Airways tissue expression of type I interferons and their stimulated genes is higher in children than adults.

There is emerging evidence that age-dependent differences in susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) correlate with stronger innate immune response in the upper respiratory tract in children compared to adults. The efficient induction of interferon (IFN) alpha and beta (α and ß) signaling, and interferon-stimulated genes (ISGs) is fundamental to the host antiviral response. In-silico transcriptomic analyses was conducted to determine the expression levels of IFN α/ß pathway genes as well as 524 human ISGs in upper and lower airways of children and adults at baseline and post respiratory infections including coronavirus disease 2019 (COVID-19). To validate our in-silico analysis, we conducted qRT-PCR to measure ISGs levels in children and adult's nasal epithelial samples. At baseline, children had significantly higher levels of IFN α/ß and ISGs genes compared to adults. More distinction was also seen in bronchial compared to nasal basal levels. Children nasal epithelial cells exhibited superior antiviral IFN α/ß and associated ISGs response following ex-vivo poly (I:C) treatment model, and in clinical samples of SARS-CoV-2 infected patients. This was also confirmed in nasal epithelial samples using qRT-PCR validation. No gender-based difference in type I IFN levels across both age groups were observed. Understanding the biological basis for children resistance against severe COVID-19 is a challenge that has substantial clinical importance. More mechanistic studies are needed to carefully quantify how much of early IFN levels is needed to bypass the viral evasion mechanism and prevent its further replication and dissemination to lower airways and the rest of the body.

Vitamin D enhances type I IFN signaling in COVID-19 patients.

The ability of Vitamin D (VitD) to modulate antiviral responses through induction of antimicrobial peptide is well established. However, the effect of VitD on host responses to SARS-CoV-2 is not well investigated. We here report the ability of VitD to enhance host IFN-alpha/beta (a/ß) signaling both in vitro and among severe COVID-19 patients treated with VitD. Blood and saliva specimens were obtained from severe COVID-19 patients treated (43 patients), or not (37 patients), with vitD, during their stay in intensive care unit. Patients were followed up to 29 days following admission, and patient survival outcomes were collected. Higher activity levels of RIG-1/MDA-5 and JAK-STAT signaling pathways were observed with significantly higher gene and protein levels of antiviral interferon stimulating genes (ISGs) such as MX-1 and ISG-15; both in vitro, following treatment of PBMCs with vitD, and in whole blood and saliva specimens of VitD treated patients. Moreover, VitD treated patients had lower risk of all-cause mortality by day 29 compared to untreated patients (adjusted hazard ratio, 0.37, 95% confidence interval of 0.14-0.94; P = 0.038). The herein uncovered regulatory role of VitD on type I IFNs suggests the importance of insuring a normal level of VitD for the prevention and probably treatment of SARS-CoV-2 infection. Additional mechanistic studies, however, are needed to fully elucidate the antiviral effects of VitD particularly in the setting of COVID-19 infection.

Saliva metabolomic profile of COVID-19 patients associates with disease severity.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is strongly linked to dysregulation of various molecular, cellular, and physiological processes that change abundance of different biomolecules including metabolites that may be ultimately used as biomarkers for disease progression and severity. It is important at early stage to readily distinguish those patients that are likely to progress to moderate and severe stages. OBJECTIVES: This study aimed to investigate the utility of saliva and plasma metabolomic profiles as a potential parameter for risk stratifying COVID-19 patients. METHOD: LC-MS/MS-based untargeted metabolomics were used to profile the changes in saliva and plasma metabolomic profiles of COVID-19 patients with different severities. RESULTS: Saliva and plasma metabolites were screened in 62 COVID-19 patients and 18 non-infected controls. The COVID-19 group included 16 severe, 15 moderate, 16 mild, and 15 asymptomatic cases. Thirty-six differential metabolites were detected in COVID-19 versus control comparisons. SARS-CoV-2 induced metabolic derangement differed with infection severity. The metabolic changes were identified in saliva and plasma, however, saliva showed higher intensity of metabolic changes. Levels of saliva metabolites such as sphingosine and kynurenine were significantly different between COVID-19 infected and non-infected individuals; while linoleic acid and Alpha-ketoisovaleric acid were specifically increased in severe compared to non-severe patients. As expected, the two prognostic biomarkers of C-reactive protein and D-dimer were negatively correlated with sphingosine and 5-Aminolevulinic acid, and positively correlated with L-Tryptophan and L-Kynurenine. CONCLUSION: Saliva disease-specific and severity-specific metabolite could be employed as potential COVID-19 diagnostic and prognostic biomarkers.

Upregulation of interleukin-19 in saliva of patients with COVID-19.

Cytokines are major players in orchestrating inflammation, disease pathogenesis and severity during COVID-19 disease. However, the role of IL-19 in COVID-19 pathogenesis remains elusive. Herein, through the analysis of transcriptomic datasets of SARS-CoV-2 infected lung cells, nasopharyngeal swabs, and lung autopsies of COVID-19 patients, we report that expression levels of IL-19 and its receptor, IL-20R2, were upregulated following SARS-CoV-2 infection. Of 202 adult COVID-19 patients, IL-19 protein level was significantly higher in blood and saliva of asymptomatic patients compared to healthy controls when adjusted for patients' demographics (P < 0.001). Interestingly, high saliva IL-19 level was also associated with COVID-19 severity (P < 0.0001), need for mechanical ventilation (P = 0.002), and/or death (P = 0.010) within 29 days of admission, after adjusting for patients' demographics, diabetes mellitus comorbidity, and COVID-19 serum markers of severity such as D-dimer, C-reactive protein, and ferritin. Moreover, patients who received interferon beta during their hospital stay had lower plasma IL-19 concentrations (24 pg mL-1) than those who received tocilizumab (39.2 pg mL-1) or corticosteroids (42.5 pg mL-1). Our findings indicate that high saliva IL-19 level was associated with COVID-19 infectivity and disease severity.

Sotrovimab Lowers the Risk of COVID-19 Related Hospitalization or Death in a Large Population Cohort in the United Arab Emirates.

Sotrovimab, an anti-severe acute respiratory syndrome-coronavirus 2 monoclonal antibody is being utilized to prevent progression of coronavirus disease 2019 (COVID-19). Therefore, to understand its benefits, we have conducted a retrospective analysis of all non-hospitalized patients with symptomatic COVID-19 who received a single infusion of sotrovimab and/or oral favipiravir at any Dubai COVID-19 related healthcare center between July 1, 2021, and October 31, 2021. The main outcome was to evaluate the risk of hospitalization for patients with COVID-19 or all-cause death within 28 days of treatment initiation. In this analysis, which included 10,882 patients (1,135 in the sotrovimab group, 2,653 in the sotrovimab/favipiravir group, and 7,094 in the favipiravir group), sotrovimab or sotrovimab/favipiravir reduced the risk of hospitalization (13 patients (1.5%) in the sotrovimab group and 71 patients (2.9%) in the sotrovimab/favipiravir group vs. 251 patients (4%) in the favipiravir group; hazard ratio (HR) for sotrovimab: 0.16, 95% confidence interval (CI): 0.09-0.28, P < 0.001; and for sotrovimab/favipiravir, HR: 0.42, 95% CI: 0.32-0.56, P < 0.001), or death by day 28 from the start of treatment (no death in the sotrovimab group and 2 deaths in the the sotrovimab/favipiravir group vs. 10 deaths in the favipiravir group; odds ratio: 0.18, 95% CI: 0.04 to 0.81, P = 026). Safety was assessed in all the 3,788 patients in the sotrovimab and sotrovimab/favipiravir groups, and the reported adverse events were by 34 patients (<1%). In conclusion, sotrovimab was found to reduce the risk of progression of COVID-19 when administrated early to non-hospitalized patients with symptomatic COVID-19. No safety concern was detected.

Favipiravir Effectiveness and Safety in Hospitalized Moderate-Severe COVID-19 Patients: Observational Prospective Multicenter Investigation in Saudi Arabia.

Objectives: There are limited data on the efficacy and safety of favipiravir antiviral in coronavirus disease 2019 (COVID-19), particularly in the more progressed disease phase. This study aims to evaluate the favipiravir effect on reducing the length of hospital stay and in-hospital mortality among moderate and severe hospitalized COVID-19 patients. Methods: A prospective, multicenter observational study was conducted that included moderate and severe hospitalized adult COVID-19 patients in four major regions (Riyadh (Riyadh), Eastern (Dammam), Al-Qassem (Buraydah), and Macca (Jeddah) of Saudi Arabia. For the primary outcome of all-cause mortality, a Cox proportional hazard analysis was performed. While the association between favipiravir use and length of hospital stay was determined using adjusted generalized linear model. This study was approved by the Central Institutional Review Board in The Saudi Ministry of Health (MoH) with the approval number IRB # 20-85-M. Results: This study included 598 moderate and severe COVID-19 patients, of whom 156 (26%) received favipiravir. Favipiravir treatment was associated with more extended hospital stays (14 vs. 10 median days, P = 0.034) and higher mortality rate (aHR 3.63; 95% CI 1.06-12.45) compared to no favipiravir regimen. Despite lack of effectiveness, favipiravir use was only associated with higher diarrhea adverse effects (12 vs. 5%, P = 0.002), but it did not affect the renal and liver profiles of patients. Conclusion: Favipiravir was ineffective in reducing the length of hospital stay and in-hospital mortality in patients with moderate and severe COVID-19.

Asthma Associated Cytokines Regulate the Expression of SARS-CoV-2 Receptor ACE2 in the Lung Tissue of Asthmatic Patients.

It is still controversial whether chronic lung inflammation increases the risk for COVID-19. One of the risk factors for acquiring COVID-19 is the level of expression of SARS-CoV-2 entry receptors, ACE2 and TMPRSS2, in lung tissue. It is, however, not clear how lung tissue inflammation affects expression levels of these receptors. We hence aimed to determine the level of SARS-CoV-2 receptors in lung tissue of asthmatic relative to age, gender, and asthma severity, and to investigate the factors regulating that. Therefore, gene expression data sets of well-known asthmatic cohorts (SARP and U-BIOPRED) were used to evaluate the association of ACE2 and TMPRSS2 with age, gender of the asthmatic patients, and also the type of the underlying lung tissue inflammatory cytokines. Notably, ACE2 and to less extent TMPRSS2 expression were upregulated in the lung tissue of asthmatics compared to healthy controls. Although a differential expression of ACE2, but not TMPRSS2 was observed relative to age within the moderate and severe asthma groups, our data suggest that age may not be a key regulatory factor of its expression. The type of tissue inflammation, however, associated significantly with ACE2 and TMPRSS2 expression levels following adjusting with age, gender and oral corticosteroids use of the patient. Type I cytokine (IFN-γ), IL-8, and IL-19 were associated with increased expression, while Type II cytokines (IL-4 and IL-13) with lower expression of ACE2 in lung tissue (airway epithelium and/or lung biopsies) of moderate and severe asthmatic patients. Of note, IL-19 was associated with ACE2 expression while IL-17 was associated with TMPRSS2 expression in sputum of asthmatic subjects. In vitro treatment of bronchial fibroblasts with IL-17 and IL-19 cytokines confirmed the regulatory effect of these cytokines on SARS-CoV-2 entry receptors. Our results suggest that the type of inflammation may regulate ACE2 and TMPRSS2 expression in the lung tissue of asthmatics and may hence affect susceptibility to SARS-CoV-2 infection.

Psychological Distress and Anxiety Levels Among Health Care Workers at the Height of the COVID-19 Pandemic in the United Arab Emirates.

Objectives: Providing medical care during a global pandemic exposes healthcare workers (HCW) to a high level of risk, causing anxiety and stress. This study aimed to assess the prevalence of anxiety and psychological distress among HCWs during COVID-19. Methods: We invited HCWs from 3 hospitals across the United Arab Emirates (UAE) to participate in an anonymous online survey between April 19-May 3, 2020. The GAD-7 and K10 measures were used to assess anxiety and psychological distress. Logistic regression models assessed associations between knowledge, attitude, worry, and levels of anxiety and psychological distress. Results: A total of 481 HCWs participated in this study. The majority of HCWs were female (73.6%) and aged 25-34 years (52.6%). More than half were nurses (55.7%) and had good knowledge of COVID-19 (86.3%). Over a third (37%) of HCWs reported moderate/severe psychological distress in the K10 measure and moderate/severe anxiety (32.3%) in the GAD-7, with frontline workers significantly reporting higher levels of anxiety (36%). Knowledge of COVID-19 did not predict anxiety and psychological distress, however, HCWs who believed COVID-19 was difficult to treat and those who perceived they were at high risk of infection had worse mental health outcomes. Worry about spreading COVID-19 to family, being isolated, contracting COVID-19 and feeling stigmatized had 1.8- to 2.5-fold increased odds of symptoms of mental health problems. Additionally, HCWs who felt the need for psychological support through their workplace showed increased odds of psychological distress. Conclusion: HCWs in the UAE reported a high prevalence of psychological distress and anxiety while responding to the challenges of COVID-19. The findings from this study emphasize the public, emotional and mental health burden of COVID-19 and highlight the importance for health systems to implement, monitor, and update preventive policies to protect HCWs from contracting the virus while also providing psychological support in the workplace.

SARS-CoV-2 Switches 'on' MAPK and NFκB Signaling via the Reduction of Nuclear DUSP1 and DUSP5 Expression.

Mitogen-activated protein kinases (MAPK) and NF-kappaB (NF-κB) pathway regulate many cellular processes and are essential for immune cells function. Their activity is controlled by dual-specificity phosphatases (DUSPs). A comprehensive analysis of publicly available gene expression data sets of human airway epithelial cells (AECs) infected with SARS-CoV-2 identified DUSP1 and DUSP5 among the lowest induced transcripts within these pathways. These proteins are known to downregulate MAPK and NF-κB pathways; and their lower expression was associated with increased activity of MAPK and NF-κB signaling and enhanced expression of proinflammatory cytokines such as TNF-α. Infection with other coronaviruses did not have a similar effect on these genes. Interestingly, treatment with chloroquine and/or non-steroidal anti-inflammatory drugs counteracted the SARS-CoV-2 induced reduction of DUSP1 and DUSP5 genes expression. Therapeutically, impeding this evasion mechanism of SARS-CoV-2 may help control the exaggerated activation of these immune regulatory pathways during a COVID-19 infection.

Early administration of remdesivir to COVID-19 patients associates with higher recovery rate and lower need for ICU admission: A retrospective cohort study.

OBJECTIVES: Remdesivir is one of the most widely recommended and used medications for COVID-19 treatment. However, different outcomes have been reported for hospitalized patients with COVID-19 treated with remdesivir. Specifically, the effect of the timing of remdesivir initiation (from patient's symptom onset) on clinical outcomes in COVID-19 patients has not been investigated. METHODS: This is a retrospective cohort study of patients hospitalized with COVID-19 and treated with or without remdisivir. The primary outcome was patient's recovery rate, defined as clinical improvement and patient's discharge by day 14 of symptom onset. The secondary outcome was the need for intensive care unit (ICU) admission, mechanical ventilation, and mortality within 28 days of patient's symptom onset. RESULTS: Out of 323 hospitalized adults with COVID-19, 107 (33.1%) received no remdesivir during their hospital stay, 107 (33.1%) received remdesivir early within 7 days of the symptom onset, and 109 (33.7%) received it at 8 days or later of symptom onset. At day 14 following symptom onset, higher proportion of patients recovered in the early remdesivir compared to the late remdesivir cohort, or patients who did not receive remdesivir (adjusted odds ratio, aOR, 2.65; 95% confidence interval [CI], 1.31 to 5.35). Moreover, early administration of remdesivir was associated with lower admission to intensive care unit (adjusted hazard ratio [aHR], 0.31; 95% CI, 0.15 to 0.64), less need for mechanical ventilation (aHR, 0.22; 95% CI, 0.10 to 0.51), and lower mortality at 28 days (aHR, 0.15; 95% CI, 0.04 to 0.53), as compared to the late remdesivir cohort or patients who did not receive remdesivir. CONCLUSION: Early administration of remdesivir within 7 days of symptom onset is associated with less need for mechanical ventilation and lower 28-days mortality.

SARS-CoV-2 attenuates corticosteroid sensitivity by suppressing DUSP1 expression and activating p38 MAPK pathway.

The efficacy of corticosteroids and its use for the treatment of SARS-CoV-2 infections is controversial. In this study, using data sets of SARS-CoV-2 infected lung tissues and nasopharyngeal swabs, as well as in vitro experiments, we show that SARS-CoV-2 infection significantly downregulates DUSP1 expression. This downregulation of DUSP1 could be the mechanism regulating the enhanced activation of MAPK pathway as well as the reported steroid resistance in SARS-CoV-2 infection. Moreover, chloroquine, an off labeled COVID-19 drug is able to induce DUSP1 and attenuate MAPK pathway; and is expected to improve sensitivity to steroid treatment. However, further mechanistic studies are required to confirm this effect.

Enhanced Expression of Autoantigens During SARS-CoV-2 Viral Infection.

Immune homeostasis is disturbed during severe viral infections, which can lead to loss of tolerance to self-peptides and result in short- or long-term autoimmunity. Using publicly available transcriptomic datasets, we conducted an in-silico analyses to evaluate the expression levels of 52 autoantigens, known to be associated with 24 autoimmune diseases, during SAR-CoV-2 infection. Seven autoantigens (MPO, PRTN3, PADI4, IFIH1, TRIM21, PTPRN2, and TSHR) were upregulated in whole blood samples. MPO and TSHR were overexpressed in both lung autopsies and whole blood tissue and were associated with more severe COVID-19. Neutrophil activation derived autoantigens (MPO, PRTN3, and PADI4) were prominently increased in blood of both SARS-CoV-1 and SARS-CoV-2 viral infections, while TSHR and PTPRN2 autoantigens were specifically increased in SARS-CoV-2. Using single-cell dataset from peripheral blood mononuclear cells (PBMCs), we observed an upregulation of MPO, PRTN3, and PADI4 autoantigens within the low-density neutrophil subset. To validate our in-silico analysis, we measured plasma protein levels of two autoantigens, MPO and PRTN3, in severe and asymptomatic COVID-19. The protein levels of these two autoantigens were significantly upregulated in more severe COVID-19 infections. In conclusion, the immunopathology and severity of COVID-19 could result in transient autoimmune activation. Longitudinal follow-up studies of confirmed cases of COVID-19 could determine the enduring effects of viral infection including development of autoimmune disease.

Upregulation of oxidative stress gene markers during SARS-COV-2 viral infection.

Severe viral infections, including SARS-COV-2, could trigger disruption of the balance between pro-oxidant and antioxidant mediators; the magnitude of which could reflect the severity of infection and lung injury. Using publicly available COVID-19 transcriptomic datasets, we conducted an in-silico analyses to evaluate the expression levels of 125 oxidative stress genes, including 37 pro-oxidant genes, 32 oxidative-responsive genes, and 56 antioxidant genes. Seven oxidative stress genes were found to be upregulated in whole blood and lung autopsies (MPO, S100A8, S100A9, SRXN1, GCLM, SESN2, and TXN); these genes were higher in severe versus non-severe COVID-19 leucocytes. Oxidative genes were upregulated in inflammatory cells comprising macrophages and CD8+ T cells isolated from bronchioalveolar fluid (BALF), and neutrophils isolated from peripheral blood. MPO, S100A8, and S100A9 were top most upregulated oxidative markers within COVID-19's lung autopsies, whole blood, leucocytes, BALF derived macrophages and circulating neutrophils. The calprotectin's, S100A8 and S100A9 were upregulated in SARS-COV-2 infected human lung epithelium. To validate our in-silico analysis, we conducted qRT-PCR to measure MPO and calprotectin's levels in blood and saliva samples. Relative to uninfected donor controls, MPO, S100A8 and S100A9 were significantly higher in blood and saliva of severe versus asymptomatic COVID-19 patients. Compared to other different viral respiratory infections, coronavirus infection showed a prominent upregulation in oxidative stress genes with MPO and calprotectin at the top of the list. In conclusion, SARS-COV-2 induce the expression of oxidative stress genes via both immune as well as lung structural cells. The observed correlation between oxidative stress genes dysregulation and COVID-19 disease severity deserve more attention. Mechanistical studies are required to confirm the correlation between oxidative stress gene dysregulation, COVID-19 severity, and the net oxidative stress balance.

Combination of (interferon beta-1b, lopinavir/ritonavir and ribavirin) versus favipiravir in hospitalized patients with non-critical COVID-19: A cohort study.

OBJECTIVES: Our study aims at comparing the efficacy and safety of IFN-based therapy (lopinavir/ritonavir, ribavirin, and interferon ß-1b) vs. favipiravir (FPV) in a cohort of hospitalized patients with non-critical COVID-19. METHODS: Single center observational study comparing IFN-based therapy (interferon ß-1b, ribavirin, and lopinavir/ritonavir) vs. FPV in non-critical hospitalized COVID-19 patients. Allocation to either treatment group was non-random but based on changes to national treatment protocols rather than physicians' selection (quasi-experimental). We examined the association between IFN-based therapy and 28-day mortality using Cox regression model with treatment as a time-dependent covariate. RESULTS: The study cohort included 222 patients, of whom 68 (28%) received IFN-based therapy. Antiviral therapy was started at a median of 5 days (3-6 days) from symptoms onset in the IFN group vs. 6 days (4-7 days) for the FPV group, P <0.0001. IFN-based therapy was associated with a lower 28-day mortality as compared to FPV (6 (9%) vs. 18 (12%)), adjusted hazard ratio [aHR] (95% Cl) = 0.27 (0.08-0.88)). No difference in hospitalization duration between the 2 groups, 9 (7-14) days vs. 9 (7-13) days, P = 0.732 was found. IFN treated group required less use of systemic corticosteroids (57%) as compared to FPV (77%), P = 0.005 after adjusting for disease severity and other confounders. Patients in the IFN treated group were more likely to have nausea and diarrhea as compared to FPV group (13%) vs. (3%), P = 0.013 and (18%) vs. (3%), P<0.0001, respectively. CONCLUSION: Early IFN-based triple therapy was associated with lower 28-days mortality as compared to FPV.

The psychological impact of the COVID-19 pandemic on adults and children in the United Arab Emirates: a nationwide cross-sectional study.

BACKGROUND: The psychosocial impact of previous infectious disease outbreaks in adults has been well documented, however, there is limited information on the mental health impact of the COVID-19 pandemic on adults and children in the United Arab Emirate (UAE) community. The aim of this study was to explore anxiety levels among adults and children in the UAE and to identify potential risk and protective factors for well-being during the COVID-19 pandemic. METHODS: Using a web-based cross-sectional survey we collected data from 2200 self-selected, assessed volunteers and their children. Demographic information, knowledge and beliefs about COVID-19, generalized anxiety disorder (GAD) using the (GAD-7) scale, emotional problems in children using the strengths and difficulties questionnaire (SDQ), worry and fear about COVID-19, coping mechanisms and general health information were collected. Descriptive analysis was carried out to summarize demographic and participant characteristics, Chi-square analysis to explore associations between categorical variables and anxiety levels and multivariable binary logistic regression analysis to determine predictors of anxiety levels in adults and emotional problems in children. RESULTS: The overall prevalence of GAD in the general population was 71% with younger people (59.8%) and females (51.7%) reporting highest levels of anxiety. Parents who were teachers reported the highest percentage of emotional problems in children (26.7%). Adjusted multivariable logistic regression for GAD-7 scores showed that being female, high levels of worry associated with COVID-19, intention to take the COVID-19 vaccine and smoking were associated with higher levels of anxiety. Adjusted multivariable logistic regression for SDQ showed that higher emotional problems were reported for children in lower and higher secondary education, and parents who had severe anxiety were seven times more likely to report emotional problems in their children. CONCLUSIONS: This study reports the psychological impact of COVID-19 among adults and children in the UAE and highlights the significant association between parental and child anxiety. Findings suggest the urgency for policy makers to develop effective screening and coping strategies for parents and especially children.

Enhanced expression of immune checkpoint receptors during SARS-CoV-2 viral infection.

The immune system is tightly regulated by the activity of stimulatory and inhibitory immune receptors. This immune homeostasis is usually disturbed during chronic viral infection. Using publicly available transcriptomic datasets, we conducted in silico analyses to evaluate the expression pattern of 38 selected immune inhibitory receptors (IRs) associated with different myeloid and lymphoid immune cells during coronavirus disease 2019 (COVID-19) infection. Our analyses revealed a pattern of overall upregulation of IR mRNA during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A large number of IRs expressed on both lymphoid and myeloid cells were upregulated in nasopharyngeal swabs (NPSs), while lymphoid-associated IRs were specifically upregulated in autopsies, reflecting severe, terminal stage COVID-19 disease. Eight genes (BTLA, LAG3, FCGR2B, PDCD1, CEACAM1, CTLA4, CD72, and SIGLEC7), shared by NPSs and autopsies, were more expressed in autopsies and were directly correlated with viral levels. Single-cell data from blood and bronchoalveolar samples also reflected the observed association between IR upregulation and disease severity. Moreover, compared to SARS-CoV-1, influenza, and respiratory syncytial virus infections, the number and intensities of upregulated IRs were higher in SARS-CoV-2 infections. In conclusion, the immunopathology and severity of COVID-19 could be attributed to dysregulation of different immune inhibitors. Targeting one or more of these immune inhibitors could represent an effective therapeutic approach for the treatment of COVID-19 early and late immune dysregulations.

Effect of common medications on the expression of SARS-CoV-2 entry receptors in liver tissue.

Besides lung drastic involvement, SARS-CoV-2 severely affected other systems including liver. Emerging epidemiological studies brought the attentions towards liver injury and impairment as a potential outcome of COVID19. Angiotensin-converting enzyme 2 (ACE2) and Transmembrane serine protease (TMPRSS2) are the main cell entry receptors of SARS-CoV-2. We have tested the ability of medications to regulate expression of SARS-CoV-2 receptors. Understanding that may reflect how such medications may affect the level of infectivity and permissibility of the liver following COVID-19. Using transcriptomic datasets, Toxicogenomic Project-Genomics Assisted Toxicity Evaluation System (Open TG-GATEs) and GSE30351, we have tested the ability of ninety common medications to regulate COVID-19 receptors expression in human primary hepatocytes. Most medications displayed a dose-dependent change in expression of receptors which could hint at a potentially more pronounced change with chronic use. The expression level of TMPRSS2 was increased noticeably with a number of medications such as metformin. Within the analgesics, acetaminophen revealed a dose-dependent reduction in expression of ACE2, while non-steroidal anti-inflammatory drugs had mixed effect on receptors expression. To confirm the observed effects on primary human hepatocytes, rat hepatocyte treatments data was obtained from DrugMatrix toxicogenomic database (GSE57805), which showed a similar ACE2 and TMPRSS2 expression pattern. Treatment of common co-morbidities often require chronic use of multiple medications, which may result in an additive increase in the expression of ACE2 and TMPRSS2. More research is needed to determine the effect of different medications on COVID-19 receptors.

Effect of Common Medications on the Expression of SARS-CoV-2 Entry Receptors in Kidney Tissue.

Besides the respiratory system, severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection was shown to affect other essential organs such as the kidneys. Early kidney involvement during the course of infection was associated with worse outcomes, which could be attributed to the direct SARS-CoV-2 infection of kidney cells. In this study, the effect of commonly used medications on the expression of SARS-CoV-2 receptor, angiotensin-converting enzyme (ACE)2, and TMPRSS2 protein in kidney tissues was evaluated. This was done by in silico analyses of publicly available transcriptomic databases of kidney tissues of rats treated with multiple doses of commonly used medications. Of 59 tested medications, 56% modified ACE2 expression, whereas 24% modified TMPRSS2 expression. ACE2 was increased with only a few of the tested medication groups, namely the renin-angiotensin inhibitors, such as enalapril, antibacterial agents, such as nitrofurantoin, and the proton pump inhibitor, omeprazole. The majority of the other medications decreased ACE2 expression to variable degrees with allopurinol and cisplatin causing the most noticeable downregulation. The expression level of TMPRSS2 was increased with a number of medications, such as diclofenac, furosemide, and dexamethasone, whereas other medications, such as allopurinol, suppressed the expression of this gene. The prolonged exposure to combinations of these medications could regulate the expression of ACE2 and TMPRSS2 in a way that may affect kidney susceptibility to SARS-CoV-2 infection. Data presented here suggest that we should be vigilant about the potential effects of commonly used medications on kidney tissue expression of ACE2 and TMPRSS2.

Airways Expression of SARS-CoV-2 Receptor, ACE2, and TMPRSS2 Is Lower in Children Than Adults and Increases with Smoking and COPD.

It has been reported that angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) are the main cell entry proteins for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and play a critical role in causing coronavirus disease 2019 (COVID-19). To investigate the expression level of these SARS-CoV-2 host cell entry genes in the lung airway, we used public gene expression datasets. We have found a differential expression of ACE2 and TMPRSS2 in nasal and bronchial airways relative to age and diseases status. Children were found to have significantly lower expression of COVID-19 receptors in the upper and lower airways (nasal and bronchial). Moreover, the lung airway expression of both ACE2 and TMPRSS2 was found to be significantly upregulated in smokers compared with non-smokers, and in patients with chronic obstructive pulmonary disease (COPD) compared with healthy subjects. No difference was observed in the blood expression levels of ACE2 and TMPRSS2 between children and adults, or in COPD or diabetic patients. However, a significant increase in blood expression levels of these genes was observed in patients with essential hypertension, whereas only ACE2 was upregulated in the blood of asthmatics. These results suggest that the observed difference in COVID-19 severity between children and adults could, in part, be attributed to the difference in ACE2 and TMPRSS2 airways tissue expression levels.