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1.
Nat Biomed Eng ; 6(3): 286-297, 2022 03.
Article in English | MEDLINE | ID: covidwho-1751719

ABSTRACT

CRISPR-based assays for the detection of nucleic acids are highly specific, yet they are not fast, sensitive or easy to use. Here we report a one-step fluorescence assay for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in nasopharyngeal samples, with a sample-to-answer time of less than 20 minutes and a sensitivity comparable to that of quantitative real-time PCR with reverse transcription (RT-qPCR). The assay uses suboptimal protospacer adjacent motifs, allowing for flexibility in the design of CRISPR RNAs and slowing down the kinetics of Cas12a-mediated collateral cleavage of fluorescent DNA reporters and cis cleavage of substrates, which leads to stronger fluorescence owing to the accumulation of amplicons generated by isothermal recombinase polymerase amplification. In a set of 204 nasopharyngeal samples with RT-qPCR cycle thresholds ranging from 18.1 to 35.8, the assay detected SARS-CoV-2 with a sensitivity of 94.2% and a specificity of 100%, without the need for RNA extraction. Rapid and sensitive assays for nucleic acid testing in one pot that allow for flexibility in assay design may aid the development of reliable point-of-care nucleic acid testing.


Subject(s)
COVID-19 , RNA, Viral , COVID-19/diagnosis , CRISPR-Cas Systems , Humans , RNA, Viral/genetics , SARS-CoV-2/genetics , Sensitivity and Specificity
2.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-319519

ABSTRACT

Multiorgan injuries are a major complication of severe COVID-19;however, its pathogenesis is barely understood. Herein, we profiled the host responses to SARS-CoV-2 infection by performing quantitative proteomics of COVID-19 postmortem samples, and provided a comprehensive proteome map covering the protein alterations in eight different organs/tissues. Our results revealed that lung underwent the most abundant protein alterations mainly enriched in immune-/inflammation-related or morphology-related processes, while surprisingly, other organs/tissues exhibited significant protein alterations mainly enriched in processes related with organ movement, respiration, and metabolism. These results indicate that the major cause of lung injury was excessive inflammatory response, and subsequent intravascular thrombosis and pulmonary architecture/function destruction, while other organs/tissues were mainly injured by hypoxia and functional impairment. Therefore, our findings demonstrate the significant pathophysiological alternations of host proteins/pathways associated with multiorgan injuries of COVID-19, which provides invaluable knowledge about COVID-19-associated host responses and sheds light on the pathogenesis of COVID-19.

3.
Cell Res ; 31(8): 836-846, 2021 08.
Article in English | MEDLINE | ID: covidwho-1275907

ABSTRACT

Severe COVID-19 disease caused by SARS-CoV-2 is frequently accompanied by dysfunction of the lungs and extrapulmonary organs. However, the organotropism of SARS-CoV-2 and the port of virus entry for systemic dissemination remain largely unknown. We profiled 26 COVID-19 autopsy cases from four cohorts in Wuhan, China, and determined the systemic distribution of SARS-CoV-2. SARS-CoV-2 was detected in the lungs and multiple extrapulmonary organs of critically ill COVID-19 patients up to 67 days after symptom onset. Based on organotropism and pathological features of the patients, COVID-19 was divided into viral intrapulmonary and systemic subtypes. In patients with systemic viral distribution, SARS-CoV-2 was detected in monocytes, macrophages, and vascular endothelia at blood-air barrier, blood-testis barrier, and filtration barrier. Critically ill patients with long disease duration showed decreased pulmonary cell proliferation, reduced viral RNA, and marked fibrosis in the lungs. Permanent SARS-CoV-2 presence and tissue injuries in the lungs and extrapulmonary organs suggest direct viral invasion as a mechanism of pathogenicity in critically ill patients. SARS-CoV-2 may hijack monocytes, macrophages, and vascular endothelia at physiological barriers as the ports of entry for systemic dissemination. Our study thus delineates systemic pathological features of SARS-CoV-2 infection, which sheds light on the development of novel COVID-19 treatment.


Subject(s)
COVID-19/pathology , Lung/virology , SARS-CoV-2/isolation & purification , Aged , Aged, 80 and over , Autopsy , COVID-19/virology , China , Cohort Studies , Critical Illness , Female , Fibrosis , Hospitalization , Humans , Kidney/pathology , Kidney/virology , Leukocytes, Mononuclear/pathology , Leukocytes, Mononuclear/virology , Lung/pathology , Male , Middle Aged , RNA, Viral/metabolism , SARS-CoV-2/genetics , Spleen/pathology , Spleen/virology , Trachea/pathology , Trachea/virology
5.
Natl Sci Rev ; 7(7): 1157-1168, 2020 Jul.
Article in English | MEDLINE | ID: covidwho-1114858

ABSTRACT

The pandemic of the coronavirus disease 2019 (COVID-19) has become a global public health crisis. The symptoms of COVID-19 range from mild to severe, but the physiological changes associated with COVID-19 are barely understood. In this study, we performed targeted metabolomic and lipidomic analyses of plasma from a cohort of patients with COVID-19 who had experienced different symptoms. We found that metabolite and lipid alterations exhibit apparent correlation with the course of disease in these patients, indicating that the development of COVID-19 affected their whole-body metabolism. In particular, malic acid of the TCA cycle and carbamoyl phosphate of the urea cycle result in altered energy metabolism and hepatic dysfunction, respectively. It should be noted that carbamoyl phosphate is profoundly down-regulated in patients who died compared with patients with mild symptoms. And, more importantly, guanosine monophosphate (GMP), which is mediated not only by GMP synthase but also by CD39 and CD73, is significantly changed between healthy subjects and patients with COVID-19, as well as between the mild and fatal cases. In addition, dyslipidemia was observed in patients with COVID-19. Overall, the disturbed metabolic patterns have been found to align with the progress and severity of COVID-19. This work provides valuable knowledge about plasma biomarkers associated with COVID-19 and potential therapeutic targets, as well as an important resource for further studies of the pathogenesis of COVID-19.

6.
Curr Med Sci ; 41(1): 39-45, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-1084651

ABSTRACT

Infection-associated hemophagocytic syndrome (IAHS), a severe complication of various infections, is potentially fatal. This study aims to determine whether IAHS occurs in critically ill patients with coronavirus disease 2019 (COVID-19). We conducted a retrospective observational study on 268 critically ill patients with COVID-19 between February 1st, 2020 and February 26th, 2020. Demographics, clinical characteristics, laboratory results, information on concurrent treatments and outcomes were collected. A diagnosis of secondary hemophagocytic lymphohistiocytosis (sHLH) was made when the patients had an HScore greater than 169. Histopathological examinations were performed to confirm the presence of hemophagocytosis. Of 268 critically ill patients with confirmed SARS-CoV-2 infection, 17 (6.3%) patients had an HScore greater than 169. All the 17 patients with sHLH died. The interval from the onset of symptom of COVID-19 to the time of a diagnosis of sHLH made was 19 days and the interval from the diagnosis of sHLH to death was 4 days. Ten (59%) patients were infected with only SARS-CoV-2. Hemophagocytosis in the spleen and the liver, as well as lymphocyte infiltration in the liver on histopathological examinations, was found in 3 sHLH autopsy patients. Mortality in sHLH patients with COVID-19 is high. And SARS-CoV-2 is a potential trigger for sHLH. Prompt recognition of IAHS in critically ill patients with COVID-19 could be beneficial for improving clinical outcomes.


Subject(s)
COVID-19/complications , Lymphohistiocytosis, Hemophagocytic/mortality , Adult , Aged , COVID-19/mortality , Critical Illness , Female , Humans , Lymphohistiocytosis, Hemophagocytic/etiology , Male , Middle Aged , Mortality , Prognosis , Retrospective Studies
7.
Front Microbiol ; 11: 600989, 2020.
Article in English | MEDLINE | ID: covidwho-1021898

ABSTRACT

SARS-coronavirus-2-induced immune dysregulation and inflammatory responses are involved in the pathogenesis of coronavirus disease-2019 (COVID-19). However, very little is known about immune cell and cytokine alterations in specific organs of COVID-19 patients. Here, we evaluated immune cells and cytokines in postmortem tissues, i.e., lungs, intestine, liver, kidneys, and spleen of three patients with COVID-19. Imaging mass cytometry revealed monocyte, macrophage, and dendritic cell (DC) infiltration in the lung, intestine, kidney, and liver tissues. Moreover, in patients with COVID-19, natural killer T cells infiltrated the liver, lungs, and intestine, whereas B cells infiltrated the kidneys, lungs, and intestine. CD11b+ macrophages and CD11c+ DCs also infiltrated the lungs and intestine, a phenomenon that was accompanied by overproduction of the immunosuppressive cytokine interleukin (IL)-10. However, CD11b+ macrophages and CD11c+ DCs in the lungs or intestine of COVID-19 patients did not express human leukocyte antigen DR isotype. In contrast, tumor necrosis factor (TNF)-α expression was higher in the lungs, intestine, liver, and kidneys, but not in the spleen, of all COVID-19 patients (compared to levels in controls). Collectively, these findings suggested that IL-10 and TNF-α as immunosuppressive and pro-inflammatory agents, respectively,-might be prognostic and could serve as therapeutic targets for COVID-19.

8.
Virol Sin ; 35(3): 321-329, 2020 Jun.
Article in English | MEDLINE | ID: covidwho-959357

ABSTRACT

The ongoing outbreak of Coronavirus Disease 2019 (COVID-19) has become a global public health emergency. SARS-coronavirus-2 (SARS-CoV-2), the causative pathogen of COVID-19, is a positive-sense single-stranded RNA virus belonging to the family Coronaviridae. For RNA viruses, virus-encoded RNA helicases have long been recognized to play pivotal roles during viral life cycles by facilitating the correct folding and replication of viral RNAs. Here, our studies show that SARS-CoV-2-encoded nonstructural protein 13 (nsp13) possesses the nucleoside triphosphate hydrolase (NTPase) and RNA helicase activities that can hydrolyze all types of NTPs and unwind RNA helices dependently of the presence of NTP, and further characterize the biochemical characteristics of these two enzymatic activities associated with SARS-CoV-2 nsp13. Moreover, we found that some bismuth salts could effectively inhibit both the NTPase and RNA helicase activities of SARS-CoV-2 nsp13 in a dose-dependent manner. Thus, our findings demonstrate the NTPase and helicase activities of SARS-CoV-2 nsp13, which may play an important role in SARS-CoV-2 replication and serve as a target for antivirals.


Subject(s)
Betacoronavirus/metabolism , Bismuth/pharmacology , Methyltransferases/metabolism , Nucleoside-Triphosphatase/drug effects , RNA Helicases/drug effects , Salts/pharmacology , Viral Nonstructural Proteins/metabolism , Adenosine Triphosphatases/drug effects , Adenosine Triphosphatases/metabolism , Betacoronavirus/enzymology , Betacoronavirus/genetics , COVID-19 , Coronavirus Infections/virology , Humans , Methyltransferases/genetics , Nucleoside-Triphosphatase/genetics , Nucleoside-Triphosphatase/metabolism , Pandemics , Pneumonia, Viral/virology , RNA Helicases/genetics , RNA Helicases/metabolism , Recombinant Proteins , SARS-CoV-2 , Severe Acute Respiratory Syndrome , Viral Nonstructural Proteins/genetics , Virus Replication
9.
Immunity ; 53(5): 1108-1122.e5, 2020 11 17.
Article in English | MEDLINE | ID: covidwho-880509

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic is a global public health crisis. However, little is known about the pathogenesis and biomarkers of COVID-19. Here, we profiled host responses to COVID-19 by performing plasma proteomics of a cohort of COVID-19 patients, including non-survivors and survivors recovered from mild or severe symptoms, and uncovered numerous COVID-19-associated alterations of plasma proteins. We developed a machine-learning-based pipeline to identify 11 proteins as biomarkers and a set of biomarker combinations, which were validated by an independent cohort and accurately distinguished and predicted COVID-19 outcomes. Some of the biomarkers were further validated by enzyme-linked immunosorbent assay (ELISA) using a larger cohort. These markedly altered proteins, including the biomarkers, mediate pathophysiological pathways, such as immune or inflammatory responses, platelet degranulation and coagulation, and metabolism, that likely contribute to the pathogenesis. Our findings provide valuable knowledge about COVID-19 biomarkers and shed light on the pathogenesis and potential therapeutic targets of COVID-19.


Subject(s)
Coronavirus Infections/blood , Coronavirus Infections/pathology , Plasma/metabolism , Pneumonia, Viral/blood , Pneumonia, Viral/pathology , Adult , Aged , Aged, 80 and over , Betacoronavirus , Biomarkers/blood , Blood Proteins/metabolism , COVID-19 , Coronavirus Infections/classification , Coronavirus Infections/metabolism , Female , Humans , Machine Learning , Male , Middle Aged , Pandemics/classification , Pneumonia, Viral/classification , Pneumonia, Viral/metabolism , Proteomics , Reproducibility of Results , SARS-CoV-2
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