Coordinación entre tutores y alumnos de Doctorado, Máster y Grado en un grupo de investigación

Memoria ID-0070. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2016-2017

Strong-LAMP: A LAMP Assay for Strongyloides spp. Detection in Stool and Urine Samples. Towards the Diagnosis of Human Strongyloidiasis Starting from a Rodent Model

[EN]Background: Strongyloides stercoralis, the chief causative agent of human strongyloidiasis, is a nematode globally distributed but mainly endemic in tropical and subtropical regions. Chronic infection is often clinically asymptomatic but it can result in severe hyperinfection syndrome or disseminated strongyloidiasis in immunocompromised patients. There is a great diversity of techniques used in diagnosing the disease, but definitive diagnosis is accomplished by parasitological examination of stool samples for morphological identification of parasite. Until now, no molecular method has been tested in urine samples as an alternative to stool samples for diagnosing strongyloidiasis. This study aimed to evaluate the use of a new molecular LAMP assay in a well-established Wistar rat experimental infection model using both stool and, for the first time, urine samples. The LAMP assay was also clinically evaluated in patients´ stool samples. Methodology/Principal Findings: Stool and urine samples were obtained daily during a 28-day period from rats infected subcutaneously with different infective third-stage larvae doses of S. venezuelensis. The dynamics of parasite infection was determined by daily counting the number of eggs per gram of feces from day 1 to 28 post-infection. A set of primers for LAMP assay based on a DNA partial sequence in the 18S rRNA gene from S. venezuelensis was designed. The set up LAMP assay (namely, Strong-LAMP) allowed the sensitive detection of S. venezuelensis DNA in both stool and urine samples obtained from each infection group of rats and was also effective in S. stercoralis DNA amplification in patients´ stool samples with previously confirmed strongyloidiasis by parasitological and real-time PCR tests. Conclusions/Significance: Our Strong-LAMP assay is an useful molecular tool in research of a strongyloidiasis experimental infection model in both stool and urine samples. After further validation, the Strong-LAMP could also be potentially applied for effective diagnosis of strongyloidiasis in a clinical setting. © 2016 Fernández-Soto et al

Evaluation of New Formulations of Antihelmintic Drugs for the Treatment of Schistosomiasis

La esquistosomosis es una enfermedad causada por parásitos trematodos del género Schistosoma. Afecta principalmente a áreas tropicales y subtropicales, siendo un principal problema de salud mundial por su alta incidencia en estas regiones. Una de las especies de mayor importancia, por su prevalencia y gravedad, es la causada por Schistosoma mansoni,responsable de la esquistosomosis intestinal. El tratamiento de elección esel praziquantel, con altas tasas de eficacia clínica. Sin embargo, el fármacono impide la reinfección y se ha observado fallos terapéuticos en zonasendémicas. Por ello, se hace necesaria la búsqueda de alternativas terapéuticas.El objetivo de este estudio es evaluar dos tipos de formulaciones denanopartículas de praziquantel (tipo A y tipo S) y un tratamiento alternativocomo la ivermectina mediante ensayos in vitro sobre adultos de S. mansoni.Los resultados demostraron que el tratamiento con nanopartículas presentauna eficacia similar o mayor que el empleo de praziquantel comercial. Sinembargo, el tratamiento con ivermectina no aportó evidencias de mayoreficacia. Trabajos futuros irán encaminados a evaluar estas formulacionesen otras fases del ciclo biológico, así como a realizar estudios in vivo enanimales de experimentación.Palabras clave: Schistosoma; esquistosomosis; praziquantel; nanopartículas;ivermectina.Fil: Castrillejo, Sergio A.. Universidad de Salamanca; EspañaFil: López Abán, Julio. Universidad de Salamanca; EspañaFil: Muro, Antonio. Universidad de Salamanca; EspañaFil: Salomon, Claudio Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Pastor Navarro, Marta. Universidad del País Vasco; España. Centro de Investigación Biomédica en Red; EspañaFil: Pedraz, José Luis. Universidad del País Vasco; España. Centro de Investigación Biomédica en Red; Españ

Combinatorial formulas for Kazhdan-Lusztig polynomials with respect to W-graph ideals

In \cite{y1} Yin generalized the definition of $W$-graph ideal $E_J$ in weighted Coxeter groups and introduced the weighted Kazhdan-Lusztig polynomials $\left \{ P_{x,y} \mid x,y\in E_J\right \}$, where $J$ is a subset of simple generators $S$. In this paper, we study the combinatorial formulas for those polynomials, which extend the results of Deodhar \cite{v3} and Tagawa \cite{h1}.Comment: 16 page

Transcriptome profiling of gene expression during immunisation trial against Fasciola hepatica : Identification of genes and pathways involved in conferring immunoprotection in a murine model

Background: Fasciolosis remains a significant food-borne trematode disease causing high morbidity around the world and affecting grazing animals and humans. A deeper understanding concerning the molecular mechanisms by which Fasciola hepatica infection occurs, as well as the molecular basis involved in acquiring protection is extremely important when designing and selecting new vaccine candidates. The present study provides a first report of microarray-based technology for describing changes in the splenic gene expression profile for mice immunised with a highly effective, protection-inducing, multi-epitope, subunit-based, chemically-synthesised vaccine candidate against F. hepatica. Methods: The mice were immunised with synthetic peptides containing B- and T-cell epitopes, which are derived from F. hepatica cathepsin B and amoebapore proteins, as novel vaccine candidates against F. hepatica formulated in an adjuvant adaptation vaccination system; they were experimentally challenged with F. hepatica metacercariae. Spleen RNA from mice immunised with the highest protection-inducing synthetic peptides was isolated, amplified and labelled using Affymetrix standardised protocols. Data was then background corrected, normalised and the expression signal was calculated. The Ingenuity Pathway Analysis tool was then used for analysing differentially expressed gene identifiers for annotating bio-functions and constructing and visualising molecular interaction networks. Results: Mice immunised with a combination of three peptides containing T-cell epitopes induced high protection against experimental challenge according to survival rates and hepatic damage scores. It also induced differential expression of 820 genes, 168 genes being up-regulated and 652 genes being down-regulated, p value <0.05, fold change ranging from -2.944 to 7.632. A functional study of these genes revealed changes in the pathways related to nitric oxide and reactive oxygen species production, Interleukin-12 signalling and production in macrophages and Interleukin-8 signalling with up-regulation of S100 calcium-binding protein A8, Matrix metallopeptidase 9 and CXC chemokine receptor 2 genes. Conclusion: The data obtained in the present study provided us with a more comprehensive overview concerning the possible molecular pathways implied in inducing protection against F. hepatica in a murine model, which could be useful for evaluating future vaccine candidates. © 2017 The Author(s)

Major Histocompatibility Complex Class II (DRB3) Genetic Diversity in Spanish Morucha and Colombian Normande Cattle Compared to Taurine and Zebu Populations

Bovine leukocyte antigens (BoLA) have been used as disease markers and immunological traits in cattle due to their primary role in pathogen recognition by the immune system. A higher MHC allele diversity in a population will allow presenting a broader peptide repertoire. However, loss of overall diversity due to domestication process can decrease a population’s peptide repertoire. Within the context of zebu and taurine cattle populations, BoLA-DRB3 genetic diversity in Spanish Morucha and Colombian Normande cattle was analyzed and an approach to estimate functional diversity was performed. Sequence-based typing was used for identifying 29, 23, 27, and 28 alleles in Spanish Morucha, Nariño-, Boyacá-, and Cundinamarca-Normande cattle, respectively. These breeds had remarkably low heterozygosity levels and the Hardy-Weinberg principle revealed significant heterozygote deficiency. FST and DA genetic distance showed that Colombian Normande populations had greater variability than other phenotypically homogeneous breeds, such as Holstein. It was also found that Spanish Morucha cattle were strongly differentiated from other cattle breeds. Spanish Morucha had greater divergence in the peptide-binding region regarding other cattle breeds. However, peptide-binding region covariation indicated that the potential peptide repertoire seemed equivalent among cattle breeds. Despite the genetic divergence observed, the extent of the potential peptide repertoire in the cattle populations studied appears to be similar and thus their pathogen recognition potential should be equivalent, suggesting that functional diversity might persist in the face of bottlenecks imposed by domestication and breeding. © Copyright © 2020 Bohórquez, Ordoñez, Suárez, Vicente, Vieira, López-Abán, Muro, Ordóñez and Patarroyo

Máster de Enfermedades Tropicales en las Redes Sociales: creación y uso de materiales audiovisuales, gestión de contenidos y difusión dentro del EEES.

Memoria ID-255. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2013-2014

Transformación de materiales para la impartición del Máster de Enfermedades Tropicales a la modalidad semipresencial

Memoria ID-0055. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2016-2017

LAMPhimerus: a novel LAMP assay for detecting Amphimerus sp. DNA in human stool samples

[EN]Amphimeriasis, a fish-borne zoonotic disease caused by the liver fluke Amphimerus spp., is a highly prevalent parasitic infection affecting an indigenous Amerindian group, the Chachi, living in rural and remote tropical areas along the RõÂo Cayapas and its tributaries in the north-western coastal rainforest of Ecuador. Very little is known about the clinical course and treatment of this disease, and the only method for diagnosing it is the parasitological microscopic detection of eggs from Amphimerus spp. in patients' stool samples. This method lacks sensitivity, and the morphology of the eggs may be confounded with other liver and intestinal flukes. New diagnostic tools that can improve the sensitivity and specificity for diagnosing Amphimerus spp. infection would be desirable. At present, LAMP technology shows all the characteristics required of a real-time assay with simple operation for potential use in the clinical diagnosis of infectious diseases, particularly in the field conditions in developing countries for most neglected tropical diseases. In this study, we developed and successfully evaluated a LAMP assay for detecting Amphimerus sp. in human stool samples. After further validation, our LAMP assay (LAMPhimerus) could be readily adapted for effective field diagnosis and disease surveillance in amphimeriasis- endemic areas

Peptides Derived of Kunitz-Type Serine Protease Inhibitor as Potential Vaccine Against Experimental Schistosomiasis

Schistosomiasis is a significant public health problem in sub-Saharan Africa, China, Southeast Asia, and regions of South and Central America affecting about 189 million people. Kunitz-type serine protease inhibitors have been identified as important players in the interaction of other flatworm parasites with their mammalian hosts. They are involved in host blood coagulation, fibrinolysis, inflammation, and ion channel blocking, all of them critical biological processes, which make them interesting targets to develop a vaccine. Here, we evaluate the protective efficacy of chemically synthesized T- and B-cell peptide epitopes derived from a kunitz protein from Schistosoma mansoni. Putative kunitz-type protease inhibitor proteins were identified in the S. mansoni genome, and their expression was analyzed by RNA-seq. Gene expression analyses showed that the kunitz protein Smp_147730 (Syn. Smp_311670) was dramatically and significantly up-regulated in schistosomula and adult worms when compared to the invading cercariae. T- and B-cell epitopes were predicted using bioinformatics tools, chemically synthesized, and formulated in the Adjuvant Adaptation (ADAD) vaccination system. BALB/c mice were vaccinated and challenged with S. mansoni cercariae. Kunitz peptides were highly protective in vaccinated BALB/c mice showing significant reductions in recovery of adult females (89–91%) and in the numbers of eggs trapped in the livers (77–81%) and guts (57–77%) of mice. Moreover, liver lesions were significantly reduced in vaccinated mice (64–65%) compared to infected control mice. The vaccination regime was well-tolerated with both peptides. We propose the use of these peptides, alone or in combination, as reliable candidates for vaccination against schistosomiasis. © Copyright © 2019 Hernández-Goenaga, López-Abán, Protasio, Vicente Santiago, del Olmo, Vanegas, Fernández-Soto, Patarroyo and Muro