Detección de gripe y de otros virus respiratorios durante un periodo pandémico y postpandémico de nueva variante de gripe

Los virus de la gripe se descubrieron y aislaron por primera vez en 1930 en el cerdo y posteriormente en 1933 en el ser humano. Se incluyen en la familia Orthomyxoviridae, que en la actualidad agrupa cinco géneros. Todos ellos son virus con ARN monocatenario, de tamaño medio, simetría helicoidal y provistos de una membrana de envoltura. La denominación de “myxovirus” se relaciona con su afinidad por la mucina, mucoproteína existente en el moco de diversas secreciones. La infección respiratoria aguda es la patología más frecuente a lo largo de la vida. En nuestro país, las enfermedades infecciosas son el motivo de más del 60% de las consultas en pediatría extrahospitalaria. De ellas, un 70% corresponden a una infección respiratoria, cuyo origen es vírico en más de la mitad de los casos. El trabajo consta de varios objetivos, entre ellos: Analizar mediante un estudio descriptivo las variables demográficas de la población sujeta a estudio dentro de la Comunidad autónoma de Castilla y León exponiendo la temporalidad mensual y estacional tanto de la Gripe pandémica, estacional y de los otros virus respiratorios: Se utilizaron 3895 muestras manejando 4 técnicas basadas en el diagnóstico molecular.Departamento de Anatomía Patológica, Microbiología, Medicina Preventiva y Salud Pública, Medicina Legal y Forens

Altered surface expression of insulin-degrading enzyme on monocytes and lymphocytes from COVID-19 patients both at diagnosis and after hospital discharge

Although the COVID-19 disease has developed into a worldwide pandemic, its pathophysiology remains to be fully understood. Insulin-degrading enzyme (IDE), a zinc-metalloprotease with a high affinity for insulin, has been found in the interactomes of multiple SARS-CoV-2 proteins. However, the relevance of IDE in the innate and adaptative immune responses elicited by circulating peripheral blood mononuclear cells is unknown. Here, we show that IDE is highly expressed on the surface of circulating monocytes, T-cells (both CD4+ and CD4−), and, to a lower extent, in B-cells from healthy controls. Notably, IDE’s surface expression was upregulated on monocytes from COVID-19 patients at diagnosis, and it was increased in more severe patients. However, IDE’s surface expression was downregulated (relative to healthy controls) 3 months after hospital discharge in all the studied immune subsets, with this effect being more pronounced in males than in females, and thus it was sex-dependent. Additionally, IDE levels in monocytes, CD4+ T-cells, and CD4− T-cells were inversely correlated with circulating insulin levels in COVID-19 patients (both at diagnosis and after hospital discharge). Of note, high glucose and insulin levels downregulated IDE surface expression by ~30% in the monocytes isolated from healthy donors, without affecting its expression in CD4+ T-cells and CD4− T-cells. In conclusion, our studies reveal the sex- and metabolism-dependent regulation of IDE in monocytes, suggesting that its regulation might be important for the recruitment of immune cells to the site of infection, as well as for glucometabolic control, in COVID-19 patients.This work was funded by the European Commission–NextGenerationEU (Regulation EU 2020/2094), through CSIC’s Global Health Platform (PTI Salud Global) and Junta de Castilla y León (Proyectos COVID 07.04.467B04.74011.0) to D.B. The project leading to these results had received funding from the “La Caixa” Foundation under agreement LCF/PR/PR18/51130007 to G.P. and grant PID2019-110496RB-C22 funded by MCIN/AEI/10.13039/501100011033 to G.P. This research was funded by the Programa Estratégico Instituto de Biología y Genética Molecular (IBGM), Junta de León and the European Social Fund (ORDER EDU/574/2018)

Gas6, una proteína dependiente de la vitamina k implicada en la respuesta a la infección por sars-cov-2

Trabajo presentado en el LXIII Congreso Nacional SEHH/ XXXVII Congreso Nacional SETH, celebrado en Pamplona (Navarra) del 14 al 16 de octubre de 2021

Growth Arrest-Specific Factor 6 (GAS6) Is Increased in COVID-19 Patients and Predicts Clinical Outcome

Producción CientíficaBackground: Growth arrest-specific factor 6 (GAS6) and the Tyro3, AXL, and MERTK (TAM) receptors counterbalance pro-inflammatory responses. AXL is a candidate receptor for SARS-CoV-2, particularly in the respiratory system, and the GAS6/AXL axis is targeted in current clinical trials against COVID-19. However, GAS6 and TAMs have not been evaluated in COVID-19 patients at emergency admission. Methods: Plasma GAS6, AXL, and MERTK were analyzed in 132 patients consecutively admitted to the emergency ward during the first peak of COVID-19. Results: GAS6 levels were higher in the SARS-CoV-2-positive patients, increasing progressively with the severity of the disease. Patients with initial GAS6 at the highest quartile had the worst outcome, with a 3-month survival of 65%, compared to a 90% survival for the rest. Soluble AXL exhibited higher plasma concentration in deceased patients, without significant differences in MERTK among SARS-CoV-2-positive groups. GAS6 mRNA was mainly expressed in alveolar cells and AXL in airway macrophages. Remarkably, THP-1 human macrophage differentiation neatly induces AXL, and its inhibition (bemcentinib) reduced cytokine production in human macrophages after LPS challenge. Conclusions: Plasma GAS6 and AXL levels reflect COVID-19 severity and could be early markers of disease prognosis, supporting a relevant role of the GAS6/AXL system in the immune response in COVID-19.Ministerio de Ciencia, Innovación y Universidades (project RTI2018-095672-B-I00)Instituto de Salud Carlos III - Fondo de Investigación Sanitaria (grants PI15/00531 and PI19/01410)Fundació La Marató TV3 (grants 20153030 and 20153031)Consejo Superior de Investigaciones Científicas (project CSIC-COV19-016/202020E155)Junta de Castilla y León (project 07.04.467B04.74011.0

Gender differences in the plasma concentration of the GAS6-TAM system in COVID-19 patients

Resumen del trabajo presentado en el 4th European Congress on Thrombosis and Haemostasis, celebrado en Gante (Bélgica), los días 14 y 15 de octubre de 2021Background: SARS-CoV-2 induces an immune response with potentially harmful effects for the patient due to an uncontrolled release of inflammatory factors, specially at the capillary wall. The vitamin K-dependent plasma protein GAS6 and the TAM (TYRO3, AXL, and MERTK) receptors play a relevant role among restorative mechanisms that counterbalance pro-inflammatory responses at the endothelial interface. Aims: To study the influence of gender on the effects of SARS-CoV-2 infection in the GAS6/TAM system, as reflected by plasma concentration at patient admittance at the emergency ward. Methods: The plasma content of GAS6, AXL, and MERTK was analyzed in a first group of 132 patients, 68 females and 64 males consecutively admitted to the emergency ward during the first peak of COVID-19. A confirmatory group was studied from the second wave of contagions. An analysis of gender differences in relation to the GAS6/TAM concentrations in plasma was performed on this population. Results: In accordance with recently published GAS6 levels, significantly higher in the SARS-CoV-2 positive than in negative patients, increased progressively with the severity of the disease in SARS-CoV-2 positive individual irrespective of the gender of the patient. In contrast, while soluble AXL exhibited higher plasma concentration in deceased patients and no significant differences were observed in MERTK concentration, differential gender analysis suggest differences in soluble TAM receptors. While a COVID-19 related increase in sAXL was observed in men, this was not the case in women. Oppositely, MERTK differences due to COVID-19 infection were only significant in women. Summary/Conclusion: GAS6-TAM system of ligands and receptors is implicated in the immune response to SARS-CoV-2 in patients from both genders. Plasma GAS6 levels paralleled COVID-19 severity being an early marker of disease prognosis in both sexes. In contrast, soluble TAM receptors presented a gender-specific behavior. Sex-related differences in sAXL and sMERTK expression in COVID-19 patients could affect therapy efficacy deserving further investigation

Host adaptive immunity deficiency in severe pandemic influenza

INTRODUCTION: Pandemic A/H1N1/2009 influenza causes severe lower respiratory complications in rare cases. The association between host immune responses and clinical outcome in severe cases is unknown. METHODS: We utilized gene expression, cytokine profiles and generation of antibody responses following hospitalization in 19 critically ill patients with primary pandemic A/H1N1/2009 influenza pneumonia for identifying host immune responses associated with clinical outcome. Ingenuity pathway analysis 8.5 (IPA) (Ingenuity Systems, Redwood City, CA) was used to select, annotate and visualize genes by function and pathway (gene ontology). IPA analysis identified those canonical pathways differentially expressed (P < 0.05) between comparison groups. Hierarchical clustering of those genes differentially expressed between groups by IPA analysis was performed using BRB-Array Tools v.3.8.1. RESULTS: The majority of patients were characterized by the presence of comorbidities and the absence of immunosuppressive conditions. pH1N1 specific antibody production was observed around day 9 from disease onset and defined an early period of innate immune response and a late period of adaptive immune response to the virus. The most severe patients (n = 12) showed persistence of viral secretion. Seven of the most severe patients died. During the late phase, the most severe patient group had impaired expression of a number of genes participating in adaptive immune responses when compared to less severe patients. These genes were involved in antigen presentation, B-cell development, T-helper cell differentiation, CD28, granzyme B signaling, apoptosis and protein ubiquitination. Patients with the poorest outcomes were characterized by proinflammatory hypercytokinemia, along with elevated levels of immunosuppressory cytokines (interleukin (IL)-10 and IL-1ra) in serum. CONCLUSIONS: Our findings suggest an impaired development of adaptive immunity in the most severe cases of pandemic influenza, leading to an unremitting cycle of viral replication and innate cytokine-chemokine release. Interruption of this deleterious cycle may improve disease outcome.The study was scientifically sponsored by the Spanish Society for Critical Care Medicine (SEMICYUC). Funding: MICCIN-FIS/JCYL-IECSCYL-SACYL (Spain): Programa de Investigación Comisionada en Gripe, GR09/0021-EMER07/050- PI081236-RD07/0067. CIHR-NIH-Sardinia Recherché-LKSF Canada support DJK.S

Th1 and Th17 hypercytokinemia as early host response signature in severe pandemic influenza

Abstract Introduction Human host immune response following infection with the new variant of A/H1N1 pandemic influenza virus (nvH1N1) is poorly understood. We utilize here systemic cytokine and antibody levels in evaluating differences in early immune response in both mild and severe patients infected with nvH1N1. Methods We profiled 29 cytokines and chemokines and evaluated the haemagglutination inhibition activity as quantitative and qualitative measurements of host immune responses in serum obtained during the first five days after symptoms onset, in two cohorts of nvH1N1 infected patients. Severe patients required hospitalization (n = 20), due to respiratory insufficiency (10 of them were admitted to the intensive care unit), while mild patients had exclusively flu-like symptoms (n = 15). A group of healthy donors was included as control (n = 15). Differences in levels of mediators between groups were assessed by using the non parametric U-Mann Whitney test. Association between variables was determined by calculating the Spearman correlation coefficient. Viral load was performed in serum by using real-time PCR targeting the neuraminidase gene. Results Increased levels of innate-immunity mediators (IP-10, MCP-1, MIP-1β), and the absence of anti-nvH1N1 antibodies, characterized the early response to nvH1N1 infection in both hospitalized and mild patients. High systemic levels of type-II interferon (IFN-γ) and also of a group of mediators involved in the development of T-helper 17 (IL-8, IL-9, IL-17, IL-6) and T-helper 1 (TNF-α, IL-15, IL-12p70) responses were exclusively found in hospitalized patients. IL-15, IL-12p70, IL-6 constituted a hallmark of critical illness in our study. A significant inverse association was found between IL-6, IL-8 and PaO2 in critical patients. Conclusions While infection with the nvH1N1 induces a typical innate response in both mild and severe patients, severe disease with respiratory involvement is characterized by early secretion of Th17 and Th1 cytokines usually associated with cell mediated immunity but also commonly linked to the pathogenesis of autoimmune/inflammatory diseases. The exact role of Th1 and Th17 mediators in the evolution of nvH1N1 mild and severe disease merits further investigation as to the detrimental or beneficial role these cytokines play in severe illness

COVID-19 vaccine failure

COVID-19 affects the population unequally with a higher impact on aged and immunosuppressed people. Hence, we assessed the effect of SARS-CoV-2 vaccination in immune compromised patients (older adults and oncohematologic patients), compared with healthy counterparts. While the acquired humoral and cellular memory did not predict subsequent infection 18 months after full immunization, spectral and computational cytometry revealed several subsets within the CD8+ T-cells, B-cells, NK cells, monocytes and CD45RA+ CCR7- Tγδ cells differentially expressed in further infected and non-infected individuals not just following immunization, but also prior to that. Of note, up to 7 subsets were found within the CD45RA+ CCR7- Tγδ population with some of them being expanded and other decreased in subsequently infected individuals. Moreover, some of these subsets also predicted COVID-induced hospitalization in oncohematologic patients. Therefore, we hereby have identified several cellular subsets that, even before vaccination, strongly related to COVID-19 vulnerability as opposed to the acquisition of cellular and/or humoral memory following vaccination with SARS-CoV2 mRNA vaccines.This study has been funded through Programa Estratégico Instituto de Biología y Genética Molecular (IBGM Junta de Castilla y León. Ref. CCVC8485), Junta de Castilla y León (Proyectos COVID 07.04.467B04.74011.0) and the European Commission – NextGenerationEU (Regulation EU 2020/2094), through CSIC's Global Health Platform (PTI Salud Global; SGL21-03-026 and SGL2021-03-038)N

Whole-Blood DNA Methylation Analysis Reveals Respiratory Environmental Traits Involved in COVID-19 Severity Following SARS-CoV-2 Infection

SARS-CoV-2 causes a severe inflammatory syndrome (COVID-19) leading, in many cases, to bilateral pneumonia, severe dyspnea and in ∼5% of these, death. DNA methylation is known to play an important role in the regulation of the immune processes behind COVID-19 progression, however it has not been studied in depth, yet. In this study, we aim to evaluate the implication of DNA methylation in COVID-19 progression by means of a genome-wide DNA methylation analysis combined with DNA genotyping. The results reveal the existence of epigenomic regulation of functional pathways associated with COVID-19 progression and mediated by genetic loci. We found an environmental trait-related signature that discriminates mild from severe cases, and regulates IL-6 expression via the transcription factor CEBP. The analyses suggest that an interaction between environmental contribution, genetics and epigenetics might be playing a role in triggering the cytokine storm described in the most severe cases.This work has been supported through Consejería de Transformación Económica, Industria, Conocimiento y Universidades of the regional government of Andalucía cofounded by the European Union through European Regional Development Fund (FEDER, CV20-10150), Consejo Superior de Investigaciones científicas (CSIC-COV19-016/202020E155) and Junta de Castilla y León (Proyectos COVID 07.04.467B04.74011.0 and IBGM excellence programme CLU-2029-02). G.B. is supported by the Instituto de Salud Carlos III (ISCIII, Spanish Health Ministry) through the Sara Borrell subprogram (CD18/00153).Peer reviewe