38 research outputs found
In silico Design of an Epitope-Based Vaccine Ensemble for Chagas Disease
Trypanosoma cruzi infection causes Chagas disease, which affects 7 million people
worldwide. Two drugs are available to treat it: benznidazole and nifurtimox. Although
both are efficacious against the acute stage of the disease, this is usually asymptomatic
and goes undiagnosed and untreated. Diagnosis is achieved at the chronic stage, when
life-threatening heart and/or gut tissue disruptions occur in ∼30% of those chronically
infected. By then, the drugs’ efficacy is reduced, but not their associated high toxicity.
Given current deficiencies in diagnosis and treatment, a vaccine to prevent infection
and/or the development of symptoms would be a breakthrough in the management
of the disease. Current vaccine candidates are mostly based on the delivery of single
antigens or a few different antigens. Nevertheless, due to the high biological complexity
of the parasite, targeting as many antigens as possible would be desirable. In this
regard, an epitope-based vaccine design could be a well-suited approach. With this
aim, we have gone through publicly available databases to identify T. cruzi epitopes
from several antigens. By means of a computer-aided strategy, we have prioritized a
set of epitopes based on sequence conservation criteria, projected population coverage
of Latin American population, and biological features of their antigens of origin. Fruit of
this analysis, we provide a selection of CD8+ T cell, CD4+ T cell, and B cell epitopes that
have <70% identity to human or human microbiome protein sequences and represent
the basis toward the development of an epitope-based vaccine against T. cruzi
Diversity and antimicrobial potential in sea anemone and holothurian microbiomes
Marine invertebrates, as holobionts, contain symbiotic bacteria that coevolve and develop
antimicrobial substances. These symbiotic bacteria are an underexplored source of new
bioactive molecules to face the emerging antibiotic resistance in pathogens. Here, we
explored the antimicrobial activity of bacteria retrieved from the microbiota of two sea anemones
(Anemonia sulcata, Actinia equina) and two holothurians (Holothuria tubulosa,
Holothuria forskali). We tested the antimicrobial activity of the isolated bacteria against pathogens
with interest for human health, agriculture and aquaculture. We isolated 27 strains
with antibacterial activity and 12 of these isolates also showed antifungal activity. We taxonomically
identified these strains being Bacillus and Vibrio species the most representative
producers of antimicrobial substances. Microbiome species composition of the two sea
anemones was similar between them but differed substantially of seawater bacteria. In contrast,
microbiome species composition of the two holothurian species was different between
them and in comparison with the bacteria in holothurian feces and seawater. In all the holobiont
microbiomes Bacteroidetes was the predominant phylum. For each microbiome, we
determined diversity and the rank-abundance dominance using five fitted models (null, preemption,
log-Normal, Zipf and Zipf-Mandelbrot). The models with less evenness (i.e. Zipf
and Zipf-Mandelblot) showed the best fits in all the microbiomes. Finally, we tracked (using
the V4 hypervariable region of 16S rRNA gene) the relative abundance of these 27 isolates
with antibacterial activity in the total pool of sequences obtained for the microbiome of each
holobiont. Coincidences, although with extremely low frequencies, were detected only in the
microbiome of H. forskali. This fact suggests that these isolated bacteria belong to the long
tail of rare symbiotic bacteria. Therefore, more and more sophisticated culture techniques
are necessary to explore this apparently vast pool of rare symbiontic bacteria and to determine
their biotechnological potentiality.This work was supported by Campus de
Excelencia Internacional BIOTIC (CEI Biotic)
Universidad de Granada, http://biotic.ugr.es, Grant
PBS46. iMare Natural S.L. provided support in the
form of salaries for author PAA, but did not have
any additional role in the study design, data
collection and analysis, decision to publish, or
preparation of the manuscript. The specific role of
this author is articulated in the `author
contributions' section
Impact of cyberbullying in adolescents from 11 to 17 in Portugal
En este artículo se presenta una investigación nacional llevada a cabo en el contexto de Portugal y que ha tenido por objetivo analizar la incidencia del cyberbullying en adolescentes portugueses de entre 11 y 17 años. Para ello, se ha llevado a cabo un estudio cuantitativo empleando un cuestionario ad hoc como instrumento de recogida de información. La muestra ha estado compuesta por 739 estudiantes de 15 distritos del país. Los resultados señalan que un 19,5% de la muestra ha sido víctima de cyberbullying, el cual se ha manifestado principalmente mediante insultos y amenazas a través de Internet, teléfono e email, así como por la distribución de fotografías de contenido sexual sin consentimiento de las víctimas.In this article we present a national research carried out in the context of Portugal. The aim of this study was to analyze the incidence of cyberbullying in Portuguese adolescents between 11 and 17 years old. For this, a quantitative study has been carried out using an ad hoc questionnaire as an information collection tool. The sample was composed of 739 students from 15 districts of the country. The results indicate that 19.5% of the sample has been a victim of cyberbullying. The aggression has been manifested mainly through insults and threats through the Internet, telephone and email, as well as by the distribution of sexual photographs without the victims’ permission
Characterization of Conserved and Promiscuous Human Rhinovirus CD4 T Cell Epitopes
This research was supported by UCM research special funds to P.A.R. and by the CAM research agency through grant IND2020/BMD-17364 to P.A.R.Human rhinovirus (RV) is the most common cause of upper respiratory infections and exacerbations of asthma. In this work, we selected 14 peptides (6 from RV A and 8 from RV C) encompassing potential CD4 T cell epitopes. Peptides were selected for being highly conserved in RV A and C serotypes and predicted to bind to multiple human leukocyte antigen class II (HLA II) molecules. We found positive T cell recall responses by interferon gamma (IFNγ)-ELISPOT assays to eight peptides, validating seven of them (three from RV A and four from RV C) as CD4 T cell epitopes through intracellular cytokine staining assays. Additionally, we verified their promiscuous binding to multiple HLA II molecules by quantitative binding assays. According to their experimental HLA II binding profile, the combination of all these seven epitopes could be recognized by >95% of the world population. We actually determined IFNγ responses to a pool encompassing these CD4 T cell epitopes by intracellular cytokine staining, finding positive responses in 29 out of 30 donors. The CD4 T cell epitopes identified in this study could be key to monitor RV infections and to develop peptide-based vaccines against most RV A and C serotypes.Depto. de Inmunología, Oftalmología y ORLFac. de MedicinaTRUEComunidad de MadridUniversidad Complutense de Madridpu
Immune Tolerance in the Oral Mucosa
The oral mucosa is a site of intense immune activity, where a large variety of immune cells meet to provide a first line of defense against pathogenic organisms. Interestingly, the oral mucosa is exposed to a plethora of antigens from food and commensal bacteria that must be tolerated. The mechanisms that enable this tolerance are not yet fully defined. Many works have focused on active immune mechanisms involving dendritic and regulatory T cells. However, epithelial cells also make a major contribution to tolerance by influencing both innate and adaptive immunity. Therefore, the tolerogenic mechanisms concurring in the oral mucosa are intertwined. Here, we review them systematically, paying special attention to the role of oral epithelial cells
Naturally presented HLA class I–restricted epitopes from the neurotrophic factor S100-β are targets of the autoimmune response in type 1 diabetes
Type 1 diabetes (T1D) results from the destruction of pancreatic β-cells by the immune system, and CD8+ T lymphocytes are critical actors in this autoimmune response. Pancreatic islets are surrounded by a mesh of nervous cells, the peri-insular Schwann cells, which are also targeted by autoreactive T lymphocytes and express specific antigens, such as the neurotrophic factor S100-β. Previous work has shown increased proliferative responses to whole S100-β in both human T1D patients and the nonobese diabetic (NOD) mouse model. We describe for the first time naturally processed and presented epitopes (NPPEs) presented by class I human leukocyte antigen–A*02:01 (A2.1) molecules derived from S100-β. These NPPEs triggered IFN-γ responses more frequently in both newly diagnosed and long-term T1D patients compared with healthy donors. Furthermore, the same NPPEs are recognized during the autoimmune response leading to diabetes in A2.1-transgenic NOD mice as early as 4 wk of age. Interestingly, when these NPPEs are used to prevent diabetes in this animal model, an acceleration of the disease is observed together with an exacerbation in insulitis and an increase in S100-β–specific cytotoxicity in vaccinated animals. Whether these can be used in diabetes prevention needs to be carefully evaluated in animal models before use in future clinical assays.—Calviño-Sampedro, C., Gomez-Tourino, I., Cordero, O. J., Reche, P. A., Gómez-Perosanz, M., Sánchez-Trincado, J. L., Rodríguez, M. Á., Sueiro, A. M., Viñuela, J. E., Calviño, R. V. Naturally presented HLA class I–restricted epitopes from the neurotrophic factor S100-β are targets of the autoimmune response in type 1 diabetesThe authors thank Dr. Sefina Arif (King’s College London,
London, United Kingdom) for critically reviewing the manuscript.
This work was funded by the Ministerio de Economía y
Competitividad (Grant BIO2014-53091-C3-3-R to R.V.C.). During
this work, I.G.-T. was supported by a Maria Barbeito predoctoral
fellowship (Xunta de Galicia, La Coruña, Spain). During this
work, C.C.-S. was supported by a Deputación da Coruña grant
(2012–2013 and 2016–2017)S
Curvature-Based Environment Description for Robot Navigation Using Laser Range Sensors
This work proposes a new feature detection and description approach for mobile robot navigation using 2D laser range sensors. The whole process consists of two main modules: a sensor data segmentation module and a feature detection and characterization module. The segmentation module is divided in two consecutive stages: First, the segmentation stage divides the laser scan into clusters of consecutive range readings using a distance-based criterion. Then, the second stage estimates the curvature function associated to each cluster and uses it to split it into a set of straight-line and curve segments. The curvature is calculated using a triangle-area representation where, contrary to previous approaches, the triangle side lengths at each range reading are adapted to the local variations of the laser scan, removing noise without missing relevant points. This representation remains unchanged in translation or rotation, and it is also robust against noise. Thus, it is able to provide the same segmentation results although the scene will be perceived from different viewpoints. Therefore, segmentation results are used to characterize the environment using line and curve segments, real and virtual corners and edges. Real scan data collected from different environments by using different platforms are used in the experiments in order to evaluate the proposed environment description algorithm
Revisiting the epidemiology of bloodstream infections and healthcare-associated episodes: results from a multicentre prospective cohort in Spain (PRO-BAC Study)
PROBAC REIPI/GEIH-SEIMC/SAEI Group.The epidemiology of bloodstream infections (BSIs) is dynamic as it depends on microbiological, host and healthcare system factors. The aim of this study was to update the information regarding the epidemiology of BSIs in Spain considering the type of acquisition. An observational, prospective cohort study in 26 Spanish hospitals from October 2016 through March 2017 including all episodes of BSI in adults was performed. Bivariate analyses stratified by type of acquisition were performed. Multivariate analyses were performed by logistic regression. Overall, 6345 BSI episodes were included; 2510 (39.8%) were community-acquired (CA), 1661 (26.3%) were healthcare-associated (HCA) and 2056 (32.6%) hospital-acquired (HA). The 30-day mortality rates were 11.6%, 19.5% and 22.0%, respectively. The median age of patients was 71 years (interquartile range 60–81 years) and 3656 (58.3%; 95% confidence interval 57.1–59.6%) occurred in males. The proportions according to patient sex varied according to age strata. Escherichia coli (43.8%), Klebsiella spp. (8.9%), Staphylococcus aureus (8.9%) and coagulase-negative staphylococci (7.4%) were the most frequent pathogens. Multivariate analyses confirmed important differences between CA and HCA episodes, but also between HCA and HA episodes, in demographics, underlying conditions and aetiology. In conclusion, we have updated the epidemiological information regarding patients’ profiles, underlying conditions, frequency of acquisition types and aetiological agents of BSI in Spain. HCA is confirmed as a distinct type of acquisition.This work was financed by grants from Plan Nacional de I+D+i 2013–2016, Instituto de Salud Carlos III, Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Ciencia, Innovación y Universidades [PI16/01432] and the Spanish Network for Research in Infectious Diseases (REIPI) [RD16/0016/0001; RD16/0016/0008], co‐financed by the European Development Regional Fund ‘A way to achieve Europe’, Operative program Intelligent Growth 2014–2020
Risk Factors and Predictive Score for Bacteremic Biliary Tract Infections Due to Enterococcus faecalis and Enterococcus faecium: a Multicenter Cohort Study from the PROBAC Project
Biliary-tract bloodstream infections (BT-BSI) caused by Enterococcus faecalis and E. faecium are associated with inappropriate empirical treatment and worse outcomes compared to other etiologies. The objective of this study was to investigate the risk factors for enterococcal BT-BSI. Patients with BT-BSI from the PROBAC cohort, including consecutive patients with BSI in 26 Spanish hospitals between October 2016 and March 2017, were selected; episodes caused by E. faecalis or E. faecium and other causes were compared. Independent predictors for enterococci were identified by logistic regression, and a predictive score was developed. Eight hundred fifty episodes of BT-BSI were included; 73 (8.5%) were due to target Enterococcus spp. (48 [66%] were E. faecium and 25 [34%] E. faecalis). By multivariate analysis, the variables independently associated with Enterococcus spp. were (OR; 95% confidence interval): cholangiocarcinoma (4.48;1.32 to 15.25), hospital acquisition (3.58;2.11 to 6.07), use of carbapenems in the previous month (3.35;1.45 to 7.78), biliary prosthesis (2.19;1.24 to 3.90), and moderate or severe chronic kidney disease (1.55;1.07 to 2.26). The AUC of the model was 0.74 [95% CI0.67 to 0.80]. A score was developed, with 7, 6, 5, 4, and 2 points for these variables, respectively, with a negative predictive value of 95% for a score # 6. A model, including cholangiocarcinoma, biliary prosthesis, hospital acquisition, previous carbapenems, and chronic kidney disease showed moderate prediction ability for enterococcal BT-BSI. Although the score will need to be validated, this information may be useful for deciding empirical therapy in biliary tract infections when bacteremia is suspected. IMPORTANCE Biliary tract infections are frequent, and a significant cause of morbidity and mortality. Bacteremia is common in these infections, particularly in the elderly and patients with cancer. Inappropriate empirical treatment has been associated with increased risk of mortality in bacteremic cholangitis, and the probability of receiving inactive empirical treatment is higher in episodes caused by enterococci. This is because many of the antimicrobial agents recommended in guidelines for biliary tract infections lack activity against these organisms. To the best of our knowledge, this is the first study analyzing the predictive factors for enterococcal BT-BSI and deriving a predictive score.8 página
Metodología experimental aplicada a la Inmunología Molecular
El objetivo general del proyecto es aplicar un modelo pedagógico en el que participen los alumnos de manera activa y apliquen el método científico en base a los conocimientos que han adquirido, resolviendo y realizando un caso práctico en el laboratorio.
Integra una estrategia didáctica que va a fomentar la participación activa del alumnado provocando un aprendizaje significativo, ya que el alumno tiene que resolver mediante el razonamiento un caso práctico y luego integrarlo en el laboratorio con el uso de una técnica ampliamente utilizada en Inmunología, como es la citometría de flujo.Depto. de Arquitectura de Computadores y AutomáticaFac. de InformáticaFALSEInnovasubmitte