sTREM2 Differentially Affects Cytokine Expression in Myeloid-Derived Cell Models via MAPK-JNK Signaling Pathway

TREM2 is a critical innate immune receptor primarily expressed on myeloid-derived cells, such as microglia and macrophages. Mutations in TREM2 are linked to several neurodegenerative diseases including Alzheimer's disease (AD). TREM2 can be cleaved from the cell membrane and released as soluble TREM2 (sTREM2). sTREM2 levels are shown to peak prior to AD, with its levels fluctuating throughout disease progression. However, the mechanism by which sTREM2 may affect innate immune responses is largely uncharacterized. In this study, we investigated whether sTREM2 can induce inflammatory response in myeloid-derived THP-1 monocytes and macrophages and characterized the signaling mechanisms involved. Our results show that sTREM2 was capable of stimulating the expression of several inflammatory cytokines in THP-1 cells throughout the time course of 2 h to 8 h but inducing anti-inflammatory cytokine expression at later time points. A TREM2 antibody was capable of inhibiting the expression of some cytokines induced by sTREM2 but enhancing others. The complex of sTREM2/TREM2 antibody was shown to enhance IL-1β expression, which was partially blocked by an NLRP3 specific inhibitor, indicating that the complex activated the NRLP3 inflammasome pathway. sTREM2 was also shown to have differential effects on cytokine expression in M0, M1, and M2 macrophages differentiated from THP-1 cells. sTREM2 has a more stimulating effect on cytokine expression in M0 macrophages, less of an effect on M2 macrophages, and some inhibitory effects on cytokine expression in M1 macrophages at early time points. Analyses of several signaling pathways revealed that sTREM2-induced expression of cytokines occurs mainly through MAPK-JNK signaling. Our work reveals differential effects of sTREM2 on cytokine expression profiles of THP-1 cells and macrophages and demonstrates that the MAPK-JNK signaling pathway is mainly responsible for sTREM2-induced cytokine expression.

Investigation of the physiological, behavioral, and biochemical responses of cattle to restraint stress

Stresses imposed on livestock have significant impact on their health and productivity as well as public perceptions of animal welfare. Understanding stress responses in livestock may help refine management procedures and facilitate selection of stress-tolerant animals. In this study, behavioral (chute entry order, chute behavior, and exit velocity), physiological (serum cortisol), and biochemical (kinome) responses were evaluated in cattle ( = 20) subjected to three 5-min restraint periods with weekly intervals. Correlations among stress responses were assessed across all animals as well as for subgroups ( = 4) representing animals consistently displaying a high and low extreme of serum cortisol responses. Across all animals, entry order ( = 0.006) and exit velocity ( = 0.023) were positively correlated with serum cortisol; however, these correlations were not consistently reproducible for the high and low serum cortisol responders. Kinome profiling of peripheral blood mononuclear cells revealed distinct signaling events between the high and low cortisol responders. In particular, kinome profiling revealed significant differences in carbohydrate metabolism and apoptosis that were independently validated. Furthermore, changes in serum glucose levels provided a reliable, inexpensive indicator of serum cortisol levels and often had greater predictive value than cortisol for stress-related behavioral responses. Serum cortisol levels displayed a pattern consistent with sensitization, whereas no habituation or sensitization was observed for serum glucose levels or behavioral responses. Collectively, this investigation provides insight into correlations among physiological, behavioral, and biochemical responses of cattle subjected to a brief restraint that may provide biomarkers for selection of stress-tolerant animals.

Models and Methods to Investigate Acute Stress Responses in Cattle

There is a growing appreciation within the livestock industry and throughout society that animal stress is an important issue that must be addressed. With implications for animal health, well-being, and productivity, minimizing animal stress through improved animal management procedures and/or selective breeding is becoming a priority. Effective management of stress, however, depends on the ability to identify and quantify the effects of various stressors and determine if individual or combined stressors have distinct biological effects. Furthermore, it is critical to determine the duration of stress-induced biological effects if we are to understand how stress alters animal production and disease susceptibility. Common stress models used to evaluate both psychological and physical stressors in cattle are reviewed. We identify some of the major gaps in our knowledge regarding responses to specific stressors and propose more integrated methodologies and approaches to measuring these responses. These approaches are based on an increased knowledge of both the metabolic and immune effects of stress. Finally, we speculate on how these findings may impact animal agriculture, as well as the potential application of large animal models to understanding human stress.

Peptide Arrays for Kinome Analysis of Livestock Species

Reversible protein phosphorylation is a central mechanism for both the transfer of intracellular information and the initiation of cellular responses. Within human medicine, considerable emphasis is placed on understanding and controlling the enzymes (kinases) that are responsible for catalyzing these modifications. This is evident in the prominent use of kinase inhibitors as drugs as well as the trend to understand complex biology and identify biomarkers via characterizations of global kinase (kinome) activity. Despite the demonstrated value of focusing on kinome activity, the application of this perspective to livestock has been restricted by the absence of appropriate research tools. In this review, we discuss the development of software platforms that facilitate the development and application of species-specific peptide arrays for kinome analysis of livestock. Examples of the application of kinomic approaches to a number of priority species (cattle, pigs, and chickens) in a number of biological contexts (infections, biomarker discovery, and food quality) are presented as are emerging trends for kinome analysis of livestock.

DAPPLE: a pipeline for the homology-based prediction of phosphorylation sites

SUMMARY

While many experimentally characterized phosphorylation sites exist for certain organisms, such as human, rat and mouse, few sites are known for other organisms, hampering related research efforts. We have developed a software pipeline called DAPPLE that automates the process of using known phosphorylation sites from other organisms to identify putative sites in an organism of interest.

AVAILABILITY

DAPPLE is available as a web server at http://saphire.usask.ca.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Systems kinomics demonstrates Congo Basin monkeypox virus infection selectively modulates host cell signaling responses as compared to West African monkeypox virus

Monkeypox virus (MPXV) is comprised of two clades: Congo Basin MPXV, with an associated case fatality rate of 10%, and Western African MPXV, which is associated with less severe infection and minimal lethality. We thus postulated that Congo Basin and West African MPXV would differentially modulate host cell responses and, as many host responses are regulated through phosphorylation independent of transcription or translation, we employed systems kinomics with peptide arrays to investigate these functional host responses. Using this approach we have demonstrated that Congo Basin MPXV infection selectively down-regulates host responses as compared with West African MPXV, including growth factor- and apoptosis-related responses. These results were confirmed using fluorescence-activated cell sorting analysis demonstrating that West African MPXV infection resulted in a significant increase in apoptosis in human monocytes as compared with Congo Basin MPXV. Further, differentially phosphorylated kinases were identified through comparison of our MPXV data sets and validated as potential targets for pharmacological inhibition of Congo Basin MPXV infection, including increased Akt S473 phosphorylation and decreased p53 S15 phosphorylation. Inhibition of Akt S473 phosphorylation resulted in a significant decrease in Congo Basin MPXV virus yield (261-fold) but did not affect West African MPXV. In addition, treatment with staurosporine, an apoptosis activator resulted in a 49-fold greater decrease in Congo Basin MPXV yields as compared with West African MPXV. Thus, using a systems kinomics approach, our investigation demonstrates that West African and Congo Basin MPXV differentially modulate host cell responses and has identified potential host targets of therapeutic interest.

EphB receptors trigger Akt activation and suppress Fas receptor-induced apoptosis in malignant T lymphocytes

Treatment of hematopoietic malignancies often requires allogeneic bone marrow transplantation, and the subsequent graft-versus-leukemia response is crucial for the elimination of malignant cells. Cytotoxic T lymphocytes and NK cells responsible for the immunoelimination express Fas ligand and strongly rely on the induction of Fas receptor-mediated apoptosis for their action. Although cancer cells are removed successfully by graft-versus-leukemia reactions in myeloid malignancies, their efficiency is low in T cell leukemias. This may be partially because of the ability of malignant T cells to escape apoptosis. Our work shows that Eph family receptor EphB3 is consistently expressed by malignant T lymphocytes, most frequently in combination with EphB6, and that stimulation with their common ligands, ephrin-B1 and ephrin-B2, strongly suppresses Fas-induced apoptosis in these cells. This effect is associated with Akt activation and with the inhibition of the Fas receptor-initiated caspase proteolytic cascade. Akt proved to be crucial for the prosurvival response, because inhibition of Akt, but not of other molecules central to T cell biology, including Src kinases, MEK1 and MEK2, blocked the antiapoptotic effect. Overall, this demonstrates a new role for EphB receptors in the protection of malignant T cells from Fas-induced apoptosis through Akt engagement and prevention of caspase activation. Because Fas-triggered apoptosis is actively involved in the graft-versus-leukemia response and cytotoxic T cells express ephrin-Bs, our observations suggest that EphB receptors are likely to support immunoevasivenes of T cell malignancies and may represent promising targets for therapies, aiming to enhance immunoelimination of cancerous T cells.

Inflammatory cytokines IL-32 and IL-17 have common signaling intermediates despite differential dependence on TNF-receptor 1

Cytokines IL-32 and IL-17 are emerging as critical players in the pathophysiology of immune-mediated chronic inflammatory diseases. It has been speculated that the molecular mechanisms governing IL-32- and IL-17-mediated cellular responses are differentially dependent on the TNF pathway. In this study, kinome analysis demonstrated that following stimulation with cytokine IL-32, but not IL-17, there was increased phosphorylation of a peptide target corresponding to TNF-R1. Consistent with this observation, blocking TNF-R1 resulted in a suppression of IL-32-induced downstream responses, indicating that IL-32-mediated activity may be dependent on TNF-R1. In contrast, blocking TNF-R1 did not affect IL-17-induced downstream responses. Kinome analysis also implicated p300 (transcriptional coactivator) and death-associated protein kinase-1 (DAPK-1) as signaling intermediates for both IL-32 and IL-17. Phosphorylation of p300 and DAPK-1 upon stimulation with either IL-32 or IL-17 was confirmed by immunoblots. The presence of common targets was supported by results demonstrating similar downstream responses induced in the presence of IL-32 and IL-17, such as transcriptional responses and the direct activation of NF-κB. Furthermore, knockdown of p300 and DAPK-1 altered downstream responses induced by IL-32 and IL-17, and impacted certain cellular responses induced by TNF-α and IL-1β. We hypothesize that p300 and DAPK-1 represent nodes where the inflammatory networks of IL-32 and IL-17 overlap, and that these proteins would affect both TNF-R1-dependent and -independent pathways. Therefore, p300 and DAPK-1 are viable potential therapeutic targets for chronic inflammatory diseases.

TLR9 signaling failure renders Peyer's patch regulatory B cells unresponsive to stimulation with CpG oligodeoxynucleotides

Intestinal Peyer's patch (PP) regulatory CD21+ B cells (B(regs)) suppress TLR9-induced innate immune responses. However, it is not known whether TLR9 activation is regulated in PP B(regs). Here, we investigated the responses of PP B(regs) to stimulation with the TLR9 agonist CpG oligodeoxynucleotides (ODN). We observed that PP CD21+ B(regs) express high levels of TLR9 mRNA, but fail to proliferate when stimulated with CpG ODN. Furthermore, unlike CD21+ B cells from blood, PP CD21+ B(regs) do not secrete IgM or IL-12 following CpG ODN stimulation. We hypothesized that the unresponsiveness of PP B(regs) to CpG stimulation was due to an inability of the TLR9 agonist to activate the TLR9 signaling pathway in these cells. This was confirmed by kinome analysis which demonstrated dynamic patterns of phosphorylation of key TLR adaptor proteins such as IRAK1, TAK1, IKK and NF-kappaB-p65 in CpG-stimulated blood CD21+ B cells, consistent with activation of the TLR9 pathway. In contrast, stimulation of PP CD21+ B(regs) with CpG ODN resulted in phosphorylation patterns of these adaptor proteins suggestive of inactivation of the TLR9 pathway. The absence of apparent TLR9 signaling events immediately following stimulation indicated that signaling is blocked close to the receptor. Our observations suggest a novel mechanism by which the host regulates TLR responses in TLR-expressing cells with regulatory functions.

Genome to kinome: species-specific peptide arrays for kinome analysis

Tools for conducting high-throughput kinome analysis do not exist for many species. For example, two commonly used techniques for monitoring phosphorylation events are phosphorylation-specific antibodies and peptide arrays. The majority of phosphorylation-specific antibodies are for human or mouse targets, and the construction of peptide arrays relies on information from phosphorylation databases, which are similarly biased toward human and mouse data. This is a substantial obstacle because many species other than mouse represent important biological models. On the basis of the observation that phosphorylation events are often conserved across species with respect to their relative positioning within proteins and their biological function, we demonstrate that it is possible to predict the sequence contexts of phosphorylation events in other species for the production of peptide arrays for kinome analysis. Through this approach, genomic information can be rapidly used to create inexpensive, customizable, species-specific peptide arrays for high-throughput kinome analysis. We anticipate that these arrays will be valuable for investigating the conservation of biological responses across species, validating animal models of disease, and translating research to clinical applications.

[Characteristics of the populations at the Robert Giffard Psychiatric Hospital Center: people with intellectual deficiencies and people with mental disorders]

Within the context of the general reorganization of health care and social services in Québec, the present study aims at describing physical and mental characteristics of persons with mental health problems and who are mentally retarded still hospitalized in a psychiatric hospital. In the first study, 146 mentally retarded persons of which 74 formed the community group and 72 the institutionalized group. The results indicate that 84% of the mentally retarded persons still hospitalized manifested sufficiently important needs on the three measured variables (health, deficits and behaviors) to justify intensive care in a structured environment. The Behavior variable is more important in deciding the integration of these people in the community. As most of these persons have a higher level of disabilities and more behavior manifestations, the support required for these people in the community and persons delivering services will have to be more structured and intensive in nature. In the second study, 928 psychiatric patients still hospitalized were studied on the variables, age, sex, diagnostics and the global scores (physical and mental) of the level of care survey and functional autonomy. The results show that the proportion of women in the age group 35 and older were progressively increasing in relation to the men. The primary diagnostic reported more frequently was schizophrenia in 70% of cases. In the evaluation of physical care of the people still hospitalized, age becomes an important factor. Generally speaking, the population within the institution is aging and women are progressively growing in number. As these people expressed more physical ailments and a decline in basic autonomy, more structured and specialized care and support will be required to respond to their needs.

Waveguide propagation-loss measurement technique

A novel nondestructive propagation-loss measurement technique for single-mode waveguides is demonstrated. The method calculates the total propagation-loss coefficient from the measured ratio of the retroreflected and transmitted light from the waveguide and is independent of the coupling efficiency of the input light. A surface-wave transducer is utilized as an acousto-optic modulator in a lock-in scheme to enhance the measurement ease and precision.

Metal-dielectric photosystems

Thin film photosystems based on copper doped lead iodide are presented. A photodecomposable Fabry-Perot type interference filter is described and also a cerment system in which copper and lead iodide are evaporated simultaneously. These systems do not require any development, and additional information can be added subsequent to the first exposure. The proposed systems are generalizable to several metals and dielectrics.

Fabrication of metal-dielectric interference filters: a simple method

A simple and direct method for the fabrication of metal-dielectric Fabry-Perot interference filters is proposed. This phase-correction method does not require any complex calculations, and the monitoring is done directly on the system in formation. Experimental filters have been realized and are compared with the theory.