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J Virol ; 96(17): e0096722, 2022 09 14.
Article in English | MEDLINE | ID: covidwho-1986331


Host factors play critical roles in SARS-CoV-2 infection-associated pathology and the severity of COVID-19. In this study, we systematically analyzed the roles of SARS-CoV-2-induced host factors, doublecortin-like kinase 1 (DCLK1), and S100A9 in viral pathogenesis. In autopsied subjects with COVID-19 and pre-existing chronic liver disease, we observed high levels of DCLK1 and S100A9 expression and immunosuppressive (DCLK1+S100A9+CD206+) M2-like macrophages and N2-like neutrophils in lungs and livers. DCLK1 and S100A9 expression were rarely observed in normal controls, COVID-19-negative subjects with chronic lung disease, or COVID-19 subjects without chronic liver disease. In hospitalized patients with COVID-19, we detected 2 to 3-fold increased levels of circulating DCLK1+S100A9+ mononuclear cells that correlated with disease severity. We validated the SARS-CoV-2-dependent generation of these double-positive immune cells in coculture. SARS-CoV-2-induced DCLK1 expression correlated with the activation of ß-catenin, a known regulator of the DCLK1 promoter. Gain and loss of function studies showed that DCLK1 kinase amplified live virus production and promoted cytokine, chemokine, and growth factor secretion by peripheral blood mononuclear cells. Inhibition of DCLK1 kinase blocked pro-inflammatory caspase-1/interleukin-1ß signaling in infected cells. Treatment of SARS-CoV-2-infected cells with inhibitors of DCLK1 kinase and S100A9 normalized cytokine/chemokine profiles and attenuated DCLK1 expression and ß-catenin activation. In conclusion, we report previously unidentified roles of DCLK1 in augmenting SARS-CoV-2 viremia, inflammatory cytokine expression, and dysregulation of immune cells involved in innate immunity. DCLK1 could be a potential therapeutic target for COVID-19, especially in patients with underlying comorbid diseases associated with DCLK1 expression. IMPORTANCE High mortality in COVID-19 is associated with underlying comorbidities such as chronic liver diseases. Successful treatment of severe/critical COVID-19 remains challenging. Herein, we report a targetable host factor, DCLK1, that amplifies SARS-CoV-2 production, cytokine secretion, and inflammatory pathways via activation of ß-catenin(p65)/DCLK1/S100A9/NF-κB signaling. Furthermore, we observed in the lung, liver, and blood an increased prevalence of immune cells coexpressing DCLK1 and S100A9, a myeloid-derived proinflammatory protein. These cells were associated with increased disease severity in COVID-19 patients. Finally, we used a novel small-molecule inhibitor of DCLK1 kinase (DCLK1-IN-1) and S100A9 inhibitor (tasquinimod) to decrease virus production in vitro and normalize hyperinflammatory responses known to contribute to disease severity in COVID-19.

COVID-19 , Doublecortin-Like Kinases , COVID-19/metabolism , COVID-19/pathology , Calgranulin B/metabolism , Chemokines/metabolism , Cytokines/metabolism , Doublecortin-Like Kinases/antagonists & inhibitors , Doublecortin-Like Kinases/metabolism , Humans , Intracellular Signaling Peptides and Proteins/genetics , Leukocytes, Mononuclear/metabolism , Quinolones/pharmacology , SARS-CoV-2 , beta Catenin/metabolism
Viruses ; 13(8)2021 08 12.
Article in English | MEDLINE | ID: covidwho-1355052


Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19), a global pandemic characterized by an exaggerated immune response and respiratory illness. Age (>60 years) is a significant risk factor for developing severe COVID-19. To better understand the host response of the aged airway epithelium to SARS-CoV-2 infection, we performed an in vitro study using primary human bronchial epithelial cells from donors >67 years of age differentiated on an air-liquid interface culture. We demonstrate that SARS-CoV-2 infection leads to early induction of a proinflammatory response and a delayed interferon response. In addition, we observed changes in the genes and pathways associated with cell death and senescence throughout infection. In summary, our study provides new and important insights into the temporal kinetics of the airway epithelial innate immune response to SARS-CoV-2 in older individuals.

Bronchi/immunology , Bronchi/virology , Immunity, Innate , Respiratory Mucosa/immunology , Respiratory Mucosa/virology , SARS-CoV-2/immunology , Aged , Aging/immunology , Bronchi/cytology , Bronchi/metabolism , COVID-19/immunology , Cell Death/genetics , Cells, Cultured , Cellular Senescence/genetics , Cytokines/biosynthesis , Cytokines/genetics , Epithelial Cells/immunology , Epithelial Cells/metabolism , Epithelial Cells/virology , Female , Humans , Inflammation , Interferons/biosynthesis , Interferons/genetics , Male , RNA-Seq , Respiratory Mucosa/cytology , Respiratory Mucosa/metabolism , SARS-CoV-2/physiology , Signal Transduction/genetics
JCI Insight ; 6(14)2021 07 22.
Article in English | MEDLINE | ID: covidwho-1320462


Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a pandemic. Severe disease is associated with dysfunction of multiple organs, but some infected cells do not express ACE2, the canonical entry receptor for SARS-CoV-2. Here, we report that the C-type lectin receptor L-SIGN interacted in a Ca2+-dependent manner with high-mannose-type N-glycans on the SARS-CoV-2 spike protein. We found that L-SIGN was highly expressed on human liver sinusoidal endothelial cells (LSECs) and lymph node lymphatic endothelial cells but not on blood endothelial cells. Using high-resolution confocal microscopy imaging, we detected SARS-CoV-2 viral proteins within the LSECs from liver autopsy samples from patients with COVID-19. We found that both pseudo-typed virus enveloped with SARS-CoV-2 spike protein and authentic SARS-CoV-2 virus infected L-SIGN-expressing cells relative to control cells. Moreover, blocking L-SIGN function reduced CoV-2-type infection. These results indicate that L-SIGN is a receptor for SARS-CoV-2 infection. LSECs are major sources of the clotting factors vWF and factor VIII (FVIII). LSECs from liver autopsy samples from patients with COVID-19 expressed substantially higher levels of vWF and FVIII than LSECs from uninfected liver samples. Our data demonstrate that L-SIGN is an endothelial cell receptor for SARS-CoV-2 that may contribute to COVID-19-associated coagulopathy.

COVID-19 , Capillaries , Cell Adhesion Molecules/metabolism , Endothelial Cells , Lectins, C-Type/metabolism , Liver/blood supply , Lymphatic Vessels , Receptors, Cell Surface/metabolism , SARS-CoV-2/physiology , COVID-19/metabolism , COVID-19/pathology , COVID-19/virology , Capillaries/metabolism , Capillaries/pathology , Capillaries/virology , Endothelial Cells/metabolism , Endothelial Cells/pathology , Endothelial Cells/virology , Gene Expression Profiling/methods , Humans , Liver/pathology , Lymphatic Vessels/metabolism , Lymphatic Vessels/pathology , Lymphatic Vessels/virology , Spike Glycoprotein, Coronavirus , Virus Internalization