Evasins: Tick Salivary Proteins that Inhibit Mammalian Chemokines.

Ticks are hematophagous arachnids that parasitize mammals and other hosts, feeding on their blood. Ticks secrete numerous salivary factors that enhance host blood flow or suppress the host inflammatory response. The recruitment of leukocytes, a hallmark of inflammation, is regulated by chemokines, which activate chemokine receptors on the leukocytes. Ticks target this process by secreting glycoproteins called Evasins, which bind to chemokines and prevent leukocyte recruitment. This review describes the recent discovery of numerous Evasins produced by ticks, their classification into two structural and functional classes, and the efficacy of Evasins in animal models of inflammatory diseases. The review also proposes a standard nomenclature system for Evasins and discusses the potential of repurposing or engineering Evasins as therapeutic anti-inflammatory agents.

Adult retrospective report of child abuse and prospective indicators of childhood harm: a population birth cohort study.

BACKGROUND: We aim to determine whether adult retrospective report of child abuse is associated with greater risk of prospectively assessed harmful environments in childhood. We assessed possible recall basis by adult depression status. METHODS: At 45 years, participants of the 1958 British birth cohort (N = 9308) reported a range of abuse types (by 16 years). Prospective data, ages 7-16 years, were obtained for impoverished upbringing, hazardous conditions, anti-social behaviours and 16 years poor parent-child relationships. We estimated associations between retrospective report of child abuse and prospectively measured harm using (i) odds ratios (ORs, 95% confidence intervals) and (ii) positive predictive values (PPVs). PPVs were calculated stratified by adult depression status. RESULTS: Prevalence of retrospectively reported abuse ranged from 10.7% (psychological) to 1.60% (sexual) and 14.8% reported ≥ 1 type; prospectively recorded harm ranged from 10% (hazardous conditions/poor parent-child relationships) to 20% (anti-social behaviours). Adults retrospectively reporting abuse were more likely to have had harmful childhood environments: 52.4% had ≥ 1 indicator of harm (vs. 35.6% among others); ORsex-adjusted for poor relationships with parents was 2.98 (2.50, 3.54). For retrospectively reported (vs. none) abuse, there was a trend of increasing relative risk ratio with number of harms, from 1.75 (1.50, 2.03) for 1 to 4.68 (3.39, 6.45) for 3/4 childhood harms. The PPV of ≥ 1 prospectively recorded harm did not differ between depressed (0.58 (0.52, 0.64)) and non-depressed (0.58 (0.55, 0.61)) groups. CONCLUSIONS: In a population cohort, adult retrospective report of child abuse was associated with several harms, prospectively measured from childhood to adolescence, providing support for the validity of retrospective report-based research. Findings suggest retrospectively reported child abuse is not biased by depression in adulthood.

A Bidirectional Mendelian Randomization Study to evaluate the causal role of reduced blood vitamin D levels with type 2 diabetes risk in South Asians and Europeans.

CONTEXT: Multiple observational studies have reported an inverse relationship between 25-hydroxyvitamin D concentrations (25(OH)D) and type 2 diabetes (T2D). However, the results of short- and long-term interventional trials concerning the relationship between 25(OH)D and T2D risk have been inconsistent. OBJECTIVES AND METHODS: To evaluate the causal role of reduced blood 25(OH)D in T2D, here we have performed a bidirectional Mendelian randomization study using 59,890 individuals (5,862 T2D cases and 54,028 controls) from European and Asian Indian ancestries. We used six known SNPs, including three T2D SNPs and three vitamin D pathway SNPs, as a genetic instrument to evaluate the causality and direction of the association between T2D and circulating 25(OH)D concentration. RESULTS: Results of the combined meta-analysis of eight participating studies showed that a composite score of three T2D SNPs would significantly increase T2D risk by an odds ratio (OR) of 1.24, p = 1.82 × 10-32; Z score 11.86, which, however, had no significant association with 25(OH)D status (Beta -0.02nmol/L ± SE 0.01nmol/L; p = 0.83; Z score -0.21). Likewise, the genetically instrumented composite score of 25(OH)D lowering alleles significantly decreased 25(OH)D concentrations (-2.1nmol/L ± SE 0.1nmol/L, p = 7.92 × 10-78; Z score -18.68) but was not associated with increased risk for T2D (OR 1.00, p = 0.12; Z score 1.54). However, using 25(OH)D synthesis SNP (DHCR7; rs12785878) as an individual genetic instrument, a per allele reduction of 25(OH)D concentration (-4.2nmol/L ± SE 0.3nmol/L) was predicted to increase T2D risk by 5%, p = 0.004; Z score 2.84. This effect, however, was not seen in other 25(OH)D SNPs (GC rs2282679, CYP2R1 rs12794714) when used as an individual instrument. CONCLUSION: Our new data on this bidirectional Mendelian randomization study suggests that genetically instrumented T2D risk does not cause changes in 25(OH)D levels. However, genetically regulated 25(OH)D deficiency due to vitamin D synthesis gene (DHCR7) may influence the risk of T2D.

A cross-country qualitative study on contraceptive method mix: contraceptive decisionmaking among youth.

BACKGROUND: Youth ages 15 to 24, who comprise a large portion of sub-Saharan Africa, face a higher burden of unmet contraceptive need than adults. Despite increased international and national commitments to improving young people's access to contraception, significant barriers impede their access to a full range of methods. To further explore these barriers among youth in Kenya, Nigeria, and Uganda, we conducted a qualitative study to capture the challenges that affect contraceptive method decisionmaking and complicate youth access to the full method mix. METHODS: To understand factors that impact young people's contraceptive decisionmaking process across all three countries, we conducted a total of 35 focus group discussions with 171 youth ages 15 to 24 and 130 in-depth interviews with key stakeholders working in youth family planning. Questionnaires aligned with the High Impact Practices in Family Planning's elements of adolescent-friendly contraceptive services. Data were coded with MAXQDA and analyzed using a framework for contraceptive decisionmaking to identify relevant patterns and themes. RESULTS: In all three countries, youth reported that condoms are the most commonly sought contraceptive method because they are easiest to access and because youth have limited knowledge of other methods. Youth from diverse settings shared uncertainty and concern about the safety and side effects of many methods other than condoms, complicating their ability to take full advantage of other available methods. While most youth in Kenya, Nigeria, and Uganda reported at least moderate confidence in obtaining the information needed to help choose a method, and only a few youth reported that they are completely unable to access contraceptives, other barriers still present a major deterrent for youth, including cost, inconvenient facility hours and long wait times, and stigma from family, community members, and providers. CONCLUSIONS: Young people's ability to fully exercise their method choice remains limited despite availability of services, leading them to take the path of least resistance. Program implementers and policymakers should consider the diverse and often interconnected barriers that youth face in attempting to enjoy the benefits of a full spectrum of contraceptive methods and design multi-level interventions to mitigate such barriers.

Despite increased international and national commitments to improving young people's access to contraception, youth ages 15 to 24 face significant barriers to accessing a full range of contraceptive methods. This study conducted in-depth interviews with key stakeholders and focus group discussions with youth in Kenya, Nigeria, and Uganda to understand what factors impact youth's decision to use or not use certain contraceptive methods. In all three countries, youth reported that condoms are the most commonly sought contraceptive method because they are easiest to access and because youth have limited knowledge of other methods. Youth from diverse settings shared uncertainty and concern about the safety and side effects of many methods other than condoms. While most youth in Kenya, Nigeria, and Uganda reported at least moderate confidence in obtaining the information needed to help choose a method, other barriers like cost, inconvenient facility hours and long wait times, and stigma from family, community members, and providers still present a major deterrent for youth who want information on contraceptive methods. Program implementers and policymakers should consider the diverse and often interconnected barriers that youth face in attempting to enjoy the benefits of a full spectrum of contraceptive methods and design multi-level interventions to mitigate such barriers.

Exploring the links between unhealthy eating behaviour and heavy alcohol use in the social, emotional and cultural lives of young adults (aged 18-25): A qualitative research study.

Alcohol use peaks in early adulthood and can contribute both directly and indirectly to unhealthy weight gain. This is the first qualitative study to explore the links between unhealthy eating behaviour and heavy alcohol use in the social, emotional and cultural lives of young adults. We conducted 45 in-depth interviews with 18-25-year-olds in North-East England to inform development of a dual-focused intervention to reduce health risk due to excess weight gain and alcohol use. Data were analysed thematically, following the principles of constant comparison, resulting in three intersecting themes: (1) how food and alcohol consumption currently link together for this population group; (2) influences upon linked eating and drinking behaviours and (3) young adults' feelings and concerns about linked eating and drinking behaviours. Socio-cultural, physical and emotional links between food and alcohol consumption were an unquestioned norm among young adults. Eating patterns linked to alcohol use were not tied only to hunger, but also to sociability, traditions and identity. Young adults conceptualised and calculated risks to weight, appearance and social status, rather than to long-term health. This study is the first to evidence the deeply interconnected nature of food and alcohol consumption for many young adults. Findings have important implications for intervention development, UK public health policy and practice, and point to a need for similar research in other countries.

Phenome-wide association analysis of LDL-cholesterol lowering genetic variants in PCSK9.

BACKGROUND: We characterised the phenotypic consequence of genetic variation at the PCSK9 locus and compared findings with recent trials of pharmacological inhibitors of PCSK9. METHODS: Published and individual participant level data (300,000+ participants) were combined to construct a weighted PCSK9 gene-centric score (GS). Seventeen randomized placebo controlled PCSK9 inhibitor trials were included, providing data on 79,578 participants. Results were scaled to a one mmol/L lower LDL-C concentration. RESULTS: The PCSK9 GS (comprising 4 SNPs) associations with plasma lipid and apolipoprotein levels were consistent in direction with treatment effects. The GS odds ratio (OR) for myocardial infarction (MI) was 0.53 (95% CI 0.42; 0.68), compared to a PCSK9 inhibitor effect of 0.90 (95% CI 0.86; 0.93). For ischemic stroke ORs were 0.84 (95% CI 0.57; 1.22) for the GS, compared to 0.85 (95% CI 0.78; 0.93) in the drug trials. ORs with type 2 diabetes mellitus (T2DM) were 1.29 (95% CI 1.11; 1.50) for the GS, as compared to 1.00 (95% CI 0.96; 1.04) for incident T2DM in PCSK9 inhibitor trials. No genetic associations were observed for cancer, heart failure, atrial fibrillation, chronic obstructive pulmonary disease, or Alzheimer's disease - outcomes for which large-scale trial data were unavailable. CONCLUSIONS: Genetic variation at the PCSK9 locus recapitulates the effects of therapeutic inhibition of PCSK9 on major blood lipid fractions and MI. While indicating an increased risk of T2DM, no other possible safety concerns were shown; although precision was moderate.

Obesity and depressive symptoms in mid-life: a population-based cohort study.

BACKGROUND: Obesity and depression are both highly prevalent public health disorders and evidence on their relationship is inconsistent. This study examined whether depressive symptoms are associated with current obesity, and further, whether obesity in turn is associated with an increased odds of depressive symptoms five years later after accounting for potential lifestyle confounders and depressive symptoms at baseline. METHODS: Data were obtained from the 1958 British birth cohort (N = 9217 for cross-sectional and 7340 for prospective analysis). Clinical Interview Schedule-Revised and Mental Health Inventory-5 were used for screening depressive symptoms at ages 45 and 50 years, respectively. General and central obesity were defined using measurements of body mass index (BMI) and waist circumference (WC) at 45 years, respectively. RESULTS: There was a cross-sectional association between depressive symptoms and obesity: participants with ≥2 depressive symptoms had 31% (95%CI 11% to 55%) higher odds of general and 26% higher odds of central obesity (95%CI 8% to 47%). In prospective analyses, both general and central obesity were associated with higher odds of depressive symptoms five years later among women but not in men (Pinteraction < 0.01). After adjustment for depressive symptoms at baseline, sociodemographic and lifestyle factors, women with general obesity had 38% (95% CI 7% to 77%) and women with central obesity 34% (95%CI 9% to 65%) higher odds of depression compared to others. CONCLUSIONS: Depressive symptoms are associated with concurrent obesity and related lifestyle factors among women and men in mid-life. Our study suggests that obesity in turn affects long-term risk of depressive symptoms in women but not in men, independently of concurrent associations, providing an important target group for the implementation of preventative strategies.

Anti-bacterial Monoclonal Antibodies.

The failing efficacy of antibiotics and the high mortality rate among high-risk patients calls for new treatment modalities for bacterial infections. Due to the vastly divergent pathogenesis of human pathogens, each microbe requires a tailored approach. The main modes of action of anti-bacterial antibodies are virulence factor neutralization, complement-mediated bacterial lysis and enhancement of opsonophagocytic uptake and killing (OPK). Gram-positive bacteria cannot be lysed by complement and their pathogenesis often involves secreted toxins, therefore typically toxin-neutralization and OPK activity are required to prevent and ameliorate disease. In fact, the success stories in terms of approved products, in the anti-bacterial mAb field are based on toxin neutralization (Bacillus anthracis, Clostridium difficile). In contrast, Gram-negative bacteria are vulnerable to antibody-dependent complement-mediated lysis, while their pathogenesis rarely relies on secreted exotoxins, and involves the pro-inflammatory endotoxin (lipopolysaccharide). Given the complexity of bacterial pathogenesis, antibody therapeutics are expected to be most efficient upon targeting more than one virulence factor and/or combining different modes of action. The improved understanding of bacterial pathogenesis combined with the versatility and maturity of antibody discovery technologies available today are pivotal for the design of novel anti-bacterial therapeutics. The intensified research generating promising proof-of-concept data, and the increasing number of clinical programs with anti-bacterial mAbs, indicate that the field is ready to fulfill its promise in the coming years.

International Union of Basic and Clinical Pharmacology. [corrected]. LXXXIX. Update on the extended family of chemokine receptors and introducing a new nomenclature for atypical chemokine receptors.

Sixteen years ago, the Nomenclature Committee of the International Union of Pharmacology approved a system for naming human seven-transmembrane (7TM) G protein-coupled chemokine receptors, the large family of leukocyte chemoattractant receptors that regulates immune system development and function, in large part by mediating leukocyte trafficking. This was announced in Pharmacological Reviews in a major overview of the first decade of research in this field [Murphy PM, Baggiolini M, Charo IF, Hébert CA, Horuk R, Matsushima K, Miller LH, Oppenheim JJ, and Power CA (2000) Pharmacol Rev 52:145-176]. Since then, several new receptors have been discovered, and major advances have been made for the others in many areas, including structural biology, signal transduction mechanisms, biology, and pharmacology. New and diverse roles have been identified in infection, immunity, inflammation, development, cancer, and other areas. The first two drugs acting at chemokine receptors have been approved by the U.S. Food and Drug Administration (FDA), maraviroc targeting CCR5 in human immunodeficiency virus (HIV)/AIDS, and plerixafor targeting CXCR4 for stem cell mobilization for transplantation in cancer, and other candidates are now undergoing pivotal clinical trials for diverse disease indications. In addition, a subfamily of atypical chemokine receptors has emerged that may signal through arrestins instead of G proteins to act as chemokine scavengers, and many microbial and invertebrate G protein-coupled chemokine receptors and soluble chemokine-binding proteins have been described. Here, we review this extended family of chemokine receptors and chemokine-binding proteins at the basic, translational, and clinical levels, including an update on drug development. We also introduce a new nomenclature for atypical chemokine receptors with the stem ACKR (atypical chemokine receptor) approved by the Nomenclature Committee of the International Union of Pharmacology and the Human Genome Nomenclature Committee.

Genetic Evidence for Causal Relationships Between Maternal Obesity-Related Traits and Birth Weight.

IMPORTANCE: Neonates born to overweight or obese women are larger and at higher risk of birth complications. Many maternal obesity-related traits are observationally associated with birth weight, but the causal nature of these associations is uncertain. OBJECTIVE: To test for genetic evidence of causal associations of maternal body mass index (BMI) and related traits with birth weight. DESIGN, SETTING, AND PARTICIPANTS: Mendelian randomization to test whether maternal BMI and obesity-related traits are potentially causally related to offspring birth weight. Data from 30,487 women in 18 studies were analyzed. Participants were of European ancestry from population- or community-based studies in Europe, North America, or Australia and were part of the Early Growth Genetics Consortium. Live, term, singleton offspring born between 1929 and 2013 were included. EXPOSURES: Genetic scores for BMI, fasting glucose level, type 2 diabetes, systolic blood pressure (SBP), triglyceride level, high-density lipoprotein cholesterol (HDL-C) level, vitamin D status, and adiponectin level. MAIN OUTCOME AND MEASURE: Offspring birth weight from 18 studies. RESULTS: Among the 30,487 newborns the mean birth weight in the various cohorts ranged from 3325 g to 3679 g. The maternal genetic score for BMI was associated with a 2-g (95% CI, 0 to 3 g) higher offspring birth weight per maternal BMI-raising allele (P = .008). The maternal genetic scores for fasting glucose and SBP were also associated with birth weight with effect sizes of 8 g (95% CI, 6 to 10 g) per glucose-raising allele (P = 7 × 10(-14)) and -4 g (95% CI, -6 to -2 g) per SBP-raising allele (P = 1×10(-5)), respectively. A 1-SD ( ≈ 4 points) genetically higher maternal BMI was associated with a 55-g higher offspring birth weight (95% CI, 17 to 93 g). A 1-SD ( ≈ 7.2 mg/dL) genetically higher maternal fasting glucose concentration was associated with 114-g higher offspring birth weight (95% CI, 80 to 147 g). However, a 1-SD ( ≈ 10 mm Hg) genetically higher maternal SBP was associated with a 208-g lower offspring birth weight (95% CI, -394 to -21 g). For BMI and fasting glucose, genetic associations were consistent with the observational associations, but for systolic blood pressure, the genetic and observational associations were in opposite directions. CONCLUSIONS AND RELEVANCE: In this mendelian randomization study, genetically elevated maternal BMI and blood glucose levels were potentially causally associated with higher offspring birth weight, whereas genetically elevated maternal SBP was potentially causally related to lower birth weight. If replicated, these findings may have implications for counseling and managing pregnancies to avoid adverse weight-related birth outcomes.

A genome-wide approach to children's aggressive behavior: The EAGLE consortium.

Individual differences in aggressive behavior emerge in early childhood and predict persisting behavioral problems and disorders. Studies of antisocial and severe aggression in adulthood indicate substantial underlying biology. However, little attention has been given to genome-wide approaches of aggressive behavior in children. We analyzed data from nine population-based studies and assessed aggressive behavior using well-validated parent-reported questionnaires. This is the largest sample exploring children's aggressive behavior to date (N = 18,988), with measures in two developmental stages (N = 15,668 early childhood and N = 16,311 middle childhood/early adolescence). First, we estimated the additive genetic variance of children's aggressive behavior based on genome-wide SNP information, using genome-wide complex trait analysis (GCTA). Second, genetic associations within each study were assessed using a quasi-Poisson regression approach, capturing the highly right-skewed distribution of aggressive behavior. Third, we performed meta-analyses of genome-wide associations for both the total age-mixed sample and the two developmental stages. Finally, we performed a gene-based test using the summary statistics of the total sample. GCTA quantified variance tagged by common SNPs (10-54%). The meta-analysis of the total sample identified one region in chromosome 2 (2p12) at near genome-wide significance (top SNP rs11126630, P = 5.30 × 10(-8) ). The separate meta-analyses of the two developmental stages revealed suggestive evidence of association at the same locus. The gene-based analysis indicated association of variation within AVPR1A with aggressive behavior. We conclude that common variants at 2p12 show suggestive evidence for association with childhood aggression. Replication of these initial findings is needed, and further studies should clarify its biological meaning. © 2015 Wiley Periodicals, Inc.

Identification of the pharmacophore of the CC chemokine-binding proteins Evasin-1 and -4 using phage display.

To elucidate the ligand-binding surface of the CC chemokine-binding proteins Evasin-1 and Evasin-4, produced by the tick Rhipicephalus sanguineus, we sought to identify the key determinants responsible for their different chemokine selectivities by expressing Evasin mutants using phage display. We first designed alanine mutants based on the Evasin-1·CCL3 complex structure and an in silico model of Evasin-4 bound to CCL3. The mutants were displayed on M13 phage particles, and binding to chemokine was assessed by ELISA. Selected variants were then produced as purified proteins and characterized by surface plasmon resonance analysis and inhibition of chemotaxis. The method was validated by confirming the importance of Phe-14 and Trp-89 to the inhibitory properties of Evasin-1 and led to the identification of a third crucial residue, Asn-88. Two amino acids, Glu-16 and Tyr-19, were identified as key residues for binding and inhibition of Evasin-4. In a parallel approach, we identified one clone (Y28Q/N60D) that showed a clear reduction in binding to CCL3, CCL5, and CCL8. It therefore appears that Evasin-1 and -4 use different pharmacophores to bind CC chemokines, with the principal binding occurring through the C terminus of Evasin-1, but through the N-terminal region of Evasin-4. However, both proteins appear to target chemokine N termini, presumably because these domains are key to receptor signaling. The results also suggest that phage display may offer a useful approach for rapid investigation of the pharmacophores of small inhibitory binding proteins.

Targeting chemokines: Pathogens can, why can't we?

Chemoattractant cytokines, or chemokines, are the largest sub-family of cytokines. About 50 distinct chemokines have been identified in humans. Their principal role is to stimulate the directional migration of leukocytes, which they achieve through activation of their receptors, following immobilization on cell surface glycosaminoglycans (GAGs). Chemokine receptors belong to the G protein-coupled 7-transmembrane receptor family, and hence their identification brought great promise to the pharmaceutical industry, since this receptor class is the target for a large percentage of marketed drugs. Unfortunately, the development of potent and efficacious inhibitors of chemokine receptors has not lived up to the early expectations. Several approaches to targeting this system will be described here, which have been instrumental in establishing paradigms in chemokine biology. Whilst drug discovery programs have not yet elucidated how to make successful drugs targeting the chemokine system, it is now known that certain parasites have evolved anti-chemokine strategies in order to remain undetected by their hosts. What can we learn from them?

Genetic impacts on DNA methylation help elucidate regulatory genomic processes.

BACKGROUND: Pinpointing genetic impacts on DNA methylation can improve our understanding of pathways that underlie gene regulation and disease risk. RESULTS: We report heritability and methylation quantitative trait locus (meQTL) analysis at 724,499 CpGs profiled with the Illumina Infinium MethylationEPIC array in 2358 blood samples from three UK cohorts. Methylation levels at 34.2% of CpGs are affected by SNPs, and 98% of effects are cis-acting or within 1 Mbp of the tested CpG. Our results are consistent with meQTL analyses based on the former Illumina Infinium HumanMethylation450 array. Both SNPs and CpGs with meQTLs are overrepresented in enhancers, which have improved coverage on this platform compared to previous approaches. Co-localisation analyses across genetic effects on DNA methylation and 56 human traits identify 1520 co-localisations across 1325 unique CpGs and 34 phenotypes, including in disease-relevant genes, such as USP1 and DOCK7 (total cholesterol levels), and ICOSLG (inflammatory bowel disease). Enrichment analysis of meQTLs and integration with expression QTLs give insights into mechanisms underlying cis-meQTLs (e.g. through disruption of transcription factor binding sites for CTCF and SMC3) and trans-meQTLs (e.g. through regulating the expression of ACD and SENP7 which can modulate DNA methylation at distal sites). CONCLUSIONS: Our findings improve the characterisation of the mechanisms underlying DNA methylation variability and are informative for prioritisation of GWAS variants for functional follow-ups. The MeQTL EPIC Database and viewer are available online at https://epicmeqtl.kcl.ac.uk .

Serological status of Canadian cattle for brucellosis, anaplasmosis, and bluetongue in 2007-2008.

A national bovine serological survey was conducted to confirm that the prevalence of brucellosis, bluetongue, and anaplasmosis does not exceed 0.02% (95% confidence) in live cattle in Canada. Sampling consisted of a systematic random sample of 15 482 adult cattle slaughtered in federally inspected abattoirs, stratified by province. Samples were tested to detect antibodies for brucellosis, bluetongue, and anaplasmosis. All samples were negative for brucellosis. Three samples were seroreactors to bluetongue, 2 of which originated from the Okanagan Valley in British Columbia and 1 from Ontario, which after follow-up, was considered an atypical result. A total of 244 samples were seroreactors to Anaplasma and follow-up identified infection in Saskatchewan, Manitoba, and Quebec. In conclusion, the Canadian cattle population remains free of brucellosis and free of bluetongue outside the Okanagan Valley. Canada is no longer free of anaplasmosis and will be unable to claim freedom until eradication measures are completed.

RésuméStatut sérologique des bovins canadiens à l'égard de la brucellose, l'anaplasmose et la fièvre catarrhale du mouton en 2007­2008. L'enquête sérologique sur les bovins a été menée à l'échelle nationale afin de confirmer que la brucellose, la fièvre catarrhale du mouton et l'anaplasmose demeurent à une prévalence inférieure à 0,02 % (intervalle de confiance de 95 %) dans le cheptel bovin canadien. Un échantillonnage systématique de 15 482 bovins adultes a été effectué dans les abattoirs sous inspection fédérale, en stratifiant par province. Tous les échantillons se sont avérés négatifs en sérologie pour la brucellose. Une réaction sérologique a été identifiée pour la fièvre catarrhale du mouton chez trois bovins, dont deux provenaient de la vallée de l'Okanagan en Colombie-Britanique. L'autre réacteur provenait d'une ferme d'Ontario, où, après investigation, les résultats ont été considérés atypiques. Une réaction sérologique à l'anaplasmose a été détectée dans 244 échantillons. Les investigations ont permis d'identifier des fermes infectées en Saskatchewan, au Manitoba et au Québec. Le cheptel bovin canadien demeure donc indemne de la brucellose, et de la fièvre catarrhale du mouton à l'exclusion des bovins la vallée de l'Okanagan en Colombie-Britannique. Le Canada n'est plus considéré comme étant indemne de l'anaplasmose et ne pourra réclamer ce statut tant que l'éradication ne sera pas terminée.(Traduit par les auteurs).

Characterization of the chemokine CXCL11-heparin interaction suggests two different affinities for glycosaminoglycans.

Chemokines orchestrate the migration of leukocytes in the context of homeostasis and inflammation. In addition to interactions of chemokines with receptors on migrating cells, these processes require interactions of chemokines with glycosaminoglycans (GAGs) for cell surface localization. Most chemokines are basic proteins with Arg/Lys/His residue clusters functioning as recognition epitopes for GAGs. In this study we characterized the GAG-binding epitopes of the chemokine I-TAC/CXCL11. Four separate clusters of basic residues were mutated to alanine and tested for their ability to bind to GAGs in vitro and to activate the receptor, CXCR3. Mutation of a set of basic residues in the C-terminal helix (the 50s cluster, (57)KSKQAR(62)) along with Lys(17), significantly impaired heparin binding in vitro, identifying these residues as components of the dominant epitope. However, this GAG mutant retained nearly wild type receptor binding affinity, and its ability to induce cell migration in vitro was only mildly perturbed. Nevertheless, the mutant was unable to induce cell migration in vivo, establishing a requirement of CXCL11 for GAG binding for in vivo function. These studies also led to some interesting findings. First, CXCL11 exhibits conformational heterogeneity, as evidenced by the doubling of peaks in its HSQC spectra. Second, it exhibits more than one affinity state for both heparin and CXCR3, which may be related to its structural plasticity. Finally, although the binding affinities of chemokines for GAGs are typically weaker than interactions with receptors, the high affinity GAG binding state of CXCL11 is comparable with typical receptor binding affinities, suggesting some unique properties of this chemokine.

A role for CCR4 in development of mature circulating cutaneous T helper memory cell populations.

Expression of the chemokine receptor CCR4 is strongly associated with trafficking of specialized cutaneous memory T helper (Th) lymphocytes to the skin. However, it is unknown whether CCR4 itself participates in the development of cutaneous Th populations. We have addressed this issue via competitive bone marrow (BM) reconstitution assays; equal numbers of BM cells from CCR4(+/+) and CCR4(-/-) donors were allowed to develop side-by-side within RAG-1(-/-) hosts. Cells from both donor types developed equally well into B cells, naive CD8 T cells, naive CD4 T cells, interferon-gamma(+) Th1 cells, and interleukin-4(+) Th2 cells. In marked contrast, circulating cutaneous memory Th cells (i.e., E-selectin ligand(+) [E-lig(+)]) were more than fourfold more likely to be derived from CCR4(+/+) donors than from CCR4(-/-) donors. Most of this effect resides within the CD103(+) subset of the E-lig(+) Th population, in which donor CCR4(+/+) cells can outnumber CCR4(-/-) cells by >12-fold. No similar effect was observed for alpha4beta7(+) intestinal memory Th cells or CD103(+)/E-lig(-) Th cells. We conclude that CCR4 expression provides a competitive advantage to cutaneous Th cells, either by participating in their development from naive Th cells, or by preferentially maintaining them within the memory population over time.

Child maltreatment, early life socioeconomic disadvantage and all-cause mortality in mid-adulthood: findings from a prospective British birth cohort.

OBJECTIVES: Early-life adversities (ELAs) such as child maltreatment (neglect and abuse) and socioeconomic disadvantage have been associated with adult mortality. However, evidence is sparse for specific types of ELA. We aimed to establish whether specific ELAs (ie, different types of child maltreatment and socioeconomic disadvantage) were associated independently with all-cause mortality in mid-adulthood and to examine potential intermediary pathways. DESIGN: Prospective cohort study. SETTING: 1958 British birth cohort: a longitudinal, population-based sample of individuals born in Great Britain during a single week in March 1958. PARTICIPANTS: 9310 males and females with data on child maltreatment and mortality (44/45-58 years). OUTCOME MEASURES: Mortality follow-up from 2002/2003 to 2016 when participants were aged 44/45-58 years. Death was ascertained via the NHS Central Register (N=296) or cohort maintenance activities (N=16). RESULTS: Prevalence of ELAs ranged from 1.6% (sexual abuse) to 11% (psychological abuse). Several, but not all, ELAs were associated with increased risk of premature death, independent of covariates and other adversities; adjusted HRs were 2.64 (95% CI 1.52 to 4.59) for sexual abuse, 1.93 (95% CI 1.45 to 2.58) for socioeconomic disadvantage, 1.73 (95% CI 1.11 to 2.71) for physical abuse and 1.43 (95% CI 1.03 to 1.98) for neglect. After adjustment for covariates and other adversities, no associations with mortality were observed for psychological and witnessing abuse. Regarding potential intermediaries (including adult socioeconomic factors, behaviours, adiposity, mental health and cardiometabolic markers), most associations attenuated after accounting for adult health behaviours (particularly smoking). In addition, early-life socioeconomic disadvantage and neglect associations attenuated after accounting for adult socioeconomic factors. The association for sexual abuse and premature mortality was largely unaffected by potential intermediaries. CONCLUSIONS: Associations with premature mortality varied by type of ELA: associations for sexual and physical abuse, neglect and socioeconomic disadvantage were independent of each other. Different types of ELAs could influence premature mortality via different pathways; this requires further research.

Discovery of a novel series of CXCR3 antagonists.

The discovery of a novel series of CXCR3 antagonists is described. Starting from an HTS positive, iterative optimization gave potent compounds (IC(50) 15 nM in a chemotaxis assay). The strategy employed to improve the metabolic stability of these derivatives is described.

David vs. Goliath: The Structure, Function, and Clinical Prospects of Antibody Fragments.

Since the licensing of the first monoclonal antibody therapy in 1986, monoclonal antibodies have become the largest class of biopharmaceuticals with over 80 antibodies currently approved for a variety of disease indications. The development of smaller, antigen binding antibody fragments, derived from conventional antibodies or produced recombinantly, has been growing at a fast pace. Antibody fragments can be used on their own or linked to other molecules to generate numerous possibilities for bispecific, multi-specific, multimeric, or multifunctional molecules, and to achieve a variety of biological effects. They offer several advantages over full-length monoclonal antibodies, particularly a lower cost of goods, and because of their small size they can penetrate tissues, access challenging epitopes, and have potentially reduced immunogenicity. In this review, we will discuss the structure, production, and mechanism of action of EMA/FDA-approved fragments and of those in clinical and pre-clinical development. We will also discuss current topics of interest surrounding the potential use of antibody fragments for intracellular targeting and blood-brain barrier (BBB) penetration.