End-binding protein 1 regulates the metabolic fate of CD4+ T lymphoblasts and Jurkat T cells and the organization of the mitochondrial network.

The organization of the mitochondrial network is relevant for the metabolic fate of T cells and their ability to respond to TCR stimulation. This arrangement depends on cytoskeleton dynamics in response to TCR and CD28 activation, which allows the polarization of the mitochondria through their change in shape, and their movement along the microtubules towards the immune synapse. This work focus on the role of End-binding protein 1 (EB1), a protein that regulates tubulin polymerization and has been previously identified as a regulator of intracellular transport of CD3-enriched vesicles. EB1-interferred cells showed defective intracellular organization and metabolic strength in activated T cells, pointing to a relevant connection of the cytoskeleton and metabolism in response to TCR stimulation, which leads to increased AICD. By unifying the organization of the tubulin cytoskeleton and mitochondria during CD4+ T cell activation, this work highlights the importance of this connection for critical cell asymmetry together with metabolic functions such as glycolysis, mitochondria respiration, and cell viability.

Activation kinetics of regulatory molecules during immunological synapse in T cells.

T cell activation through TCR stimulation leads to the formation of the immunological synapse (IS), a specialized adhesion organized between T lymphocytes and antigen presenting cells (APCs) in which a dynamic interaction among signaling molecules, the cytoskeleton and intracellular organelles achieves proper antigen-mediated stimulation and effector function. The kinetics of molecular reactions at the IS is essential to determine the quality of the response to the antigen stimulation. Herein, we describe methods based on biochemistry, flow cytometry and imaging in live and fixed cells to study the activation state and dynamics of regulatory molecules at the IS in the Jurkat T cell line CH7C17 and primary human and mouse CD4+ T lymphocytes stimulated by antigen presented by Raji and HOM2 B cell lines and human and mouse dendritic cells.

Chaperonin CCT controls extracellular vesicle production and cell metabolism through kinesin dynamics.

Cell proteostasis includes gene transcription, protein translation, folding of de novo proteins, post-translational modifications, secretion, degradation and recycling. By profiling the proteome of extracellular vesicles (EVs) from T cells, we have found the chaperonin complex CCT, involved in the correct folding of particular proteins. By limiting CCT cell-content by siRNA, cells undergo altered lipid composition and metabolic rewiring towards a lipid-dependent metabolism, with increased activity of peroxisomes and mitochondria. This is due to dysregulation of the dynamics of interorganelle contacts between lipid droplets, mitochondria, peroxisomes and the endolysosomal system. This process accelerates the biogenesis of multivesicular bodies leading to higher EV production through the dynamic regulation of microtubule-based kinesin motors. These findings connect proteostasis with lipid metabolism through an unexpected role of CCT.

CD69-oxLDL ligand engagement induces Programmed Cell Death 1 (PD-1) expression in human CD4 + T lymphocytes.

The mechanisms that control the inflammatory-immune response play a key role in tissue remodelling in cardiovascular diseases. T cell activation receptor CD69 binds to oxidized low-density lipoprotein (oxLDL), inducing the expression of anti-inflammatory NR4A nuclear receptors and modulating inflammation in atherosclerosis. To understand the downstream T cell responses triggered by the CD69-oxLDL binding, we incubated CD69-expressing Jurkat T cells with oxLDL. RNA sequencing revealed a differential gene expression profile dependent on the presence of CD69 and the degree of LDL oxidation. CD69-oxLDL binding induced the expression of NR4A receptors (NR4A1 and NR4A3), but also of PD-1. These results were confirmed using oxLDL and a monoclonal antibody against CD69 in CD69-expressing Jurkat and primary CD4 + lymphocytes. CD69-mediated induction of PD-1 and NR4A3 was dependent on NFAT activation. Silencing NR4A3 slightly increased PD-1 levels, suggesting a potential regulation of PD-1 by this receptor. Moreover, expression of PD-1, CD69 and NR4A3 was increased in human arteries with chronic inflammation compared to healthy controls, with a strong correlation between PD-1 and CD69 mRNA expression (r = 0.655 P < 0.0001). Moreover, PD-1 was expressed in areas enriched in CD3 infiltrating T cells. Our results underscore a novel mechanism of PD-1 induction independent of TCR signalling that might contribute to the role of CD69 in the modulation of inflammation and vascular remodelling in cardiovascular diseases.

Post-translational modifications and stabilization of microtubules regulate transport of viral factors during infections.

Tubulin post-translational modifications (PTMs) constitute a source of diversity for microtubule (MT) functions, in addition to the different isotypes of α and ß-tubulin acting as building blocks of MTs. Also, MT-associated proteins (MAPs) confer different characteristics to MTs. The combination of all these factors regulates the stability of these structures that act as rails to transport organelles within the cell, facilitating the association of motor complexes. All these functions are involved in crucial cellular processes in most cell types, ranging from spindle formation in mitosis to the defense against incoming cellular threats during phagocytosis mediated by immune cells. The regulation of MT dynamics through tubulin PTMs has evolved to depend on many different factors that act in a complex orchestrated manner. These tightly regulated processes are particularly relevant during the induction of effective immune responses against pathogens. Viruses have proved not only to hijack MTs and MAPs in order to favor an efficient infection, but also to induce certain PTMs that improve their cellular spread and lead to secondary consequences of viral processes. In this review, we offer a perspective on relevant MT-related elements exploited by viruses.

A Differential Signature of Circulating miRNAs and Cytokines Between COVID-19 and Community-Acquired Pneumonia Uncovers Novel Physiopathological Mechanisms of COVID-19.

Coronavirus Disease 2019 (COVID-19) pneumonia is a life-threatening infectious disease, especially for elderly patients with multiple comorbidities. Despite enormous efforts to understand its underlying etiopathogenic mechanisms, most of them remain elusive. In this study, we compared differential plasma miRNAs and cytokines profiles between COVID-19 and other community-acquired pneumonias (CAP). A first screening and subsequent validation assays in an independent cohort of patients revealed a signature of 15 dysregulated miRNAs between COVID-19 and CAP patients. Additionally, multivariate analysis displayed a combination of 4 miRNAs (miR-106b-5p, miR-221-3p, miR-25-3p and miR-30a-5p) that significantly discriminated between both pathologies. Search for targets of these miRNAs, combined with plasma protein measurements, identified a differential cytokine signature between COVID-19 and CAP that included EGFR, CXCL12 and IL-10. Significant differences were also detected in plasma levels of CXCL12, IL-17, TIMP-2 and IL-21R between mild and severe COVID-19 patients. These findings provide new insights into the etiopathological mechanisms underlying COVID-19.

Treatment outcome in dually HIV-1 and HIV-2 coinfected patients living in Spain.

BACKGROUND: Whereas HIV-1 has spread globally, HIV-2 is mainly found in West Africa where dual HIV-1/HIV-2 coinfection is nowadays uncommon. Herein, we report the rate, main characteristics, and treatment outcomes of all dually infected patients living in Spain. METHODS: We identified retrospectively all persons coinfected with HIV-1 recorded at the Spanish HIV-2 registry. Dual infection had been confirmed using PCR in plasma and/or cells, and/or using discriminatory serological tests. RESULTS: From a total of 373 individuals with HIV-2 recorded at the Spanish registry, 34 (9.1%) were coinfected with HIV-1. Compared with HIV-2 monoinfected persons, dually infected patients were more often male (67.6%), presented with lower median CD4 cell counts (204 cells/µl), and had developed more frequently AIDS events (26.5%). Although 61.7% came from West Africa, 6 (17.6%) were native Spaniards. HIV-1 non-B subtypes were recognized in 75% of coinfected patients, being the most prevalent CRF02_AG. At baseline, 45% of dually infected patients had undetectable plasma HIV-2 RNA. After a median follow-up of 32 (13-48) months on antiretroviral therapy, dually infected patients achieved undetectable viremia in 85% for HIV-1, in 80% for HIV-2; and in 70% for both viruses. Median CD4 cell counts reached up to 418 cells/µl. CONCLUSION: Roughly 9% of individuals with HIV-2 infection living in Spain are coinfected with HIV-1. Overall, 70% of dually infected patients achieved viral suppression for both viruses under antiretroviral therapy. Given the relatively large population of West Africans living in Spain and the continuous migration flow from HIV-2 endemic areas, HIV-1/HIV-2 coinfection should always be excluded at first diagnosis in all HIV-seroreactive persons.

Benefits of hepatitis C cure with antivirals: why test and treat?

Chronic hepatitis C virus (HCV) infection is one of the major causes of death worldwide due to infectious agents. The advent of direct-acting antivirals has dramatically improved the chance of HCV elimination, even for patients with decompensated cirrhosis. Along with HCV cure, benefits are recognized in terms of regression of liver fibrosis and risk of hepatocellular carcinoma. Furthermore, beyond hepatic outcomes, several extrahepatic benefits may result from sustained HCV eradication, including improvements in the neurocognitive function and reduced cardiovascular disease risk. Finally, there is no doubt that the individual success of direct-acting antivirals is largely contributing to halt HCV transmission globally, in the absence of an effective HCV prophylactic vaccine.

Regression of liver fibrosis after curing chronic hepatitis C with oral antivirals in patients with and without HIV coinfection.

BACKGROUND: Treatment with direct-acting antivirals (DAA) eradicates hepatitis C virus (HCV) from most chronic carriers. Information on regression of liver fibrosis and the influence of HIV is scarce in cured patients. METHODS: All consecutive HCV-infected individuals treated with DAA at our institution were examined. Hepatic elastography was performed at baseline and at the time of SVR12. Liver fibrosis regression was defined as a shift from advanced fibrosis (Metavir F3-F4) to null-mild fibrosis (F0-F2) and/or a reduction greater than 30% kPa. AST to platelet ratio index (APRI) and fibrosis 4 (FIB-4) scores were calculated in parallel. RESULTS: A total of 260 patients were treated with DAA. All but 14 achieved SVR12 and represented the study population. HIV confection was present in 42%. At baseline, 57.2% had advanced liver fibrosis with a median of 11 kPa, FIB-4 of 2.4, and APRI of 0.95. At the time of SVR12, a median reduction of 2.1 kPa (P < 0.001) was recognized using elastography. A significant fibrosis regression was seen in 40%, being more frequent in patients with baseline advanced fibrosis than in those with null-mild fibrosis (52.3 vs. 22.5%; P < 0.001). Even so, 41.2% of patients with baseline F3-F4 kept within cirrhotic scores. In multivariable analysis, only baseline stiffness was significantly associated with the extent of liver fibrosis regression. CONCLUSION: HCV cure with DAA is associated with regression of liver fibrosis in most patients treated with DAA, as measured using elastography, FIB-4 and APRI. This benefit is more pronounced in patients with baseline advanced fibrosis and cirrhosis. The dynamics of liver fibrosis regression are not influenced by HIV coinfection.

Treatment and prevention of HIV infection with long-acting antiretrovirals.

INTRODUCTION: Current antiretroviral therapy allows to achieve and sustain maximal suppression of HIV replication in most treated patients. As result, the life expectancy of HIV-infected persons has improved dramatically and is nowadays similar to that of the HIV-negative population. However, oral antiretrovirals have to be taken daily and indefinitely to avoid resumption of HIV replication and selection of drug resistance. Unfortunately, drug adherence is often suboptimal and tends to decline over time. Areas covered: New drugs, formulations and delivery systems are being developed for extended-release of antiretrovirals. At this time, intramuscular cabotegravir and rilpivirine, dapivirine vaginal rings and tenofovir alafenamide subdermal implants are the products in more advanced stages of clinical development. Their pharmacokinetics/dynamics and safety/efficacy are reviewed. Expert commentary: In the absence of eradicative therapy for individuals with HIV infection and protective vaccines for persons at risk, long-term antiretroviral therapy is the best approach for preventing disease progression in patients and halting transmissions, either as result of 'treatment as prevention' for HIV carriers or 'pre-exposure prophylaxis' for uninfected individuals at risk. In all these scenarios, the advent of long-acting antiretrovirals will expand options for overcoming the challenge of suboptimal drug adherence and reduce the burden of HIV infection.

Baseline NS5A resistance associated substitutions may impair DAA response in real-world hepatitis C patients.

Oral DAA have demonstrated high efficacy as treatment of hepatitis C. However, the presence of resistance-associated substitutions (RAS) at baseline has occasionally been associated with impaired treatment response. Herein, we examined the impact of baseline RAS at the HCV NS5A gene region on treatment response in a real-life setting. All hepatitis C patients treated with DAA including NS5A inhibitors at our institution were retrospectively examined. The virus NS5A gene was analyzed using population sequencing at baseline and after 24 weeks of completing therapy in all patients that failed. All changes recorded at positions 28, 29, 30, 31, 32, 58, 62, 92, and 93 were considered. A total of 166 patients were analyzed. HCV genotypes were as follows: G1a (31.9%), G1b (48.2%), G3 (10.2%), and G4 (9.6%). Overall, 69 (41.6%) patients were coinfected with HIV and 46.7% had advanced liver fibrosis (Metavir F3-F4). Sixty (36.1%) patients had at least one RAS at baseline, including M28A/G/T (5), Q30X (12), L31I/F/M/V (6), T58P/S (25), Q/E62D (1), A92 K (7), and Y93C/H (15). Overall, 4.8% had two or more RAS, being more frequent in G4 (12.5%) followed by G1b (6.3%) and G1a (1.9%). Of 10 (6%) patients that failed DAA therapy, five had baseline NS5A RAS. No association was found for specific baseline RAS, although changes at position 30 were more frequent in failures than cures (22.2% vs 6.4%, P = 0.074). Moreover, the presence of two or more RAS at baseline was more frequent in failures (HR: 7.2; P = 0.029). Upon failure, six patients showed emerging RAS, including Q30C/H/R (3), L31M (1), and Y93C/H (2). Baseline NS5A RAS are frequently seen in DAA-naïve HCV patients. Two or more baseline NS5A RAS were found in nearly 5% and were significantly associated to DAA failure. Therefore, baseline NS5A testing should be considered when HCV treatment is planned with NS5A inhibitors.

Human T-lymphotropic virus type 1 infection and disease in Spain.

: Human T-lymphotropic virus type 1 (HTLV-1) infection is a neglected disease despite roughly 15 million people are chronically infected worldwide. Lifelong less than 10% of carriers develop life-threatening diseases, mostly a subacute myelopathy known as tropical spastic paraparesis (TSP) and a lymphoproliferative disorder named adult T-cell leukemia (ATL). HTLV-1 is efficiently transmitted perinatally (breastfeeding), sexually (more from men to women) and parenterally (transfusions, injection drug user (IDU), and transplants). To date there is neither prophylactic vaccine nor effective antiviral therapy. A total of 327 cases of HTLV-1 infection had been reported at the HTLV-1 Spanish registry until December 2016, of whom 34 had been diagnosed with TSP and 25 with ATL. Overall 62% were Latin American immigrants and 13% were persons of African origin. The incidence of HTLV-1 in Spain has remained stable for nearly a decade with 20-25 new cases yearly. Of the 21 newly diagnosed HTLV-1 cases during year 2016, one was a native Spaniard pregnant woman, and four presented with symptomatic disease, including three with ATL and one with TSP. Underdiagnosis of HTLV-1 in Spain must be high (iceberg model), which may account for the disproportionate high rate of symptomatic cases (almost 20%) and the late recognition of preventable HTLV-1 transmissions in special populations, such as newborns and transplant recipients. Our current estimate is of 10 000 persons living with HTLV-1 infection in Spain. Given the large flux of immigrants and visitors from HTLV-1 endemic regions to Spain, the expansion of HTLV-1 screening policies is warranted. At this time, it seems worth recommending HTLV testing to all donor/recipient organ transplants and pregnant women regardless place of birth. Although current leukoreduction procedures largely prevent HTLV-1 transmission by blood transfusions, HTLV testing of all first-time donors should be cost-effective contributing to unveil asymptomatic unaware HTLV-1 carriers.

Drug resistance mutations in HIV-2 patients failing raltegravir and influence on dolutegravir response.

Background: A broader extent of amino acid substitutions in the integrase of HIV-2 compared with HIV-1 might enable greater cross-resistance between raltegravir and dolutegravir in HIV-2 infection. Few studies have examined the virological response to dolutegravir in HIV-2 patients that failed raltegravir. Methods: All patients recorded in the HIV-2 Spanish cohort were examined. The integrase coding region was sequenced in viraemic patients. Changes associated with resistance to raltegravir and dolutegravir in HIV-1 were recorded. Results: From 319 HIV-2-infected patients recorded in the HIV-2 Spanish cohort, 53 integrase sequences from 30 individuals were obtained (20 raltegravir naive and 10 raltegravir experienced). Only one secondary mutation (E138A) was found in one of the 20 raltegravir-naive HIV-2 patients. For raltegravir-experienced individuals, the resistance mutation profile in 9 of 10 viraemic patients was as follows: N155H + A153G/S (four); Y143G + A153S (two); Q148R + G140A/S (two); and Y143C + Q91R (one). Of note, all patients with Y143G and N155H developed a rare non-polymorphic mutation at codon 153. Rescue therapy with dolutegravir was given to 5 of these 10 patients. After >6 months on dolutegravir therapy, three patients with baseline N155H experienced viral rebound. In two of them N155H was replaced by Q148K/R and in another by G118R. Conclusions: A wide repertoire of resistance mutations in the integrase gene occur in HIV-2-infected patients failing on raltegravir. Although dolutegravir may allow successful rescue in most HIV-2 raltegravir failures, we report and characterize three cases of dolutegravir resistance in HIV-2 patients, emerging variants Q148K and Q148R and a novel change G118R.

HTLV infection in HCV-antibody positive patients in Spain.

Since hepatitis C virus (HCV) and human T-lymphotropic virus (HTLV) share transmission routes, dual infection could be frequent. In Spain, HTLV underdiagnosis is highlighted by the high proportion of patients presenting either with tropical spastic paraparesis (TSP) or adult T-cell leukemia (ATL) at first diagnosis. We examined whether the renewed efforts for expanding HCV testing may provide a sentinel population that might selectively be targeted to unveil asymptomatic HTLV carriers. The presence of anti-HTLV antibodies was examined in 3,838 consecutive individuals with reactive HCV serology attended during the last three years at 13 hospitals distributed across the Spanish geography. Overall 71% were male and the median age was 41-years old. Foreigners represented 9% of the study population. A total of 50 individuals (1.3%) were seroreactive for HTLV, being 30 confirmed as HTLV-2 and two as HTLV-1 (0.12%). The remaining 18 had indeterminate Western blot patterns. Most individuals with HTLV-2 and HTLV indeterminate serology were HIV-positive, former injection drug users and native Spaniards. In contrast, the two HTLV-1 infections were found in men coming from Brazil and the Dominican Republic, respectively. In summary, the overall prevalence of HTLV infection in individuals living in Spain seropositive for HCV is 1.3%, more than 10-fold greater than in general outclinics in Spain. However, immigrants from HTLV-1 endemic regions and former injection drug users with HTLV-2 infection are by far the major contributory groups in HCV patients. Therefore, testing for HTLV in newly diagnosed HCV individuals would not contribute much to improve late HTLV diagnosis in Spain.

HIV type 2 epidemic in Spain: challenges and missing opportunities.

: HIV type 2 (HIV-2) is a neglected virus despite estimates of 1-2 million people infected worldwide. HIV-2 is less efficiently transmitted than HIV-1 by sex and from mother to child. Although AIDS may develop in HIV-2 carriers, it takes longer than in HIV-1-infected patients. In contrast with HIV-1 infection, there is no global pandemic caused by HIV-2, as the virus is largely confined to West Africa. In a less extent and due to socioeconomic ties and wars, HIV-2 is prevalent in Portugal and its former colonies in Brazil, India, Mozambique and Angola. Globally, HIV-2 infections are steadily declining over time. A total of 338 cases of HIV-2 infection had been reported at the Spanish HIV-2 registry until December 2016, of whom 63% were men. Overall 72% were sub-Saharan Africans, whereas 16% were native Spaniards. Dual HIV-1 and HIV-2 coinfection was found in 9% of patients. Heterosexual contact was the most likely route of HIV-2 acquisition in more than 90% of cases. Roughly one-third presented with CD4 cell counts less than 200 cells/µl and/or AIDS clinical events. Plasma HIV-2 RNA was undetectable at baseline in 40% of patients. To date, one-third of HIV-2 carriers have received antiretroviral therapy, using integrase inhibitors 32 individuals. New diagnoses of HIV-2 in Spain have remained stable since 2010 with an average of 15 cases yearly. Illegal immigration from Northwestern African borders accounts for over 75% of new HIV-2 diagnoses. Given the relatively large community of West Africans already living in Spain and the continuous flux of immigration from endemic regions, HIV-2 infection either alone or as coinfection with HIV-1 should be excluded once in all HIV-seroreactive persons, especially when showing atypical HIV serological profiles, immunovirological disconnect (CD4 cell count loss despite undetectable HIV-1 viremia) and/or high epidemiological risks (birth in or sex partners from endemic regions).

Impact of ITPA gene polymorphisms on the risk of ribavirin-induced haemolytic anaemia using interferon-free antivirals for chronic hepatitis C.

BACKGROUND: Single nucleotide polymorphisms (SNPs) at the ITPA gene are associated with haemolytic anaemia in chronic hepatitis C patients treated with pegylated interferon-ribavirin (RBV). Information in patients treated with interferon-free, direct-acting antivirals (DAA) is scarce. METHODS: Median haemoglobin (Hb) levels were compared at baseline and at week 4, when ribavirin concentration achieves steady state, in all consecutive chronic hepatitis C patients treated with oral DAA plus RBV at our clinic. RESULTS: Median Hb drop in 55 patients was greater in rs1127354-CC than -CA/AA (1.8 versus 0.7 g/dl; P=0.029), and in rs6051702-AA than -AC/CC carriers (2.2 versus 1.1 g/dl; P=0.016). Eleven (20%) patients experienced severe anaemia, defined as Hb drop >3 g/dl or to <10 g/dl. All of them were rs6051702-AA. CONCLUSIONS: Baseline testing of rs6051702 may identify the subset of patients at greatest risk for RBV-induced anaemia using interferon-free hepatitis C therapies.

Consideraciones para la construcción de un pacto fiscal

menciona que para la consolidación del modelo necesitan de la formulación y aplicación de una política económica con objetivos claros y definidos para el diseño de políticas sectoriales