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HLA class I (HLA-I) allotypes vary widely in their dependence on tapasin (TAPBP), an integral component of the peptide-loading complex, to present peptides on the cell surface. We identified two single-nucleotide polymorphisms that regulate TAPBP messenger RNA (mRNA) expression in Africans, rs111686073 (G/C) and rs59097151 (A/G), located in an AP-2α transcription factor binding site and a microRNA (miR)-4486 binding site, respectively. rs111686073G and rs59097151A induced significantly higher TAPBP mRNA expression relative to the alternative alleles due to higher affinity for AP-2α and abrogation of miR-4486 binding, respectively. These variants associated with lower Plasmodium falciparum parasite prevalence and lower incidence of clinical malaria specifically among individuals carrying tapasin-dependent HLA-I allotypes, presumably by augmenting peptide loading, whereas tapasin-independent allotypes associated with relative protection, regardless of imputed TAPBP mRNA expression levels. Thus, an attenuated course of malaria may occur through enhanced breadth and/or magnitude of antigen presentation, an important consideration when evaluating vaccine efficacy.

Incluye índice temático. Resumen basado en el de la publicación El desarrollo de un curriculum es una especie de planificación sistemática de lo que se enseña y se aprende en las escuelas tal y como se refleja en los cursos de estudio y en los programas escolares. Un curriculum se centra en lo que se va a enseñar y cuándo, dejando a los profesionales de la enseñanza decisiones sobre cómo debería realizarse esta enseñanza. Repartidos en veinte capítulos, se tratan, entre otros, los siguientes temas: La aplicación de la estrategia del Aprendizaje Basado en Problemas o Problem Based Learning (PBL); El desarrollo de un modelo de situación formativa para enseñar ciencia y tecnología, que pretende ser tomado como base a las decisiones de los profesores para lograr la calidad en la enseñanza; La discusión de cinco modelos de desarrollo curricular basados en diferentes conceptos de experiencia de aprendizaje; Las habilidades para realizar presentaciones orales; El estudio de cómo los maestros de Primaria aprenden a participar en el diseño de materiales curriculares para ciencia; Las razones para desarrollar un curriculum centrado en el aprendizaje en la enseñanza superior; La mejora del conocimiento académico de los estudiantes y el incremento de su competencia social; El efecto del uso de estructuras de texto expositivas como estrategia en la habilidad de resumir; El desarrollo curricular en ambientes online; La evaluación de la reforma curricular en la Educación Secundaria turca; La importancia del desarrollo social y emocional en el éxito; entre otros. SC Biblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín 5 -3 Planta; 28014 Madrid; Tel. +34917748000; biblioteca@mecd.es USA

Killer cell immunoglobulin-like receptors (KIRs) are expressed predominantly on natural killer cells, where they play a key role in the regulation of innate immune responses. Recent studies show that inhibitory KIRs can also affect adaptive T cell-mediated immunity. In mice and in human T cells in vitro, inhibitory KIR ligation enhanced CD8+ T cell survival. To investigate the clinical relevance of these observations, we conducted an extensive immunogenetic analysis of multiple independent cohorts of HIV-1-, hepatitis C virus (HCV)-, and human T cell leukemia virus type 1 (HTLV-1)-infected individuals in conjunction with in vitro assays of T cell survival, analysis of ex vivo KIR expression, and mathematical modeling of host-virus dynamics. Our data suggest that functional engagement of inhibitory KIRs enhances the CD8+ T cell response against HIV-1, HCV, and HTLV-1 and is a significant determinant of clinical outcome in all three viral infections.

Made available in DSpace on 2019-10-06T16:55:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01 Wisconsin Turfgrass Association National Institutes of Health Wellcome Trust Institute for National Strategic Studies Leukemia and Lymphoma Research Seventh Framework Programme Horizon 2020 Medical Research Council Canada National Institute on Drug Abuse National Institute of Child Health and Human Development Killer cell immunoglobulin-like receptors (KIRs) are expressed predominantly on natural killer cells, where they play a key role in the regulation of innate immune responses. Recent studies show that inhibitory KIRs can also affect adaptive T cell–mediated immunity. In mice and in human T cells in vitro, inhibitory KIR ligation enhanced CD8+ T cell survival. To investigate the clinical relevance of these observations, we conducted an extensive immunogenetic analysis of multiple independent cohorts of HIV-1–, hepatitis C virus (HCV)–, and human T cell leukemia virus type 1 (HTLV-1)–infected individuals in conjunction with in vitro assays of T cell survival, analysis of ex vivo KIR expression, and mathematical modeling of host-virus dynamics. Our data suggest that functional engagement of inhibitory KIRs enhances the CD8+ T cell response against HIV-1, HCV, and HTLV-1 and is a significant determinant of clinical outcome in all three viral infections. Department of Medicine Imperial College London Faculty of Engineering São Paulo State University—UNESP Institute for Infection and Immunity St. George’s University of London International AIDS Vaccine Initiative Human Immunology Laboratory Clinical Research Department London School of Hygiene and Tropical Medicine Divi-sion of Infection and Immunity Cardiff University School of Medicine Nuffield Department of Medicine University of Oxford Oxford NIHR Biomedical Research Centre Immunology Division Department of Pathology University of Cambridge Cancer and Inflammation Program Leidos Biomedical Research Inc. Frederick National Laboratory for Cancer Research Johns Hopkins University Rho San Francisco Department of Public Health Faculty of Medicine University of Southampton Division of Cancer Epidemiology and Genetics National Cancer Institute Ragon Institute of MGH, MIT and Harvard Faculty of Engineering São Paulo State University—UNESP Wisconsin Turfgrass Association: 090323/Z/09/Z National Institutes of Health: 100326Z/12/Z Wellcome Trust: 103865Z/14/Z Institute for National Strategic Studies: 105609/Z/14/Z Leukemia and Lymphoma Research: 15012 Seventh Framework Programme: 317040 Horizon 2020: 695551 Medical Research Council Canada: G1001052 Medical Research Council Canada: J007439 National Institute on Drug Abuse: K24-AI118591 Medical Research Council Canada: MR/L018373/L Medical Research Council Canada: MR/M019829/1 Medical Research Council Canada: MR/P001602/1 National Institutes of Health: R01 DA13324 National Institute on Drug Abuse: R01-DA-12568 National Institute of Child Health and Human Development: R01-HD-41224 National Institute on Drug Abuse: U01-DA-036297

The authors that the number of activating and inhibitory KIR genes varies between individuals and plays a role in the regulation of immune mechanisms that determine HIV-1 control., A genome-wide screen for large structural variants showed that a copy number variant (CNV) in the region encoding killer cell immunoglobulin-like receptors (KIR) associates with HIV-1 control as measured by plasma viral load at set point in individuals of European ancestry. This CNV encompasses the KIR3DL1-KIR3DS1 locus, encoding receptors that interact with specific HLA-Bw4 molecules to regulate the activation of lymphocyte subsets including natural killer (NK) cells. We quantified the number of copies of KIR3DS1 and KIR3DL1 in a large HIV-1 positive cohort, and showed that an increase in KIR3DS1 count associates with a lower viral set point if its putative ligand is present (p = 0.00028), as does an increase in KIR3DL1 count in the presence of KIR3DS1 and appropriate ligands for both receptors (p = 0.0015). We further provide functional data that demonstrate that NK cells from individuals with multiple copies of KIR3DL1, in the presence of KIR3DS1 and the appropriate ligands, inhibit HIV-1 replication more robustly, and associated with a significant expansion in the frequency of KIR3DS1+, but not KIR3DL1+, NK cells in their peripheral blood. Our results suggest that the relative amounts of these activating and inhibitory KIR play a role in regulating the peripheral expansion of highly antiviral KIR3DS1+ NK cells, which may determine differences in HIV-1 control following infection., Author Summary There is marked intrinsic variation in the extent to which individuals are able to control HIV-1. We have identified a genetic copy number variable region (CNV) in humans that plays a significant role in the control of HIV-1. This CNV is located in the genomic region that encodes the killer cell immunoglobulin-like receptors (KIRs) and specifically affects the KIR3DS1 and KIR3DL1 genes, encoding two KIRs that interact with human leukocyte antigen B (HLA-B) ligands. KIRs are expressed on the surface of natural killer (NK) cells, which serve as important players in the innate immune response, and are involved in the recognition of infected and malignant cells through a loss or alteration in “self” ligands. We use both genetic association and functional evidence to show a strong interaction between KIR3DL1 and KIR3DS1, indicating that increasing gene counts for KIR3DL1 confer increasing levels of protection against HIV-1, but only in the presence of at least one copy of KIR3DS1. This effect was associated with a dramatic increase in the abundance of KIR3DS1+ NK cells in the peripheral blood, and strongly associated with a more robust capacity of peripheral NK cells to suppress HIV-1 replication in vitro. This work provides one of the few examples of an association between a relatively common CNV and a human complex trait.