Integrative DNA, RNA, and protein evidence connects TREML4 to coronary artery calcification.

Coronary artery calcification (CAC) is a heritable and definitive morphologic marker of atherosclerosis that strongly predicts risk for future cardiovascular events. To search for genes involved in CAC, we used an integrative transcriptomic, genomic, and protein expression strategy by using next-generation DNA sequencing in the discovery phase with follow-up studies using traditional molecular biology and histopathology techniques. RNA sequencing of peripheral blood from a discovery set of CAC cases and controls was used to identify dysregulated genes, which were validated by ClinSeq and Framingham Heart Study data. Only a single gene, TREML4, was upregulated in CAC cases in both studies. Further examination showed that rs2803496 was a TREML4 cis-eQTL and that the minor allele at this locus conferred up to a 6.5-fold increased relative risk of CAC. We characterized human TREML4 and demonstrated by immunohistochemical techniques that it is localized in macrophages surrounding the necrotic core of coronary plaques complicated by calcification (but not in arteries with less advanced disease). Finally, we determined by von Kossa staining that TREML4 colocalizes with areas of microcalcification within coronary plaques. Overall, we present integrative RNA, DNA, and protein evidence implicating TREML4 in coronary artery calcification. Our findings connect multimodal genomics data with a commonly used clinical marker of cardiovascular disease.

LAB/NTAL facilitates fungal/PAMP-induced IL-12 and IFN-γ production by repressing ß-catenin activation in dendritic cells.

Fungal pathogens elicit cytokine responses downstream of immunoreceptor tyrosine-based activation motif (ITAM)-coupled or hemiITAM-containing receptors and TLRs. The Linker for Activation of B cells/Non-T cell Activating Linker (LAB/NTAL) encoded by Lat2, is a known regulator of ITAM-coupled receptors and TLR-associated cytokine responses. Here we demonstrate that LAB is involved in anti-fungal immunity. We show that Lat2-/- mice are more susceptible to C. albicans infection than wild type (WT) mice. Dendritic cells (DCs) express LAB and we show that it is basally phosphorylated by the growth factor M-CSF or following engagement of Dectin-2, but not Dectin-1. Our data revealed a unique mechanism whereby LAB controls basal and fungal/pathogen-associated molecular patterns (PAMP)-induced nuclear ß-catenin levels. This in turn is important for controlling fungal/PAMP-induced cytokine production in DCs. C. albicans- and LPS-induced IL-12 and IL-23 production was blunted in Lat2-/- DCs. Accordingly, Lat2-/- DCs directed reduced Th1 polarization in vitro and Lat2-/- mice displayed reduced Natural Killer (NK) and T cell-mediated IFN-γ production in vivo/ex vivo. Thus our data define a novel link between LAB and ß-catenin nuclear accumulation in DCs that facilitates IFN-γ responses during anti-fungal immunity. In addition, these findings are likely to be relevant to other infectious diseases that require IL-12 family cytokines and an IFN-γ response for pathogen clearance.

Soluble TREM-like transcript-1 regulates leukocyte activation and controls microbial sepsis.

The triggering receptor expressed on myeloid cells (TREM)-1 plays a crucial role during the onset of sepsis by amplifying the host immune response. The TREM-like transcript-1 (TLT-1) belongs to the TREM family, is selectively expressed on activated platelets, and is known to facilitate platelet aggregation through binding to fibrinogen. In this study, we show that a soluble form of TLT-1 is implicated in the regulation of inflammation during sepsis by dampening leukocyte activation and modulating platelet-neutrophil crosstalk. A 17-aa sequence of the TLT-1 extracellular domain (LR17) is responsible for this activity through competition with the TREM-1 ligand. Whereas early or late LR17 treatment of septic mice improves survival, treml-1(-/-) animals are highly susceptible to polymicrobial infection. The present findings identify platelet-derived soluble TLT-1 as a potent endogenous regulator of sepsis-associated inflammation and open new therapeutic perspectives. We anticipate soluble TLT-1 to be important in regulating leukocyte activation during other noninfectious inflammatory disorders.

A qualitative analysis of information sharing for children with medical complexity within and across health care organizations.

BACKGROUND: Children with medical complexity (CMC) are characterized by substantial family-identified service needs, chronic and severe conditions, functional limitations, and high health care use. Information exchange is critically important in high quality care of complex patients at high risk for poor care coordination. Written care plans for CMC are an excellent test case for how well information sharing is currently occurring. The purpose of this study was to identify the barriers to and facilitators of information sharing for CMC across providers, care settings, and families. METHODS: A qualitative study design with data analysis informed by a grounded theory approach was utilized. Two independent coders conducted secondary analysis of interviews with parents of CMC and health care professionals involved in the care of CMC, collected from two studies of healthcare service delivery for this population. Additional interviews were conducted with privacy officers of associated organizations to supplement these data. Emerging themes related to barriers and facilitators to information sharing were identified by the two coders and the research team, and a theory of facilitators and barriers to information exchange evolved. RESULTS: Barriers to information sharing were related to one of three major themes; 1) the lack of an integrated, accessible, secure platform on which summative health care information is stored, 2) fragmentation of the current health system, and 3) the lack of consistent policies, standards, and organizational priorities across organizations for information sharing. Facilitators of information sharing were related to improving accessibility to a common document, expanding the use of technology, and improving upon a structured communication plan. CONCLUSIONS: Findings informed a model of how various barriers to information sharing interact to prevent optimal information sharing both within and across organizations and how the use of technology to improve communication and access to information can act as a solution.

Environmental factors determine DAP12 deficiency to either enhance or suppress immunopathogenic processes.

DNAX-activation protein 12 (DAP12), a transmembrane adapter, plays a major role in transducing activation signals in natural killer cells and various myeloid cells. Quantitative RT-PCR detected in normal mouse eyes considerable levels of DAP12 and multiple DAP12-coupled receptors, in particular TREM-1, Clec5a and SIRPb1. The role of DAP12 and its receptors in experimental autoimmune diseases has been controversial. Here, we analysed the effect of DAP12 deficiency on the capacity of mice to mount immunopathogenic cellular responses to the uveitogenic ocular antigen and interphotoreceptor retinoid-binding protein (IRBP), and to develop experimental autoimmune uveitis (EAU). Surprisingly, sequential analysis of EAU in mice deficient in DAP12 in two different animal facilities at first revealed enhanced disease as compared with wild-type mice, but when these mice were re-derived into a second, cleaner, animal facility, the response of control mice was essentially unchanged, whereas the DAP12 null mice were markedly hyporesponsive relative to controls in the new facility. Accordingly, when stimulated in vitro with IRBP, lymphocytes from the DAP12-deficient mice housed in the two facilities proliferated and produced opposite profiles of pro-inflammatory and anti-inflammatory cytokines, compared with their controls. These findings therefore demonstrate that the effects of DAP12 deficiency on development of autoimmune disease are dramatically affected by environmental factors.

Implications for gene therapy-limiting expression of IL-2R gamma c delineate differences in signaling thresholds required for lymphocyte development and maintenance.

X-linked SCID patients are deficient in functional IL-2Rgamma(c) leading to the loss of IL-2/IL-4/IL-7/IL-9/IL-15/IL-21 signaling and a lack of NK and mature T cells. Patients treated with IL-2Rgamma(c) gene therapy have T cells develop; however, their NK cell numbers remain low, suggesting antiviral responses may be compromised. Similarly, IL-2Rgamma(c)(-/-) mice reconstituted with IL-2Rgamma(c) developed few NK cells, and reconstituted T cells exhibited defective proliferative responses suggesting incomplete recovery of IL-2Rgamma(c) signaling. Given the shift toward self-inactivating long terminal repeats with weaker promoters to control the risk of leukemia, we assessed NK and T cell numbers and function in IL-2Rgamma(c)(-/-) mice reconstituted with limiting amounts of IL-2Rgamma(c). Reconstitution resulted in lower IL-2/-15-mediated STAT5 phosphorylation and proliferation in NK and T cells. However, TCR costimulation restored cytokine-driven T cell proliferation to wild-type levels. Vector modifications that improved IL-2Rgamma(c) levels increased cytokine-induced STAT5 phosphorylation in both populations and increased NK cell proliferation demonstrating that IL-2Rgamma(c) levels are limiting. In addition, although the half-lives of both NK and T cells expressing intermediate levels of IL-2Rgamma(c) are reduced compared with wild-type cells, the reduction in NK cell half-live is much more severe than in T cells. Collectively, these data indicate different IL-2Rgamma(c) signaling thresholds for lymphocyte development and proliferation making functional monitoring imperative during gene therapy. Further, our findings suggest that IL-2Rgamma(c) reconstituted T cells may persist more efficiently than NK cells due to compensation for suboptimal IL-2Rgamma(c) signaling by the TCR.

The linker for activation of B cells (LAB)/non-T cell activation linker (NTAL) regulates triggering receptor expressed on myeloid cells (TREM)-2 signaling and macrophage inflammatory responses independently of the linker for activation of T cells.

Triggering receptor expressed on myeloid cells-2 (TREM-2) is rapidly emerging as a key regulator of the innate immune response via its regulation of macrophage inflammatory responses. Here we demonstrate that proximal TREM-2 signaling parallels other DAP12-based receptor systems in its use of Syk and Src-family kinases. However, we find that the linker for activation of T cells (LAT) is severely reduced as monocytes differentiate into macrophages and that TREM-2 exclusively uses the linker for activation of B cells (LAB encoded by the gene Lat2(-/-)) to mediate downstream signaling. LAB is required for TREM-2-mediated activation of Erk1/2 and dampens proximal TREM-2 signals through a novel LAT-independent mechanism resulting in macrophages with proinflammatory properties. Thus, Lat2(-/-) macrophages have increased TREM-2-induced proximal phosphorylation, and lipopolysaccharide stimulation of these cells leads to increased interleukin-10 (IL-10) and decreased IL-12p40 production relative to wild type cells. Together these data identify LAB as a critical, LAT-independent regulator of TREM-2 signaling and macrophage development capable of controlling subsequent inflammatory responses.

Enhancing Care for Long-Term Care Residents Approaching End-of-Life: A Mixed-Methods Study Assessing a Palliative Care Transfer Form.

BACKGROUND: Many barriers exist in providing quality end-of-life care in long-term care (LTC), including transitions of care between acute care and LTC. Transfer forms can be beneficial in ensuring resident's end-of-life care needs are coordinated between different settings. The NYGH-LTC Transfer Form is a newly developed tool created to enhance care for residents transferred from acute care back to their LTC home for end-of-life. STUDY AIM: Assess the perceived ease of use, usefulness, and care-enhancing potential of the NYGH-LTC Transfer Form by interprofessional LTC staff. METHODS: The study population included interprofessional staff members at 2 LTC homes in Toronto, Canada. Quantitative data was obtained through surveys and qualitative data was obtained through focus groups. RESULTS: There were a total of 34 participants. 79.4% of participants agreed the form was easy to use and 82.4% agreed it would improve care. Subgroup analysis demonstrated that participants with greater than 20 years experience were less likely to agree that it would improve care (p = 0.01). Qualitative analysis generated 4 themes: 1) Strengths, 2) Areas of Improvement, 3) Information Sharing, and 4) Communication. CONCLUSIONS: The NYGH-LTC Transfer Form was overall well-evaluated. The form was seen as most useful for those with less experience or less confidence in palliative care. Communication was identified as a major barrier to successful transitions of care and increased bidirectional verbal communication is needed in addition to the form.

Unique clinical and pathological features in HLA-DRB1*0401-restricted MBP 111-129-specific humanized TCR transgenic mice.

Amino acid residues 111-129 represent an immunodominant epitope of myelin basic protein (MBP) in humans with human leukocyte antigen (HLA)-DRB1*0401 allele(s). The MBP 111-129-specific T cell clone MS2-3C8 was repeatedly isolated from a patient with multiple sclerosis (MS), suggesting an involvement of MS2-3C8 T cells in the pathogenesis. To address the pathogenic potential of the MS2-3C8 T cell clone, we generated transgenic (Tg) mice expressing its T cell receptor and restriction element, HLA-DRB1*0401, to examine the pathogenic characteristics of MS2-3C8 Tg T cells by adoptive transfer into HLA-DRB1*0401 Tg mice. In addition to the ascending paralysis typical of experimental autoimmune encephalomyelitis, mice displayed dysphagia due to restriction in jaw and tongue movements and abnormal gait. In accordance with the clinical phenotype, infiltrates of MS2-3C8 Tg T cells and inflammatory lesions were predominantly located in the brainstem and the cranial nerve roots in addition to the spinal cord and spinal nerve roots. Together, these data suggest a pathogenic role of MBP-specific T cells in inflammatory demyelination within the brainstem and cranial nerve roots during the progression of MS. This notion may help to explain the clinical and pathological heterogeneity of MS.

Analysis of the linker for activation of T cells and the linker for activation of B cells in natural killer cells reveals a novel signaling cassette, dual usage in ITAM signaling, and influence on development of the Ly49 repertoire.

The linker for activation of T cells (LAT) and the linker for activation of B cells (LAB/NTAL/LAT2) are integral proteins in receptor coupling to downstream events. Both proteins are expressed in natural killer (NK) cells and LAT is phosphorylated during target cell interactions or ligation of the immunoreceptor tyrosine-based activation motif (ITAM)-coupled CD16. Regardless, Lat(-/-) mice exhibit normal natural and antibody-mediated killing. Here we place both LAT and LAB in the DAP12 pathway of NK cells. Moreover, we unveil a LAT-independent pathway that requires expression of Syk. Mice lacking either LAT or LAB have a skewed Ly49 repertoire, and activated NK cells from Lat(-/-) mice have reduced responses to the ITAM-coupled receptor NK1.1. In contrast, resting Lat(-/-) NK cells show intact NK1.1 responses, whereas NK cells without LAB are hyperactive. Elimination of both adaptors severely reduces NK1.1 signaling under both conditions. Together these data show that NK ITAMs preferentially use a signaling cassette regulated by interplay between LAT and LAB. Activation by interleukin-2 causes a shift to greater dependency on LAT due to suppression of Syk signaling. The overlapping use of multiple adaptors permits fine-tuning of NK-cell ITAM responses over the course of an immune response.

Different development of myelin basic protein agonist- and antagonist-specific human TCR transgenic T cells in the thymus and periphery.

Myelin basic protein (MBP)-specific T cells are thought to play a role in the development of multiple sclerosis. MBP residues 111-129 compose an immunodominant epitope cluster restricted by HLA-DRB1*0401. The sequence of residues 111-129 of MBP (MBP(111-129)) differs in humans (MBP122:Arg) and mice (MBP122:Lys) at aa 122. We previously found that approximately 50% of human MBP(111-129) (MBP122:Arg)-specific T cell clones, including MS2-3C8 can proliferate in response to mouse MBP(111-129) (MBP122:Lys). However, the other half of T cell clones, including HD4-1C2, cannot proliferate in response to MBP(111-129) (MBP122:Lys). We found that MBP(111-129) (MBP122:Lys) is an antagonist for HD4-1C2 TCR, therefore, MS2-3C8 and HD4-1C2 TCRs are agonist- and antagonist-specific TCRs in mice, respectively. Therefore, we examined the development of HD4-1C2 TCR and MS2-3C8 TCR transgenic (Tg) T cells in the thymus and periphery. We found that dual TCR expression exclusively facilitates the development of MBP(111-129) TCR Tg T cells in the periphery of HD4-1C2 TCR/HLA-DRB1*0401 Tg mice although it is not required for their development in the thymus. We also found that MS2-3C8 TCR Tg CD8(+) T cells develop along with MS2-3C8 TCR Tg CD4(+) T cells, and that dual TCR expression was crucial for the development of MS2-3C8 TCR Tg CD4(+) and CD8(+) T cells in the thymus and periphery, respectively. These results suggest that thymic and peripheral development of MBP-specific T cells are different; however, dual TCR expression can facilitate their development.

In vivo expression of signaling proteins in reconstituted NK cells.

Natural Killer cells are cells of the innate immune system that are important for the recognition and clearance of virally infected cells or tumors. Examination of the development and signaling of these cells has been severely hampered due to an inability to over-express proteins in these cells. We developed a novel technique to generate NK cells in vivo, all of which express a gene of interest. IL2Rgamma(c)(-/-)/Rag2(-/-) mice do not develop NK cells due to the lack of IL15 signaling. We infected bone marrow from IL2Rgamma(c)(-/-)/Rag2(-/-) mice with a retroviral construct encoding EGFP and IL2Rgamma(c) connected by an IRES. NK cells selectively developed through expression of IL2Rgamma(c) and 100% of these NK cells were found to be EGFP(+). In order to test the utilization of this method to examine the function of biologically relevant proteins, constitutively active PI3K p110gamma and p110delta isoforms were over-expressed in this system. Constitutively active p110gamma revealed profound effects on NK cell development and function in vivo while p110delta had little effect.

Emotional and sexual infidelity offline and in cyberspace.

This study investigated how men and women perceive online and offline sexual and emotional infidelity. Undergraduates from a large university in Northern Ireland participated in the study. It was found that men, when forced to decide, were more upset by sexual infidelity and women by emotional infidelity. It was also found that men were more likely to believe that women have sex when in love and that women believe that men have sex even when they are not in love. It was not, however, found that either men or women believed that having cybersex implied the other was also in love or that being in love online implied they were having cybersex. These results are explained through a social-cognitive lens.

Inhibition of thrombin-induced platelet aggregation using human single-chain Fv antibodies specific for TREM-like transcript-1.

TREM-like transcript-1 (TLT-1) is a novel platelet membrane receptor, which has been recently characterized in mice. TLT-1 is expressed exclusively in platelets and megakaryocytes, and its expression is dramatically upregulated upon platelet activation, suggesting that it plays a unique role in hemostasis and/or thrombosis. In this study we identified and characterized highly specific human monoclonal antibodies that bind to TLT-1 by screening a naïve library of single chain Fv fragments (scFvs) displayed on filamentous phage (Thomlinson I library). These scFvs detected plate-bound TLT-1, captured soluble TLT-1, and readily reacted with cell-bound TLT-1 on transfectants and primary human platelets. Most importantly, anti-TLT-1 scFvs inhibited thrombin-mediated human platelet aggregation. This inhibition was specific for thrombin-induced aggregation and was reversible with higher doses of agonist. These data are the first to demonstrate a biological role for TLT-1 and its potential as a therapeutic target. The human scFvs isolated in this study may represent novel anti-platelet therapeutic agents.

User's guide to a meta-analysis about an orthopaedic implant.

Meta-analyses can be an excellent method to summarize the existing literature of studies concerning orthopaedic implants and devices. It is important to understand how meta-analyses are conducted and to be able to evaluate whether a meta-analysis has strong methodological rigor to help with clinical decisions. This paper begins with an overview of what a meta-analysis is and why it is useful. The second section provides the important characteristics of conducting a meta-analysis. The third section will provide detail of how to interpret a meta-analysis, including topics such as the quality of the included studies, comparing the results between studies, pooling data, and how to interpret the results. The benefits and limitations are presented, along with recommendations of how to ensure future high-quality meta-analyses. Meta-analyses are useful for synthesizing the results of multiple primary studies and can provide excellent evidence for clinical decisions; however, it is important that methodological flaws are limited.

Understanding cost effectiveness: money matters?

Economic analysis is an important component that should be implemented when evaluating a new medical device. A new medical device should be both effective in improving patient outcomes as well as cost effective before it is implemented into clinical practice. This paper begins with an overview on the different methods of economic analysis including cost-minimization analysis, cost-effectiveness analysis, cost-utility analysis, and cost-benefit analysis. The second section provides a description of key design issues in cost-effectiveness analyses that are relevant to medical device trials including the perspective of the economic evaluation, the collection of cost data, how to establish clinical effectiveness in an economic analysis, how to conduct a sensitivity analysis, and when it is necessary to discount costs. It is important and necessary to consult with a health economist to ensure that the appropriate methodology is followed when conducting an economic evaluation. In conclusion, since most jurisdictions have limited funding available for health care, money definitely matters. If the cost of a medical device is unreasonable or if funding is not available, it will likely not be able to be implemented, regardless of its effectiveness. A well-conducted economic analysis will be able to answer questions on the medical device's efficacy and cost effectiveness.

Orally administered ß-glucan attenuates the Th2 response in a model of airway hypersensitivity.

ß-Glucan is a polysaccharide that can be extracted from fungal cell walls. Wellmune WGP(®), a preparation of ß-1,3/1,6-glucans, is a dietary supplement that has immunomodulating properties. Here we investigated the effect WGP had on a mouse model of asthma. OVA-induced asthma in mice is characterized by infiltration of eosinophils into the lung, production of Th2 cytokines and IgE. Daily oral administration of WGP (400 µg) significantly reduced the influx of eosinophils into the lungs of OVA-challenged mice compared to control mice. In addition, WGP inhibited pulmonary production of Th2 cytokines (IL-4, IL-5, IL-13), however serum IgE levels were unaffected by WGP treatment. These data indicate that WGP could potentially be useful as an oral supplement for some asthma patients, however, it would need to be combined with therapies that target other aspects of the disease such as IgE levels. As such, further studies that examine the potential of WGP in combination with other therapies should be explored.

Autocrine IL-10 functions as a rheostat for M1 macrophage glycolytic commitment by tuning nitric oxide production.

Inflammatory maturation of M1 macrophages by proinflammatory stimuli such as toll like receptor ligands results in profound metabolic reprogramming resulting in commitment to aerobic glycolysis as evidenced by repression of mitochondrial oxidative phosphorylation (OXPHOS) and enhanced glucose utilization. In contrast, "alternatively activated" macrophages adopt a metabolic program dominated by fatty acid-fueled OXPHOS. Despite the known importance of these developmental stages on the qualitative aspects of an inflammatory response, relatively little is know regarding the regulation of these metabolic adjustments. Here we provide evidence that the immunosuppressive cytokine IL-10 defines a metabolic regulatory loop. Our data show for the first time that lipopolysaccharide (LPS)-induced glycolytic flux controls IL-10-production via regulation of mammalian target of rapamycin (mTOR) and that autocrine IL-10 in turn regulates macrophage nitric oxide (NO) production. Genetic and pharmacological manipulation of IL-10 and nitric oxide (NO) establish that metabolically regulated autocrine IL-10 controls glycolytic commitment by limiting NO-mediated suppression of OXPHOS. Together these data support a model where autocine IL-10 production is controlled by glycolytic flux in turn regulating glycolytic commitment by preserving OXPHOS via suppression of NO. We propose that this IL-10-driven metabolic rheostat maintains metabolic equilibrium during M1 macrophage differentiation and that perturbation of this regulatory loop, either directly by exogenous cellular sources of IL-10 or indirectly via limitations in glucose availability, skews the cellular metabolic program altering the balance between inflammatory and immunosuppressive phenotypes.

Limited repertoire of HLA-DRB1*0401-restricted MBP111-129-specific T cells in HLA-DRB1*0401 Tg mice and their pathogenic potential.

Since myelin basic protein (MBP)111-129 is an immunodominant epitope in humans carrying HLA-DRB1*0401, we investigated the encephalitogenic potential of HLA-DRB1*0401-restricted MBP111-129-specific T cells using HLA-DRB1*0401/DRA*0101 transgenic (Tg) mice. Although we could not detect the primary recall response to MBP111-129 peptide after immunization of HLA-DRB1*0401/DRA*0101 Tg mice with human MBP, V beta 10(+) and V beta 2(+) HLA-DRB1*0401-restricted MBP111-129-specific T cells proliferated after restimulation of the lymph node cells with human MBP111-129 in vitro. The V beta 2(+) T cell line recognized only human MBP111-129 in the context of HLA-DRB1*0401, while the V beta 10(+) T cell line recognized both the human and murine MBP111-129 epitopes. Therefore, we examined the encephalitogenic potential of the V beta 10(+) T cell line in HLA-DRB1*0401/DRA*0101 Tg mice by adoptive transfer experiments. The V beta 10(+) T cell line induced mild EAE and inflammatory lesions were observed in the spinal cord and the brainstem. In the spinal cord, the inflammation was observed in the peripheral nerve roots as well as in the CNS. These data suggest the pathogenic potential of HLA-DRB1*0401-restricted MBP111-129-specific T cells in humans.