Tetraspanins, Another Piece in the HIV-1 Replication Puzzle

Despite the great research effort placed during the last decades in HIV-1 study, still some aspects of its replication cycle remain unknown. All this powerful research has succeeded in developing different drugs for AIDS treatment, but none of them can completely remove the virus from infected patients, who require life-long medication. The classical approach was focused on the study of virus particles as the main target, but increasing evidence highlights the importance of host cell proteins in HIV-1 cycle. In this context, tetraspanins have emerged as critical players in different steps of the viral infection cycle. Through their association with other molecules, including membrane receptors, cytoskeletal proteins, and signaling molecules, tetraspanins organize specialized membrane microdomains called tetraspanin-enriched microdomains (TEMs). Within these microdomains, several tetraspanins have been described to regulate HIV-1 entry, assembly, and transfer between cells. Interestingly, the importance of tetraspanins CD81 and CD63 in the early steps of viral replication has been recently pointed out. Indeed, CD81 can control the turnover of the HIV-1 restriction factor SAMHD1. This deoxynucleoside triphosphate triphosphohydrolase counteracts HIV-1 reverse transcription (RT) in resting cells via its dual function as dNTPase, catalyzing deoxynucleotide triphosphates into deoxynucleosides and inorganic triphosphate, and as exonuclease able to degrade single-stranded RNAs. SAMHD1 has also been related with the detection of viral nucleic acids, regulating the innate immune response and would promote viral latency. New evidences demonstrating the ability of CD81 to control SAMHD1 expression, and as a consequence, HIV-1 RT activity, highlight the importance of TEMs for viral replication. Here, we will briefly review how tetraspanins modulate HIV-1 infection, focusing on the latest findings that link TEMs to viral replication.This work was supported by grants BFU2014-55478-R; BIO2017-86500-R; Fundacion Ramon Areces and RYC-2012-11025 to MY-M; and was co-funded by Fondo Europeo de Desarrollo Regional (FEDER). HS was supported by a FPI-UAM Fellowship.S

CD9 controls integrin α5β1-mediated cell adhesion by modulating its association with the metalloproteinase ADAM17

Integrin α5β1 is a crucial adhesion molecule that mediates the adherence of many cell types to the extracellular matrix through recognition of its classic ligand fibronectin as well as to other cells through binding to an alternative counter-receptor, the metalloproteinase ADAM17/TACE. Interactions between integrin α5β1 and ADAM17 may take place both in trans (between molecules expressed on different cells) or in cis (between molecules expressed on the same cell) configurations. It has been recently reported that the cis association between α5β1 and ADAM17 keeps both molecules inactive, whereas their dissociation results in activation of their adhesive and metalloproteinase activities. Here we show that the tetraspanin CD9 negatively regulates integrin α5β1-mediated cell adhesion by enhancing the cis interaction of this integrin with ADAM17 on the cell surface. Additionally we show that, similarly to CD9, the monoclonal antibody 2A10 directed to the disintegrin domain of ADAM17 specifically inhibits integrin α5β1-mediated cell adhesion to its ligands fibronectin and ADAM17.This work has been supported by the grant SAF2016-77096-R from Ministerio Español de Economía y Competitividad (MINECO) awarded to CC, by a grant from Fundación Ramón Areces Ayudas a la Investigación en Ciencias de la Vida y de la Materia, 2014 awarded to MY-M, and by the Deutsche Forschungsgemeinschaft (SFB 877, A6, Z3 and SPP1710) to JG and I

CD9 Controls Integrin α5β1-Mediated Cell Adhesion by Modulating Its Association With the Metalloproteinase ADAM17

Integrin α5β1 is a crucial adhesion molecule that mediates the adherence of many cell types to the extracellular matrix through recognition of its classic ligand fibronectin as well as to other cells through binding to an alternative counter-receptor, the metalloproteinase ADAM17/TACE. Interactions between integrin α5β1 and ADAM17 may take place both in trans (between molecules expressed on different cells) or in cis (between molecules expressed on the same cell) configurations. It has been recently reported that the cis association between α5β1 and ADAM17 keeps both molecules inactive, whereas their dissociation results in activation of their adhesive and metalloproteinase activities. Here we show that the tetraspanin CD9 negatively regulates integrin α5β1-mediated cell adhesion by enhancing the cis interaction of this integrin with ADAM17 on the cell surface. Additionally we show that, similarly to CD9, the monoclonal antibody 2A10 directed to the disintegrin domain of ADAM17 specifically inhibits integrin α5β1-mediated cell adhesion to its ligands fibronectin and ADAM17

High sensitivity detection of extracellular vesicles immune-captured from urine by conventional flow cytometry

Extracellular vesicles (EVs) provide an invaluable tool to analyse physiological processes because they transport, in biological fluids, biomolecules secreted from diverse tissues of an individual. EV biomarker detection requires highly sensitive techniques able to identify individual molecules. However, the lack of widespread, affordable methodologies for high-throughput EV analyses means that studies on biomarkers have not been done in large patient cohorts. To develop tools for EV analysis in biological samples, we evaluated here the critical parameters to optimise an assay based on immunocapture of EVs followed by flow cytometry. We describe a straightforward method for EV detection using general EV markers like the tetraspanins CD9, CD63 and CD81, that allowed highly sensitive detection of urinary EVs without prior enrichment. In proof-of-concept experiments, an epithelial marker enriched in carcinoma cells, EpCAM, was identified in EVs from cell lines and directly in urine samples. However, whereas EVs isolated from 5–10 ml of urine were required for western blot detection of EpCAM, only 500 μl of urine were sufficient to visualise EpCAM expression by flow cytometry. This method has the potential to allow any laboratory with access to conventional flow cytometry to identify surface markers on EVs, even non-abundant proteins, using minimally processed biological samples.This work was supported by grants from the Spanish Ministry of Economy [SAF2015-69169-R (MINECO/FEDER) to MVG; REDIEX SAF2015-71231-REDT to both MVG and MYM; BFU2014-55478-R and BIO2017-86500-R to MYM], Madrid Regional Government [IMMUNOTHERCAN-CM (B2017/BMD-3733) to MVG and LMP] and grants from Fundación Ramón Areces to MYM

CD9 controls integrin α5β1-mediated cell adhesion by modulating its association with the metalloproteinase ADAM17

Integrin α5β1 is a crucial adhesion molecule that mediates the adherence of many cell types to the extracellular matrix through recognition of its classic ligand fibronectin as well as to other cells through binding to an alternative counter-receptor, the metalloproteinase ADAM17/TACE. Interactions between integrin α5β1 and ADAM17 may take place both in trans (between molecules expressed on different cells) or in cis (between molecules expressed on the same cell) configurations. It has been recently reported that the cis association between α5β1 and ADAM17 keeps both molecules inactive, whereas their dissociation results in activation of their adhesive and metalloproteinase activities. Here we show that the tetraspanin CD9 negatively regulates integrin α5β1-mediated cell adhesion by enhancing the cis interaction of this integrin with ADAM17 on the cell surface. Additionally we show that, similarly to CD9, the monoclonal antibody 2A10 directed to the disintegrin domain of ADAM17 specifically inhibits integrin α5β1-mediated cell adhesion to its ligands fibronectin and ADAM17.Ministerio Español de Economía y Competitividad (MINECO) awarded to CC; by a grant from Fundación Ramón Areces Ayudas a la Investigación en Ciencias de la Vida y de la Materia, 2014 awarded to MY-M; and by the Deutsche Forschungsgemeinschaft (SFB 877, A6, Z3 and SPP1710) to JG and IL.Peer Reviewe

Exosome beads array for multiplexed phenotyping in cancer

Exosomes are small extracellular vesicles (EV) released from all cells that differ from others EV in their cellular origin, abundance and biogenesis. These different types of extracellular vesicles are recognized as potential markers of human diseases, including cancer and, in recent years, there has been an important advance in the molecular characterization of exosomes from different types of cancer. In particular, due to their presence and stability in most body fluids and the similarity of their content with tumor cells, exosomes have great potential as non-invasive biomarkers for liquid biopsy. Nevertheless, the use of exosomes for diagnostic purposes has been limited by the lack of reproducible methods. Flow cytometry is a technique well adapted for a reproducible analysis of clinical samples. However, conventional flow cytometers do not allow the detection of particles <300 nm based on forward scattered light (FSC), and therefore do not allow the direct detection of exosomes. To overcome this limitation, the use of microsphere bead-based flow cytometry assays is proposed, which, together with an adequate selection of markers, would contribute to making liquid biopsy based on exosomes a reality.We gratefully acknowledge financial support from the Spanish Health Institute Carlos III (ISCIII) for the grants: FIS PI17/01930 and CB16/12/00400. Fundación Solórzano FS/38-2017. The Proteomics Unit belongs to ProteoRed, PRB3-ISCIII, supported by grant PT17/0019/0023, of the PE I + D + I 2017-2020, funded by ISCIII and FEDER

Self-rated health among people living with HIV in Spain in 2019: a cross-sectional study

Background: HIV infection has become a chronic disease and well-being of people living with HIV (PLHIV) is now of particular concern. The objectives of this paper were to describe self-rated health among PLHIV, on ART and on ART virally suppressed and to analyse its determinants. Methods: Data were obtained from a second-generation surveillance system based on a cross-sectional one-day survey in public hospitals. Epidemiological and clinical data were collected among HIV-infected inpatients and outpatients receiving HIV-related care the day of the survey in 86 hospitals in 2019. Self-rated health was measured using a question included in the National Health Survey: "In the last 12 months, how would you rate your health status?" an ordinal variable with five categories (very good, good, moderate, bad and very bad). For the analysis, these responses were dichotomized into two categories: 1 = very good/good and 0 = moderate, bad or very bad health status. Factors associated with very good/good self-rated health were estimated using logistic regression. Results: Of 800 PLHIV, 67.5% perceived their health as very good/good, 68.4% among PLHIV on ART and 71.7% of those virally suppressed. Having university education (adjusted odds ratio (aOR):2.1), being unemployed (aOR:0.3) or retired (aOR:0.2), ever being diagnosed of AIDS (aOR:0.6), comorbidities (aOR:0.3), less than 2 year since HIV diagnosis (aOR:0.3) and not receiving ART (aOR:0.3) were associated with good self-rated health. Moreover, among PLHIV on ART, viral load less than 200 copies (aOR:3.2) were related to better perceived health. Bad adherence was inversely associated with good self-rated health among PLHIV on ART (aOR:0.5) and of those virally suppressed (aOR:0.4). Conclusions: Nearly seven in 10 PLHIV in Spain considered their health status as very good/good, being higher among virally suppressed PLHIV. Both demographic and clinical determinants affect quality of life.Sin financiación3.670 JCR (2021) Q3, 60/94 Infectious Diseases1.042 SJR (2021) Q2, 89/301 Infectious DiseasesNo data IDR 2020UE

Self-rated health among people living with HIV in Spain in 2019: a cross-sectional study.

HIV infection has become a chronic disease and well-being of people living with HIV (PLHIV) is now of particular concern. The objectives of this paper were to describe self-rated health among PLHIV, on ART and on ART virally suppressed and to analyse its determinants. Data were obtained from a second-generation surveillance system based on a cross-sectional one-day survey in public hospitals. Epidemiological and clinical data were collected among HIV-infected inpatients and outpatients receiving HIV-related care the day of the survey in 86 hospitals in 2019. Self-rated health was measured using a question included in the National Health Survey: "In the last 12 months, how would you rate your health status?" an ordinal variable with five categories (very good, good, moderate, bad and very bad). For the analysis, these responses were dichotomized into two categories: 1 = very good/good and 0 = moderate, bad or very bad health status. Factors associated with very good/good self-rated health were estimated using logistic regression. Of 800 PLHIV, 67.5% perceived their health as very good/good, 68.4% among PLHIV on ART and 71.7% of those virally suppressed. Having university education (adjusted odds ratio (aOR):2.1), being unemployed (aOR:0.3) or retired (aOR:0.2), ever being diagnosed of AIDS (aOR:0.6), comorbidities (aOR:0.3), less than 2 year since HIV diagnosis (aOR:0.3) and not receiving ART (aOR:0.3) were associated with good self-rated health. Moreover, among PLHIV on ART, viral load less than 200 copies (aOR:3.2) were related to better perceived health. Bad adherence was inversely associated with good self-rated health among PLHIV on ART (aOR:0.5) and of those virally suppressed (aOR:0.4). Nearly seven in 10 PLHIV in Spain considered their health status as very good/good, being higher among virally suppressed PLHIV. Both demographic and clinical determinants affect quality of life.S

Executive summary of the SEPAR recommendations for the diagnosis and treatment of non-small cell lung cancer

The Thoracic Surgery and Thoracic Oncology groups of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) have backed the publication of a handbook on recommendations for the diagnosis and treatment of non-small cell lung cancer. Due to the high incidence and mortality of this disease, the best scientific evidence must be constantly updated and made available for consultation by healthcare professionals.To draw up these recommendations, we called on a wide-ranging group of experts from the different specialties, who have prepared a comprehensive review, divided into 4 main sections. The first addresses disease prevention and screening, including risk factors, the role of smoking cessation, and screening programs for early diagnosis. The second section analyzes clinical presentation, imaging studies, and surgical risk, including cardiological risk and the evaluation of respiratory function. The third section addresses cytohistological confirmation and staging studies, and scrutinizes the TNM and histological classifications, non-invasive and minimally invasive sampling methods, and surgical techniques for diagnosis and staging. The fourth and final section looks at different therapeutic aspects, such as the role of surgery, chemotherapy, radiation therapy, a multidisciplinary approach according to disease stage, and other specifically targeted treatments, concluding with recommendations on the follow-up of lung cancer patients and surgical and endoscopic palliative interventions in advanced stages. (C) 2016 SEPAR. Published by Elsevier Espana, S.L.U. All rights reserved