| Title:
|
SARS-CoV-2 drives JAK1/2-dependent local complement hyperactivation |
| Abstract:
|
Patients with coronavirus disease 2019 (COVID-19) present a wide range of acute clinical manifestations affecting the lungs liver kidneys and gut. Angiotensin converting enzyme (ACE) 2 the best-characterized entry receptor for the disease-causing virus SARS-CoV-2 is highly expressed in the aforementioned tissues. However the pathways that underlie the disease are still poorly understood. Here we unexpectedly found that the complement system was one of the intracellular pathways most highly induced by SARS-CoV-2 infection in lung epithelial cells. Infection of respiratory epithelial cells with SARS-CoV-2 generated activated complement component C3a and could be blocked by a cell-permeable inhibitor of complement factor B (CFBi) indicating the presence of an inducible cell-intrinsic C3 convertase in respiratory epithelial cells. Within cells of the bronchoalveolar lavage of patients distinct signatures of complement activation in myeloid lymphoid and epithelial cells tracked with disease severity. Genes induced by SARS-CoV-2 and the drugs that could normalize these genes both implicated the interferon-JAK1/2-STAT1 signaling system and NF-B as the main drivers of their expression. Ruxolitinib a JAK1/2 inhibitor normalized interferon signature genes and all complement gene transcripts induced by SARS-CoV-2 in lung epithelial cell lines but did not affect NF-B-regulated genes. Ruxolitinib alone or in combination with the antiviral remdesivir inhibited C3a protein produced by infected cells. Together we postulate that combination therapy with JAK inhibitors and drugs that normalize NF-B-signaling could potentially have clinical application for severe COVID-19. |
| Published:
|
2021-04-07 |
| Journal:
|
Sci Immunol |
| DOI:
|
10.1126/sciimmunol.abg0833 |
| DOI_URL:
|
http://doi.org/10.1126/sciimmunol.abg0833 |
| Author Name:
|
Yan Bingyu |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/yan_bingyu |
| Author Name:
|
Freiwald Tilo |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/freiwald_tilo |
| Author Name:
|
Chauss Daniel |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/chauss_daniel |
| Author Name:
|
Wang Luopin |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/wang_luopin |
| Author Name:
|
West Erin |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/west_erin |
| Author Name:
|
Mirabelli Carmen |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/mirabelli_carmen |
| Author Name:
|
Zhang Charles J |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/zhang_charles_j |
| Author Name:
|
Nichols Eva Maria |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/nichols_eva_maria |
| Author Name:
|
Malik Nazish |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/malik_nazish |
| Author Name:
|
Gregory Richard |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/gregory_richard |
| Author Name:
|
Bantscheff Marcus |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/bantscheff_marcus |
| Author Name:
|
Ghidelli Disse Sonja |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/ghidelli_disse_sonja |
| Author Name:
|
Kolev Martin |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/kolev_martin |
| Author Name:
|
Frum Tristan |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/frum_tristan |
| Author Name:
|
Spence Jason R |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/spence_jason_r |
| Author Name:
|
Sexton Jonathan Z |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/sexton_jonathan_z |
| Author Name:
|
Alysandratos Konstantinos D |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/alysandratos_konstantinos_d |
| Author Name:
|
Kotton Darrell N |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/kotton_darrell_n |
| Author Name:
|
Pittaluga Stefania |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/pittaluga_stefania |
| Author Name:
|
Bibby Jack |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/bibby_jack |
| Author Name:
|
Niyonzima Nathalie |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/niyonzima_nathalie |
| Author Name:
|
Olson Matthew R |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/olson_matthew_r |
| Author Name:
|
Kordasti Shahram |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/kordasti_shahram |
| Author Name:
|
Portilla Didier |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/portilla_didier |
| Author Name:
|
Wobus Christiane E |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/wobus_christiane_e |
| Author Name:
|
Laurence Arian |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/laurence_arian |
| Author Name:
|
Lionakis Michail S |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/lionakis_michail_s |
| Author Name:
|
Kemper Claudia |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/kemper_claudia |
| Author Name:
|
Afzali Behdad |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/afzali_behdad |
| Author Name:
|
Kazemian Majid |
| Author link:
|
https://covid19-data.nist.gov/pid/rest/local/author/kazemian_majid |
| sha:
|
4999d439f376bfd55abec9904e9a421e3aa4b13a |
| license:
|
cc-by |
| license_url:
|
https://creativecommons.org/licenses/by/4.0/ |
| source_x:
|
Medline; PMC |
| source_x_url:
|
https://www.medline.com/https://www.ncbi.nlm.nih.gov/pubmed/ |
| pubmed_id:
|
33827897 |
| pubmed_id_url:
|
https://www.ncbi.nlm.nih.gov/pubmed/33827897 |
| pmcid:
|
PMC8139422 |
| pmcid_url:
|
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8139422 |
| url:
|
https://www.ncbi.nlm.nih.gov/pubmed/33827897/
https://doi.org/10.1126/sciimmunol.abg0833 |
| has_full_text:
|
TRUE |
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| Extracted Text Content in Record:
|
First 5000 Characters:Coronavirus disease 2019 (COVID)-19, a viral pneumonia caused by a beta coronavirus named severe acute respiratory syndrome coronavirus (SARS-CoV)-2, is now a pandemic. Patients with COVID-19 present variable clinical symptoms, ranging from a mild upper respiratory tract illness to a CORONAVIRUS SARS-CoV-2 drives JAK1/2-dependent local complement hyperactivation significant disease with severe and life-threatening complications, characterized by combinations of acute respiratory distress syndrome, coagulopathy, vasculitis, kidney, liver and gastrointestinal injury (1) . Survivors, and those with milder presentations, may suffer from loss of normal tissue function due to persistent inflammation and/or fibrosis. (2, 3) . The pathogenesis of COVID-19 and the causes of its variable severity are poorly understood, thus a better mechanistic understanding of the disease will help identify at-risk patients and allow for the development and refinement of muchneeded treatments.
The complement system is an evolutionarily conserved component of innate immunity, required for pathogen recognition and removal (4) . The key components are complement (C)3 and C5, which circulate in their pro-enzyme forms in blood and interstitial fluids. C3 is activated through the classical (antibody signal), lectin (pattern recognition signal) and/or alternative (altered-self and tick-over) pathways into bio-active C3a and C3b via cleavage by an enzyme complex called C3 convertase. Complement factor B (CFB) is a key component of the alternative pathway C3 convertase. C3b generation triggers subsequent activation of C5 into C5a and C5b, with the latter seeding the formation of the lytic membrane attack complex (MAC) on pathogens or target cells. C3a and C5a are anaphylatoxins and induce a general inflammatory reaction by binding to their respective receptors, C3a receptor (C3aR) and C5aR1 expressed on immune cell. C3b binds its canonical receptor, CD46, which is expressed on nucleated cells and acts as both a complement regulator and a driver of T helper 1 differentiation in CD4 + T cells (5, 6) . Although the traditional view of complement is as a hepatocytederived and serum-effective system, the complement system is also expressed and biologically active within cells (7) .
Patients with severe COVID-19 have high circulating levels of terminal activation fragments of complement (C5a and sC5b-9) (8) (9) (10) , which correlate to disease severity (8) . Single nucleotide variants in two complement regulators, decay accelerating factor (CD55) and complement factor H, are risk factors for morbidity and mortality from SARS-CoV-2 (11) . This is concordant with a recent report, which shows that serum C3 hyperactivation is an independent risk factor for inhospital mortality (12) . Despite these reports, the mechanisms behind the overactivation and conversion of the normally protective complement system into a harmful component of COVID-19 are currently unclear.
Here, we examined the transcriptomes of respiratory epithelial cells infected with SARS-CoV-2 and found that the complement system was one of the intracellular pathways most highly induced in response to infection. C3 protein was processed to active fragments by expression of an inducible alternative pathway convertase (CFB) and that was normalized by a cell-permeable inhibitor of CFB. Interferon signaling via the JAK1/2-STAT1 pathway was principally responsible for transcription of complement genes in this setting and ruxolitinib, a JAK1 inhibitor, alone or in combination with remdesivir, an anti-viral agent, normalized this transcriptional response and production of processed C3 fragments from infected cells.
To gain insights into the pathophysiologic mechanisms of COVID-19, we sourced bulk RNA-seq data from lung tissues of two patients with SARS-CoV-2 infection and uninfected controls (Table S1A) (13) . We compared the transcriptomes of patients to controls using gene set enrichment analysis (GSEA) (14) and found 36 canonical pathways curated by the Molecular Signatures Database (MSigDB) to be induced in patients compared to controls ( Fig. 1A and Table S1B ). Five of the 36 (14%) enriched pathways were annotated as complement pathways. Traditionally, complement is considered a mostly hepatocyte-derived and serum-effective system (4) . Thus, the dominance of the SARS-CoV-2-induced lung cellintrinsic complement signature was unexpected.
Since the patient lung biopsy samples contained a mixed population of lung cells, we next defined the cellular source of the complement signature in the affected lungs. To this end, we examined the transcriptomes of primary human bronchial epithelial (NHBE) cells infected in vitro with SARS-CoV-2, which again identified several complement pathways as highly enriched in infected cells. In fact, hierarchical classification of enriched pathways by significance (FDR q-value) showed that complement pathways were among the most highly enriched of all pathways fo |
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| Extracted PMC Text Content in Record:
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First 5000 Characters:Coronavirus disease 2019 (COVID)-19, a viral pneumonia caused by a beta coronavirus named severe acute respiratory syndrome coronavirus (SARS-CoV)-2, is now a pandemic. Patients with COVID-19 present variable clinical symptoms, ranging from a mild upper respiratory tract illness to a significant disease with severe and life-threatening complications, characterized by combinations of acute respiratory distress syndrome, coagulopathy, vasculitis, kidney, liver and gastrointestinal injury (1). Survivors, and those with milder presentations, may suffer from loss of normal tissue function due to persistent inflammation and/or fibrosis. (2, 3). The pathogenesis of COVID-19 and the causes of its variable severity are poorly understood, thus a better mechanistic understanding of the disease will help identify at-risk patients and allow for the development and refinement of much-needed treatments.
The complement system is an evolutionarily conserved component of innate immunity, required for pathogen recognition and removal (4). The key components are complement (C)3 and C5, which circulate in their pro-enzyme forms in blood and interstitial fluids. C3 is activated through the classical (antibody signal), lectin (pattern recognition signal) and/or alternative (altered-self and tick-over) pathways into bio-active C3a and C3b via cleavage by an enzyme complex called C3 convertase. Complement factor B (CFB) is a key component of the alternative pathway C3 convertase. C3b generation triggers subsequent activation of C5 into C5a and C5b, with the latter seeding the formation of the lytic membrane attack complex (MAC) on pathogens or target cells. C3a and C5a are anaphylatoxins and induce a general inflammatory reaction by binding to their respective receptors, C3a receptor (C3aR) and C5aR1 expressed on immune cell. C3b binds its canonical receptor, CD46, which is expressed on nucleated cells and acts as both a complement regulator and a driver of T helper 1 differentiation in CD4+ T cells (5, 6). Although the traditional view of complement is as a hepatocyte-derived and serum-effective system, the complement system is also expressed and biologically active within cells (7).
Patients with severe COVID-19 have high circulating levels of terminal activation fragments of complement (C5a and sC5b-9) (810), which correlate to disease severity (8). Single nucleotide variants in two complement regulators, decay accelerating factor (CD55) and complement factor H, are risk factors for morbidity and mortality from SARS-CoV-2 (11). This is concordant with a recent report, which shows that serum C3 hyperactivation is an independent risk factor for in-hospital mortality (12). Despite these reports, the mechanisms behind the overactivation and conversion of the normally protective complement system into a harmful component of COVID-19 are currently unclear.
Here, we examined the transcriptomes of respiratory epithelial cells infected with SARS-CoV-2 and found that the complement system was one of the intracellular pathways most highly induced in response to infection. C3 protein was processed to active fragments by expression of an inducible alternative pathway convertase (CFB) and that was normalized by a cell-permeable inhibitor of CFB. Interferon signaling via the JAK1/2STAT1 pathway was principally responsible for transcription of complement genes in this setting and ruxolitinib, a JAK1 inhibitor, alone or in combination with remdesivir, an anti-viral agent, normalized this transcriptional response and production of processed C3 fragments from infected cells.
To gain insights into the pathophysiologic mechanisms of COVID-19, we sourced bulk RNA-seq data from lung tissues of two patients with SARS-CoV-2 infection and uninfected controls (Table S1A) (13). We compared the transcriptomes of patients to controls using gene set enrichment analysis (GSEA) (14) and found 36 canonical pathways curated by the Molecular Signatures Database (MSigDB) to be induced in patients compared to controls (Fig. 1A and Table S1B). Five of the 36 (14%) enriched pathways were annotated as complement pathways. Traditionally, complement is considered a mostly hepatocyte-derived and serum-effective system (4). Thus, the dominance of the SARS-CoV-2-induced lung cell-intrinsic complement signature was unexpected.
Since the patient lung biopsy samples contained a mixed population of lung cells, we next defined the cellular source of the complement signature in the affected lungs. To this end, we examined the transcriptomes of primary human bronchial epithelial (NHBE) cells infected in vitro with SARS-CoV-2, which again identified several complement pathways as highly enriched in infected cells. In fact, hierarchical classification of enriched pathways by significance (FDR q-value) showed that complement pathways were among the most highly enriched of all pathways following SARS-CoV-2 infection (Fig. 1B). One of the cell types infected by SARS-CoV-2 are type II p |
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sars_cov_2_drives_jak1_2_dependent_local_complement_hyperactivation |
