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1.
Viruses ; 16(4)2024 03 31.
Article in English | MEDLINE | ID: mdl-38675889

ABSTRACT

Remdesivir (RDV) is a broad-spectrum nucleotide analog prodrug approved for the treatment of COVID-19 in hospitalized and non-hospitalized patients with clinical benefit demonstrated in multiple Phase 3 trials. Here we present SARS-CoV-2 resistance analyses from the Phase 3 SIMPLE clinical studies evaluating RDV in hospitalized participants with severe or moderate COVID-19 disease. The severe and moderate studies enrolled participants with radiologic evidence of pneumonia and a room-air oxygen saturation of ≤94% or >94%, respectively. Virology sample collection was optional in the study protocols. Sequencing and related viral load data were obtained retrospectively from participants at a subset of study sites with local sequencing capabilities (10 of 183 sites) at timepoints with detectable viral load. Among participants with both baseline and post-baseline sequencing data treated with RDV, emergent Nsp12 substitutions were observed in 4 of 19 (21%) participants in the severe study and none of the 2 participants in the moderate study. The following 5 substitutions emerged: T76I, A526V, A554V, E665K, and C697F. The substitutions T76I, A526V, A554V, and C697F had an EC50 fold change of ≤1.5 relative to the wildtype reference using a SARS-CoV-2 subgenomic replicon system, indicating no significant change in the susceptibility to RDV. The phenotyping of E665K could not be determined due to a lack of replication. These data reveal no evidence of relevant resistance emergence and further confirm the established efficacy profile of RDV with a high resistance barrier in COVID-19 patients.


Subject(s)
Adenosine Monophosphate , Adenosine Monophosphate/analogs & derivatives , Alanine , Alanine/analogs & derivatives , Antiviral Agents , COVID-19 Drug Treatment , COVID-19 , Drug Resistance, Viral , SARS-CoV-2 , Viral Load , Humans , Alanine/therapeutic use , Alanine/pharmacology , Adenosine Monophosphate/pharmacology , Adenosine Monophosphate/therapeutic use , SARS-CoV-2/drug effects , SARS-CoV-2/genetics , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Viral Load/drug effects , COVID-19/virology , Male , Female , Retrospective Studies , Middle Aged , Severity of Illness Index
2.
Data Brief ; 54: 110368, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38623552

ABSTRACT

Atlantic bottlenose dolphins are extensively studied, though little has been published regarding their occurrence patterns in the large and highly urbanized estuary of the Chesapeake Bay, USA. To address this knowledge gap, the Chesapeake DolphinWatch project was initiated in the summer of 2017. Utilizing a citizen science (also known as volunteer science) methodology, members of the public were encouraged to report dolphin sightings through a specialized mobile (iOS and Android) and web-based (https://chesapeakedolphinwatch.org) application. This approach ensured extensive, yet non-invasive and financially-efficient, data collection. The dataset presented here includes bottlenose dolphin sighting reports submitted to Chesapeake DolphinWatch by citizen scientists over five years; from June 28, 2017 through December 9, 2022. These data have been quality checked by researchers at the University of Maryland Center for Environmental Science's (UMCES) Chesapeake Biological Laboratory (CBL) in Solomons, Maryland (USA). This dataset holds potential for various applications, such as analyzing the spatiotemporal patterns of dolphin presence within the Chesapeake Bay, investigating the behavior and movements of bottlenose dolphins in the mid-Atlantic, and serving as a comparative benchmark for studies in other estuarine systems. By integrating community engagement with technological platforms, the provided data showcases the invaluable role of citizen science in advancing marine ecological research.

3.
Pediatrics ; 153(3)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38332740

ABSTRACT

OBJECTIVES: Remdesivir decreases the risk of SARS-CoV-2 infection progressing to severe disease in adults. This study evaluated remdesivir safety and pharmacokinetics in infants and children. METHODS: This was a phase 2/3, open-label trial in children aged 28 days to 17 years hospitalized for polymerase chain reaction-confirmed SARS-CoV-2 infection. Participants received for ≤10 days once-daily intravenous remdesivir doses defined using physiologically based pharmacokinetic modeling (for ≥40 kg, 200 mg day 1, then 100 mg/day; for age ≥28 days and ≥3 to <40 kg, 5 mg/kg day 1, then 2.5 mg/kg/day). Sparse pharmacokinetic samples were analyzed using population-pharmacokinetic approaches for remdesivir and metabolites GS-704277 and GS-441524. RESULTS: Among 53 participants, at enrollment the median (Q1, Q3) number of days of COVID-19 symptoms was 5 (3, 7) and hospitalization was 1 (1, 3). Underlying conditions included obesity in 19 (37%), asthma in 11 (21%), and cardiac disorders in 11 (21%). Median duration of remdesivir treatment was 5 days (range, 1-10). Remdesivir treatment had no new apparent safety trends. Two participants discontinued treatment because of adverse events including elevated transaminases; both had elevated transaminases at baseline. Three deaths occurred during treatment (and 1 after). When compared with phase 3 adult data, estimated mean pediatric parameters (area under the concentration-time curve over 1 dosing interval, AUCτ, Cmax, and Cτ) were largely overlapping but modestly increased (remdesivir, 33%-129%; GS-704277, 37%-124%; GS-441524, 0%-60%). Recovery occurred for 62% of participants on day 10 and 83% at last assessment. CONCLUSIONS: In infants and children with COVID-19, the doses of remdesivir evaluated provided drug exposure similar to adult dosing. In this study with a small sample size, no new safety concerns were observed.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , COVID-19 , Child, Hospitalized , Adult , Infant , Humans , Child , COVID-19 Drug Treatment , SARS-CoV-2 , Pyrroles , Transaminases
4.
Psychiatr Serv ; : appips20230189, 2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38369885

ABSTRACT

This Open Forum is relevant for investigators who conduct research with historically understudied and marginalized populations. The authors introduce a U.S. Department of Veterans Affairs clinical trial that experienced challenges with recruitment of African American or Black veterans and was terminated for not achieving its recruitment goals. The role of power dynamics in clinical research is discussed, specifically how unequal distributions of power may create recruitment challenges. The authors summarize three lessons learned and offer recommendations for sharing power equitably between investigators and potential participants. By recounting these experiences, the authors seek to promote culturally sensitive, veteran-centered approaches to recruitment in future clinical trials.

5.
J Exerc Sci Fit ; 22(1): 66-72, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38173796

ABSTRACT

Background: The Ireland North and South Report Card on Physical Activity (PA) for Children and Adolescents aims to monitor progress in PA participation across a range of internationally established indicators. Methods: Data were collated for 11 indicators and graded following the harmonised Active Healthy Kids Global Alliance report card process. Six representative studies (sample size range n = 898 to n = 15,557) were primarily used in the grading, with many indicators supplemented with additional studies and reports. Data collected since the implementation of COVID-19 public health measures in March 2020 were excluded. Results: Grades were awarded as follows: 'Overall physical activity', C-; 'Organised Sport and Physical Activity', C; 'Active Play', INC; 'Sedentary Behaviours', C-; 'Physical Fitness', INC; 'Family and Peers', D+; 'School', C-; 'Physical Education', D; 'Community and Environment', B+ and 'Government', B. Separate grades were awarded for disability as follows; 'Overall physical activity', F; 'Organised Sport and Physical Activity', D; 'Sedentary Behaviours', C-; 'Family and Peers', C; 'School', C- and 'Government', B. 'Active Play', 'Physical Fitness', 'Physical Education' and 'Community and Environment' were all graded INC for disability. Since the last report card in 2016, four grades remained the same, three increased ('Overall physical activity', 'School' and 'Physical Education') and two ('Family and Peers,' and 'Government') were awarded grades for the first time. Conclusion: Grades specific to children and adolescents with disability were generally lower for each indicator. While small improvements have been shown across a few indicators, PA levels remain low across many indicators for children and adolescents.

6.
J Med Chem ; 66(17): 11701-11717, 2023 09 14.
Article in English | MEDLINE | ID: mdl-37596939

ABSTRACT

Remdesivir 1 is an phosphoramidate prodrug that releases the monophosphate of nucleoside GS-441524 (2) into lung cells, thereby forming the bioactive triphosphate 2-NTP. 2-NTP, an analog of ATP, inhibits the SARS-CoV-2 RNA-dependent RNA polymerase replication and transcription of viral RNA. Strong clinical results for 1 have prompted interest in oral approaches to generate 2-NTP. Here, we describe the discovery of a 5'-isobutyryl ester prodrug of 2 (GS-5245, Obeldesivir, 3) that has low cellular cytotoxicity and 3-7-fold improved oral delivery of 2 in monkeys. Prodrug 3 is cleaved presystemically to provide high systemic exposures of 2 that overcome its less efficient metabolism to 2-NTP, leading to strong SARS-CoV-2 antiviral efficacy in an African green monkey infection model. Exposure-based SARS-CoV-2 efficacy relationships resulted in an estimated clinical dose of 350-400 mg twice daily. Importantly, all SARS-CoV-2 variants remain susceptible to 2, which supports development of 3 as a promising COVID-19 treatment.


Subject(s)
COVID-19 , Prodrugs , Chlorocebus aethiops , Humans , Animals , SARS-CoV-2 , COVID-19 Drug Treatment , Nucleosides , Prodrugs/pharmacology , Prodrugs/therapeutic use , RNA, Viral , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Furans
7.
Psychol Trauma ; 2023 Jul 06.
Article in English | MEDLINE | ID: mdl-37410415

ABSTRACT

OBJECTIVE: Military sexual trauma (MST) is prevalent among female veterans and is associated with deleterious health outcomes. Adaptive coping strategies (e.g., emotional support) are associated with more positive outcomes, while maladaptive strategies (e.g., substance use) are associated with greater impairment. However, research on factors that influence specific coping strategy use is limited. For women with a history of MST, expectancies about the effects of alcohol may enhance the use of maladaptive and reduce the use of adaptive strategies. The present study tested this hypothesis. Associations among MST status and two coping behaviors (emotional support, substance use) in female veterans were examined and the mediating role of positive alcohol expectancies on these relationships was tested. METHOD: A secondary analysis was conducted using self-report survey data from 186 female veterans in a Northeastern region. Measures included a brief screen for MST, the posttraumatic stress disorder (PTSD) Checklist for DSM-5, the Brief Cope, and the Brief Comprehensive Effects of Alcohol Questionnaire. RESULTS: Among all respondents, positive alcohol expectancies were significantly associated with greater substance use coping, while PTSD symptom severity was negatively associated with emotional support coping. Though women with MST reported greater positive alcohol expectancies and PTSD symptom severity, the direct effects of MST on coping were not significant. Mediation was not supported in our sample. CONCLUSIONS: Alcohol expectancies may be a viable target for intervention to reduce alcohol use as a maladaptive coping strategy among female veterans. Similarly, treatment targeting PTSD symptoms, regardless of MST status, is important for enhancing the use of adaptive coping strategies. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

8.
J Infect Dis ; 228(9): 1263-1273, 2023 11 02.
Article in English | MEDLINE | ID: mdl-37466213

ABSTRACT

BACKGROUND: Remdesivir is approved for treatment of coronavirus disease 2019 (COVID-19) in nonhospitalized and hospitalized adult and pediatric patients. Here we present severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) resistance analyses from the phase 3 ACTT-1 randomized placebo-controlled trial conducted in adult participants hospitalized with COVID-19. METHODS: Swab samples were collected at baseline and longitudinally through day 29. SARS-CoV-2 genomes were sequenced using next-generation sequencing. Phenotypic analysis was conducted directly on participant virus isolates and/or using SARS-CoV-2 subgenomic replicons expressing mutations identified in the Nsp12 target gene. RESULTS: Among participants with both baseline and postbaseline sequencing data, emergent Nsp12 substitutions were observed in 12 of 31 (38.7%) and 12 of 30 (40.0%) participants in the remdesivir and placebo arms, respectively. No emergent Nsp12 substitutions in the remdesivir arm were observed in more than 1 participant. Phenotyping showed low to no change in susceptibility to remdesivir relative to wild-type Nsp12 reference for the substitutions tested: A16V (0.8-fold change in EC50), P323L + V792I (2.2-fold), C799F (2.5-fold), K59N (1.0-fold), and K59N + V792I (3.4-fold). CONCLUSIONS: The similar rate of emerging Nsp12 substitutions in the remdesivir and placebo arms and the minimal change in remdesivir susceptibility among tested substitutions support a high barrier to remdesivir resistance development in COVID-19 patients. Clinical Trials Registration. NCT04280705.


Subject(s)
COVID-19 , Adult , Humans , Child , SARS-CoV-2/genetics , COVID-19 Drug Treatment , Adenosine Monophosphate/therapeutic use , Alanine/therapeutic use , Antiviral Agents/therapeutic use
9.
Infect Dis Ther ; 12(4): 1189-1203, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37074613

ABSTRACT

INTRODUCTION: In the PINETREE study, early remdesivir treatment reduced risk of coronavirus disease 2019 (COVID-19)-related hospitalizations or all-cause death versus placebo by 87% by day 28 in high-risk, non-hospitalized patients. Here we report results of assessment of heterogeneity of treatment effect (HTE) of early outpatient remdesivir, focusing on time from symptom onset and number of baseline risk factors (RFs). METHODS: PINETREE was a double-blind, placebo-controlled trial of non-hospitalized patients with COVID-19 who were randomized within 7 days of symptom onset and had ≥ 1 RF for disease progression (age ≥ 60 years, obesity [body mass index ≥ 30], or certain coexisting medical conditions). Patients received remdesivir intravenously (200 mg on day 1 and 100 mg on days 2 and 3) or placebo. RESULTS: In this subgroup analysis, HTE of remdesivir by time from symptom onset at treatment initiation and number of baseline RFs was not detected. Treatment with remdesivir reduced COVID-19-related hospitalizations independent of stratification by time from symptom onset to randomization. Of patients enrolled ≤ 5 days from symptom onset, 1/201 (0.5%) receiving remdesivir and 9/194 (4.6%) receiving placebo were hospitalized (hazard ratio [HR] 0.10; 95% confidence interval [CI] 0.01-0.82). Of those enrolled at > 5 days from symptom onset, 1/78 (1.3%) receiving remdesivir and 6/89 (6.7%) receiving placebo were hospitalized (HR 0.19; 95% CI 0.02-1.61). Remdesivir was also effective in reducing COVID-19-related hospitalizations when stratified by number of baseline RFs for severe disease. Of patients with ≤ 2 RFs, 0/159 (0.0%) receiving remdesivir and 4/164 (2.4%) receiving placebo were hospitalized; of those with ≥ 3 RFs, 2/120 (1.7%) receiving remdesivir and 11/119 (9.2%) receiving placebo were hospitalized (HR 0.16; 95% CI 0.04-0.73). CONCLUSIONS: In the outpatient setting, benefit of remdesivir initiated within 7 days of symptoms appeared to be consistent across patients with RFs. Therefore, it may be reasonable to broadly treat patients with remdesivir regardless of comorbidities. TRIAL REGISTRATION: ClinicalTrials.gov number NCT04501952.

12.
Stem Cell Reports ; 18(3): 636-653, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36827975

ABSTRACT

Ancestral SARS coronavirus-2 (SARS-CoV-2) and variants of concern (VOC) caused a global pandemic with a spectrum of disease severity. The mechanistic explaining variations related to airway epithelium are relatively understudied. Here, we biobanked airway organoids (AO) by preserving stem cell function. We optimized viral infection with H1N1/PR8 and comprehensively characterized epithelial responses to SARS-CoV-2 infection in phenotypically stable AO from 20 different subjects. We discovered Tetraspanin-8 (TSPAN8) as a facilitator of SARS-CoV-2 infection. TSPAN8 facilitates SARS-CoV-2 infection rates independently of ACE2-Spike interaction. In head-to-head comparisons with Ancestral SARS-CoV-2, Delta and Omicron VOC displayed lower overall infection rates of AO but triggered changes in epithelial response. All variants shared highest tropism for ciliated and goblet cells. TSPAN8-blocking antibodies diminish SARS-CoV-2 infection and may spur novel avenues for COVID-19 therapy.


Subject(s)
COVID-19 , Influenza A Virus, H1N1 Subtype , Humans , SARS-CoV-2 , Organoids , Tetraspanins/genetics
13.
Adapt Phys Activ Q ; 40(3): 504-512, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-36400024

ABSTRACT

For the first time, data on children and adolescents with disabilities in Ireland are reported based on the Active Healthy Kids Global Alliance Para Report Card methodology. The most recent data from the last 10 years were used in the grading process (A+ to F), and indicators with insufficient data were graded as incomplete. Of the 10 indicators from the Global Matrix Para Report Cards, grades were assigned to Overall Physical Activity (F), Organized Sport (D), Active Transport (D-), Sedentary Behaviors (D-), Family & Peers (C), School (C-), Community & Environment (B-), and Government (B). Irish disability sport organizations were invited to assess the research-led audit and provided commentary around the final grading. The contextual discussion of the grades is presented through the lens of strengths, weaknesses, opportunities, and threats with the purpose being to provide direction for the reduction of physical activity disparities among children with disabilities.


Subject(s)
Disabled Persons , Sports , Child , Humans , Adolescent , Health Promotion , Health Policy , Exercise
14.
Med Sci Educ ; 32(6): 1309-1312, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36415503

ABSTRACT

To prepare medical students for leadership roles, medical student organizations should provide longitudinal leadership opportunities spanning the entire duration of the medical school curriculum. These long-term roles need to be adaptable to medical students' changing and busy schedules, provide a robust structure for communication, improve access to resources and mentors, and allow autonomy for individual decisions to facilitate effective engagement as a leader. We describe the design of a student-led organization, PhysioCamp, which facilitates opportunities for longitudinal medical student leadership through an internship program for high school graduates.

15.
J Behav Ther Exp Psychiatry ; 77: 101772, 2022 12.
Article in English | MEDLINE | ID: mdl-36113909

ABSTRACT

BACKGROUND AND OBJECTIVES: Affective responses to trauma cues in individuals with posttraumatic stress (PTS) can evoke a desire to drink and may shed light on novel mechanisms of PTS-drinking. The present study aimed to (1) identify and characterize patterns of acute emotional responses (ER) to trauma cues and (2) examine how these patterns influence drinking urge. METHODS: University students (N = 304; Mage = 19; 52.3% female) completed a structured clinical interview to confirm trauma history and PTS. At an experimental session one week later, participants completed a series of three trauma cue exposures. Affect and drinking urge were measured at baseline, after each cue exposure, and at experiment's end. RESULTS: Latent profile analysis of ER yielded a five-profile solution: (1) Nonresponders (2) Low Responders (3) Moderate Responders (4) Resilient Responders and (5) High Responders. Profiles differed by trait neuroticism, PTS, and emotion dysregulation, with High Responders as the most severe group. In latent growth curve models, profiles significantly predicted alcohol urge trajectories in a graded pattern. High Responders, with the greatest affective intensity, showed the strongest urge. Duration of affect was also implicated with Resilient Responders, who had similar intensity but faster overall affective recovery time compared to High Responders, demonstrating lower mean levels of urge. LIMITATIONS: External validity is limited. CONCLUSIONS: Individual differences in ER to trauma cues are important for understanding alcohol urge. Findings can inform integrative treatments for PTS-drinking by targeting ER to shorten affective recovery to trauma reminders and reduce the need for alcohol use as a regulation strategy.


Subject(s)
Cues , Emotions , Adult , Ethanol , Female , Humans , Male , Young Adult
16.
bioRxiv ; 2022 Aug 02.
Article in English | MEDLINE | ID: mdl-35982664

ABSTRACT

As SARS-CoV-2 continues to spread worldwide, tractable primary airway cell models that accurately recapitulate the cell-intrinsic response to arising viral variants are needed. Here we describe an adult stem cell-derived human airway organoid model overexpressing the ACE2 receptor that supports robust viral replication while maintaining 3D architecture and cellular diversity of the airway epithelium. ACE2-OE organoids were infected with SARS-CoV-2 variants and subjected to single-cell RNA-sequencing. NF-κB inhibitor alpha was consistently upregulated in infected epithelial cells, and its mRNA expression positively correlated with infection levels. Confocal microscopy showed more IκBα expression in infected than bystander cells, but found concurrent nuclear translocation of NF-κB that IκBα usually prevents. Overexpressing a nondegradable IκBα mutant reduced NF-κB translocation and increased viral infection. These data demonstrate the functionality of ACE2-OE organoids in SARS-CoV-2 research and identify an incomplete NF-κB feedback loop as a rheostat of viral infection that may promote inflammation and severe disease.

17.
Am J Respir Crit Care Med ; 206(8): 961-972, 2022 10 15.
Article in English | MEDLINE | ID: mdl-35649173

ABSTRACT

Rationale: Autopsy and biomarker studies suggest that endotheliopathy contributes to coronavirus disease (COVID-19)-associated acute respiratory distress syndrome. However, the effects of COVID-19 on the lung endothelium are not well defined. We hypothesized that the lung endotheliopathy of COVID-19 is caused by circulating host factors and direct endothelial infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Objectives: We aimed to determine the effects of SARS-CoV-2 or sera from patients with COVID-19 on the permeability and inflammatory activation of lung microvascular endothelial cells. Methods: Human lung microvascular endothelial cells were treated with live SARS-CoV-2; inactivated viral particles; or sera from patients with COVID-19, patients without COVID-19, and healthy volunteers. Permeability was determined by measuring transendothelial resistance to electrical current flow, where decreased resistance signifies increased permeability. Inflammatory mediators were quantified in culture supernatants. Endothelial biomarkers were quantified in patient sera. Measurements and Main Results: Viral PCR confirmed that SARS-CoV-2 enters and replicates in endothelial cells. Live SARS-CoV-2, but not dead virus or spike protein, induces endothelial permeability and secretion of plasminogen activator inhibitor 1 and vascular endothelial growth factor. There was substantial variability in the effects of SARS-CoV-2 on endothelial cells from different donors. Sera from patients with COVID-19 induced endothelial permeability, which correlated with disease severity. Serum levels of endothelial activation and injury biomarkers were increased in patients with COVID-19 and correlated with severity of illness. Conclusions: SARS-CoV-2 infects and dysregulates endothelial cell functions. Circulating factors in patients with COVID-19 also induce endothelial cell dysfunction. Our data point to roles for both systemic factors acting on lung endothelial cells and viral infection of endothelial cells in COVID-19-associated endotheliopathy.


Subject(s)
COVID-19 , Vascular Diseases , Biomarkers/metabolism , Endothelial Cells/metabolism , Humans , Inflammation Mediators/metabolism , Lung , Plasminogen Activator Inhibitor 1/metabolism , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/metabolism , Vascular Diseases/metabolism , Vascular Endothelial Growth Factor A/metabolism
18.
Antimicrob Agents Chemother ; 66(6): e0022222, 2022 06 21.
Article in English | MEDLINE | ID: mdl-35532238

ABSTRACT

Genetic variation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in the emergence and rapid spread of multiple variants throughout the pandemic, of which Omicron is currently the predominant variant circulating worldwide. SARS-CoV-2 variants of concern/variants of interest (VOC/VOI) have evidence of increased viral transmission, disease severity, or decreased effectiveness of vaccines and neutralizing antibodies. Remdesivir (RDV [VEKLURY]) is a nucleoside analog prodrug and the first FDA-approved antiviral treatment of COVID-19. Here, we present a comprehensive antiviral activity assessment of RDV and its parent nucleoside, GS-441524, against 10 current and former SARS-CoV-2 VOC/VOI clinical isolates by nucleoprotein enzyme-linked immunosorbent assay (ELISA) and plaque reduction assay. Delta and Omicron variants remained susceptible to RDV and GS-441524, with 50% effective concentration (EC50) values 0.30- to 0.62-fold of those observed against the ancestral WA1 isolate. All other tested variants exhibited EC50 values ranging from 0.13- to 2.3-fold of the observed EC50 values against WA1. Analysis of nearly 6 million publicly available variant isolate sequences confirmed that Nsp12, the RNA-dependent RNA polymerase (RdRp) target of RDV and GS-441524, is highly conserved across variants, with only 2 prevalent changes (P323L and G671S). Using recombinant viruses, both RDV and GS-441524 retained potency against all viruses containing frequent variant substitutions or their combination. Taken together, these results highlight the conserved nature of SARS-CoV-2 Nsp12 and provide evidence of sustained SARS-CoV-2 antiviral activity of RDV and GS-441524 across the tested variants. The observed pan-variant activity of RDV supports its continued use for the treatment of COVID-19 regardless of the SARS-CoV-2 variant.


Subject(s)
COVID-19 Drug Treatment , SARS-CoV-2 , Adenosine/analogs & derivatives , Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/pharmacology , Humans , SARS-CoV-2/genetics
19.
bioRxiv ; 2022 May 11.
Article in English | MEDLINE | ID: mdl-35592107

ABSTRACT

In the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, considerable focus has been placed on a model of viral entry into host epithelial populations, with a separate focus upon the responding immune system dysfunction that exacerbates or causes disease. We developed a precision-cut lung slice model to investigate very early host-viral pathogenesis and found that SARS-CoV-2 had a rapid and specific tropism for myeloid populations in the human lung. Infection of alveolar macrophages was partially dependent upon their expression of ACE2, and the infections were productive for amplifying virus, both findings which were in contrast with their neutralization of another pandemic virus, Influenza A virus (IAV). Compared to IAV, SARS-CoV-2 was extremely poor at inducing interferon-stimulated genes in infected myeloid cells, providing a window of opportunity for modest titers to amplify within these cells. Endotracheal aspirate samples from humans with the acute respiratory distress syndrome (ARDS) from COVID-19 confirmed the lung slice findings, revealing a persistent myeloid depot. In the early phase of SARS-CoV-2 infection, myeloid cells may provide a safe harbor for the virus with minimal immune stimulatory cues being generated, resulting in effective viral colonization and quenching of the immune system.

20.
Res Sq ; 2022 May 17.
Article in English | MEDLINE | ID: mdl-35611333

ABSTRACT

In the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic1, considerable focus has been placed on a model of viral entry into host epithelial populations, with a separate focus upon the responding immune system dysfunction that exacerbates or causes disease. We developed a precision-cut lung slice model2,3 to investigate very early host-viral pathogenesis and found that SARS-CoV-2 had a rapid and specific tropism for myeloid populations in the human lung. Infection of alveolar macrophages was partially dependent upon their expression of ACE2, and the infections were productive for amplifying virus, both findings which were in contrast with their neutralization of another pandemic virus, Influenza A virus (IAV). Compared to IAV, SARS-CoV-2 was extremely poor at inducing interferon-stimulated genes in infected myeloid cells, providing a window of opportunity for modest titers to amplify within these cells. Endotracheal aspirate samples from humans with the acute respiratory distress syndrome (ARDS) from COVID-19 confirmed the lung slice findings, revealing a persistent myeloid depot. In the early phase of SARS-CoV-2 infection, myeloid cells may provide a safe harbor for the virus with minimal immune stimulatory cues being generated, resulting in effective viral colonization and quenching of the immune system.

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