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1.
Physiol Rep ; 9(2): e14707, 2021 01.
Article in English | MEDLINE | ID: covidwho-1100461

ABSTRACT

The COVID-19 has originated from Wuhan, China, in December 2019 and has been affecting the public health system, society, and economy in an unheard-of manner. There is no specific treatment or vaccine available for COVID-19. Previous data showed that men are more affected than women by COVID-19, then we hypothesized whether sex hormones could be protecting the female organism against the infection. VERO E6 cells have been commonly used as in vitro model for SARS-CoV-2 infection. In our experimental approach, we have treated VERO E6 cells with 17ß-estradiol to evaluate the modulation of SARS-CoV-2 infection in this cell line. Here we demonstrated that estrogen protein receptors ERα, ERß, and GPER1 are expressed by VERO E6 cells and could be used to study the effects of this steroid hormone. Previous and 24-hours post-infection, cells treated with 17ß-estradiol revealed a reduction in the viral load. Afterward, we found that SARS-CoV-2 infection per se results in ACE2 and TMPRSS2 increased gene expression in VERO E6-cell, which could be generating a cycle of virus infection in host cells. The estrogen treatment reduces the levels of the TMPRSS2, which are involved with SARS-CoV-2 infectiveness capacity, and hence, reducing the pathogenicity/genesis. These data suggest that estrogen could be a potential therapeutic target promoting cell protection against SARS-CoV-2. This opens new possibilities for further studies on 17ß-estradiol in human cell lines infected by SARS-CoV-2 and at least in part, explain why men developed a more severe COVID-19 compared to women.


Subject(s)
Antiviral Agents/pharmacology , Estradiol/pharmacology , /drug effects , /genetics , Animals , /virology , Chlorocebus aethiops , Host-Pathogen Interactions , Receptors, Virus/genetics , Receptors, Virus/metabolism , Serine Endopeptidases/genetics , Serine Endopeptidases/metabolism , Vero Cells
2.
Life Sci Alliance ; 4(5)2021 05.
Article in English | MEDLINE | ID: covidwho-1089322

ABSTRACT

This study describes two complementary methods that use network-based and sequence similarity tools to identify drug repurposing opportunities predicted to modulate viral proteins. This approach could be rapidly adapted to new and emerging viruses. The first method built and studied a virus-host-physical interaction network; a three-layer multimodal network of drug target proteins, human protein-protein interactions, and viral-host protein-protein interactions. The second method evaluated sequence similarity between viral proteins and other proteins, visualized by constructing a virus-host-similarity interaction network. Methods were validated on the human immunodeficiency virus, hepatitis B, hepatitis C, and human papillomavirus, then deployed on SARS-CoV-2. Comparison of virus-host-physical interaction predictions to known antiviral drugs had AUCs of 0.69, 0.59, 0.78, and 0.67, respectively, reflecting that the scores are predictive of effective drugs. For SARS-CoV-2, 569 candidate drugs were predicted, of which 37 had been included in clinical trials for SARS-CoV-2 (AUC = 0.75, P-value 3.21 × 10-3). As further validation, top-ranked candidate antiviral drugs were analyzed for binding to protein targets in silico; binding scores generated by BindScope indicated a 70% success rate.


Subject(s)
Antiviral Agents/therapeutic use , Drug Repositioning , Systems Biology , Antiviral Agents/pharmacology , Clinical Trials as Topic , Computer Simulation , Gene Ontology , Host-Pathogen Interactions/drug effects , Humans , ROC Curve , Viral Proteins/metabolism
3.
Nat Commun ; 12(1): 780, 2021 02 16.
Article in English | MEDLINE | ID: covidwho-1087442

ABSTRACT

Novel pathogenic coronaviruses - such as SARS-CoV and probably SARS-CoV-2 - arise by homologous recombination between co-infecting viruses in a single cell. Identifying possible sources of novel coronaviruses therefore requires identifying hosts of multiple coronaviruses; however, most coronavirus-host interactions remain unknown. Here, by deploying a meta-ensemble of similarity learners from three complementary perspectives (viral, mammalian and network), we predict which mammals are hosts of multiple coronaviruses. We predict that there are 11.5-fold more coronavirus-host associations, over 30-fold more potential SARS-CoV-2 recombination hosts, and over 40-fold more host species with four or more different subgenera of coronaviruses than have been observed to date at >0.5 mean probability cut-off (2.4-, 4.25- and 9-fold, respectively, at >0.9821). Our results demonstrate the large underappreciation of the potential scale of novel coronavirus generation in wild and domesticated animals. We identify high-risk species for coronavirus surveillance.


Subject(s)
Coronavirus/physiology , Host-Pathogen Interactions , Mammals/virology , Animals , Coronavirus Infections/virology , Humans , Models, Biological , Phylogeny , Recombination, Genetic/genetics , Reproducibility of Results
4.
Mol Syst Biol ; 17(2): e10188, 2021 02.
Article in English | MEDLINE | ID: covidwho-1084993

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global threat to human health and has compromised economic stability. In addition to the development of an effective vaccine, it is imperative to understand how SARS-CoV-2 hijacks host cellular machineries on a system-wide scale so that potential host-directed therapies can be developed. In situ proteome-wide abundance and thermal stability measurements using thermal proteome profiling (TPP) can inform on global changes in protein activity. Here we adapted TPP to high biosafety conditions amenable to SARS-CoV-2 handling. We discovered pronounced temporal alterations in host protein thermostability during infection, which converged on cellular processes including cell cycle, microtubule and RNA splicing regulation. Pharmacological inhibition of host proteins displaying altered thermal stability or abundance during infection suppressed SARS-CoV-2 replication. Overall, this work serves as a framework for expanding TPP workflows to globally important human pathogens that require high biosafety containment and provides deeper resolution into the molecular changes induced by SARS-CoV-2 infection.


Subject(s)
/metabolism , Host-Pathogen Interactions , Protein Stability , Viral Proteins/metabolism , Antiviral Agents/pharmacology , Humans , Proteome , /metabolism , Temperature , Virus Replication/drug effects
5.
World J Gastroenterol ; 27(5): 377-390, 2021 Feb 07.
Article in English | MEDLINE | ID: covidwho-1081093

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has undoubtedly revolutionized the whole globe and given a new point of view on respiratory tract infections. Nevertheless, coronavirus disease 2019 (COVID-19) cannot be perceived as a disease limited only to pneumonia with diverse severity. More and more reports have demonstrated a wide range of possible systemic symptoms, including hepatic complications. Liver injury has been observed in a significant proportion of patients, especially in those with a severe or critical illness. COVID-19 might provoke a deterioration of liver function in patients with already diagnosed chronic liver diseases and without pre-existing liver disorders. The deterioration of liver function worsens the prognosis, increases the risk of a severe course of SARS-CoV-2 infection and prolongs the hospital stay. In general, patients who develop liver dysfunction in COVID-19 are mainly males, elderly people, and those with higher body mass index. The underlying mechanisms for hepatic failure in patients infected with SARS-CoV-2 are still unclear, nevertheless liver damage appears to be directly connected with virus-induced cytopathic effects. A liver injury observed during hospitalization might be simultaneously caused by the use of potentially hepatotoxic drugs, mainly antiviral agents. This minireview focuses on a possible relationship between COVID-19 and the liver, potential molecular mechanisms of liver damage, the characteristics of liver injury and suggested factors predisposing to hepatic manifestations in COVID-19 patients.


Subject(s)
/complications , Liver Failure/virology , Antiviral Agents/adverse effects , /pathology , Gastrointestinal Tract/physiopathology , Host-Pathogen Interactions , Humans , Inflammation/complications , Liver/pathology , Liver Failure/chemically induced , Metabolic Syndrome/complications , Prognosis , /physiology
7.
Eur Respir Rev ; 30(159)2021 Mar 31.
Article in English | MEDLINE | ID: covidwho-1079203

ABSTRACT

Studies have pointed out that air pollution may be a contributing factor to the coronavirus disease 2019 (COVID-19) pandemic. However, the specific links between air pollution and severe acute respiratory syndrome-coronavirus-2 infection remain unclear. Here we provide evidence from in vitro, animal and human studies from the existing literature. Epidemiological investigations have related various air pollutants to COVID-19 morbidity and mortality at the population level, however, those studies suffer from several limitations. Air pollution may be linked to an increase in COVID-19 severity and lethality through its impact on chronic diseases, such as cardiopulmonary diseases and diabetes. Experimental studies have shown that exposure to air pollution leads to a decreased immune response, thus facilitating viral penetration and replication. Viruses may persist in air through complex interactions with particles and gases depending on: 1) chemical composition; 2) electric charges of particles; and 3) meteorological conditions such as relative humidity, ultraviolet (UV) radiation and temperature. In addition, by reducing UV radiation, air pollutants may promote viral persistence in air and reduce vitamin D synthesis. Further epidemiological studies are needed to better estimate the impact of air pollution on COVID-19. In vitro and in vivo studies are also strongly needed, in particular to more precisely explore the particle-virus interaction in air.


Subject(s)
Air Pollution/adverse effects , /virology , Environmental Exposure/adverse effects , /pathogenicity , Air Pollutants/adverse effects , Animals , /transmission , Host-Pathogen Interactions , Humans , Prognosis , Risk Assessment , Risk Factors , Severity of Illness Index
8.
Nat Commun ; 12(1): 961, 2021 02 11.
Article in English | MEDLINE | ID: covidwho-1078585

ABSTRACT

The global spread of SARS-CoV-2 is posing major public health challenges. One feature of SARS-CoV-2 spike protein is the insertion of multi-basic residues at the S1/S2 subunit cleavage site. Here, we find that the virus with intact spike (Sfull) preferentially enters cells via fusion at the plasma membrane, whereas a clone (Sdel) with deletion disrupting the multi-basic S1/S2 site utilizes an endosomal entry pathway. Using Sdel as model, we perform a genome-wide CRISPR screen and identify several endosomal entry-specific regulators. Experimental validation of hits from the CRISPR screen shows that host factors regulating the surface expression of angiotensin-converting enzyme 2 (ACE2) affect entry of Sfull virus. Animal-to-animal transmission with the Sdel virus is reduced compared to Sfull in the hamster model. These findings highlight the critical role of the S1/S2 boundary of SARS-CoV-2 spike protein in modulating virus entry and transmission and provide insights into entry of coronaviruses.


Subject(s)
/virology , CRISPR-Cas Systems , Genome-Wide Association Study , Host-Pathogen Interactions , Virus Internalization , A549 Cells , /metabolism , Animals , Chlorocebus aethiops , Disease Models, Animal , Endosomes/virology , HeLa Cells , Humans , Mesocricetus , Serine Endopeptidases , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells
9.
Biosci Rep ; 41(2)2021 02 26.
Article in English | MEDLINE | ID: covidwho-1072179

ABSTRACT

The outbreak of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a global catastrophe. The elderly and people with comorbidity are facing a serious complication of the disease. The entry and infection strategy of SARS-CoV-2 in a host cell is raised by an amazing way of angiotensin-converting enzyme (ACE) 2 (ACE2) receptor recognition and imbalance of ACE/ACE2 in various organs, especially in the lungs. Here it has been discussed the role of interferon and protease during the receptor recognition (begining of infection) and followed by the impact of cytokine and hypoxia in the context of the balance of ACE/ACE2. It has also very concisely delineated the biochemistry and mechanism of ACE/ACE2 balance in different stages of infection and its role in comorbidity.


Subject(s)
/blood , /etiology , Peptidyl-Dipeptidase A/blood , /pathogenicity , Angiotensin Receptor Antagonists/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Comorbidity , Cytokines/metabolism , Host-Pathogen Interactions , Humans , Renin-Angiotensin System/physiology , Virus Internalization
10.
Front Immunol ; 11: 610024, 2020.
Article in English | MEDLINE | ID: covidwho-1069721

ABSTRACT

In contrast to other pathogenic agents that directly destroy host cells and tissues, the lethal power of SARS-CoV-2 resides in the over-reactive immune response triggered by this virus. Based on numerous evidences indicating that the lipid composition of host membranes is dramatically affected by COVID-19, and in the fact that our endogenous antimicrobial peptides (AMPs) are sensitive to the membrane composition of pathogenic agents, we propose that such destructive immune response is due to the direct action of AMPs. In a scenario where most host cell membranes are dressed by a pathogenic lipid composition, AMPs can indiscriminately attack them. This is why we use the "AMP betrayal" term to describe this mechanism. Previously proposed cytokine/bradykinin storm mechanisms are not incompatible with this new proposal. Interestingly, the harmful action of AMPs could be prevented by new therapies aimed to reestablish the lipid composition or to inhibit the action of specific peptides.


Subject(s)
/immunology , Cytokine Release Syndrome/immunology , Inflammation/immunology , /immunology , Apoptosis , Cytokines/metabolism , Host-Pathogen Interactions , Humans , Pore Forming Cytotoxic Proteins/metabolism
11.
Nat Commun ; 12(1): 866, 2021 02 08.
Article in English | MEDLINE | ID: covidwho-1069107

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly become a global public health threat. The efficacy of several repurposed drugs has been evaluated in clinical trials. Among these drugs, a second-generation antiandrogen agent, enzalutamide, was proposed because it reduces the expression of transmembrane serine protease 2 (TMPRSS2), a key component mediating SARS-CoV-2-driven entry, in prostate cancer cells. However, definitive evidence for the therapeutic efficacy of enzalutamide in COVID-19 is lacking. Here, we evaluated the antiviral efficacy of enzalutamide in prostate cancer cells, lung cancer cells, human lung organoids and Ad-ACE2-transduced mice. Tmprss2 knockout significantly inhibited SARS-CoV-2 infection in vivo. Enzalutamide effectively inhibited SARS-CoV-2 infection in human prostate cells, however, such antiviral efficacy was lacking in human lung cells and organoids. Accordingly, enzalutamide showed no antiviral activity due to the AR-independent TMPRSS2 expression in mouse and human lung epithelial cells. Moreover, we observed distinct AR binding patterns between prostate cells and lung cells and a lack of direct binding of AR to TMPRSS2 regulatory locus in human lung cells. Thus, our findings do not support the postulated protective role of enzalutamide in treating COVID-19 through reducing TMPRSS2 expression in lung cells.


Subject(s)
/prevention & control , Organ Specificity/genetics , Phenylthiohydantoin/analogs & derivatives , Serine Endopeptidases/genetics , /genetics , Animals , /virology , Cell Line, Tumor , Cells, Cultured , Gene Expression/drug effects , Host-Pathogen Interactions/drug effects , Humans , Male , Mice, Knockout , Pandemics , Phenylthiohydantoin/pharmacology , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Prostatic Neoplasms/virology , Protein Binding/drug effects , Serine Endopeptidases/metabolism
12.
Cell ; 184(1): 120-132.e14, 2021 01 07.
Article in English | MEDLINE | ID: covidwho-1064914

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has claimed the lives of over one million people worldwide. The causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a member of the Coronaviridae family of viruses that can cause respiratory infections of varying severity. The cellular host factors and pathways co-opted during SARS-CoV-2 and related coronavirus life cycles remain ill defined. To address this gap, we performed genome-scale CRISPR knockout screens during infection by SARS-CoV-2 and three seasonal coronaviruses (HCoV-OC43, HCoV-NL63, and HCoV-229E). These screens uncovered host factors and pathways with pan-coronavirus and virus-specific functional roles, including major dependency on glycosaminoglycan biosynthesis, sterol regulatory element-binding protein (SREBP) signaling, bone morphogenetic protein (BMP) signaling, and glycosylphosphatidylinositol biosynthesis, as well as a requirement for several poorly characterized proteins. We identified an absolute requirement for the VMP1, TMEM41, and TMEM64 (VTT) domain-containing protein transmembrane protein 41B (TMEM41B) for infection by SARS-CoV-2 and three seasonal coronaviruses. This human coronavirus host factor compendium represents a rich resource to develop new therapeutic strategies for acute COVID-19 and potential future coronavirus pandemics.


Subject(s)
Coronavirus Infections/genetics , Genome-Wide Association Study , /physiology , A549 Cells , Cell Line , Clustered Regularly Interspaced Short Palindromic Repeats , Coronavirus 229E, Human/physiology , Coronavirus Infections/virology , Coronavirus NL63, Human/physiology , Coronavirus OC43, Human/physiology , Gene Knockout Techniques , HEK293 Cells , Host-Pathogen Interactions/drug effects , Humans , Membrane Proteins/metabolism , Metabolic Networks and Pathways/drug effects , Protein Interaction Mapping
13.
Cell ; 184(1): 106-119.e14, 2021 01 07.
Article in English | MEDLINE | ID: covidwho-1064913

ABSTRACT

The Coronaviridae are a family of viruses that cause disease in humans ranging from mild respiratory infection to potentially lethal acute respiratory distress syndrome. Finding host factors common to multiple coronaviruses could facilitate the development of therapies to combat current and future coronavirus pandemics. Here, we conducted genome-wide CRISPR screens in cells infected by SARS-CoV-2 as well as two seasonally circulating common cold coronaviruses, OC43 and 229E. This approach correctly identified the distinct viral entry factors ACE2 (for SARS-CoV-2), aminopeptidase N (for 229E), and glycosaminoglycans (for OC43). Additionally, we identified phosphatidylinositol phosphate biosynthesis and cholesterol homeostasis as critical host pathways supporting infection by all three coronaviruses. By contrast, the lysosomal protein TMEM106B appeared unique to SARS-CoV-2 infection. Pharmacological inhibition of phosphatidylinositol kinases and cholesterol homeostasis reduced replication of all three coronaviruses. These findings offer important insights for the understanding of the coronavirus life cycle and the development of host-directed therapies.


Subject(s)
/genetics , Coronavirus Infections/genetics , Coronavirus/physiology , Genome-Wide Association Study , Host-Pathogen Interactions , /physiology , A549 Cells , Animals , Biosynthetic Pathways/drug effects , Cell Line , Chlorocebus aethiops , Cholesterol/biosynthesis , Cholesterol/metabolism , Cluster Analysis , Clustered Regularly Interspaced Short Palindromic Repeats , Common Cold/genetics , Common Cold/virology , Coronavirus/classification , Coronavirus Infections/virology , Gene Knockout Techniques , Host-Pathogen Interactions/drug effects , Humans , Mice , Phosphatidylinositols/biosynthesis , Vero Cells , Virus Internalization/drug effects , Virus Replication
14.
Immun Inflamm Dis ; 9(1): 48-58, 2021 03.
Article in English | MEDLINE | ID: covidwho-1064362

ABSTRACT

BACKGROUND: Although coronavirus disease 2019 (COVID-19) has been associated primarily with pneumonia, recent data show that the causative agent of COVID-19, the coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can infect a large number of vital organs beyond the lungs, such as the heart, kidneys, and the brain. Thus, there is evidence showing possible retrograde transmission of the virus from the olfactory epithelium to regions of the brain stem. METHODS: This is a literature review article. The research design method is an evidence-based rapid review. The present discourse aim is first to scrutinize and assess the available literature on COVID-19 repercussion on the central nervous system (CNS). Standard literature and database searches were implemented, gathered relevant material, and extracted information was then assessed. RESULTS: The angiotensin-converting enzyme 2 (ACE2) receptors being the receptor for the virus, the threat to the central nervous system is expected. Neurons and glial cells express ACE2 receptors in the CNS, and recent studies suggest that activated glial cells contribute to neuroinflammation and the devastating effects of SARS-CoV-2 infection on the CNS. The SARS-CoV-2-induced immune-mediated demyelinating disease, cerebrovascular damage, neurodegeneration, and depression are some of the neurological complications discussed here. CONCLUSION: This review correlates present clinical manifestations of COVID-19 patients with possible neurological consequences in the future, thus preparing healthcare providers for possible future consequences of COVID-19.


Subject(s)
/complications , Nervous System Diseases/etiology , /physiology , Brain/metabolism , Brain/physiopathology , Brain/virology , Disease Susceptibility , Host-Pathogen Interactions , Humans , Nervous System/metabolism , Nervous System/physiopathology , Nervous System/virology , Nervous System Diseases/diagnosis
15.
Immun Inflamm Dis ; 9(1): 128-133, 2021 03.
Article in English | MEDLINE | ID: covidwho-1064359

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged throughout the world. Building knowledge around Covid-19 is crucial to devise facts based approaches to respond efficiently against this pandemic. AIM: We aimed to investigate pre-existing humoral cross-reactive immunity to SARS-CoV-2. METHOD: We have tested the reactivity against SARS-CoV-2 nucleocapsid (N) antigen of sera collected from healthy healthcare volunteers in 2014. We assessed immunoglobulins reactive against SARS-CoV-2 N-antigen using a well-validated serological platform; Elecsys assay. RESULTS: Sera from 32 subjects (out of 135 [23.7%]) were reactive to SARS-CoV-2 N-antigen, suggesting the presence of anti-SARS-CoV-2 N-antigen antibodies. CONCLUSION: Although the clinical relevance of the observed reactivity can only be speculated and needs to be investigated, the implication of this finding for coronavirus disease 2019 seroepidemiological survey and vaccines' clinical trials is critical.


Subject(s)
/immunology , Cross Reactions/immunology , Host-Pathogen Interactions/immunology , Immunity, Humoral , /immunology , Adult , Antibodies, Viral/blood , Antibodies, Viral/immunology , Female , Humans , Immunologic Memory , Male , Middle Aged , Seroepidemiologic Studies
16.
Drug Discov Ther ; 14(6): 262-272, 2021 Jan 23.
Article in English | MEDLINE | ID: covidwho-1067907

ABSTRACT

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified in 2019 in Wuhan, China. Clinically, respiratory tract symptoms as well as other organs disorders are observed in patients positively diagnosed coronavirus disease 2019 (COVID-19). In addition, neurological symptoms, mainly anosmia, ageusia and headache were observed in many patients. Once in the central nervous system (CNS), the SARS-CoV-2 can reside either in a quiescent latent state, or eventually in actively state leading to severe acute encephalitis, characterized by neuroinflammation and prolonged neuroimmune activation. SRAS-CoV-2 requires angiotensin-converting enzyme 2 (ACE2) as a cell entry receptor. The expression of this receptor in endothelial cells of blood-brain barrier (BBB) shows that SRAS-CoV-2 may have higher neuroinvasive potential compared to known coronaviruses. This review summarizes available information regarding the impact of SRAS-CoV-2 in the brain and tended to identify its potential pathways of neuroinvasion. We offer also an understanding of the long-term impact of latently form of SARS-CoV-2 on the development of neurodegenerative disorders. As a conclusion, the persistent infection of SRAS-CoV-2 in the brain could be involved on human neurodegenerative diseases that evolve a gradual process, perhapes, over several decades.


Subject(s)
/virology , Central Nervous System Viral Diseases/virology , Neurodegenerative Diseases/virology , Neurons/virology , Viral Tropism , Animals , Central Nervous System Viral Diseases/metabolism , Central Nervous System Viral Diseases/pathology , Host-Pathogen Interactions , Humans , Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/pathology , Neurons/metabolism , Neurons/pathology , Virus Latency
17.
Int J Mol Sci ; 22(3)2021 Jan 20.
Article in English | MEDLINE | ID: covidwho-1067752

ABSTRACT

The occurrence of the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), responsible for coronavirus disease 2019 (COVD-19), represents a catastrophic threat to global health. Protruding from the viral surface is a densely glycosylated spike (S) protein, which engages angiotensin-converting enzyme 2 (ACE2) to mediate host cell entry. However, studies have reported viral susceptibility in intra- and extrapulmonary immune and non-immune cells lacking ACE2, suggesting that the S protein may exploit additional receptors for infection. Studies have demonstrated interactions between S protein and innate immune system, including C-lectin type receptors (CLR), toll-like receptors (TLR) and neuropilin-1 (NRP1), and the non-immune receptor glucose regulated protein 78 (GRP78). Recognition of carbohydrate moieties clustered on the surface of the S protein may drive receptor-dependent internalization, accentuate severe immunopathological inflammation, and allow for systemic spread of infection, independent of ACE2. Furthermore, targeting TLRs, CLRs, and other receptors (Ezrin and dipeptidyl peptidase-4) that do not directly engage SARS-CoV-2 S protein, but may contribute to augmented anti-viral immunity and viral clearance, may represent therapeutic targets against COVID-19.


Subject(s)
/metabolism , /physiology , Virus Internalization , /immunology , Animals , Disease Progression , Heat-Shock Proteins/immunology , Heat-Shock Proteins/metabolism , Host-Pathogen Interactions , Humans , Lectins, C-Type/immunology , Lectins, C-Type/metabolism , Neuropilin-1/immunology , Neuropilin-1/metabolism , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Toll-Like Receptors/immunology , Toll-Like Receptors/metabolism
18.
PLoS One ; 16(2): e0244127, 2021.
Article in English | MEDLINE | ID: covidwho-1067399

ABSTRACT

INTRODUCTION: Olfactory dysfunction (OD) affects a majority of COVID-19 patients, is atypical in duration and recovery, and is associated with focal opacification and inflammation of the olfactory epithelium. Given recent increased emphasis on airborne transmission of SARS-CoV-2, the purpose of the present study was to experimentally characterize aerosol dispersion within olfactory epithelium (OE) and respiratory epithelium (RE) in human subjects, to determine if small (sub 5µm) airborne aerosols selectively deposit in the OE. METHODS: Healthy adult volunteers inhaled fluorescein-labeled nebulized 0.5-5µm airborne aerosol or atomized larger aerosolized droplets (30-100µm). Particulate deposition in the OE and RE was assessed by blue-light filter modified rigid endoscopic evaluation with subsequent image randomization, processing and quantification by a blinded reviewer. RESULTS: 0.5-5µm airborne aerosol deposition, as assessed by fluorescence gray value, was significantly higher in the OE than the RE bilaterally, with minimal to no deposition observed in the RE (maximum fluorescence: OE 19.5(IQR 22.5), RE 1(IQR 3.2), p<0.001; average fluorescence: OE 2.3(IQR 4.5), RE 0.1(IQR 0.2), p<0.01). Conversely, larger 30-100µm aerosolized droplet deposition was significantly greater in the RE than the OE (maximum fluorescence: OE 13(IQR 14.3), RE 38(IQR 45.5), p<0.01; average fluorescence: OE 1.9(IQR 2.1), RE 5.9(IQR 5.9), p<0.01). CONCLUSIONS: Our data experimentally confirm that despite bypassing the majority of the upper airway, small-sized (0.5-5µm) airborne aerosols differentially deposit in significant concentrations within the olfactory epithelium. This provides a compelling aerodynamic mechanism to explain atypical OD in COVID-19.


Subject(s)
Aerosols/analysis , /complications , Olfactory Mucosa/physiopathology , Adult , Aerosols/administration & dosage , /virology , /virology , Host-Pathogen Interactions , Humans , Olfactory Mucosa/virology , Smell
19.
J Diabetes Res ; 2021: 9526701, 2021.
Article in English | MEDLINE | ID: covidwho-1066964

ABSTRACT

The induction of inflammation and cytokine storm was proposed to play a critical role in COVID-19. This study is aimed at investigating the relationship between glucose metabolism and the inflammatory state of inpatients with COVID-19. 71 inpatients with COVID-19 were classified into nondiabetes mellitus (NDM) group, impaired fasting glucose (IFG) group, and diabetes mellitus (DM) group. The average hospitalization days were significantly shorter in DM patients when compared with patients in the IFG group and NDM group. CD4+ T cell percentage was higher while CD8+ T cells percentage was lower in the DM group than those in the NDM group. The serum levels of IL-6, IL-2, IL-10, and INF-γ in the DM group were upregulated when compared with those in the NDM group. The serum levels of TNF-α, IL-4, IL-2, IL-10, and INF-γ were significantly higher in the DM group than those in the IFG group. A significant difference was observed in CD4+ T cell, CD4+/CD8+ ratio percentage, IL-6, and IL-10 between the NDM group and DM group with adjusted BMI. In conclusion, COVID-19 patients with elevated glucose levels have promoted cytokine profiles and immune response.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cytokines/immunology , Diabetes Mellitus, Type 2/immunology , Inflammation Mediators/immunology , /immunology , Adult , Aged , Biomarkers/blood , Blood Glucose/metabolism , CD4-Positive T-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/virology , CD8-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/virology , /epidemiology , Cytokines/blood , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/epidemiology , Female , Host-Pathogen Interactions , Humans , Inflammation Mediators/blood , Length of Stay , Male , Middle Aged , Prognosis , Time Factors
20.
J Clin Gastroenterol ; 55(3): 187-194, 2021 03 01.
Article in English | MEDLINE | ID: covidwho-1066465

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has brought challenges to clinicians caring for patients with chronic liver disease. In the past 6 months, COVID-19 has led to over 150,000 deaths in the United States and over 660,000 deaths around the world. Mounting evidence suggests that chronic liver diseases can have an adverse effect on the clinical outcomes of patients with COVID-19. We present a comprehensive review of the latest literature on preexisting liver diseases and its interrelationship with COVID-19 infection in cirrhosis, hepatocellular carcinoma, nonalcoholic fatty liver disease, autoimmune hepatitis, and viral hepatitis B. As social distancing and telemedicine gain new footing, we synthesize recommendations from 3 major hepatology societies [American Association for the Study of Liver Disease (AASLD), the European Association for the Study of Liver (EASL), and the Asian Pacific Association for the Study of Liver (APASL)] to present the best approaches for caring for patients with liver diseases as well as those requiring liver transplantation.


Subject(s)
/therapy , Liver Diseases/surgery , Liver Transplantation , Liver/surgery , /pathogenicity , /diagnosis , /virology , Health Status , Host-Pathogen Interactions , Humans , Immunocompromised Host , Immunosuppressive Agents/adverse effects , Liver/virology , Liver Diseases/diagnosis , Liver Diseases/mortality , Liver Diseases/virology , Liver Transplantation/adverse effects , Liver Transplantation/mortality , Risk Assessment , Risk Factors , Treatment Outcome
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