Exploiting the pro-resolving actions of glucocorticoid-induced proteins Annexin A1 and GILZ in infectious diseases.

For decades, glucocorticoids (GC) have been used to treat several inflammatory conditions, including chronic and autoimmune diseases, due to their potent anti-inflammatory properties. In the context of infectious diseases, the use of GCs may be effective as adjuvant to antibiotic therapy by controlling excessive inflammatory responses resulting in better outcome in some cases. However, the use of GCs has been associated with a vast number of side effects, including increased probability of immunosuppression and consequent risk of opportunistic infection. Glucocorticoid-induced leucine zipper (GILZ) and Annexin A1 (AnxA1) are GC-induced proteins intrinsically involved with the anti-inflammatory functions of GCs without the associated adverse metabolic effects. Recent studies have shown that these GC-proteins exhibit pro-resolving effects. An essential characteristic of pro-resolving molecules is their ability to coordinate the resolution of inflammation and promote host defense in most experimental models of infection. Although the role of GILZ and AnxA1 in the context of infectious diseases remain to be better explored, herein we provide an overview of the emerging functions of these GC-proteins obtained from pre-clinical models of infectious diseases

Resolution of inflammation: Mechanisms and opportunity for drug development

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Glucocorticoid-induced leucine zipper modulates macrophage polarization and apoptotic cell clearance.

Macrophages are professional phagocytes that display remarkable plasticity, with a range of phenotypes that can be broadly characterized by the M1/M2 dichotomy. Glucocorticoid (GC)-induced leucine zipper (GILZ) is a protein known to mediate anti-inflammatory and some pro-resolving actions, including as neutrophil apoptosis. However, the role of GILZ in key macrophage function is not well understood. Here, we investigated the role of GILZ on macrophage reprogramming and efferocytosis. Using murine bone-marrow-derived macrophages (BMDMs), we found that GILZ was expressed in naive BMDMs and exhibited increased expression in M2-like macrophages (IL4-differentiated). M1-like macrophages (IFN/LPS-differentiated) from GILZ-/- mice showed higher expression of the M1 markers CD86, MHC class II, iNOS, IL-6 and TNF-α, associated with increased levels of phosphorylated STAT1 and lower IL-10 levels, compared to M1-differentiated cells from WT mice. There were no changes in the M2 markers CD206 and arginase-1 in macrophages from GILZ-/- mice differentiated with IL-4, compared to cells from WT animals. Treatment of M1-like macrophages with TAT-GILZ, a cell-permeable GILZ fusion protein, decreased the levels of CD86 and MHC class II in M1-like macrophages without modifying CD206 levels in M2-like macrophages. In line with the in vitro data, increased numbers of M1-like macrophages were found into the pleural cavity of GILZ-/- mice after LPS-injection, compared to WT mice. Moreover, efferocytosis was defective in the context of GILZ deficiency, both in vitro and in vivo. Conversely, treatment of LPS-injected mice with TAT-GILZ promoted inflammation resolution, associated with lower numbers of M1-like macrophages and increased efferocytosis. Collectively, these data indicate that GILZ is a regulator of important macrophage functions, contributing to macrophage reprogramming and efferocytosis, both key steps for the resolution of inflammation

IFN-γ Production Depends on IL-12 and IL-18 Combined Action and Mediates Host Resistance to Dengue Virus Infection in a Nitric Oxide-Dependent Manner

Dengue is a mosquito-borne disease caused by one of four serotypes of Dengue virus (DENV-1–4). Severe dengue infection in humans is characterized by thrombocytopenia, increased vascular permeability, hemorrhage and shock. However, there is little information about host response to DENV infection. Here, mechanisms accounting for IFN-γ production and effector function during dengue disease were investigated in a murine model of DENV-2 infection. IFN-γ expression was greatly increased after infection of mice and its production was preceded by increase in IL-12 and IL-18 levels. In IFN-γ−/− mice, DENV-2-associated lethality, viral loads, thrombocytopenia, hemoconcentration, and liver injury were enhanced, when compared with wild type-infected mice. IL-12p40−/− and IL-18−/− infected-mice showed decreased IFN-γ production, which was accompanied by increased disease severity, higher viral loads and enhanced lethality. Blockade of IL-18 in infected IL-12p40−/− mice resulted in complete inhibition of IFN-γ production, greater DENV-2 replication, and enhanced disease manifestation, resembling the response seen in DENV-2-infected IFN-γ−/− mice. Reduced IFN-γ production was associated with diminished Nitric Oxide-synthase 2 (NOS2) expression and NOS2−/− mice had elevated lethality, more severe disease evolution and increased viral load after DENV-2 infection. Therefore, IL-12/IL-18-induced IFN-γ production and consequent NOS2 induction are of major importance to host resistance against DENV infection

Oral treatment with Saccharomyces cerevisiae strain UFMG 905 modulates immune responses and interferes with signal pathways involved in the activation of inflammation in a murine model of typhoid fever

AbstractSalmonella spp. are Gram-negative, facultative, intracellular pathogens that cause several diarrheal diseases ranging from self-limiting gastroenteritis to typhoid fever. Previous results from our laboratory showed that Saccharomyces cerevisiae strain UFMG 905 isolated from ‘cachaça’ production presented probiotic properties due to its ability to protect against experimental infection with Salmonella enterica serovar Typhimurium. In this study, the effects of oral treatment with S. cerevisiae 905 were evaluated at the immunological level in a murine model of typhoid fever. Treatment with S. cerevisiae 905 inhibited weight loss and increased survival rate after Salmonella challenge. Immunological data demonstrated that S. cerevisiae 905 decreased levels of proinflammatory cytokines and modulated the activation of mitogen-activated protein kinases (p38 and JNK, but not ERK1/2), NF-κB and AP-1, signaling pathways which are involved in the transcriptional activation of proinflammatory mediators. Experiments in germ-free mice revealed that probiotic effects were due, at least in part, to the binding of Salmonella to the yeast. In conclusion, S. cerevisiae 905 acts as a potential new biotherapy against S. Typhimurium infection due to its ability to bind bacteria and modulate signaling pathways involved in the activation of inflammation in a murine model of typhoid fever

In the matter of the request of Liberty Mutual Fire Insurance Company, a Massachusetts domestic stock insurance company, to redomesticate to the state of Wisconsin

Submitted by Nuzia Santos ([email protected]) on 2018-08-24T16:36:28Z No. of bitstreams: 1 Phosphatidyl Inositol 3 Kinase-Gamma Balances.pdf: 10035595 bytes, checksum: 5a61fb2c618990d4314d36db3868ee2e (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2018-08-24T16:44:27Z (GMT) No. of bitstreams: 1 Phosphatidyl Inositol 3 Kinase-Gamma Balances.pdf: 10035595 bytes, checksum: 5a61fb2c618990d4314d36db3868ee2e (MD5)Made available in DSpace on 2018-08-24T16:44:27Z (GMT). No. of bitstreams: 1 Phosphatidyl Inositol 3 Kinase-Gamma Balances.pdf: 10035595 bytes, checksum: 5a61fb2c618990d4314d36db3868ee2e (MD5) Previous issue date: 2018Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Vírus Respiratórios e do Sarampo. Rio de Janeiro, RJ, Brazil / Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Fisiologia e Biofísica. Laboratório de Imunologia e Mecânica Pulmonar. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hanseníase. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hanseníase. Rio de Janeiro, RJ, Brazil / UNIFRANZ. Coordinación Nacional de Investigación. La Paz, Bolivia.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Morfologia. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade de São Paulo. Departamento de Farmacologia. Laboratório de Inflamação e Dor. Universidade de São Paulo. Ribeirão Preto, SP, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Vírus Respiratórios e do Sarampo. Rio de Janeiro, RJ, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Imunologia de Doenças Virais. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Biologia Geral. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hanseníase. Rio de Janeiro, RJ, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de RNA de Interferência Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Vírus Respiratórios e do Sarampo. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Imunologia de Doenças Virais. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade Federal de Minas Gerais. Faculdade de Farmácia. Departamento de Análises Clínicas e Toxicológicas. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Fisiologia e Biofísica. Laboratório de Imunologia e Mecânica Pulmonar. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil.Influenza A virus (IAV) infection causes severe pulmonary disease characterized by intense leukocyte infiltration. Phosphoinositide-3 kinases (PI3Ks) are central signaling enzymes, involved in cell growth, survival, and migration. Class IB PI3K or phosphatidyl inositol 3 kinase-gamma (PI3Kγ), mainly expressed by leukocytes, is involved in cell migration during inflammation. Here, we investigated the contribution of PI3Kγ for the inflammatory and antiviral responses to IAV. PI3Kγ knockout (KO) mice were highly susceptible to lethality following infection with influenza A/WSN/33 H1N1. In the early time points of infection, infiltration of neutrophils was higher than WT mice whereas type-I and type-III IFN expression and p38 activation were reduced in PI3Kγ KO mice resulting in higher viral loads when compared with WT mice. Blockade of p38 in WT macrophages infected with IAV reduced levels of interferon-stimulated gene 15 protein to those induced in PI3Kγ KO macrophages, suggesting that p38 is downstream of antiviral responses mediated by PI3Kγ. PI3Kγ KO-derived fibroblasts or macrophages showed reduced type-I IFN transcription and altered pro-inflammatory cytokines suggesting a cell autonomous imbalance between inflammatory and antiviral responses. Seven days after IAV infection, there were reduced infiltration of natural killer cells and CD8+ T lymphocytes, increased concentration of inflammatory cytokines in bronchoalveolar fluid, reduced numbers of resolving macrophages, and IL-10 levels in PI3Kγ KO. This imbalanced environment in PI3Kγ KO-infected mice culminated in enhanced lung neutrophil infiltration, reactive oxygen species release, and lung damage that together with the increased viral loads, contributed to higher mortality in PI3Kγ KO mice compared with WT mice. In humans, we tested the genetic association of disease severity in influenza A/H1N1pdm09-infected patients with three potentially functional PIK3CG single-nucleotide polymorphisms (SNPs), rs1129293, rs17847825, and rs2230460. We observed that SNPs rs17847825 and rs2230460 (A and T alleles, respectively) were significantly associated with protection from severe disease using the recessive model in patients infected with influenza A(H1N1)pdm09. Altogether, our results suggest that PI3Kγ is crucial in balancing antiviral and inflammatory responses to IAV infection

A Model of DENV-3 Infection That Recapitulates Severe Disease and Highlights the Importance of IFN-γ in Host Resistance to Infection

There are few animal models of dengue infection, especially in immunocompetent mice. Here, we describe alterations found in adult immunocompetent mice inoculated with an adapted Dengue virus (DENV-3) strain. Infection of mice with the adapted DENV-3 caused inoculum-dependent lethality that was preceded by several hematological and biochemical changes and increased virus dissemination, features consistent with severe disease manifestation in humans. IFN-γ expression increased after DENV-3 infection of WT mice and this was preceded by increase in expression of IL-12 and IL-18. In DENV-3-inoculated IFN-γ−/− mice, there was enhanced lethality, which was preceded by severe disease manifestation and virus replication. Lack of IFN-γ production was associated with diminished NO-synthase 2 (NOS2) expression and higher susceptibility of NOS2−/− mice to DENV-3 infection. Therefore, mechanisms of protection to DENV-3 infection rely on IFN-γ-NOS2-NO-dependent control of viral replication and of disease severity, a pathway showed to be relevant for resistance to DENV infection in other experimental and clinical settings. Thus, the model of DENV-3 infection in immunocompetent mice described here represents a significant advance in animal models of severe dengue disease and may provide an important tool to the elucidation of immunopathogenesis of disease and of protective mechanisms associated with infection

Induction of Eosinophil Apoptosis by the Cyclin-Dependent Kinase Inhibitor AT7519 Promotes the Resolution of Eosinophil-Dominant Allergic Inflammation

Eosinophils not only defend the body against parasitic infection but are also involved in pathological inflammatory allergic diseases such as asthma, allergic rhinitis and contact dermatitis. Clearance of apoptotic eosinophils by macrophages is a key process responsible for driving the resolution of eosinophilic inflammation and can be defective in allergic diseases. However, enhanced resolution of eosinophilic inflammation by deliberate induction of eosinophil apoptosis using pharmacological agents has not been previously demonstrated. Here we investigated the effect of a novel cyclin-dependent kinase inhibitor drug, AT7519, on human and mouse eosinophil apoptosis and examined whether it could enhance the resolution of a murine model of eosinophil-dominant inflammation in vivo.Eosinophils from blood of healthy donors were treated with AT7519 and apoptosis assessed morphologically and by flow-cytometric detection of annexin-V/propidium iodide staining. AT7519 induced eosinophil apoptosis in a concentration dependent manner. Therapeutic administration of AT7519 in eosinophil-dominant allergic inflammation was investigated using an established ovalbumin-sensitised mouse model of allergic pleurisy. Following ovalbumin challenge AT7519 was administered systemically at the peak of pleural inflammation and inflammatory cell infiltrate, apoptosis and evidence of macrophage phagocytosis of apoptotic eosinophils assessed at appropriate time points. Administration of AT7519 dramatically enhanced the resolution of allergic pleurisy via direct induction of eosinophil apoptosis without detriment to macrophage clearance of these cells. This enhanced resolution of inflammation was shown to be caspase-dependent as the effects of AT7519 were reduced by treatment with a broad spectrum caspase inhibitor (z-vad-fmk).Our data show that AT7519 induces human eosinophil apoptosis and enhances the resolution of a murine model of allergic pleurisy by inducing caspase-dependent eosinophil apoptosis and enhancing macrophage ingestion of apoptotic eosinophils. These findings demonstrate the utility of cyclin-dependent kinase inhibitors such as AT7519 as potential therapeutic agents for the treatment of eosinophil dominant allergic disorders

Platelet-Activating Factor Receptor Plays a Role in Lung Injury and Death Caused by Influenza A in Mice

Influenza A virus causes annual epidemics which affect millions of people worldwide. A recent Influenza pandemic brought new awareness over the health impact of the disease. It is thought that a severe inflammatory response against the virus contributes to disease severity and death. Therefore, modulating the effects of inflammatory mediators may represent a new therapy against Influenza infection. Platelet activating factor (PAF) receptor (PAFR) deficient mice were used to evaluate the role of the gene in a model of experimental infection with Influenza A/WSN/33 H1N1 or a reassortant Influenza A H3N1 subtype. The following parameters were evaluated: lethality, cell recruitment to the airways, lung pathology, viral titers and cytokine levels in lungs. The PAFR antagonist PCA4248 was also used after the onset of flu symptoms. Absence or antagonism of PAFR caused significant protection against flu-associated lethality and lung injury. Protection was correlated with decreased neutrophil recruitment, lung edema, vascular permeability and injury. There was no increase of viral load and greater recruitment of NK1.1+ cells. Antibody responses were similar in WT and PAFR-deficient mice and animals were protected from re-infection. Influenza infection induces the enzyme that synthesizes PAF, lyso-PAF acetyltransferase, an effect linked to activation of TLR7/8. Therefore, it is suggested that PAFR is a disease-associated gene and plays an important role in driving neutrophil influx and lung damage after infection of mice with two subtypes of Influenza A. Further studies should investigate whether targeting PAFR may be useful to reduce lung pathology associated with Influenza A virus infection in humans

FVIIa-antithrombin levels in early and late preeclampsia

Background Preeclampsia (PE) is associated with a hypercoagulability state. According to the gestational age (GA) at the onset of the disease, PE has been classified as early (GA < 34 weeks) and late (GA ≥ 34 weeks). It has been admitted that early PE is associated with ischemic placental lesions, while in late PE an adequate or slightly impaired placentation occurs, which suggests that the two clinical forms have distinct etiology. Tissue factor (TF) binds and activates plasma factor VII triggering the coagulation. The inhibitor antithrombin (AT), along with tissue factor pathway inhibitor, acts as an inhibitor of the FVIIa-TF pathway. Once the TF-FVIIa complex is formed, the binding and transfer of FVIIa to AT is facilitated and FVIIa activity is inhibited. Objective: We evaluated the FVIIa-AT complex levels in pregnant women with early and late severe PE (sPE), in order to verify if this biomarker can be useful for discriminating the two forms of the disease. Methods We evaluated 26 pregnant with severe early PE and 19 pregnant with severe late PE. FVIIa-AT levels were measured by STACLOT® (Diagnostica Stago). Statistical analysis was done by Mann-Whitney test. Results: Increased FVIIa-AT levels were found in early sPE [148.4 pM (137.1)] compared to late sPE [95.9 pM (66.5)] (P = 0.046), which suggests a higher pro-coagulant state when PE onset occurs before 34 weeks of gestation. Conclusion: These pioneer data allow inferring the relevance of FVIIa-AT as a device for early sPE diagnosis. However, the clinical relevance of FVIIa-AT complex surely needs to be fully clarified