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1.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-314470

ABSTRACT

Background: The ongoing pandemic of COVID‐19 has led to an unprecedented global crisis with problems of fragmentation in healthcare services in many severely affected countries. A key issue is distinguishing the clinical manifestations of COVID-19 from other respiratory infectious disease, especially in children and teens. Methods: : To provide precise and comprehensive information on SARS-CoV-2 infected children, a total 62 hospitalized patients, aged from 1 to 14 years old and confirmed with the infection of either SARS-CoV-2 or influenza A virus, were enrolled from September 2019 to February 2020. The epidemiological, clinical and laboratory characteristics, as well as the outcomes of these pediatric patients were collected, followed by comparisons and regression analysis on clinical features and hematological parameters among the COVID-19 patients and the flu patients. Results: : We reported that SARS-CoV-2 infected children showed less fever (43.33% vs 100%, p<0.001) with mild elevation of the body temperature (p<0.001), as well as attenuated inflammatory responses in comparison with patients with influenza A infection. We further showed the significant correlations between initial body temperature and multiple immune parameters (white blood cell counts and inflammatory markers) among SARS-CoV-2 infected children. Conclusions: : Children with SARS-CoV-2 infection were more likely to have mild symptoms and relatively slow progression with a hypo-inflammatory response. Furthermore, the correlation results suggested that distinct immune responses were involved during SARS-CoV-2 infection.

2.
Nat Microbiol ; 7(3): 423-433, 2022 03.
Article in English | MEDLINE | ID: covidwho-1671570

ABSTRACT

Elucidating the dynamics of the neutralizing antibody (nAb) response in coronavirus disease 2019 (COVID-19) convalescents is crucial in controlling the pandemic and informing vaccination strategies. Here we measured nAb titres across 411 sequential plasma samples collected during 1-480 d after illness onset or laboratory confirmation (d.a.o.) from 214 COVID-19 convalescents, covering the clinical spectrum of disease and without additional exposure history after recovery or vaccination against SARS-CoV-2, using authentic SARS-CoV-2 microneutralization (MN) assays. Forty-eight samples were also tested for neutralizing activities against the circulating variants using pseudotyped neutralization assay. Results showed that anti-RBD IgG and MN titres peaked at ~120 d.a.o. and subsequently declined, with significantly reduced nAb responses found in 91.67% of COVID-19 convalescents (≥50% decrease in current MN titres compared with the paired peak MN titres). Despite this decline, majority of the COVID-19 convalescents maintained detectable anti-RBD IgG and MN titres at 400-480 d.a.o., with undetectable neutralizing activity found in 14.41% (16/111) of the mild and 50% (5/10) of the asymptomatic infections at 330-480 d.a.o. Persistent antibody-dependent immunity could provide protection against circulating variants after one year, despite significantly decreased neutralizing activities against Beta, Delta and Mu variants. In conclusion, these data show that despite a marked decline in neutralizing activity over time, nAb responses persist for up to 480 d in most convalescents of symptomatic COVID-19, whereas a high rate of undetectable nAb responses was found in convalescents from asymptomatic infections.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , SARS-CoV-2/physiology , Adolescent , Adult , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Asymptomatic Infections/epidemiology , COVID-19/blood , COVID-19/epidemiology , COVID-19/virology , Child , Child, Preschool , Cohort Studies , Female , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin M/blood , Immunoglobulin M/immunology , Male , Middle Aged , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Young Adult
5.
J Immunol ; 207(7): 1848-1856, 2021 10 01.
Article in English | MEDLINE | ID: covidwho-1377034

ABSTRACT

Immune cell responses are strikingly altered in patients with severe coronavirus disease 2019 (COVID-19), but the immunoregulatory process in these individuals is not fully understood. In this study, 23 patients with mild and 22 patients with severe COVID-19 and 6 asymptomatic carriers of COVID-19 were enrolled, along with 44 healthy controls (HC). Peripheral immune cells in HC and patients with COVID-19 were comprehensively profiled using mass cytometry. We found that in patients with severe COVID-19, the number of HLA-DRlow/- monocytes was significantly increased, but that of mucosal-associated invariant T (MAIT) cells was greatly reduced. MAIT cells were highly activated but functionally impaired in response to Escherichia coli and IL-12/IL-18 stimulation in patients with severe COVID-19, especially those with microbial coinfection. Single-cell transcriptome analysis revealed that IFN-stimulated genes were significantly upregulated in peripheral MAIT cells and monocytes from patients with severe COVID-19. IFN-α pretreatment suppressed MAIT cells' response to E. coli by triggering high levels of IL-10 production by HLA-DRlow/--suppressive monocytes. Blocking IFN-α or IL-10 receptors rescued MAIT cell function in patients with severe COVID-19. Moreover, plasma from patients with severe COVID-19 inhibited HLA-DR expression by monocytes through IL-10. These data indicate a unique pattern of immune dysregulation in severe COVID-19, which is characterized by enrichment of suppressive HLA-DRlow/- monocytes associated with functional impairment of MAIT cells through the IFN/IL-10 pathway.


Subject(s)
COVID-19/immunology , Escherichia coli Infections/immunology , Escherichia coli/physiology , Interleukin-10/metabolism , Monocytes/immunology , Mucosal-Associated Invariant T Cells/immunology , SARS-CoV-2/physiology , Adolescent , Adult , Asymptomatic Diseases , Cells, Cultured , Child , Coinfection , Disease Progression , Female , Humans , Immune Tolerance , Lymphocyte Activation , Male , Middle Aged , Severity of Illness Index , Young Adult
6.
Virol J ; 18(1): 87, 2021 04 28.
Article in English | MEDLINE | ID: covidwho-1207602

ABSTRACT

The emergence and rapid spread of the B.1.1.7 lineage (VOC-202012/01) SARS-CoV-2 variant has aroused global concern. The N501Y substitution is the only mutation in the interface between the RBD of B.1.1.7 and ACE2, raising concerns that its recognition by neutralizing antibodies may be affected. Here, we assessed the neutralizing activity and binding affinity of a panel of 12 monoclonal antibodies against the wild type and N501Y mutant SARS-CoV-2 pseudovirus and RBD protein, respectively. We found that the neutralization activity and binding affinity of most detected antibodies (10 out of 12) were unaffected, although the N501Y substitution decreased the neutralizing and binding activities of CB6 and increased that of BD-23. These findings could be of value in the development of therapeutic antibodies.


Subject(s)
Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Antibody Affinity , Binding Sites , Epitopes/immunology , HEK293 Cells , Humans , Mutation , Neutralization Tests , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics
7.
China Tropical Medicine ; 21(2):166-168, 2021.
Article in Chinese | GIM | ID: covidwho-1190668

ABSTRACT

Objective: To analyze nucleic acid detection results of coronavirus disease 2019 (COVID-19) patients' nasal swabs and sputum specimens, and we provide reference for clinical sampling methods.

8.
Innovation (N Y) ; 1(3): 100061, 2020 11 25.
Article in English | MEDLINE | ID: covidwho-1164618

ABSTRACT

The worldwide epidemic of coronavirus disease 2019 (COVID-19) is ongoing. Rapid and accurate detection of the causative virus SARS-CoV-2 is vital for the treatment and control of COVID-19. In this study, the comparative sensitivity of different respiratory specimen types were retrospectively analyzed using 3,552 clinical samples from 410 COVID-19 patients confirmed by Guangdong CDC (Center for Disease Control and Prevention). Except for bronchoalveolar lavage fluid (BALF), the sputum possessed the highest positive rate (73.4%-87.5%), followed by nasal swabs (53.1%-85.3%) for both severe and mild cases during the first 14 days after illness onset (d.a.o.). Viral RNA could be detected in all BALF samples collected from the severe group within 14 d.a.o. and lasted up to 46 d.a.o. Moreover, although viral RNA was negative in the upper respiratory samples, it was also positive in BALF samples in most cases from the severe group during treatment. Notably, no viral RNA was detected in BALF samples from the mild group. Despite typical ground-glass opacity observed via computed tomographic scans, no viral RNA was detected in the first three or all upper respiratory tract specimens from some COVID-19 patients. In conclusion, sputum is most sensitive for routine laboratory diagnosis of COVID-19, followed by nasal swabs. Detection of viral RNA in BALF improves diagnostic accuracy in severe COVID-19 patients.

10.
China Tropical Medicine ; 20(8):772-775, 2020.
Article in Chinese | GIM | ID: covidwho-860915

ABSTRACT

Objective: To analyze the clinical characteristics, cardiac injury characteristics and early warning indexes of severe type in patients with COVID-19, so as to provide data for the evaluation, clinical treatment and prognosis of COVID-19 patients.

11.
Front Immunol ; 11: 2075, 2020.
Article in English | MEDLINE | ID: covidwho-776205

ABSTRACT

To explore the metabolic changes and immune profiles in patients with COVID-19, we analyzed the data of patients with mild and severe COVID-19 as well as young children with COVID-19. Of the leukocytes, 47% (IQR, 33-59) were lymphocytes [2.5 × 109/L (IQR, 2.2-3.3)], and monocytes were 0.51 × 109/L (IQR, 0.45-0.57) in young children with COVID-19. In 32 mild COVID-19 patients, circulating monocytes were 0.45 × 109/L (IQR, 0.36-0.64). Twenty-one severe patients had low PO2 [57 mmHg (IQR, 50-73)] and SO2 [90% (IQR, 86-93)] and high lactate dehydrogenase [580 U/L (IQR, 447-696)], cardiac troponin I [0.07 ng/mL (IQR, 0.02-0.30)], and pro-BNP [498 pg/mL (IQR, 241-1,726)]. Serum D-dimer and FDP were 9.89 mg/L (IQR, 3.62-22.85) and 32.7 mg/L (IQR, 12.8-81.9), and a large number of RBC (46/µL (IQR, 4-242) was presented in urine, a cue of disseminated intravascular coagulation (DIC) in severe patients. Three patients had comorbidity with diabetes, and 18 patients without diabetes also presented high blood glucose [7.4 mmol/L (IQR, 5.9-10.1)]. Fifteen of 21 (71%) severe cases had urine glucose +, and nine of 21 (43%) had urine ketone body +. The increased glucose was partially caused by reduced glucose consumption of cells. Severe cases had extraordinarily low serum uric acid [176 µmol/L (IQR, 131-256)]. In the late stage of COVID-19, severe cases had extremely low CD4+ T cells and CD8+ T cells, but unusually high neutrophils [6.5 × 109/L (IQR, 4.8-9.6)], procalcitonin [0.27 ng/mL (IQR, 0.14-1.94)], C-reactive protein [66 mg/L (IQR, 25-114)] and an extremely high level of interleukin-6. Four of 21 (19%) severe cases had co-infection with fungi, and two of 21 (9%) severe cases had bacterial infection. Our findings suggest that, severe cases had acute respiratory distress syndrome (ARDS) I-III, and metabolic disorders of glucose, lipid, uric acid, etc., even multiple organ dysfunction (MODS) and DIC. Increased neutrophils and severe inflammatory responses were involved in ARDS, MODS, and DIC. With the dramatical decrease of T-lymphocytes, severe cases were susceptible to co-infect with bacteria and fungi in the late stage of COVID-19. In young children, extremely high lymphocytes and monocytes might be associated with the low morbidity of COVID-19. The significantly increased monocytes might play an important role in the recovery of patients with mild COVID-19.


Subject(s)
Betacoronavirus/genetics , Coronavirus Infections/immunology , Coronavirus Infections/metabolism , Pneumonia, Viral/immunology , Pneumonia, Viral/metabolism , Adult , Aged , Blood Glucose/analysis , C-Reactive Protein/analysis , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19 , Child , Child, Preschool , Coronavirus Infections/virology , Female , Humans , Interleukin-6/blood , Lymphocyte Count , Male , Middle Aged , Neutrophils/immunology , Pandemics , Pneumonia, Viral/virology , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2 , Uric Acid/blood
12.
Eur J Clin Microbiol Infect Dis ; 39(12): 2271-2277, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-652076

ABSTRACT

We developed a chemiluminescence immunoassay method based on the recombinant nucleocapsid antigen and assessed its performance for the clinical diagnosis of severe acute respiratory syndrome coronavirus (SARS-CoV)-2 infections by detecting SARS-CoV-2-specific IgM and IgG antibodies in patients. Full-length recombinant nucleocapsid antigen and tosyl magnetic beads were used to develop the chemiluminescence immunoassay approach. Plasmas from 29 healthy cohorts, 51 tuberculosis patients, and 79 confirmed SARS-CoV-2 patients were employed to evaluate the chemiluminescence immunoassay method performance for the clinical diagnosis of SARS-CoV-2 infections. A commercial ELISA kit (Darui Biotech, China) using the same nucleocapsid antigen was used for the in-parallel comparison with our chemiluminescence immunoassay method. The IgM and IgG manner of testing in the chemiluminescence immunoassay method showed a sensitivity and specificity of 60.76% (95% CI 49.1 to 71.6) and 92.25% (95% CI 83.4 to 97.2) and 82.28% (95% CI 72.1 to 90.0) and 97.5% (95% CI 91.3 to 99.7), respectively. Higher sensitivity and specificity were observed in the chemiluminescence immunoassay method compared with the Darui Biotech ELISA kit. The developed high sensitivity and specificity chemiluminescence immunoassay IgG testing method combined with the RT-PCR approach can improve the clinical diagnosis for SARS-CoV-2 infections and thus contribute to the control of COVID-19 expansion.


Subject(s)
Antibodies, Viral/blood , Betacoronavirus/immunology , Clinical Laboratory Techniques/methods , Coronavirus Infections/diagnosis , Luminescent Measurements/methods , Nucleocapsid Proteins/blood , Pandemics , Pneumonia, Viral/diagnosis , Adolescent , Adult , Aged , Betacoronavirus/pathogenicity , COVID-19 , COVID-19 Testing , Case-Control Studies , China/epidemiology , Coronavirus Infections/blood , Coronavirus Infections/epidemiology , Coronavirus Infections/immunology , Coronavirus Nucleocapsid Proteins , False Positive Reactions , Female , Humans , Immunoassay/methods , Immunoglobulin G/blood , Immunoglobulin M/blood , Male , Middle Aged , Phosphoproteins , Pneumonia, Viral/blood , Pneumonia, Viral/epidemiology , Pneumonia, Viral/immunology , SARS-CoV-2 , Sensitivity and Specificity , Severity of Illness Index
13.
J Allergy Clin Immunol ; 146(1): 119-127.e4, 2020 Jul.
Article in English | MEDLINE | ID: covidwho-170708

ABSTRACT

BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 was first reported in Wuhan, December 2019, and continuously poses a serious threat to public health, highlighting the urgent need of identifying biomarkers for disease severity and progression. OBJECTIVE: We sought to identify biomarkers for disease severity and progression of COVID-19. METHODS: Forty-eight cytokines in the plasma samples from 50 COVID-19 cases including 11 critically ill, 25 severe, and 14 moderate patients were measured and analyzed in combination with clinical data. RESULTS: Levels of 14 cytokines were found to be significantly elevated in COVID-19 cases and showed different expression profiles in patients with different disease severity. Moreover, expression levels of IFN-γ-induced protein 10, monocyte chemotactic protein-3, hepatocyte growth factor, monokine-induced gamma IFN, and macrophage inflammatory protein 1 alpha, which were shown to be highly associated with disease severity during disease progression, were remarkably higher in critically ill patients, followed by severe and then the moderate patients. Serial detection of the 5 cytokines in 16 cases showed that continuously high levels were associated with deteriorated progression of disease and fatal outcome. Furthermore, IFN-γ-induced protein 10 and monocyte chemotactic protein-3 were excellent predictors for the progression of COVID-19, and the combination of the 2 cytokines showed the biggest area under the curve of the receiver-operating characteristics calculations with a value of 0.99. CONCLUSIONS: In this study, we report biomarkers that are highly associated with disease severity and progression of COVID-19. These findings add to our understanding of the immunopathologic mechanisms of severe acute respiratory syndrome coronavirus 2 infection, and provide potential therapeutic targets and strategies.


Subject(s)
Biomarkers/blood , Chemokine CCL7/blood , Chemokine CXCL10/blood , Coronavirus Infections/blood , Pneumonia, Viral/blood , Adult , Aged , Betacoronavirus , COVID-19 , Critical Illness , Cytokines/blood , Disease Progression , Female , Humans , Male , Middle Aged , Pandemics , SARS-CoV-2 , Young Adult
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