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1.
J Healthc Inform Res ; 8(2): 400-437, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38681761

RESUMEN

Emergency Medical Services (EMS) are crucial in delivering timely and effective medical care to patients in need. However, the complex and dynamic nature of operations poses challenges for decision-making processes at strategic, tactical, and operational levels. This paper proposes an action-driven strategy for EMS management, employing a multi-objective optimizer and a simulator to evaluate potential outcomes of decisions. The approach combines historical data with dynamic simulations and multi-objective optimization techniques to inform decision-makers and improve the overall performance of the system. The research focuses on the Friuli Venezia Giulia region in north-eastern Italy. The region encompasses various landscapes and demographic situations that challenge fairness and equity in service access. Similar challenges are faced in other regions with comparable characteristics. The Decision Support System developed in this work accurately models the real-world system and provides valuable feedback and suggestions to EMS professionals, enabling them to make informed decisions and enhance the efficiency and fairness of the system.

2.
Front Bioinform ; 3: 1286883, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38651055

RESUMEN

Antibodies are generated with great diversity in nature resulting in a set of molecules, each optimized to bind a specific target. Taking advantage of their diversity and specificity, antibodies make up for a large part of recently developed biologic drugs. For therapeutic use antibodies need to fulfill several criteria to be safe and efficient. Polyspecific antibodies can bind structurally unrelated molecules in addition to their main target, which can lead to side effects and decreased efficacy in a therapeutic setting, for example via reduction of effective drug levels. Therefore, we created a neural-network-based model to predict polyspecificity of antibodies using the heavy chain variable region sequence as input. We devised a strategy for enriching antibodies from an immunization campaign either for antigen-specific or polyspecific binding properties, followed by generation of a large sequencing data set for training and cross-validation of the model. We identified important physico-chemical features influencing polyspecificity by investigating the behaviour of this model. This work is a machine-learning-based approach to polyspecificity prediction and, besides increasing our understanding of polyspecificity, it might contribute to therapeutic antibody development.

3.
MAbs ; 12(1): 1846900, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33228444

RESUMEN

Transgenic animals incorporating human antibody genes are extremely attractive for drug development because they obviate subsequent antibody humanization procedures required for therapeutic translation. Transgenic platforms have previously been established using mice, but also more recently rats, chickens, and cows and are now in abundant use for drug development. However, rabbit-based antibody generation, with a strong track record for specificity and affinity, is able to include gene conversion mediated sequence diversification, thereby enhancing binder maturation and improving the variance/selection of output antibodies in a different way than in rodents. Since it additionally frequently permits good binder generation against antigens that are only weakly immunogenic in other organisms, it is a highly interesting species for therapeutic antibody generation. We report here on the generation, utilization, and analysis of the first transgenic rabbit strain for human antibody production. Through the knockout of endogenous IgM genes and the introduction of human immunoglobulin sequences, this rabbit strain has been engineered to generate a highly diverse human IgG antibody repertoire. We further incorporated human CD79a/b and Bcl2 (B-cell lymphoma 2) genes, which enhance B-cell receptor expression and B-cell survival. Following immunization against the angiogenic factor BMP9 (Bone Morphogenetic Proteins 9), we were able to isolate a set of exquisitely affine and specific neutralizing antibodies from these rabbits. Sequence analysis of these binders revealed that both somatic hypermutation and gene conversion are fully operational in this strain, without compromising the very high degree of humanness. This powerful new transgenic strategy will allow further expansion of the use of endogenous immune mechanisms in drug development.


Asunto(s)
Animales Modificados Genéticamente , Afinidad de Anticuerpos/inmunología , Especificidad de Anticuerpos/inmunología , Linfocitos B/inmunología , Inmunoglobulina G/inmunología , Animales , Humanos , Inmunoglobulina G/genética , Conejos
4.
Bioinformatics ; 35(10): 1774-1776, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-30321295

RESUMEN

MOTIVATION: Canonical forms of the antibody complementarity-determining regions (CDRs) were first described in 1987 and have been redefined on multiple occasions since. The canonical forms are often used to approximate the antibody binding site shape as they can be predicted from sequence. A rapid predictor would facilitate the annotation of CDR structures in the large amounts of repertoire data now becoming available from next generation sequencing experiments. RESULTS: SCALOP annotates CDR canonical forms for antibody sequences, supported by an auto-updating database to capture the latest cluster information. Its accuracy is comparable to that of a standard structural predictor but it is 800 times faster. The auto-updating nature of SCALOP ensures that it always attains the best possible coverage. AVAILABILITY AND IMPLEMENTATION: SCALOP is available as a web application and for download under a GPLv3 license at opig.stats.ox.ac.uk/webapps/scalop. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Programas Informáticos , Anticuerpos , Sitios de Unión de Anticuerpos , Regiones Determinantes de Complementariedad , Modelos Moleculares
5.
PLoS One ; 9(2): e86184, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24503933

RESUMEN

We have developed a robust platform to generate and functionally characterize rabbit-derived antibodies using B cells from peripheral blood. The rapid high throughput procedure generates a diverse set of antibodies, yet requires only few animals to be immunized without the need to sacrifice them. The workflow includes (i) the identification and isolation of single B cells from rabbit blood expressing IgG antibodies, (ii) an elaborate short term B-cell cultivation to produce sufficient monoclonal antigen specific IgG for comprehensive phenotype screens, (iii) the isolation of VH and VL coding regions via PCR from B-cell clones producing antigen specific and functional antibodies followed by the sequence determination, and (iv) the recombinant expression and purification of IgG antibodies. The fully integrated and to a large degree automated platform (demonstrated in this paper using IL1RL1 immunized rabbits) yielded clonal and very diverse IL1RL1-specific and functional IL1RL1-inhibiting rabbit antibodies. These functional IgGs from individual animals were obtained at a short time range after immunization and could be identified already during primary screening, thus substantially lowering the workload for the subsequent B-cell PCR workflow. Early availability of sequence information permits one to select early-on function- and sequence-diverse antibodies for further characterization. In summary, this powerful technology platform has proven to be an efficient and robust method for the rapid generation of antigen specific and functional monoclonal rabbit antibodies without sacrificing the immunized animal.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/sangre , Linfocitos B/metabolismo , Ensayos Analíticos de Alto Rendimiento/métodos , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/sangre , Secuencia de Aminoácidos , Animales , Especificidad de Anticuerpos/inmunología , Separación Celular , Células Cultivadas , Células Clonales , Epítopos/inmunología , Células HEK293 , Humanos , Inmunización , Cadenas Pesadas de Inmunoglobulina/inmunología , Cadenas Ligeras de Inmunoglobulina/inmunología , Región Variable de Inmunoglobulina/inmunología , Proteína 1 Similar al Receptor de Interleucina-1 , Interleucina-33 , Interleucinas/metabolismo , Unión Proteica , Conejos , Receptores de Superficie Celular/metabolismo
6.
PLoS One ; 6(6): e21045, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21695153

RESUMEN

Rabbits are widely used in biomedical research, yet techniques for their precise genetic modification are lacking. We demonstrate that zinc finger nucleases (ZFNs) introduced into fertilized oocytes can inactivate a chosen gene by mutagenesis and also mediate precise homologous recombination with a DNA gene-targeting vector to achieve the first gene knockout and targeted sequence replacement in rabbits. Two ZFN pairs were designed that target the rabbit immunoglobulin M (IgM) locus within exons 1 and 2. ZFN mRNAs were microinjected into pronuclear stage fertilized oocytes. Founder animals carrying distinct mutated IgM alleles were identified and bred to produce offspring. Functional knockout of the immunoglobulin heavy chain locus was confirmed by serum IgM and IgG deficiency and lack of IgM(+) and IgG(+) B lymphocytes. We then tested whether ZFN expression would enable efficient targeted sequence replacement in rabbit oocytes. ZFN mRNA was co-injected with a linear DNA vector designed to replace exon 1 of the IgM locus with ∼1.9 kb of novel sequence. Double strand break induced targeted replacement occurred in up to 17% of embryos and in 18% of fetuses analyzed. Two major goals have been achieved. First, inactivation of the endogenous IgM locus, which is an essential step for the production of therapeutic human polyclonal antibodies in the rabbit. Second, establishing efficient targeted gene manipulation and homologous recombination in a refractory animal species. ZFN mediated genetic engineering in the rabbit and other mammals opens new avenues of experimentation in immunology and many other research fields.


Asunto(s)
Desoxirribonucleasas/química , Desoxirribonucleasas/genética , Inmunoglobulina M/genética , Ingeniería de Proteínas/métodos , Dedos de Zinc , Alelos , Animales , Secuencia de Bases , Exones/genética , Femenino , Técnicas de Inactivación de Genes , Sitios Genéticos/genética , Humanos , Inmunoglobulina G/genética , Inmunoglobulina M/deficiencia , Masculino , Microinyecciones , Datos de Secuencia Molecular , Mutación/genética , Oocitos/metabolismo , ARN Mensajero/genética , Conejos , Reproducibilidad de los Resultados
7.
Gene ; 330: 49-59, 2004 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-15087123

RESUMEN

A bacterial artificial chromosome (BAC) library was created using partially digested rabbit chromosomal DNA. Four BAC clones spanning about 0.5 Mb of the rabbit immunoglobulin (Ig) heavy chain locus were isolated and sequenced. Three of the BAC clones were partially overlapping. Thirty-four V elements, 11 D elements, DQ52, six J elements and the coding regions of Cmicro, Cgamma, C and four Calpha genes were identified and characterized. Additionally, the sequence of a fosmid clone spanning Calpha13 and 30 kb 3'enhancer region was determined. The organization of the locus and the potential function of newly identified functional and structural elements are discussed.


Asunto(s)
Cadenas Pesadas de Inmunoglobulina/genética , Conejos/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cromosomas Artificiales Bacterianos/genética , ADN/química , ADN/genética , Biblioteca Genómica , Mutación de Línea Germinal , Inmunoglobulina E/genética , Masculino , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
8.
Biochemistry ; 41(23): 7334-43, 2002 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-12044165

RESUMEN

The chlorophyll a/b-xanthophyll-protein CP26 complex belongs to the Lhc protein family. It binds nine chlorophylls and two xanthophylls per 26.6 kDa polypeptide. Determination of the characteristics of each binding site is needed for the understanding of functional organization of individual proteins belonging to the photosystem II supramolecular complex. The biochemical and spectroscopic features of native CP26 are presented here together with identification of pigment binding and energy transitions in different sites. The analysis has been performed via a new approach using recombinant CP26 complexes in which the chromophore content has been experimentally modified. Data were interpreted on the basis of homology with CP29 and LHCII complexes, for which detailed knowledge is available from mutation analysis. We propose that one additional Chl b is present in CP26 as compared to CP29 and that it is located in site B2. We also found that in CP26 three chlorophyll binding sites are selective for Chl a, one of them being essential for the folding of the pigment-protein complex. Two xanthophyll binding sites were identified, one of which (L1) is essential for protein folding and specifically binds lutein. The second site (L2) has lower selectivity and can bind any of the xanthophyll species present in thylakoids.


Asunto(s)
Complejos de Proteína Captadores de Luz , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Complejo de Proteína del Fotosistema II , Proteínas de Plantas/química , Sitios de Unión , Clorofila/química , Clorofila/metabolismo , Clorofila A , Proteínas de Unión a Clorofila , Dicroismo Circular , Proteínas del Complejo del Centro de Reacción Fotosintética/aislamiento & purificación , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/metabolismo , Desnaturalización Proteica , Pliegue de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Espectrometría de Fluorescencia , Espectrofotometría , Tilacoides/química , Xantófilas/química , Xantófilas/metabolismo , Zea mays/química
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