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1.
Nature ; 600(7888): 295-301, 2021 12.
Article in English | MEDLINE | ID: covidwho-1626235

ABSTRACT

SARS-CoV-2 is a single-stranded RNA virus that causes COVID-19. Given its acute and often self-limiting course, it is likely that components of the innate immune system play a central part in controlling virus replication and determining clinical outcome. Natural killer (NK) cells are innate lymphocytes with notable activity against a broad range of viruses, including RNA viruses1,2. NK cell function may be altered during COVID-19 despite increased representation of NK cells with an activated and adaptive phenotype3,4. Here we show that a decline in viral load in COVID-19 correlates with NK cell status and that NK cells can control SARS-CoV-2 replication by recognizing infected target cells. In severe COVID-19, NK cells show defects in virus control, cytokine production and cell-mediated cytotoxicity despite high expression of cytotoxic effector molecules. Single-cell RNA sequencing of NK cells over the time course of the COVID-19 disease spectrum reveals a distinct gene expression signature. Transcriptional networks of interferon-driven NK cell activation are superimposed by a dominant transforming growth factor-ß (TGFß) response signature, with reduced expression of genes related to cell-cell adhesion, granule exocytosis and cell-mediated cytotoxicity. In severe COVID-19, serum levels of TGFß peak during the first two weeks of infection, and serum obtained from these patients severely inhibits NK cell function in a TGFß-dependent manner. Our data reveal that an untimely production of TGFß is a hallmark of severe COVID-19 and may inhibit NK cell function and early control of the virus.


Subject(s)
COVID-19/immunology , Killer Cells, Natural/immunology , SARS-CoV-2/immunology , Transforming Growth Factor beta/immunology , Atlases as Topic , Gene Expression Regulation/immunology , Humans , Immunity, Innate , Influenza, Human/immunology , Killer Cells, Natural/pathology , RNA-Seq , Single-Cell Analysis , Time Factors , Transforming Growth Factor beta/blood , Viral Load/immunology , Virus Replication/immunology
2.
Nature ; 600(7888): 295-301, 2021 12.
Article in English | MEDLINE | ID: covidwho-1483137

ABSTRACT

SARS-CoV-2 is a single-stranded RNA virus that causes COVID-19. Given its acute and often self-limiting course, it is likely that components of the innate immune system play a central part in controlling virus replication and determining clinical outcome. Natural killer (NK) cells are innate lymphocytes with notable activity against a broad range of viruses, including RNA viruses1,2. NK cell function may be altered during COVID-19 despite increased representation of NK cells with an activated and adaptive phenotype3,4. Here we show that a decline in viral load in COVID-19 correlates with NK cell status and that NK cells can control SARS-CoV-2 replication by recognizing infected target cells. In severe COVID-19, NK cells show defects in virus control, cytokine production and cell-mediated cytotoxicity despite high expression of cytotoxic effector molecules. Single-cell RNA sequencing of NK cells over the time course of the COVID-19 disease spectrum reveals a distinct gene expression signature. Transcriptional networks of interferon-driven NK cell activation are superimposed by a dominant transforming growth factor-ß (TGFß) response signature, with reduced expression of genes related to cell-cell adhesion, granule exocytosis and cell-mediated cytotoxicity. In severe COVID-19, serum levels of TGFß peak during the first two weeks of infection, and serum obtained from these patients severely inhibits NK cell function in a TGFß-dependent manner. Our data reveal that an untimely production of TGFß is a hallmark of severe COVID-19 and may inhibit NK cell function and early control of the virus.


Subject(s)
COVID-19/immunology , Killer Cells, Natural/immunology , SARS-CoV-2/immunology , Transforming Growth Factor beta/immunology , Atlases as Topic , Gene Expression Regulation/immunology , Humans , Immunity, Innate , Influenza, Human/immunology , Killer Cells, Natural/pathology , RNA-Seq , Single-Cell Analysis , Time Factors , Transforming Growth Factor beta/blood , Viral Load/immunology , Virus Replication/immunology
3.
Mucosal Immunol ; 14(6): 1381-1392, 2021 11.
Article in English | MEDLINE | ID: covidwho-1366810

ABSTRACT

The SARS-CoV-2 pandemic has so far claimed over three and a half million lives worldwide. Though the SARS-CoV-2 mediated disease COVID-19 has first been characterized by an infection of the upper airways and the lung, recent evidence suggests a complex disease including gastrointestinal symptoms. Even if a direct viral tropism of intestinal cells has recently been demonstrated, it remains unclear, whether gastrointestinal symptoms are caused by direct infection of the gastrointestinal tract by SARS-CoV-2 or whether they are a consequence of a systemic immune activation and subsequent modulation of the mucosal immune system. To better understand the cause of intestinal symptoms we analyzed biopsies of the small intestine from SARS-CoV-2 infected individuals. Applying qRT-PCR and immunohistochemistry, we detected SARS-CoV-2 RNA and nucleocapsid protein in duodenal mucosa. In addition, applying imaging mass cytometry and immunohistochemistry, we identified histomorphological changes of the epithelium, which were characterized by an accumulation of activated intraepithelial CD8+ T cells as well as epithelial apoptosis and subsequent regenerative proliferation in the small intestine of COVID-19 patients. In summary, our findings indicate that intraepithelial CD8+ T cells are activated upon infection of intestinal epithelial cells with SARS-CoV-2, providing one possible explanation for gastrointestinal symptoms associated with COVID-19.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , Duodenum/immunology , Immunity, Mucosal , Intestinal Diseases/immunology , Intestinal Mucosa/immunology , Intraepithelial Lymphocytes/immunology , Lymphocyte Activation , SARS-CoV-2/immunology , Adult , Aged , Animals , Apoptosis , CD8-Positive T-Lymphocytes/virology , COVID-19/pathology , COVID-19/virology , Case-Control Studies , Cell Proliferation , Chlorocebus aethiops , Duodenum/pathology , Duodenum/virology , Female , Host-Pathogen Interactions , Humans , Intestinal Diseases/pathology , Intestinal Diseases/virology , Intestinal Mucosa/pathology , Intestinal Mucosa/virology , Intraepithelial Lymphocytes/virology , Male , Re-Epithelialization , SARS-CoV-2/pathogenicity , Vero Cells , Viral Load
4.
Kidney Int Rep ; 6(4): 905-915, 2021 Apr.
Article in English | MEDLINE | ID: covidwho-1169160

ABSTRACT

INTRODUCTION: Acute kidney injury (AKI) is an important complication in COVID-19, but its precise etiology has not fully been elucidated. Insights into AKI mechanisms may be provided by analyzing the temporal associations of clinical parameters reflecting disease processes and AKI development. METHODS: We performed an observational cohort study of 223 consecutive COVID-19 patients treated at 3 sites of a tertiary care referral center to describe the evolvement of severe AKI (Kidney Disease: Improving Global Outcomes stage 3) and identify conditions promoting its development. Descriptive statistics and explanatory multivariable Cox regression modeling with clinical parameters as time-varying covariates were used to identify risk factors of severe AKI. RESULTS: Severe AKI developed in 70 of 223 patients (31%) with COVID-19, of which 95.7% required kidney replacement therapy. Patients with severe AKI were older, predominantly male, had more comorbidities, and displayed excess mortality. Severe AKI occurred exclusively in intensive care unit patients, and 97.3% of the patients developing severe AKI had respiratory failure. Mechanical ventilation, vasopressor therapy, and inflammatory markers (serum procalcitonin levels and leucocyte count) were independent time-varying risk factors of severe AKI. Increasing inflammatory markers displayed a close temporal association with the development of severe AKI. Sensitivity analysis on risk factors of AKI stage 2 and 3 combined confirmed these findings. CONCLUSION: Severe AKI in COVID-19 was tightly coupled with critical illness and systemic inflammation and was not observed in milder disease courses. These findings suggest that traditional systemic AKI mechanisms rather than kidney-specific processes contribute to severe AKI in COVID-19.

5.
Cancer Med ; 9(22): 8571-8578, 2020 11.
Article in English | MEDLINE | ID: covidwho-777421

ABSTRACT

BACKGROUND: Patients with malignancy are particularly vulnerable to infection with Severe Acute Respiratory Disease-Coronavirus-2 (SARS-CoV-2) given their immunodeficiency secondary to their underlying disease and cancer-directed therapy. We report a case series of patients with cancer who received convalescent plasma, an investigational therapy for severe Coronavirus Disease 2019 (COVID-19). METHODS: Patients with cancer were identified who received convalescent plasma. Enrolled patients had confirmed COVID-19 with severe or life-threatening disease and were transfused with convalescent plasma from donors with a SARS-CoV-2 anti-spike antibody titer of ≥ 1:320 dilution. Oxygen requirements and clinical outcomes of interests were captured as well as laboratory parameters at baseline and 3 days after treatment. RESULTS: We identified 24 patients with cancer, 14 of whom had a hematological malignancy, who were treated with convalescent plasma. Fifteen patients (62.5%) were on cancer-directed treatment at the time of COVID-19 infection. After a median of hospital duration of 9 days, 13 patients (54.2%) had been discharged home, 1 patient (4.2%) was still hospitalized, and 10 patients had died (41.7%). Non-intubated patients, particularly those on nasal cannula alone, had favorable outcomes. Three mild febrile non-hemolytic transfusion reactions were observed. C-reactive protein significantly decreased after 3 days of treatment, while other laboratory parameters including ferritin and D-dimer remained unchanged. CONCLUSIONS: Convalescent plasma may be a promising therapy in cancer patients with COVID-19.


Subject(s)
Betacoronavirus/isolation & purification , Coronavirus Infections/complications , Hospitalization/statistics & numerical data , Neoplasms/therapy , Pneumonia, Viral/complications , Severity of Illness Index , Adult , Aged , Aged, 80 and over , COVID-19 , Coronavirus Infections/therapy , Coronavirus Infections/transmission , Coronavirus Infections/virology , Female , Humans , Immunization, Passive , Male , Middle Aged , Neoplasms/epidemiology , Neoplasms/virology , Pandemics , Pneumonia, Viral/therapy , Pneumonia, Viral/transmission , Pneumonia, Viral/virology , Prognosis , Risk Factors , SARS-CoV-2 , Survival Rate , United States/epidemiology
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