Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35.265
Filtrar
1.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502134

RESUMO

The current spreading coronavirus SARS-CoV-2 is highly infectious and pathogenic. In this study, we screened the gene expression of three host receptors (ACE2, DC-SIGN and L-SIGN) of SARS coronaviruses and dendritic cells (DCs) status in bulk and single cell transcriptomic datasets of upper airway, lung or blood of COVID-19 patients and healthy controls. In COVID-19 patients, DC-SIGN gene expression was interestingly decreased in lung DCs but increased in blood DCs. Within DCs, conventional DCs (cDCs) were depleted while plasmacytoid DCs (pDCs) were augmented in the lungs of mild COVID-19. In severe cases, we identified augmented types of immature DCs (CD22+ or ANXA1+ DCs) with MHCII downregulation. In this study, our observation indicates that DCs in severe cases stimulate innate immune responses but fail to specifically present SARS-CoV-2. It provides insights into the profound modulation of DC function in severe COVID-19.


Assuntos
COVID-19/imunologia , Moléculas de Adesão Celular/genética , Células Dendríticas/imunologia , Regulação da Expressão Gênica/imunologia , Lectinas Tipo C/genética , Receptores de Superfície Celular/genética , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/diagnóstico , COVID-19/patologia , COVID-19/virologia , Moléculas de Adesão Celular/metabolismo , Conjuntos de Dados como Assunto , Células Dendríticas/metabolismo , Estudo de Associação Genômica Ampla , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Lectinas Tipo C/metabolismo , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Análise da Randomização Mendeliana , Nasofaringe/imunologia , Nasofaringe/patologia , Nasofaringe/virologia , RNA-Seq , Receptores de Superfície Celular/metabolismo , Índice de Gravidade de Doença , Análise de Célula Única
2.
Medicine (Baltimore) ; 100(35): e27125, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477155

RESUMO

ABSTRACT: We aimed to investigate the genetic and demographic differences and interactions between areas where observed genomic variations in Mycobacterium tuberculosis (M. tb) were distributed uniformly in cold and hot spots.The cold and hot spot areas were identified using the reported incidence of TB over the previous 5 years. Whole genome sequencing was performed on 291 M. tb isolates between January and June 2018. Analysis of molecular variance and a multifactor dimensionality reduction (MDR) model was applied to test gene-gene-environment interactions. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were computed to test the extent to which genetic mutation affects the TB epidemic using a multivariate logistic regression model.The percentage of the Beijing family strain in hot spots was significantly higher than that in cold spots (64.63% vs 50.69%, P = .022), among the elderly, people with a low BMI, and those having a history of contact with a TB patient (all P < .05). Individuals from cold spot areas had a higher frequency of out-of-town traveling (P < .05). The mutation of Rv1186c, Rv3900c, Rv1508c, Rv0210, and an Intergenic Region (SNP site: 3847237) showed a significant difference between cold and hot spots. (P < .001). The MDR model displayed a clear negative interaction effect of age groups with BMI (interaction entropy: -3.55%) and mutation of Rv0210 (interaction entropy: -2.39%). Through the mutations of Rv0210 and BMI had a low independent effect (interaction entropy: -1.46%).Our data suggests a statistically significant role of age, BMI and the polymorphisms of Rv0210 genes in the transmission and development of M. tb. The results provide clues for the study of susceptibility genes of M. tb in different populations. The characteristic strains showed a local epidemic. Strengthening genotype monitoring of strains in various regions can be used as an early warning signal of epidemic spillover.


Assuntos
Interações Hospedeiro-Patógeno/genética , Mycobacterium tuberculosis/genética , Tuberculose/microbiologia , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose/epidemiologia
3.
Medicine (Baltimore) ; 100(35): e27128, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477157

RESUMO

ABSTRACT: To examine the etiological distribution of pathogens in pediatric patients with severe pneumonia and analyze the drug resistance of major pathogen species.Nasopharyngeal secretion specimens were collected for bacterial culture from pediatric patients admitted to the Xiamen children's hospital who were diagnosed with severe pneumonia from January 2016 to December 2019. Pathogen species were detected by quantitative polymerase chain reaction, direct immunofluorescence, and bacterial culture and we examined the drug susceptibility of the bacterial pathogens.At least 1 species of the pathogen was detected in 576 of 734 patients and a total of 444 bacterial samples were isolated, of which 284 were gram-negative and 160 were gram-positive. The most frequently detected bacteria were Haemophilus influenzae, Streptococcus pneumonia, Staphylococcus aureus, Klebsiella pneumoniae, and Escherichia coli. In addition, we isolated 186 viral samples, of which the majority were respiratory syncytial virus (n = 90) and adenovirus (n = 70) as well as 142 Mycoplasma pneumonia samples.Gram-negative bacteria are dominant among the pathogens causing severe pneumonia in pediatric patients and the major pathogen species are resistant to a variety of antibiotics. Appropriate antibiotic use has an important role in preventing the emergence of resistant strains.


Assuntos
Farmacorresistência Bacteriana , Pneumonia/microbiologia , Adolescente , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Feminino , Interações Hospedeiro-Patógeno , Humanos , Lactente , Pacientes Internados/estatística & dados numéricos , Masculino , Pneumonia/tratamento farmacológico , Estudos Retrospectivos
4.
J Toxicol Sci ; 46(9): 425-435, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34470994

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). SARS-CoV-2 enters host cells by binding with the receptor angiotensin-converting enzyme 2 (ACE2). While ACE2 is expressed in multiple cell types, it has been implicated in the clinical progression of COVID-19 as an entry point for SARS-CoV-2 into respiratory cells. Human respiratory cells, such as airway and alveolar epithelial type II (ATII) cells, are considered essential for COVID-19 research; however, primary human respiratory cells are difficult to obtain. In the present study, we generated ATII and club cells from human induced pluripotent stem cells (hiPSCs) for SARS-CoV-2 infection and drug testing. The differentiated cells expressed ATII markers (SFTPB, SFTPC, ABCA3, SLC34A2) or club cell markers (SCGB1A1 and SCGB3A2). Differentiated cells, which express ACE2 and TMPRSS2, were infected with SARS-CoV-2. Remdesivir treatment decreased intracellular SARS-CoV-2 viral replication and, furthermore, treatment with bleomycin showed cytotoxicity in a concentration-dependent manner. These data suggest that hiPSC-derived AT2 and club cells provide a useful in vitro model for drug development.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Células Epiteliais Alveolares/efeitos dos fármacos , Antivirais/farmacologia , Bleomicina/toxicidade , Diferenciação Celular , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Testes de Toxicidade , Monofosfato de Adenosina/farmacologia , Alanina/farmacologia , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/virologia , COVID-19/tratamento farmacológico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Interações Hospedeiro-Patógeno , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Células-Tronco Pluripotentes Induzidas/virologia , Fenótipo , SARS-CoV-2/crescimento & desenvolvimento , SARS-CoV-2/patogenicidade , Replicação Viral/efeitos dos fármacos
5.
Molecules ; 26(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34500777

RESUMO

Human neutrophil elastase (HNE) is a uniquely destructive serine protease with the ability to unleash a wave of proteolytic activity by destroying the inhibitors of other proteases. Although this phenomenon forms an important part of the innate immune response to invading pathogens, it is responsible for the collateral host tissue damage observed in chronic conditions such as chronic obstructive pulmonary disease (COPD), and in more acute disorders such as the lung injuries associated with COVID-19 infection. Previously, a combinatorially selected activity-based probe revealed an unexpected substrate preference for oxidised methionine, which suggests a link to oxidative pathogen clearance by neutrophils. Here we use oxidised model substrates and inhibitors to confirm this observation and to show that neutrophil elastase is specifically selective for the di-oxygenated methionine sulfone rather than the mono-oxygenated methionine sulfoxide. We also posit a critical role for ordered solvent in the mechanism of HNE discrimination between the two oxidised forms methionine residue. Preference for the sulfone form of oxidised methionine is especially significant. While both host and pathogens have the ability to reduce methionine sulfoxide back to methionine, a biological pathway to reduce methionine sulfone is not known. Taken together, these data suggest that the oxidative activity of neutrophils may create rapidly cleaved elastase "super substrates" that directly damage tissue, while initiating a cycle of neutrophil oxidation that increases elastase tissue damage and further neutrophil recruitment.


Assuntos
Imunidade Inata , Elastase de Leucócito/metabolismo , Metionina/análogos & derivados , Neutrófilos/imunologia , Biocatálise , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Domínio Catalítico/genética , Ensaios Enzimáticos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Elastase de Leucócito/antagonistas & inibidores , Elastase de Leucócito/genética , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Metionina/metabolismo , Simulação de Dinâmica Molecular , Infiltração de Neutrófilos , Neutrófilos/enzimologia , Oxirredução/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/patologia , SARS-CoV-2/imunologia , Especificidade por Substrato/imunologia
6.
Cell Rep ; 36(7): 109530, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34380018

RESUMO

A recent study proposed that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) hijacks the LINE-1 (L1) retrotransposition machinery to integrate into the DNA of infected cells. If confirmed, this finding could have significant clinical implications. Here, we apply deep (>50×) long-read Oxford Nanopore Technologies (ONT) sequencing to HEK293T cells infected with SARS-CoV-2 and do not find the virus integrated into the genome. By examining ONT data from separate HEK293T cultivars, we completely resolve 78 L1 insertions arising in vitro in the absence of L1 overexpression systems. ONT sequencing applied to hepatitis B virus (HBV)-positive liver cancer tissues located a single HBV insertion. These experiments demonstrate reliable resolution of retrotransposon and exogenous virus insertions by ONT sequencing. That we find no evidence of SARS-CoV-2 integration suggests that such events are, at most, extremely rare in vivo and therefore are unlikely to drive oncogenesis or explain post-recovery detection of the virus.


Assuntos
COVID-19/virologia , DNA Viral/genética , Genoma Humano , SARS-CoV-2/genética , Análise de Sequência de DNA , Integração Viral , Idoso , Animais , COVID-19/diagnóstico , Carcinoma Hepatocelular/virologia , Chlorocebus aethiops , Células HEK293 , Vírus da Hepatite B/genética , Interações Hospedeiro-Patógeno , Humanos , Neoplasias Hepáticas/virologia , Elementos Nucleotídeos Longos e Dispersos , Masculino , Sequenciamento por Nanoporos , Células Vero
7.
Nat Commun ; 12(1): 5102, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429405

RESUMO

Range shifts of infectious plant disease are expected under climate change. As plant diseases move, emergent abiotic-biotic interactions are predicted to modify their distributions, leading to unexpected changes in disease risk. Evidence of these complex range shifts due to climate change, however, remains largely speculative. Here, we combine a long-term study of the infectious tree disease, white pine blister rust, with a six-year field assessment of drought-disease interactions in the southern Sierra Nevada. We find that climate change between 1996 and 2016 moved the climate optimum of the disease into higher elevations. The nonlinear climate change-disease relationship contributed to an estimated 5.5 (4.4-6.6) percentage points (p.p.) decline in disease prevalence in arid regions and an estimated 6.8 (5.8-7.9) p.p. increase in colder regions. Though climate change likely expanded the suitable area for blister rust by 777.9 (1.0-1392.9) km2 into previously inhospitable regions, the combination of host-pathogen and drought-disease interactions contributed to a substantial decrease (32.79%) in mean disease prevalence between surveys. Specifically, declining alternate host abundance suppressed infection probabilities at high elevations, even as climatic conditions became more suitable. Further, drought-disease interactions varied in strength and direction across an aridity gradient-likely decreasing infection risk at low elevations while simultaneously increasing infection risk at high elevations. These results highlight the critical role of aridity in modifying host-pathogen-drought interactions. Variation in aridity across topographic gradients can strongly mediate plant disease range shifts in response to climate change.


Assuntos
Basidiomycota , Mudança Climática , Doenças das Plantas , Ribes , Clima , Secas , Florestas , Interações Hospedeiro-Patógeno , Doenças das Plantas/microbiologia , Plantas , Prevalência , Água
8.
Indian J Pharmacol ; 53(4): 310-316, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34414910

RESUMO

Knowledge of a new mutant strain of SARS-coronavirus (CoV-2) is enormously essential to identify a targeted drug and for the development of the vaccine. In this article, we systematically reviewed the different mutation strains (variant of concern [VOC] and variant of interest [VOI]) which were found in different countries such as the UK, Singapore, China, Germany, Vietnam, Western Africa, Dublin, Ireland, Brazil, Iran, Italy, France, America, and Philippines. We searched four literature databases (PubMed, EMBASE, NATURE, and Willey online library) with suitable keywords and the time filter was November 2019 to June 16, 2021. To understand the worldwide spread of variants of SARS-CoV-2, we included a total of 27 articles of case reports, clinical and observational studies in the systematic review. However, these variants mostly spread because of their ability to increase transmission, virulence, and escape immunity. So, in this paper is we found mutated strains of SARS-CoV-2 like VOCs that are found in different regions across the globe are ALPHA strain in the U.K, BETA strain in South Africa, GAMMA strain in Brazil, Gamma and Beta strains in European Countries, and some VOIs like Theta variant in the Philippines.


Assuntos
COVID-19/virologia , Mutação , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiologia , Genótipo , Interações Hospedeiro-Patógeno , Humanos , Epidemiologia Molecular , SARS-CoV-2/patogenicidade
9.
Indian J Pharmacol ; 53(4): 317-327, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34414911

RESUMO

Since the onset of COVID-19 pandemic, parallel opportunistic infections have also been emerging as another disease spectrum. Among all these opportunistic infection, mucormycosis has become a matter of concern with its rapid increase of cases with rapid spread as compared to pre-COVID-19 era. Cases have been reported in post-COVID-19-related immune suppression along with the presence of comorbidity which adds on the deadly outcome. There is no systematic review addressing the issue of COVID-19-associated mucormycosis. This is the first systematic review of published studies of mucormycosis associated with COVID-19. The aim was to analyze the real scenario of the disease statement including all the published studies from first November 2019 to 30th June to analyze the contemporary epidemiology, clinical manifestations, risk factor, prognosis, and treatment outcome of COVID-19 associated rhino-orbito-cerebral-mucormycosis. A comprehensive literature search was done in following databases, namely, PubMed, Google Scholar, Scopus, and EMBASE using keywords mucormycosis, rhino orbital cerebral mucormycosis, COVID-19, and SARS-CoV-2 (from November 01, 2019 to June 30, 2021). Our study shows that, while corticosteroids have proved to be lifesaving in severe to critical COVID-19 patients, its indiscriminate use has come with its price of rhino-orbito-cerebral mucormycosis epidemic, especially in India especially in patients with preexisting diabetes mellitus with higher mortality. Corticosteroid use should be monitored and all COVID-19 patients should be closely evaluated/monitored for sequelae of immunosuppression following treatment.


Assuntos
COVID-19/virologia , Coinfecção , Meningite Fúngica/microbiologia , Mucormicose/microbiologia , Doenças Nasais/microbiologia , Infecções Oportunistas/microbiologia , Doenças Orbitárias/microbiologia , SARS-CoV-2/patogenicidade , Antifúngicos/uso terapêutico , COVID-19/imunologia , COVID-19/mortalidade , Interações Hospedeiro-Patógeno , Humanos , Meningite Fúngica/tratamento farmacológico , Meningite Fúngica/imunologia , Meningite Fúngica/mortalidade , Mucormicose/tratamento farmacológico , Mucormicose/imunologia , Mucormicose/mortalidade , Doenças Nasais/tratamento farmacológico , Doenças Nasais/imunologia , Doenças Nasais/mortalidade , Infecções Oportunistas/tratamento farmacológico , Infecções Oportunistas/imunologia , Infecções Oportunistas/mortalidade , Doenças Orbitárias/tratamento farmacológico , Doenças Orbitárias/imunologia , Doenças Orbitárias/mortalidade , Prognóstico , Medição de Risco , Fatores de Risco , SARS-CoV-2/imunologia
10.
Physiol Rep ; 9(17): e14998, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34448551

RESUMO

The spread of the novel coronavirus 2019 (COVID-19) has caused a global pandemic. The disease has spread rapidly, and research shows that COVID-19 can induce long-lasting cardiac damage. COVID-19 can result in elevated cardiac biomarkers indicative of acute cardiac injury, and research utilizing echocardiography has shown that there is mechanical dysfunction in these patients as well, especially when observing the isovolumic, systolic, and diastolic portions of the cardiac cycle. The purpose of this study was to present two case studies on COVID-19 positive patients who had their cardiac mechanical function assessed every day during the acute period to show that cardiac function in these patients was altered, and the damage occurring can change from day-to-day. Participant 1 showed compromised cardiac function in the systolic time, diastolic time, isovolumic time, and the calculated heart performance index (HPI), and these impairments were sustained even 23 days post-symptom onset. Furthermore, Participant 1 showed prolonged systolic periods that lasted longer than the diastolic periods, indicative of elevated pulmonary artery pressure. Participant 2 showed decreases in systole and consequently, increases in HPI during the 3 days post-symptom onset, and these changes returned to normal after day 4. These results showed that daily observation of cardiac function can provide detailed information about the overall mechanism by which cardiac dysfunction is occurring and that COVID-19 can induce cardiac damage in unique patterns and thus can be studied on a case-by-case basis, day-to-day during infection. This could allow us to move toward more personalized cardiovascular medical treatment.


Assuntos
COVID-19/fisiopatologia , Cardiopatias/fisiopatologia , Coração/fisiopatologia , Hemodinâmica , SARS-CoV-2/patogenicidade , Função Ventricular , Adulto , COVID-19/diagnóstico , COVID-19/virologia , Técnicas de Diagnóstico Cardiovascular/instrumentação , Coração/virologia , Cardiopatias/diagnóstico , Cardiopatias/virologia , Interações Hospedeiro-Patógeno , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Tempo , Transdutores
11.
Biochem Soc Trans ; 49(4): 1711-1721, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34351418

RESUMO

The COVID-19 pandemic has prompted intense research efforts into elucidating mechanisms of coronavirus pathogenesis and to propose antiviral interventions. The interferon (IFN) response is the main antiviral component of human innate immunity and is actively suppressed by several non-structural SARS-CoV-2 proteins, allowing viral replication within human cells. Differences in IFN signalling efficiency and timing have emerged as central determinants of the variability of COVID-19 disease severity between patients, highlighting the need for an improved understanding of host-pathogen interactions that affect the IFN response. ADP-ribosylation is an underexplored post-translational modification catalyzed by ADP-ribosyl transferases collectively termed poly(ADP-ribose) polymerases (PARPs). Several human PARPs are induced by the IFN response and participate in antiviral defences by regulating IFN signalling itself, modulating host processes such as translation and protein trafficking, as well as directly modifying and inhibiting viral target proteins. SARS-CoV-2 and other viruses encode a macrodomain that hydrolyzes ADP-ribose modifications, thus counteracting antiviral PARP activity. This mini-review provides a brief overview of the known targets of IFN-induced ADP-ribosylation and the functions of viral macrodomains, highlighting several open questions in the field.


Assuntos
ADP-Ribosilação , COVID-19/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , SARS-CoV-2/metabolismo , Interações Hospedeiro-Patógeno , Humanos , SARS-CoV-2/fisiologia
12.
PLoS One ; 16(8): e0256141, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34407143

RESUMO

SARS-CoV-2 requires serine protease, transmembrane serine protease 2 (TMPRSS2), and cysteine proteases, cathepsins B, L (CTSB/L) for entry into host cells. These host proteases activate the spike protein and enable SARS-CoV-2 entry. We herein performed genomic-guided gene set enrichment analysis (GSEA) to identify upstream regulatory elements altering the expression of TMPRSS2 and CTSB/L. Further, medicinal compounds were identified based on their effects on gene expression signatures of the modulators of TMPRSS2 and CTSB/L genes. Using this strategy, estradiol and retinoic acid have been identified as putative SARS-CoV-2 alleviation agents. Next, we analyzed drug-gene and gene-gene interaction networks using 809 human targets of SARS-CoV-2 proteins. The network results indicate that estradiol interacts with 370 (45%) and retinoic acid interacts with 251 (31%) human proteins. Interestingly, a combination of estradiol and retinoic acid interacts with 461 (56%) of human proteins, indicating the therapeutic benefits of drug combination therapy. Finally, molecular docking analysis suggests that both the drugs bind to TMPRSS2 and CTSL with the nanomolar to low micromolar affinity. The results suggest that these drugs can simultaneously target both the entry pathways of SARS-CoV-2 and thus can be considered as a potential treatment option for COVID-19.


Assuntos
Catepsina B/genética , Catepsina L/genética , Estradiol/farmacologia , Genômica/métodos , SARS-CoV-2/fisiologia , Serina Endopeptidases/genética , Tretinoína/farmacologia , Catepsina B/química , Catepsina L/química , Bases de Dados Genéticas , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Interações Hospedeiro-Patógeno , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Conformação Proteica , Mapas de Interação de Proteínas/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Serina Endopeptidases/química , Proteínas Virais/genética , Proteínas Virais/metabolismo , Internalização do Vírus/efeitos dos fármacos
13.
Cells ; 10(7)2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34359932

RESUMO

MicroRNAs (miRNAs) are critical regulators of gene expression that may be used to identify the pathological pathways influenced by disease and cellular interactions. Viral miRNAs (v-miRNAs) encoded by both DNA and RNA viruses induce immune dysregulation, virus production, and disease pathogenesis. Given the absence of effective treatment and the prevalence of highly infective SARS-CoV-2 strains, improved understanding of viral-associated miRNAs could provide novel mechanistic insights into the pathogenesis of COVID-19. In this study, SARS-CoV-2 v-miRNAs were identified by deep sequencing in infected Calu-3 and Vero E6 cell lines. Among the ~0.1% small RNA sequences mapped to the SARS-CoV-2 genome, the top ten SARS-CoV-2 v-miRNAs (including three encoded by the N gene; v-miRNA-N) were selected. After initial screening of conserved v-miRNA-N-28612, which was identified in both SARS-CoV and SARS-CoV-2, its expression was shown to be positively associated with viral load in COVID-19 patients. Further in silico analysis and synthetic-mimic transfection of validated SARS-CoV-2 v-miRNAs revealed novel functional targets and associations with mechanisms of cellular metabolism and biosynthesis. Our findings support the development of v-miRNA-based biomarkers and therapeutic strategies based on improved understanding of the pathophysiology of COVID-19.


Assuntos
COVID-19/metabolismo , Proteínas do Nucleocapsídeo de Coronavírus/genética , Redes e Vias Metabólicas , MicroRNAs/genética , RNA Viral/genética , SARS-CoV-2/fisiologia , Animais , COVID-19/virologia , Linhagem Celular , Chlorocebus aethiops , Interações Hospedeiro-Patógeno , Humanos , Fosfoproteínas/genética , SARS-CoV-2/genética , Células Vero
14.
Cells ; 10(7)2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34359986

RESUMO

A novel coronavirus discovered in 2019 is a new strain of the Coronaviridae family (CoVs) that had not been previously identified in humans. It is known as SARS-CoV-2 for Severe Acute Respiratory Syndrome Coronavirus-2, whilst COVID-19 is the name of the disease associated with the virus. SARS-CoV-2 emerged over one year ago and still haunts the human community throughout the world, causing both healthcare and socioeconomic problems. SARS-CoV-2 is spreading with many uncertainties about treatment and prevention: the data available are limited and there are few randomized controlled trial data on the efficacy of antiviral or immunomodulatory agents. SARS-CoV-2 and its mutants are considered as unique within the Coronaviridae family insofar as they spread rapidly and can have severe effects on health. Although the scientific world has been succeeding in developing vaccines and medicines to combat COVID-19, the appearance and the spread of new, more aggressive mutants are posing extra problems for treatment. Nevertheless, our understanding of pandemics is increasing significantly due to this outbreak and is leading to the development of many different pharmacological, immunological and other treatments. This Review focuses on a subset of COVID-19 research, primarily the cytoskeleton-related physiological and pathological processes in which coronaviruses such as SARS-CoV-2 are intimately involved. The discovery of the exact mechanisms of the subversion of host cells by SARS-CoV-2 is critical to the validation of specific drug targets and effective treatments.


Assuntos
Antivirais/farmacologia , COVID-19/patologia , Infecções por Coronaviridae/patologia , Citoesqueleto/patologia , Animais , Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , Infecções por Coronaviridae/tratamento farmacológico , Coronavirus/efeitos dos fármacos , Coronavirus/fisiologia , Citoesqueleto/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia
15.
Biomolecules ; 11(7)2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34356672

RESUMO

In the search for new therapeutic strategies to contrast SARS-CoV-2, we here studied the interaction of polydatin (PD) and resveratrol (RESV)-two natural stilbene polyphenols with manifold, well known biological activities-with Spike, the viral protein essential for virus entry into host cells, and ACE2, the angiotensin-converting enzyme present on the surface of multiple cell types (including respiratory epithelial cells) which is the main host receptor for Spike binding. Molecular Docking simulations evidenced that both compounds can bind Spike, ACE2 and the ACE2:Spike complex with good affinity, although the interaction of PD appears stronger than that of RESV on all the investigated targets. Preliminary biochemical assays revealed a significant inhibitory activity of the ACE2:Spike recognition with a dose-response effect only in the case of PD.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/tratamento farmacológico , Glucosídeos/farmacologia , Resveratrol/farmacologia , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/metabolismo , Estilbenos/farmacologia , COVID-19/metabolismo , Descoberta de Drogas , Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2/metabolismo
16.
Nat Commun ; 12(1): 4882, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385466

RESUMO

Genetic variants of the interferon lambda (IFNL) gene locus are strongly associated with spontaneous and IFN treatment-induced clearance of hepatitis C virus (HCV) infections. Individuals with the ancestral IFNL4-dG allele are not able to clear HCV in the acute phase and have more than a 90% probability to develop chronic hepatitis C (CHC). Paradoxically, the IFNL4-dG allele encodes a fully functional IFNλ4 protein with antiviral activity against HCV. Here we describe an effect of IFNλ4 on HCV antigen presentation. Only minor amounts of IFNλ4 are secreted, because the protein is largely retained in the endoplasmic reticulum (ER) where it induces ER stress. Stressed cells are significantly weaker activators of HCV specific CD8+ T cells than unstressed cells. This is not due to reduced MHC I surface presentation or extracellular IFNλ4 effects, since T cell responses are restored by exogenous loading of MHC with HCV antigens. Rather, IFNλ4 induced ER stress impairs HCV antigen processing and/or loading onto the MHC I complex. Our results provide a potential explanation for the IFNλ4-HCV paradox.


Assuntos
Apresentação do Antígeno/imunologia , Linfócitos T CD8-Positivos/imunologia , Hepacivirus/imunologia , Interleucinas/imunologia , Ativação Linfocitária/imunologia , Células A549 , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Linhagem Celular Tumoral , Regulação da Expressão Gênica/imunologia , Genótipo , Células Hep G2 , Hepacivirus/genética , Hepacivirus/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Interleucinas/genética , Interleucinas/metabolismo
17.
Nat Commun ; 12(1): 4917, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389714

RESUMO

APOBEC3A is a cytidine deaminase driving mutagenesis in tumors. While APOBEC3A-induced mutations are common, APOBEC3A expression is rarely detected in cancer cells. This discrepancy suggests a tightly controlled process to regulate episodic APOBEC3A expression in tumors. In this study, we find that both viral infection and genotoxic stress transiently up-regulate APOBEC3A and pro-inflammatory genes using two distinct mechanisms. First, we demonstrate that STAT2 promotes APOBEC3A expression in response to foreign nucleic acid via a RIG-I, MAVS, IRF3, and IFN-mediated signaling pathway. Second, we show that DNA damage and DNA replication stress trigger a NF-κB (p65/IkBα)-dependent response to induce expression of APOBEC3A and other innate immune genes, independently of DNA or RNA sensing pattern recognition receptors and the IFN-signaling response. These results not only reveal the mechanisms by which tumors could episodically up-regulate APOBEC3A but also highlight an alternative route to stimulate the immune response after DNA damage independently of cGAS/STING or RIG-I/MAVS.


Assuntos
Citidina Desaminase/genética , Dano ao DNA , Regulação da Expressão Gênica , Imunidade/genética , Proteínas/genética , Transdução de Sinais/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Citidina Desaminase/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células THP-1 , Fator de Transcrição RelA/metabolismo , Regulação para Cima , Vírus/crescimento & desenvolvimento
18.
J Gen Virol ; 102(8)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34424156

RESUMO

Viruses may exploit the cardiovascular system to facilitate transmission or within-host dissemination, and the symptoms of many viral diseases stem at least in part from a loss of vascular integrity. The microvascular architecture is comprised of an endothelial cell barrier ensheathed by perivascular cells (pericytes). Pericytes are antigen-presenting cells (APCs) and play crucial roles in angiogenesis and the maintenance of microvascular integrity through complex reciprocal contact-mediated and paracrine crosstalk with endothelial cells. We here review the emerging ways that viruses interact with pericytes and pay consideration to how these interactions influence microvascular function and viral pathogenesis. Major outcomes of virus-pericyte interactions include vascular leakage or haemorrhage, organ tropism facilitated by barrier disruption, including viral penetration of the blood-brain barrier and placenta, as well as inflammatory, neurological, cognitive and developmental sequelae. The underlying pathogenic mechanisms may include direct infection of pericytes, pericyte modulation by secreted viral gene products and/or the dysregulation of paracrine signalling from or to pericytes. Viruses we cover include the herpesvirus human cytomegalovirus (HCMV, Human betaherpesvirus 5), the retrovirus human immunodeficiency virus (HIV; causative agent of acquired immunodeficiency syndrome, AIDS, and HIV-associated neurocognitive disorder, HAND), the flaviviruses dengue virus (DENV), Japanese encephalitis virus (JEV) and Zika virus (ZIKV), and the coronavirus severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2; causative agent of coronavirus disease 2019, COVID-19). We touch on promising pericyte-focussed therapies for treating the diseases caused by these important human pathogens, many of which are emerging viruses or are causing new or long-standing global pandemics.


Assuntos
Fenômenos Fisiológicos Celulares , Suscetibilidade a Doenças , Interações Hospedeiro-Patógeno , Pericitos/virologia , Viroses/metabolismo , Viroses/virologia , Animais , Comunicação Celular , Vírus da Dengue/fisiologia , Gerenciamento Clínico , Células Endoteliais/virologia , Endotélio/metabolismo , Endotélio/virologia , HIV/fisiologia , Humanos , Comunicação Parácrina , SARS-CoV-2/fisiologia , Viroses/diagnóstico , Viroses/terapia , Fenômenos Fisiológicos Virais
19.
Sci Immunol ; 6(62)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376481

RESUMO

To understand how a protective immune response against SARS-CoV-2 develops over time, we integrated phenotypic, transcriptional and repertoire analyses on PBMCs from mild and severe COVID-19 patients during and after infection, and compared them to healthy donors (HD). A type I IFN-response signature marked all the immune populations from severe patients during the infection. Humoral immunity was dominated by IgG production primarily against the RBD and N proteins, with neutralizing antibody titers increasing post infection and with disease severity. Memory B cells, including an atypical FCRL5+ T-BET+ memory subset, increased during the infection, especially in patients with mild disease. A significant reduction of effector memory, CD8+ T cells frequency characterized patients with severe disease. Despite such impairment, we observed robust clonal expansion of CD8+ T lymphocytes, while CD4+ T cells were less expanded and skewed toward TCM and TH2-like phenotypes. MAIT cells were also expanded, but only in patients with mild disease. Terminally differentiated CD8+ GZMB+ effector cells were clonally expanded both during the infection and post-infection, while CD8+ GZMK+ lymphocytes were more expanded post-infection and represented bona fide memory precursor effector cells. TCR repertoire analysis revealed that only highly proliferating T cell clonotypes, which included SARS-CoV-2-specific cells, were maintained post-infection and shared between the CD8+ GZMB+ and GZMK+ subsets. Overall, this study describes the development of immunity against SARS-CoV-2 and identifies an effector CD8+ T cell population with memory precursor-like features.


Assuntos
COVID-19/genética , COVID-19/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunofenotipagem , SARS-CoV-2/imunologia , Transcriptoma , Adulto , Idoso , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores , COVID-19/virologia , Plasticidade Celular/genética , Plasticidade Celular/imunologia , Evolução Clonal/imunologia , Feminino , Perfilação da Expressão Gênica , Humanos , Isotipos de Imunoglobulinas/imunologia , Memória Imunológica , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
20.
Blood Cancer J ; 11(8): 142, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376633

RESUMO

This study evaluated the safety and immunogenicity of BNT162b2 vaccine in patients with hematological malignancies. Antibodies blocking spike binding to immobilized ACE-2 (NAb) correlated with anti-Spike (S) IgG d42 titers (Spearman r = 0.865, p < 0.0001), and an anti-S IgG d42 level ≥3100 UA/mL was predictive of NAb ≥ 30%, the positivity cutoff for NAb (p < 0.0001). Only 47% of the patients achieved an anti-S IgG d42 level ≥3100 UA/mL after the two BNT162b2 inocula, compared to 87% of healthy controls. In multivariable analysis, male patients, use of B-cell targeting treatment within the last 12 months prior to vaccination, and CD19+ B-cell level <120/uL, were associated with a significantly decreased probability of achieving a protective anti-S IgG level after the second BNT162b2 inoculum. Finally, using the IFN-γ ELISPOT assay, we found a significant increase in T-cell response against the S protein, with 53% of patients having an anti-S IgG-positive ELISPOT after the second BNT162b2 inoculum. There was a correlation between the anti-S ELISPOT response and IgG d42 level (Spearman r = 0.3026, p = 0.012). These findings suggest that vaccination with two BNT162b2 inocula translates into a significant increase in humoral and cellular response in patients with hematological malignancies, but only around half of the patients can likely achieve effective immune protection against COVID-19.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/complicações , COVID-19/imunologia , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/imunologia , Imunogenicidade da Vacina , SARS-CoV-2/imunologia , Imunidade Adaptativa , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/administração & dosagem , Comorbidade , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Linfócitos T/imunologia , Linfócitos T/metabolismo , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...