Search

Molecular epidemiology of circulating clinical isolates is crucial to improve prevention strategies. The Spanish Working Group on multidrug resistant tuberculosis (MDR-TB) is a network that monitors the MDR-TB isolates in Spain since 1998. The aim of this study was to present the study of the MDR-TB and extensively drug-resistant tuberculosis (XDR-TB) patterns in Spain using the different recommended genotyping methods over time by a national coordinated system. Based on the proposed genotyping methods in the European Union until 2018, the preservation of one method, MIRU-VNTR, applied to selected clustered strains permitted to maintain our study open for 20 years. The distribution of demographic, clinical and epidemiological characteristics of clustered and non-clustered cases of MDR/XDR tuberculosis with proportion differences as assessed by Pearson's chi-squared or Fisher's exact test was compared. The differences in the quantitative variables using the Student's-t test and the Mann-Whitney U test were evaluated. The results obtained showed a total of 48.4% of the cases grouped in 77 clusters. Younger age groups, having a known TB case contact (10.2% vs 4.7%) and XDR-TB (16.5% vs 1.8%) were significantly associated with clustering. The largest cluster corresponded to a Mycobacterium bovis strain mainly spread during the nineties. A total of 68.4% of the clusters detected were distributed among the different Spanish regions and six clusters involving 104 cases were grouped in 17 and 18 years. Comparison of the genotypes obtained with those European genotypes included in The European Surveillance System (TESSy) showed that 87 cases had become part of 20 European clusters. The continuity of MDR strain genotyping in time has offered a widespread picture of the situation that allows better management of this public health problem. It also shows the advantage of maintaining one genotyping method over time, which allowed the comparison between ancient, present and future samples. The molecular methods applied in this work were supported by the Carlos III Health Institute in the context of two consecutive Grants FIS15/0317 and 18/0336 and JC was awarded a scholarship by the Government of Aragon / European Social Fund, “Building Europe from Aragon”. Sí

The current virus pandemic has brought to the general attention the need of sharing resources for the development of antiviral strategies. In this framework, key players are collections of biological resources and derived products, which can provide different laboratories and Institutions with virological material of utmost importance. The European virus Archive - Global (EVA-GLOBAL; https://www.european-virus-archive.com/) is a non profit organisation including a global network with expertise in virology, consisting of 38 partner laboratories both based at EU member state and non-EU institutions (Romette et al., Antiviral Res 2018;158:127-134; Coutard et al., Biopreserv Biobank 2020;18:561-569). This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 871029. The aim of the project is to collect, amplify, characterize, standardize, authenticate, and distribute viruses and derived products. The main strengths of the network rely on the synergic collaboration between laboratories, the quality of the offer in terms of viruses and derived products, the availability of diagnostic material and protocols. New tools, techniques and concepts are continuously developed in the frame of all possible virological branches. An on-line catalogue, including products and services, is available to the scientific community. Starting in 2020, plant viruses have been included in EVAg catalogue, and synergic actions are being taken amongst the most important European plant virology institutions to establish a wide collection of viruses and isolates, as well as derived products and associated services. Quality standards are being envisaged and adapted to plant viruses, in order to maintain the high profile of the EVA-GLOBAL products. This will support the advancement of knowledge in plant virology. Moreover, the project will represent an essential contribution to the preservation of virus biodiversity.

Interferon gamma (IFN-gamma) release assays (IGRAs) are increasingly used to test for latent tuberculosis (TB) infection. Although highly specific, IGRAs have a relatively high false-negative rate in active TB patients. A more sensitive assay is needed. IFN-gamma-induced protein 10 (IP-10) is an alternative biomarker with a 100-foldhigher expression level than IFN-gamma, allowing for different analysis platforms, including molecular detection. The PCR technique is already an integrated tool in most TB laboratories and, thus, an obvious platform to turn to. In this case-control study, we investigated the diagnostic sensitivity and specificity of a molecular assay detecting IP-10 mRNA expression following antigen stimulation of a blood sample. We included 89 TB patients and 99 healthy controls. Blood was drawn in QuantiFeron-TB gold in-tube (QFT) assay tubes. Eight hours poststimulation, IP-10 mRNA expression was analyzed, and 20 h poststimulation, IP-10 and IFN-gamma protein plasma levels were analyzed using an in-house IP-10 enzyme-linked immunosorbent assay (ELISA) and the official QFT ELISA, respectively. The IP-10 mRNA assay provided high specificity (98%), sensitivity (80%), and area under the concentration-time curve (AUC) (0.97); however, the QFT assay provided a higher overall diagnostic potential, with specificity of 100%, sensitivity of 90%, and AUC of 0.99. The IP-10 protein assay performed on par with the QFT assay, with specificity of 98%, sensitivity of 87%, and AUC of 0.98. We have provided proof of high technical performance of a molecular assay detecting IP-10 mRNA expression. As a diagnostic tool, this assay would gain from further optimization, especially on the kinetics of IP-10 mRNA expression.

Globally, volcanic soils (Andosols or Andisols) cover 0.84% of the Earth’s terrestrial surface (Dahlgren et al., 2004). Around 60% of the area covered by volcanic soils is in tropical countries (Takahashi and Shoji, 2001). These soils possess very distinctive characteristics defined as andic properties (IUSS, 2015) that distinguish them from other soils in the world. These soils are of major relevance in areas with intense tectonic movements, such as The Circum-Pacific Ring of Fire (USGS, 2018) affecting areas as New Zealand, Japan, the Philippines, Aleutian Islands, Alaska, North America and South America among others (Figure 1)..., A nivel mundial, los suelos volcánicos (Andosoles o Andisoles) cubren el 0,84% de la superficie terrestre (Dahlgren et al., 2004). Aproximadamente, un 60% de la superficie cubierta por suelos volcánicos se encuentra en países tropicales (Takahashi y Shoji, 2001). Estos suelos poseen características muy distintivas definidas como propiedades ándicas (IUSS, 2015) que los distinguen de otros suelos del mundo. Estos suelos son de gran relevancia en áreas con intensos movimientos tectónicos, como el Cinturón de Fuego del Pacífico (USGS, 2018) que afecta a áreas como Nueva Zelanda, Japón, Filipinas, Islas Aleutianas, Alaska, América del Norte y América del Sur entre otras (Figura 1)...

Objective: Staphylococcus aureus is a particularly difficult pathogen to eradicate from the respiratory tract. Previous studies have highlighted the intracellular capacity of S.aureus in several phagocytic and non-phagocytic cells. The aim of this study was to define S.aureus interaction within a murine alveolar macrophage cell line.Methods: Cell line MH-S was infected with Newman strain. Molecular mechanisms involved in phagocytosis were explored. To assess whether S.aureus survives intracellularly quantitative (gentamicin protection assays and bacterial plating) and qualitative analysis (immunofluorescence microscopy) were performed. Bacterial colocalization with different markers of the endocytic pathway was examined to characterize its intracellular trafficking.Results: We found that S.aureus uptake requires host actin polymerization, microtubule assembly and activation of phosphatidylinositol 3-kinase signaling. Time course experiments showed that Newman strain was able to persist within macrophages at least until 28.5 h post infection. We observed that intracellular bacteria are located inside an acidic subcellular compartment, which co-localizes with the late endosome/lysosome markers Lamp-1, Rab7 and RILP. Colocalization counts with TMR-dextran might reflect a balance between bacterial killing and intracellular survival.Conclusions: This study indicates that S.aureus persists and replicates inside murine alveolar macrophages, representing a privileged niche that can potentially offer protection from antimicrobial activity and immunological host defense mechanisms.

Host susceptibility to respiratory tract infections (RTI) is dependent on both genetic and acquired risk factors. Repeated bacterial and viral RTI, such as pneumonia from encapsulated microorganisms, respiratory tract infections related to respiratory syncytial virus or influenza, and even the development of bronchiectasis and asthma, are often reported as the first symptom of primary immunodeficiencies. In the same way, neutropenia is a well-known risk factor for invasive aspergillosis, as well as lymphopenia for Pneumocystis, and mycobacterial infections. However, in the last decades a better knowledge of immune signaling networks and the introduction of next generation sequencing have increased the number and diversity of known inborn errors of immunity. On the other hand, the use of monoclonal antibodies targeting cytokines, such as tumor necrosis factor alpha has revealed new risk groups for infections, such as tuberculosis. The use of biological response modifiers has spread to almost all medical specialties, including inflammatory diseases and neoplasia, and are being used to target different signaling networks that may mirror some of the known immune deficiencies. From a clinical perspective, the individual contribution of genetics, and/or targeted treatments, to immune dysregulation is difficult to assess. The aim of this article is to review the known and newly described mechanisms of impaired immune signaling that predispose to RTI, including new insights into host genetics and the impact of biological response modifiers, and to summarize clinical recommendations regarding vaccines and prophylactic treatments in order to prevent infections.

Aim: Production of Matryoshka-type gastroresistant microparticles containing antibiotic-loaded poly lactic-co-glycolic acid (PLGA) nanoparticles (NP) against Mycobacterium tuberculosis. Materials & methods: The emulsification and evaporation methods were followed for the synthesis of PLGA-NPs and methacrylic acid-ethyl acrylate-based coatings to protect rifampicin from degradation under simulated gastric conditions. Results & conclusion: The inner antibiotic-loaded NPs here reported can be released under simulated intestinal conditions whereas their coating protects them from degradation under simulated gastric conditions. The encapsulation does not hinder the antituberculosis action of the encapsulated antibiotic rifampicin. A sustained antibiotic release could be obtained when using the drug-loaded encapsulated NPs. Compared with the administration of the free drug, a more effective elimination of M. tuberculosis was observed when applying the NPs against infected macrophages. The antibiotic-loaded PLGA-NPs were also able to cross an in vitro model of intestinal barrier. Matryoshka-type gastroresistant microparticles containing antibiotic-loaded poly lactic-co-glycolic acid nanoparticles against M. tuberculosis were produced to protect the antibiotic from degradation under simulated gastric conditions. The antibiotic-loaded poly lactic-co-glycolic acid nanoparticles were able to cross an in vitro model of intestinal barrier, being more effective in the elimination of M. tuberculosis when applied against infected macrophages compared with the use of the free drug. [GRAPHICS]