AIDS Events (SNAEs). Circulating miRNAs are reported as promising biomarkers for a number of human disease conditions including those that constitute SNAEs. Our study sought to investigate the potential of selected miRNAs in predicting mortality in HIV-1 infected ART treated individuals.Materials and MethodsA set of miRNAs was chosen based on published associations with human disease conditions that constitute SNAEs. This case: control study compared 126 cases (individuals who died whilst on therapy), and 247 matched controls (individuals who remained alive). Cases and controls were ART treated participants of two pivotal HIV-1 trials. The relative abundance of each miRNA in serum was measured, by RTqPCR. Associations with mortality (all-cause, cardiovascular and malignancy) were assessed by logistic regression analysis. Correlations between miRNAs and CD4+ T cell count, hs-CRP, IL-6 and D-dimer were also assessed.ResultsNone of the selected miRNAs was associated with all-cause, cardiovascular or malignancy mortality. The levels of three miRNAs (miRs -21, -122 and -200a) correlated with IL-6 while miR-21 also correlated with D-dimer. Additionally, the abundance of miRs -31, -150 and -223, correlated with baseline CD4+ T cell count while the same three miRNAs plus miR-145 correlated with nadir CD4+ T cell count.DiscussionNo associations with mortality were found with any circulating miRNA studied. These results cast doubt onto the effectiveness of circulating miRNA as early predictors of mortality or the major underlying diseases that contribute to mortality in participants treated for HIV-1 infection.