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Purinergic receptors and NOD-like receptor protein 3 (NLRP3) inflammasome regulate inflammation and viral infection, but their effects on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remain poorly understood. Here, we report that the purinergic receptor P2X7 and NLRP3 inflammasome are cellular host factors required for SARS-CoV-2 infection. Lung autopsies from patients with severe coronavirus disease 2019 (COVID-19) reveal that NLRP3 expression is increased in host cellular targets of SARS-CoV-2 including alveolar macrophages, type II pneumocytes and syncytia arising from the fusion of infected macrophages, thus suggesting a potential role of NLRP3 and associated signaling pathways to both inflammation and viral replication. In vitro studies demonstrate that NLRP3-dependent inflammasome activation is detected upon macrophage abortive infection. More importantly, a weak activation of NLRP3 inflammasome is also detected during the early steps of SARS-CoV-2 infection of epithelial cells and promotes the viral replication in these cells. Interestingly, the purinergic receptor P2X7, which is known to control NLRP3 inflammasome activation, also favors the replication of D614G and alpha SARS-CoV-2 variants. Altogether, our results reveal an unexpected relationship between the purinergic receptor P2X7, the NLRP3 inflammasome and the permissiveness to SARS-CoV-2 infection that offers novel opportunities for COVID-19 treatment.
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COVID-19 , Inflamasomas , Humanos , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteínas NLR , Tratamiento Farmacológico de COVID-19 , SARS-CoV-2/metabolismo , Inflamación , Receptores PurinérgicosRESUMEN
BACKGROUND: In a restricted subset of HIV patients with suppressed viral load (i.e., pol-undetected HIV-RNA), the Aptima HIV-1 Quant Dx Assay (Aptima), a dual-target (pol and LTR) and dual-probe test for viral load (VL) monitoring, can detect HIV-RNA exclusively through amplification of the LTR region. OBJECTIVES: To analyze the virological characteristics of the HIV-RNA elements detected only through LTR amplification (LTR-e). STUDY DESIGN: LTR-e isolated from plasma and peripheral blood mononuclear cells (PBMC) were evaluated for their ability to trigger productive infections. Viral pellets morphology and ultrastructural characteristics of PBMC from LTR-e patients were examined by electron microscopy. Plasma LTR-e underwent Sanger sequencing. Exosomes were examined with Aptima for LTR-e content. RESULTS: In-vitro, LTR-e could not infect PBMC, induce cytopathic effects, or cause syncytia, even at high VL (e.g., >10,000 copies/mL). Under the electron microscope, plasma pellets and PBMC from patients with LTR-e showed atypical vesicles. Sanger sequencing of LTR-e yielded no results. Moreover, in plasma samples, LTR-e were associated with cell debris, never with exosomes. CONCLUSIONS: Differently from other dual-target but single-probe assays, Aptima unveils VL based only on LTR amplification in some HIV patients. Here, we show that LTR-e represent partial/incomplete/non-canonical transcripts unable to trigger productive infection or transmit HIV-1 infection. The recognition of VL based only on LTR-e in infected individuals is crucial as it allows to avoid inappropriate decisions in the clinical management of HIV patients, such as retesting of VL and switching of ART. Physicians and HIV-RNA dual-target assay manufacturers should consider the important implications of not recognizing this singular type of VL.
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Infecciones por VIH , Seropositividad para VIH , VIH-1 , Humanos , Infecciones por VIH/diagnóstico , VIH-1/genética , Leucocitos Mononucleares , ARN Viral/genética , Sensibilidad y Especificidad , Carga Viral/métodosRESUMEN
An essential function of the epidermis is to provide a physical barrier that prevents the loss of water. Essential mediators of this barrier function include ceramides, cholesterol, and very long chain fatty acids, and their alteration causes human pathologies, including psoriasis and atopic dermatitis. A frameshift mutation in the human ZNF750 gene, which encodes a zinc finger transcription factor, has been shown to cause a seborrhea-like dermatitis. Here, we show that genetic deletion of the mouse homolog ZFP750 results in loss of epidermal barrier function, which is associated with a substantial reduction of ceramides, nonpolar lipids. The alteration of epidermal lipid homeostasis is directly linked to the transcriptional activity of ZFP750. ZFP750 directly and/or indirectly regulates the expression of crucial enzymes primarily involved in the biosynthesis of ceramides. Overall, our study identifies the transcription factor ZFP750 as a master regulator epidermal homeostasis through lipid biosynthesis and thus contributing to our understanding of the pathogenesis of several human skin diseases.
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Metabolismo de los Lípidos , Piel , Animales , Humanos , Ratones , Ceramidas/metabolismo , Colesterol/metabolismo , Epidermis/metabolismo , Piel/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteínas Represoras/metabolismoRESUMEN
Cystic fibrosis (CF) is a rare autosomal recessive disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The most common mutation is F508del-CFTR (ΔF) which leads the encoded ion channel towards misfolding and premature degradation. The disease is characterized by chronic bronchopulmonary obstruction, inflammation and airways colonization by bacteria, which are the major cause of morbidity and mortality. The STING pathway is the main signaling route activated in the presence of both self and pathogen DNA, leading to Type I Interferon (IFN I) production and the innate immune response. In this study, we show for the first time the relationship existing in CF between resistant and recurrent opportunistic infections by Pseudomonas aeruginosa and the innate immunity impairment. We demonstrate through ex vivo and in vivo experiments that the pathway is inadequately activated in ΔF condition and the use of direct STING agonists, as 2',3'-cyclic GMP-AMP (2', 3' cGAMP), is able to restore the immune response against bacterial colonization. Indeed, upon treatment with the STING pathway agonists, we found a reduction of colony forming units (CFUs) consequent to IFN-ß enhanced production in Pseudomonas aeruginosa infected bone marrow derived macrophages and lung tissues from mice affected by Cystic Fibrosis. Importantly, we also verified that the impairment detected in the primary PBMCs obtained from ΔF patients can be corrected by 2', 3' cGAMP. Our work indicates that the cGAS/STING pathway integrity is crucial in the Cystic Fibrosis response against pathogens and that the restoration of the pathway by 2', 3' cGAMP could be exploited as a possible new target for the symptomatic treatment of the disease.
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Fibrosis Quística , Interferón Tipo I , Ratones , Animales , Fibrosis Quística/microbiología , Regulador de Conductancia de Transmembrana de Fibrosis Quística , Inmunidad Innata/genética , Interferón Tipo I/metabolismo , Macrófagos , Proteínas Serina-Treonina Quinasas/metabolismo , Factor 3 Regulador del Interferón/genética , Factor 3 Regulador del Interferón/metabolismoRESUMEN
Except for specific vaccines and monoclonal antibodies, effective prophylactic or post-exposure therapeutic treatments are currently limited for COVID-19. Propolis, a honeybee's product, has been suggested as a potential candidate for treatment of COVID-19 for its immunomodulatory properties and for its powerful activity against various types of viruses, including common coronaviruses. However, direct evidence regarding the antiviral activities of this product still remains poorly documented. VERO E6 and CALU3 cell lines were infected with SARS-CoV-2 and cultured in the presence of 12.5 or 25 µg/ml of a standardized Hydroalcoholic Extract acronym (sHEP) of Eurasian poplar type propolis and analyzed for viral RNA transcription, for cell damage by optical and electron microscopy, and for virus infectivity by viral titration at 2, 24, 48, and 72 h post-infection. The three main components of sHEP, caffeic acid phenethyl ester, galangin, and pinocembrin, were tested for the antiviral power, either alone or in combination. On both cell lines, sHEP showed significant effects mainly on CALU3 up to 48 h, i.e., some protection from cytopathic effects and consistent reduction of infected cell number, fewer viral particles inside cellular vesicles, reduction of viral titration in supernatants, dramatic drop of N gene negative sense RNA synthesis, and lower concentration of E gene RNA in cell extracts. Interestingly, pre-treatment of cells with sHEP before virus inoculation induced these same effects described previously and was not able to block virus entry. When used in combination, the three main constituents of sHEP showed antiviral activity at the same levels of sHEP. sHEP has a remarkable ability to hinder the replication of SARS-CoV-2, to limit new cycles of infection, and to protect host cells against the cytopathic effect, albeit with rather variable results. However, sHEP do not block the virus entry into the cells. The antiviral activity observed with the three main components of sHEP used in combination highlights that the mechanism underlying the antiviral activity of sHEP is probably the result of a synergistic effect. These data add further emphasis on the possible therapeutic role of this special honeybee's product as an adjuvant to official treatments of COVID-19 patients for its direct antiviral activity.
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SARS-CoV-2 infection can lead to a variety of clinical manifestations. The occurrence of tongue swelling has recently reported in severe cases of COVID-19, and angioedema has suggested as the causative mechanism. Several factors, such as genetic predisposing factor and angiotensin-converting enzyme inhibitors (ACEI) therapies, have proposed to induce angioedema, especially as concerns patients requiring ICU treatments. Nevertheless, the question is still debated and other causes not yet recognized should be considered. Here we present a case of macroglossia occurred in a patient deceased for COVID-19 disease, who had no family history of angioedema and did not receive ACEI as antihypertensive drug. Histological and immune-histochemical analysis revealed tongue muscle atrophy with infiltrating macrophages suggesting repair mechanisms, as seen in nerve injury recovery. These new pathological findings may open new fields of study on the pathogenesis of SARS-CoV-2.
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Angioedema , COVID-19 , Macroglosia , Angioedema/etiología , Inhibidores de la Enzima Convertidora de Angiotensina , COVID-19/complicaciones , Humanos , Macroglosia/etiologíaRESUMEN
Although lung fibrosis has a major impact in COVID-19 disease, its pathogenesis is incompletely understood. In particular, no direct evidence of pleura implication in COVID-19-related fibrotic damage has been reported so far. In this study, the expression of epithelial cytokeratins and Wilms tumor 1 (WT1), specific markers of mesothelial cells (MCs), was analyzed in COVID-19 and unrelated pleura autoptic samples. SARS-CoV-2 replication was analyzed by RT-PCR and confocal microscopy in MeT5A, a pleura MC line. SARS-CoV-2 receptors were analyzed by RT-PCR and western blot. Inflammatory cytokines from the supernatants of SARS-CoV-2-infected MeT5A cells were analysed by Luminex and ELLA assays. Immunohistochemistry of COVID-19 pleura patients highlighted disruption of pleura monolayer and fibrosis of the sub-mesothelial stroma, with the presence of MCs with fibroblastoid morphology in the sub-mesothelial stroma, but no evidence of direct infection in vivo. Interestingly, we found evidence of ACE2 expression in MCs from pleura of COVID-19 patients. In vitro analysis shown that MeT5A cells expressed ACE2, TMPRSS2, ADAM17 and NRP1, plasma membrane receptors implicated in SARS-CoV-2 cell entry and infectivity. Moreover, MeT5A cells sustained SARS-CoV-2 replication and productive infection. Infected MeT5A cells produced interferons, inflammatory cytokines and metalloproteases. Overall, our data highlight the potential role of pleura MCs as promoters of the fibrotic reaction and regulators of the immune response upon SARS-CoV-2 infection.
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COVID-19 presents with a wide range of clinical neurological manifestations. It has been recognized that SARS-CoV-2 infection affects both the central and peripheral nervous system, leading to smell and taste disturbances; acute ischemic and hemorrhagic cerebrovascular disease; encephalopathies and seizures; and causes most surviving patients to have long lasting neurological symptoms. Despite this, typical neuropathological features associated with the infection have still not been identified. Studies of post-mortem examinations of the cerebral cortex are obtained with difficulty due to laboratory safety concerns. In addition, they represent cases with different neurological symptoms, age or comorbidities, thus a larger number of brain autoptic data from multiple institutions would be crucial. Histopathological findings described here are aimed to increase the current knowledge on neuropathology of COVID-19 patients. We report post-mortem neuropathological findings of ten COVID-19 patients. A wide range of neuropathological lesions were seen. The cerebral cortex of all patients showed vascular changes, hyperemia of the meninges and perivascular inflammation in the cerebral parenchyma with hypoxic neuronal injury. Perivascular lymphocytic inflammation of predominantly CD8-positive T cells mixed with CD68-positive macrophages, targeting the disrupted vascular wall in the cerebral cortex, cerebellum and pons were seen. Our findings support recent reports highlighting a role of microvascular injury in COVID-19 neurological manifestations.
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COVID-19/patología , Corteza Cerebral/patología , Anciano , Anciano de 80 o más Años , Autopsia , Encéfalo/patología , Encéfalo/virología , Encefalopatías/patología , Encefalopatías/virología , Linfocitos T CD8-positivos/patología , Corteza Cerebral/virología , Femenino , Humanos , Inflamación , Macrófagos/patología , Masculino , Microvasos/patología , Microvasos/virología , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/patología , Enfermedades del Sistema Nervioso/virología , SARS-CoV-2/patogenicidadRESUMEN
There is still a lack of knowledge concerning the pathophysiology of death among COVID-19-deceased patients, and the question of whether a patient has died with or due to COVID-19 is still very much debated. In Italy, all deaths of patients who tested positive for SARS-CoV-2 are defined as COVID-19-related, without considering pre-existing diseases that may either contribute to or even cause death. Our study included nine subjects from two different nursing homes (Cases 1-4, Group A; Cases 5-9, Group B). The latter included patients who presumably died from CO poisoning due to a heating system malfunction. All subjects tested positive for COVID-19 both ante- and post-mortem and were examined using post-mortem computed tomography prior to autopsy. COVID-19 was determined to be a contributing cause in the deaths of four out of nine subjects (death due to COVID-19; i.e., pneumonia and sudden cardiac death). In the other five cases, for which CO poisoning was identified as the cause of death, the infection presumably had no role in exitus (death with COVID-19). In our attempt to classify our patients as dying with or due to COVID-19, we found the use of complete assessments (both histological analyses and computed tomography examination) fundamental.
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COVID-19 , Pandemias , Autopsia , Humanos , Casas de Salud , SARS-CoV-2RESUMEN
Liver injury in COVID-19 patients has progressively emerged, even in those without a history of liver disease, yet the mechanism of liver pathogenicity is still controversial. COVID-19 is frequently associated with increased serum ferritin levels, and hyperferritinemia was shown to correlate with illness severity. The liver is the major site for iron storage, and conditions of iron overload have been established to have a pathogenic role in development of liver diseases. We presented here six patients who developed severe COVID-19, with biochemical evidence of liver failure. Three cases were survived patients, who underwent liver biopsy; the other three were deceased patients, who were autopsied. None of the patients suffered underlying liver pathologies. Histopathological and ultrastructural analyses were performed. The most striking finding we demonstrated in all patients was iron accumulation into hepatocytes, associated with degenerative changes. Abundant ferritin particles were found enclosed in siderosomes, and large aggregates of hemosiderin were found, often in close contact with damaged mitochondria. Iron-caused oxidative stress may be responsible for mitochondria metabolic dysfunction. In agreement with this, association between mitochondria and lipid droplets was also found. Overall, our data suggest that hepatic iron overload could be the pathogenic trigger of liver injury associated to COVID-19.
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COVID-19/diagnóstico , Sobrecarga de Hierro/etiología , Fallo Hepático/etiología , Hígado/patología , Índice de Severidad de la Enfermedad , Adulto , Anciano , Antivirales , Biopsia , COVID-19/complicaciones , COVID-19/mortalidad , COVID-19/terapia , Femenino , Ferritinas/análisis , Hepatocitos/citología , Hepatocitos/patología , Humanos , Hierro/análisis , Hierro/metabolismo , Sobrecarga de Hierro/mortalidad , Sobrecarga de Hierro/patología , Sobrecarga de Hierro/terapia , Hígado/citología , Hígado/metabolismo , Fallo Hepático/mortalidad , Fallo Hepático/patología , Fallo Hepático/terapia , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Mitocondrias/patología , Respiración con Presión Positiva , SARS-CoV-2/aislamiento & purificaciónRESUMEN
Autophagy is a lysosomal-dependent degradative mechanism essential in maintaining cellular homeostasis, but it is also considered an ancient form of innate eukaryotic fighting against invading microorganisms. Mounting evidence has shown that HIV-1 is a critical target of autophagy that plays a role in HIV-1 replication and disease progression. In a special subset of HIV-1-infected patients that spontaneously and durably maintain extremely low viral replication, namely, long-term nonprogressors (LTNP), the resistance to HIV-1-induced pathogenesis is accompanied, in vivo, by a significant increase in the autophagic activity in peripheral blood mononuclear cells. Recently, a new player in the battle of autophagy against HIV-1 has been identified, namely, tripartite motif protein 5α (TRIM5α). In vitro data demonstrated that TRIM5α directly recognizes HIV-1 and targets it for autophagic destruction, thus protecting cells against HIV-1 infection. In this paper, we analyzed the involvement of this factor in the control of HIV-1 infection through autophagy, in vivo, in LTNP. The results obtained showed significantly higher levels of TRIM5α expression in cells from LTNP with respect to HIV-1-infected normal progressor patients. Interestingly, the colocalization of TRIM5α and HIV-1 proteins in autophagic vacuoles in LTNP cells suggested the participation of TRIM5α in the autophagy containment of HIV-1 in LTNP. Altogether, our results point to a protective role of TRIM5α in the successful control of the chronic viral infection in HIV-1-controllers through the autophagy mechanism. In our opinion, these findings could be relevant in fighting against HIV-1 disease, because autophagy inducers might be employed in combination with antiretroviral drugs.
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Infecciones por VIH/inmunología , Sobrevivientes de VIH a Largo Plazo , Proteínas de Motivos Tripartitos/inmunología , Ubiquitina-Proteína Ligasas/inmunología , Replicación Viral , Adulto , Anciano , Factores de Restricción Antivirales , Autofagia , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , VIH-1 , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
We have recently shown that type 2 transglutaminase (TG2) plays a key role in the host's inflammatory response during bacterial infections. In this study, we investigated whether the enzyme is involved in the regulation of the STING pathway, which is the main signaling activated in the presence of both self- and pathogen DNA in the cytoplasm, leading to type I IFN (IFN I) production. In this study, we demonstrated that TG2 negatively regulates STING signaling by impairing IRF3 phosphorylation in bone marrow-derived macrophages, isolated from wild-type and TG2 knockout mice. In the absence of TG2, we found an increase in the IFN-ß production and in the downstream JAK/STAT pathway activation. Interestingly, proteomic analysis revealed that TG2 interacts with TBK1, affecting its interactome composition. Indeed, TG2 ablation facilitates the TBK1-IRF3 interaction, thus indicating that the enzyme plays a negative regulatory effect on IRF3 recruitment in the STING/TBK1 complex. In keeping with these findings, we observed an increase in the IFNß production in bronchoalveolar lavage fluids from COVID-19-positive dead patients paralleled by a dramatic decrease of the TG2 expression in the lung pneumocytes. Taken together, these results suggest that TG2 plays a negative regulation on the IFN-ß production associated with the innate immunity response to the cytosolic presence of both self- and pathogen DNA.
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COVID-19/inmunología , Proteínas de Unión al GTP/inmunología , Inmunidad Innata , Factor 3 Regulador del Interferón/inmunología , Proteínas de la Membrana/inmunología , Proteínas Serina-Treonina Quinasas/inmunología , SARS-CoV-2/inmunología , Transducción de Señal/inmunología , Transglutaminasas/inmunología , Animales , COVID-19/genética , COVID-19/patología , Proteínas de Unión al GTP/genética , Humanos , Factor 3 Regulador del Interferón/genética , Interferón beta/genética , Interferón beta/inmunología , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Proteína Glutamina Gamma Glutamiltransferasa 2 , Proteínas Serina-Treonina Quinasas/genética , Transducción de Señal/genética , Transglutaminasas/genéticaRESUMEN
The early secretory pathway and autophagy are two essential and evolutionarily conserved endomembrane processes that are finely interlinked. Although growing evidence suggests that intracellular trafficking is important for autophagosome biogenesis, the molecular regulatory network involved is still not fully defined. In this study, we demonstrate a crucial effect of the COPII vesicle-related protein TFG (Trk-fused gene) on ULK1 puncta number and localization during autophagy induction. This, in turn, affects formation of the isolation membrane, as well as the correct dynamics of association between LC3B and early ATG proteins, leading to the proper formation of both omegasomes and autophagosomes. Consistently, fibroblasts derived from a hereditary spastic paraparesis (HSP) patient carrying mutated TFG (R106C) show defects in both autophagy and ULK1 puncta accumulation. In addition, we demonstrate that TFG activity in autophagy depends on its interaction with the ATG8 protein LC3C through a canonical LIR motif, thereby favouring LC3C-ULK1 binding. Altogether, our results uncover a link between TFG and autophagy and identify TFG as a molecular scaffold linking the early secretion pathway to autophagy.
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Autofagosomas/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Western Blotting , Técnica del Anticuerpo Fluorescente , Células HEK293 , Células HeLa , Humanos , Inmunoprecipitación , Péptidos y Proteínas de Señalización Intracelular/genética , Microscopía Electrónica de Transmisión , Proteínas Asociadas a Microtúbulos/genética , Proteínas/genética , Interferencia de ARNRESUMEN
The pathogenesis of SARS-CoV-2 remains to be completely understood, and detailed SARS-CoV-2 cellular cytopathic effects requires definition. We performed a comparative ultrastructural study of SARS-CoV-1 and SARS-CoV-2 infection in Vero E6 cells and in lungs from deceased COVID-19 patients. SARS-CoV-2 induces rapid death associated with profound ultrastructural changes in Vero cells. Type II pneumocytes in lung tissue showed prominent altered features with numerous vacuoles and swollen mitochondria with presence of abundant lipid droplets. The accumulation of lipids was the most striking finding we observed in SARS-CoV-2 infected cells, both in vitro and in the lungs of patients, suggesting that lipids can be involved in SARS-CoV-2 pathogenesis. Considering that in most cases, COVID-19 patients show alteration of blood cholesterol and lipoprotein homeostasis, our findings highlight a peculiar important topic that can suggest new approaches for pharmacological treatment to contrast the pathogenicity of SARS-CoV-2.
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COVID-19 , Gotas Lipídicas , Metabolismo de los Lípidos , Pulmón , SARS-CoV-2/metabolismo , Animales , COVID-19/metabolismo , COVID-19/patología , Chlorocebus aethiops , Efecto Citopatogénico Viral , Humanos , Gotas Lipídicas/ultraestructura , Gotas Lipídicas/virología , Pulmón/metabolismo , Pulmón/ultraestructura , Pulmón/virología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/ultraestructura , SARS-CoV-2/ultraestructura , Síndrome Respiratorio Agudo Grave/metabolismo , Síndrome Respiratorio Agudo Grave/patología , Células VeroRESUMEN
AIMS: Patients with severe respiratory syndrome caused by SARS-CoV-2 undergo cardiac complications due to hyper-inflammatory conditions. Although the presence of the virus has been detected in the myocardium of infected patients, and infection of induced pluripotent cell-derived cardiomyocytes has been demonstrated, the reported expression of Angiotensin-Converting Enzyme-2 (ACE2) in cardiac stromal cells suggests that SARS-CoV-2 may determine cardiac injury by sustaining productive infection and increasing inflammation. METHODS AND RESULTS: We analysed expression of ACE2 receptor in primary human cardiac stromal cells derived from cardiospheres, using proteomics and transcriptomics before exposing them to SARS-CoV-2 in vitro. Using conventional and high sensitivity PCR methods, we measured virus release in the cellular supernatants and monitored the intracellular viral bioprocessing. We performed high-resolution imaging to show the sites of intracellular viral production and demonstrated the presence of viral particles in the cells with electron microscopy. We finally used RT-qPCR assays to detect genes linked to innate immunity and fibrotic pathways coherently regulated in cells after exposure to the virus. CONCLUSIONS: Our findings indicate that cardiac stromal cells are susceptible to SARS-CoV-2 infection and produce variable viral yields depending on the extent of cellular ACE2 receptor expression. Interestingly, these cells also evolved towards hyper-inflammatory/pro-fibrotic phenotypes independently of ACE2 levels. Thus, SARS-CoV-2 infection of myocardial stromal cells could be involved in cardiac injury and explain the high number of complications observed in severe cases of COVID-19.
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Enzima Convertidora de Angiotensina 2/metabolismo , COVID-19/virología , Cardiopatías/virología , Miocardio/enzimología , Receptores Virales/metabolismo , SARS-CoV-2/patogenicidad , Células del Estroma/virología , Virión/patogenicidad , Anciano , Anciano de 80 o más Años , Enzima Convertidora de Angiotensina 2/genética , Animales , COVID-19/complicaciones , Chlorocebus aethiops , Femenino , Fibrosis , Cardiopatías/enzimología , Cardiopatías/patología , Interacciones Huésped-Patógeno , Humanos , Mediadores de Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Miocardio/ultraestructura , Fenotipo , Receptores Virales/genética , SARS-CoV-2/ultraestructura , Esferoides Celulares , Células del Estroma/enzimología , Células del Estroma/ultraestructura , Células Vero , Virión/ultraestructuraRESUMEN
It is not yet entirely clear what is the relevance of skin symptoms and what clinical implications are related to their appearance in COVID-19 patients. We describe two cases of COVID-19-associated pneumonia, which presented skin manifestations in advanced stage of illness, when nasopharyngeal swabs became negative for SARS-CoV-2. The first case presented erythematous, maculopapular lesions; the second developed petechial, vesicular and blood-encrusted lesions on the limbs. Histopathology documented perivascular lymphocytic infiltrates, with prevalent CD4+ T-cells in both patients. The research of SARS-CoV-2 in tissues with real time RT-PCR was negative. Basal keratinocytes displayed C4d deposits in one case, who developed laboratory signs indicative of a procoagulative condition at the same time as the skin rash. Skin manifestations during SARS-CoV-2 infection seem to be clinically relevant and further studies are necessary to assess if they are linked to systemic complications, lack of viral clearance or cascades of immune responses induced by the virus, even in patients affected by mild pneumonia.
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COVID-19 , Exantema , Prueba de COVID-19 , Eritema , Exantema/diagnóstico , Exantema/etiología , Humanos , SARS-CoV-2RESUMEN
BACKGROUND: A considerable number of SARS-CoV-2 infected individuals could be asymptomatic and don't need medical treatment. The clinical spectrum of SARS-CoV-2 infection ranges from asymptomatic cases, medium-intensity forms with mild to moderate symptoms, to severe ones with bilateral pneumonia and respiratory distress. In cases with severe presentation of SARS-CoV-2 infection, the induction of hypercoagulability is one of the pathophysiological mechanism that can contribute to death. CASE PRESENTATION: Here, we reported autoptic evidences of thrombotic pulmonary arterial fatal lesions in an asymptomatic COVID-19 patient, after swab negativization. Whole body complete post-mortem examination was performed, showing the presence of a large thrombus occluding the main pulmonary artery that was the cause of death. Histopathological analysis showed heterogeneous pattern of pathological changes in the lung tissue with numerous vascular thrombi, inflammatory cardiomyopathy and other histopathological modifications in kidneys, spleen and liver. CONCLUSIONS: This study provides evidences that also asymptomatic patients may be at risk to develop thrombotic complications. An appropriate diagnostic screening for thrombotic complications and the early treatment recommendations of antithrombotic drugs could represent an important topic even in asymptomatic individuals.
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The ongoing pandemic of coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), needs better treatment options both at antiviral and anti-inflammatory levels. It has been demonstrated that the aminothiol cysteamine, an already human applied drug, and its disulfide product of oxidation, cystamine, have anti-infective properties targeting viruses, bacteria, and parasites. To determine whether these compounds exert antiviral effects against SARS-CoV-2, we used different in vitro viral infected cell-based assays. Moreover, since cysteamine has also immune-modulatory activity, we investigated its ability to modulate SARS-CoV-2-specific immune response in vitro in blood samples from COVID-19 patients. We found that cysteamine and cystamine decreased SARS-CoV-2-induced cytopathic effects (CPE) in Vero E6 cells. Interestingly, the antiviral action was independent of the treatment time respect to SARS-CoV-2 infection. Moreover, cysteamine and cystamine significantly decreased viral production in Vero E6 and Calu-3 cells. Finally, cysteamine and cystamine have an anti-inflammatory effect, as they significantly decrease the SARS-CoV-2 specific IFN-γ production in vitro in blood samples from COVID-19 patients. Overall, our findings suggest that cysteamine and cystamine exert direct antiviral actions against SARS-CoV-2 and have in vitro immunomodulatory effects, thus providing a rational to test these compounds as a novel therapy for COVID-19.
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Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , Cisteamina/farmacología , Reposicionamiento de Medicamentos/métodos , Agentes Inmunomoduladores/farmacología , SARS-CoV-2/efectos de los fármacos , Anciano , Animales , COVID-19/virología , Línea Celular Tumoral , Chlorocebus aethiops , Cistamina/farmacología , Depletores de Cistina/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Viral/genética , ARN Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/fisiología , Células Vero , Replicación Viral/efectos de los fármacos , Replicación Viral/genéticaRESUMEN
COVID-19 can involve several organs and systems, often with indirect and poorly clarified mechanisms. Different presentations of myocardial injury have been reported, with variable degrees of severity, often impacting on the prognosis of COVID-19 patients. The pathogenic mechanisms underlying cardiac damage in SARS-CoV-2 infection are under active investigation. We report the clinical and autopsy findings of a fatal case of Takotsubo Syndrome occurring in an 83-year-old patient with COVID-19 pneumonia. The patient was admitted to Emergency Department with dyspnea, fever and diarrhea. A naso-pharyngeal swab test for SARS-CoV-2 was positive. In the following week his conditions worsened, requiring intubation and deep sedation. While in the ICU, the patient suddenly showed ST segment elevation. Left ventricular angiography showed decreased with hypercontractile ventricular bases and mid-apical ballooning, consistent with diagnosis of Takotsubo syndrome. Shortly after the patient was pulseless. After extensive resuscitation maneuvers, the patient was declared dead. Autopsy revealed a subepicardial hematoma, in absence of myocardial rupture. On histology, the myocardium showed diffuse edema, multiple foci of contraction band necrosis in both ventricles and occasional coagulative necrosis of single cardiac myocytes. Abundant macrophages CD68+ were detected in the myocardial interstitium. The finding of diffuse contraction band necrosis supports the pathogenic role of increased catecholamine levels; the presence of a significant interstitial inflammatory infiltrate, made up by macrophages, remains of uncertain significance.