Severe Acute Respiratory Syndrome Research Articles

Efficient overexpression and purification of SARS-CoV-2 Nucleocapsid proteins in Escherichia coli.

The fundamental biology of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) nucleocapsid protein (Ncap), its use in diagnostic assays and its potential application as a vaccine component have received considerable attention since the outbreak of the Covid19 pandemic in late 2019. Here we report the scalable expression and purification of soluble, immunologically active, SARS-CoV-2 Ncap in Escherichia coli. Codon-optimised synthetic genes encoding the original Ncap sequence and four common variants with an N-terminal 6His affinity tag (sequence MHHHHHHG) were cloned into an inducible expression vector carrying a regulated bacteriophage T5 synthetic promoter controlled by lac operator binding sites. The constructs were used to express Ncap proteins and protocols developed which allow efficient production of purified Ncap with yields of over 200 mg per litre of culture media. These proteins were deployed in ELISA assays to allow comparison of their responses to human sera. Our results suggest that there was no detectable difference between the 6His-tagged and untagged original Ncap proteins but there may be a slight loss of sensitivity of sera to other Ncap isolates.

Seasonality of respiratory, enteric, and urinary viruses revealed by wastewater genomic surveillance.

Wastewater surveillance can reveal population-level infectious disease burden and emergent public health threats can be reliably assessed through wastewater surveillance. While molecular methods for wastewater monitoring of microorganisms have traditionally relied on PCR-based approaches, next-generation sequencing (NGS) can provide deeper insights via genomic analyses of multiple diverse pathogens. We conducted a year-long sequencing surveillance of 1,408 composite wastewater samples collected from 12 neighborhood-level access points in the greater Tempe area, Arizona, USA, and show that variation in wastewater viruses is driven by seasonal time and location. The temporal dynamics of viruses in wastewater were influenced cyclically, with the most dissimilarity between samples 23 weeks apart (i.e., winter vs summer, spring vs fall). We identified diverse urinary and enteric viruses including polyomaviruses, astroviruses, and noroviruses, and showed that their genotypes/subtypes shifted across seasons. We show that while wastewater data of certain respiratory viruses like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strongly correlate with clinical case rates, laboratory-reported case incidences were discordant with surges of high viral load in wastewater for other viruses like human coronavirus 229E. These results demonstrate the utility of wastewater sequencing for informing decision-making in public health.IMPORTANCEWastewater surveillance can provide insights into the spread of pathogens in communities. Advances in next-generation sequencing (NGS) methodologies allow for more precise detection of viruses in wastewater. Long-term wastewater surveillance of viruses is an important tool for public health preparedness. This system can act as a public health observatory that gives real-time early warning for infectious disease outbreaks and improved response times.

Wastewater monitoring of SARS-CoV-2 gene for COVID-19 epidemiological surveillance in Tucumán, Argentina.

Wastewater-based epidemiology provides temporal and spatial information about the health status of a population. The objective of this study was to analyze and report the epidemiological dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the province of Tucumán, Argentina during the second and third waves of coronavirus disease 2019 (COVID-19) between April 2021 and March 2022. The study aimed to quantify SARS-CoV-2 RNA in wastewater, correlating it with clinically reported COVID-19 cases. Wastewater samples (n = 72) were collected from 16 sampling points located in three cities of Tucumán (San Miguel de Tucumán, Yerba Buena y Banda del Río Salí). Detection of viral nucleocapsid markers (N1 gene) was carried out using one-step reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Viral loads were determined for each positive sample using a standard curve. A positive correlation (p < 0.05) was observed between viral load (copies/mL) and the clinically confirmed COVID-19 cases reported at specific sampling points in San Miguel de Tucumán (SP4, SP7, and SP8) in both months, May and June. Indeed, the high viral load concurred with the peaks of COVID-19 cases. This method allowed us to follow the behavior of SARS-CoV-2 infection during epidemic outbreaks. Thus, wastewater monitoring is a valuable epidemiological indicator that enables the anticipation of increases in COVID-19 cases and tracking the progress of the pandemic. SARS-CoV-2 genome-based surveillance should be implemented as a routine practice to prepare for any future surge in infections.

Hemorrhage and thrombosis in COVID-19-patients supported with extracorporeal membrane oxygenation: an international study based on the COVID-19 critical care consortium

BackgroundExtracorporeal membrane oxygenation (ECMO) is a rescue therapy in patients with severe acute respiratory distress syndrome (ARDS) secondary to COVID-19. While bleeding and thrombosis complicate ECMO, these events may also occur secondary to COVID-19. Data regarding bleeding and thrombotic events in COVID-19 patients on ECMO are sparse.MethodsUsing the COVID-19 Critical Care Consortium database, we conducted a retrospective analysis on adult patients with severe COVID-19 requiring ECMO, including centers globally from 01/2020 to 06/2022, to determine the risk of ICU mortality associated with the occurrence of bleeding and clotting disorders.ResultsAmong 1,248 COVID-19 patients receiving ECMO support in the registry, coagulation complications were reported in 469 cases (38%), among whom 252 (54%) experienced hemorrhagic complications, 165 (35%) thrombotic complications, and 52 (11%) both. The hazard ratio (HR) for Intensive Care Unit mortality was higher in those with hemorrhagic-only complications than those with neither complication (adjusted HR = 1.60, 95% CI 1.28–1.99, p < 0.001). Death was reported in 617 of the 1248 (49.4%) with multiorgan failure (n = 257 of 617 [42%]), followed by respiratory failure (n = 130 of 617 [21%]) and septic shock [n = 55 of 617 (8.9%)] the leading causes.ConclusionsCoagulation disorders are frequent in COVID-19 ARDS patients receiving ECMO. Bleeding events contribute substantially to mortality in this cohort. However, this risk may be lower than previously reported in single-nation studies or early case reports.Trial registration ACTRN12620000421932 (https://covid19.cochrane.org/studies/crs-13513201).

Human coronavirus OC43 nanobody neutralizes virus and protects mice from infection.

The pandemic potential presented by coronaviruses has been demonstrated by the ongoing COVID-19 pandemic and previous epidemics caused by severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus. Outside of these major pathogenic coronaviruses, there are four endemic coronaviruses that infect humans: hCoV-OC43, hCoV-229E, hCoV-HKU1, and hCoV-NL63. We identified a collection of nanobodies against human coronavirus OC43 (hCoV-OC43) and found that two high-affinity nanobodies potently neutralized hCoV-OC43 at low nanomolar concentrations. Prophylactic administration of one neutralizing nanobody reduced viral loads in mice infected with hCoV-OC43, showing the potential for nanobody-based therapies for hCoV-OC43 infections.

Diagnostic Accuracy of Conjunctival Rt-Pcr in Sars-Cov-2: A Systematic Review and Diagnostic Accuracy Meta-Analysis

ABSTRACT Purpose To study the positivity rate of conjunctival realtime polymerase chain reaction (RT-PCR) testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Design Systematic review and diagnostic accuracy meta-analysis. Methods MEDLINE and EMBASE were queried using medical subject headings terms. Diagnostic accuracy meta-analyses and forest plots were obtained using the RevMan software. Results After deduplication, appraisal of abstract titles and full-text analysis of 1441 articles, 42 articles with 3351 COVID-19 patients were included in this review. Of these, 412 conjunctival swabs/Schirmer paper strips tested positive for SARS-CoV-2 by RT-PCR. The pooled sensitivity of the RT-PCR tests across the 24 studies with laboratory-confirmed COVID-19 patients was 10.3%. Conclusions Only 1 in 10 RT-PCR tests performed on conjunctival swabs were positive for SARS-CoV-2. Although this suggests that SARS-CoV-2 is likely present and detectable in the conjunctiva, this detection method has low diagnostic potential.

Multiple E3 ligases act as antiviral factors against SARS-CoV-2 via inducing the ubiquitination and degradation of ORF9b.

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) open reading frame 9b (ORF9b) antagonizes the antiviral type I and III interferon (IFN) responses and is ubiquitinated and degraded via the ubiquitin-proteasome pathway. However, E3 ubiquitin ligases that mediate the polyubiquitination and degradation of ORF9b remain unknown. In this study, we identified 14 E3 ligases that specifically bind to SARS-CoV-2 ORF9b. Specifically, three E3 ligases, HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 (HUWE1), ubiquitin protein ligase E3 component n-recognin 4 (UBR4), and UBR5, induced K48-linked polyubiquitination and degradation of ORF9b, thereby attenuating ORF9b-mediated inhibition of the IFN response and SARS-CoV-2 replication. Moreover, each E3 ligase performed this function independent of the other two E3 ligases. Therefore, the three E3 ligases identified in this study as anti-SARS-CoV-2 host factors provide novel molecular insight into the virus-host interaction.IMPORTANCEUbiquitination is an important post-translational modification that regulates multiple biological processes, including viral replication. Identification of E3 ubiquitin ligases that target viral proteins for degradation can provide novel targets for antagonizing viral infections. Here, we identified multiple E3 ligases, including HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 (HUWE1), ubiquitin protein ligase E3 component n-recognin 4 (UBR4), and UBR5, that ubiquitinated and induced the degradation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) open reading frame 9b (ORF9b), an interferon (IFN) antagonist, thereby enhancing IFN production and attenuating SARS-CoV-2 replication. Our study provides new possibilities for drug development targeting the interaction between E3 ligases and ORF9b.

Host factors influencing variable symptoms of COVID-19.

Similar to many other viruses, SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) causes various symptoms in individuals who have been exposed to the virus. Individuals exposed to the virus can be asymptomatic, mild, severe, and critical for mortality. Most hypotheses explaining the uncertainty of symptoms are based on innate immunity, which is unclear in explaining some issues. For example, 1. uncertain symptoms of SARS-CoV-2 infection, 2. failure to induce immunity for prevention by vaccines in some individuals, and 3. repeated infections in some individuals. With the ambition of explaining this clearly, this article proposed another perspective to explain the cause of uncertain symptoms in SARS-CoV-2-positive individuals. This could be influenced by host factors with a variety of cellular molecules (viral receptors/co-receptors) and major histocompatibility complex (MHC) polymorphisms, which are crucial factors in explaining this question. Hopefully, this perspective could encourage further research and pave the way for developing new public health policies to deal with COVID-19 and emergent viral epidemics in the future.

Variant-specific Symptoms After COVID-19: A Hospital-based Study in Hiroshima.

Symptoms after novel coronavirus disease 2019 (COVID-19) recovery by severe acute respiratory syndrome coronavirus 2 strains are unspecified. This self-administered questionnaire-based study was conducted to investigate symptoms after COVID-19 recovery at one of the main hospitals for COVID-19 treatment in Hiroshima, Japan, from September 2020 to March 2022 for patients who visited follow-up consultations after COVID-19. Study subjects were divided into four groups (Wild-type, Alpha, Delta, and Omicron periods) according to COVID-19 onset date. Hierarchical cluster analysis was performed to determine symptom clusters and investigate risk factors for each symptom cluster using multivariate analysis. Among 385 patients who enrolled in this study, 249 patients had any persistent symptoms at a median of 23.5 (interquartile range, 20-31) days after COVID-19 onset. Among patients with any persistent symptoms, symptom clusters including olfactory or taste disorders, respiratory symptoms, and cardiac symptoms were found. Respiratory symptoms were more frequent among patients infected in the Omicron period compared to the Wild-type period (adjusted odds ratio [AOR] 3.13; 95% confidence interval [CI], 1.31-7.48). Compared to patients who recovered from mild COVID-19, patients who needed oxygen or ventilation support suffered fewer post-COVID-19 respiratory symptoms (AOR 0.46; 95% CI, 0.22-0.97) but more post-COVID-19 cardiac symptoms among them (AOR 2.67; 95% CI, 1.26-5.65). Olfactory or taste disorders were fewer among patients infected in the Omicron period compared to the Wild-type period (AOR 0.14; 95% CI, 0.04-0.46). This study revealed that symptoms after COVID-19 may vary depending on the infected strain.

Efficacy, Safety, and Pharmacokinetics of AZD7442 (Tixagevimab/Cilgavimab) for Prevention of Symptomatic COVID-19: 15-Month Final Analysis of the PROVENT and STORM CHASER Trials.

The phase3 PROVENT and STORM CHASER studies evaluated AZD7442 (tixagevimab/cilgavimab) for pre-exposure and post-exposure prophylaxis of symptomatic coronavirus disease 2019 (COVID-19). We report the final 15-month results of both studies. In PROVENT, participants were randomized 2:1 to receive 300mg AZD7442 (n = 3460) or placebo (n = 1737). In STORM CHASER, participants were enrolled within 8days of exposure to a severe acute respiratory syndrome coronavirus2 (SARS-CoV-2)-infected individual and randomized 2:1 to receive 300mg AZD7442 (n = 749) or placebo (n = 372). In PROVENT, the relative risk reduction (RRR) in symptomatic COVID-19 for AZD7442 versus placebo was 76.7% at primary analysis [95% confidence interval (CI) 46.1, 90.0; p < 0.001], 83.0% at day183 (95%CI 67.3, 91.2; nominal p < 0.001), and 46.3% at day366 (95%CI 23.1, 62.4; nominal p < 0.001). Severe/critical COVID-19 was reduced by 91.4% with AZD7442 versus placebo by day366 (95%CI 61.3, 98.1; nominal p < 0.0001). Adverse events (AEs) occurred in 58.2% and 58.0% of participants administered AZD7442 or placebo, respectively; serious AEs (SAEs) occurred in 6.2% and 5.6%, respectively. In STORM CHASER, the RRR in symptomatic COVID-19 for AZD7442 versus placebo was 33.3% at primary analysis (95%CI - 25.9, 64.7; p = 0.212), 43.3% at day183 (95%CI 1.4, 67.4; nominal p = 0.044) and 3.4% at day366 (95%CI - 35.6, 31.2; nominal p = 0.842). Severe/critical COVID-19 did not occur in participants receiving AZD7442 versus 0.5% of participants receiving placebo by day366. AEs occurred in 46.5% and 51.9% of participants administered AZD7442 or placebo, respectively; SAEs occurred in 2.7% and 4.3%, respectively. In both studies, serum concentration-time profiles over 457days were similar for tixagevimab and cilgavimab and consistent with the extended half-life reported for AZD7442 (approximately 90days). This analysis provides proof of concept supporting long-term safety of intramuscularly administered AZD7442 for prevention of symptomatic/severe COVID-19. A graphical abstract is available with this article. PROVENT (NCT04625725) and STORM CHASER (NCT04625972).

Emerging Trends of Gold Nanostructures for Point-of-Care Biosensor-Based Detection of COVID-19.

In 2019, a worldwide pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged. SARS-CoV-2 is the deadly microorganism responsible for coronavirus disease 2019 (COVID-19), which has caused millions of deaths and irreversible health problems worldwide. To restrict the spread of SARS-CoV-2, accurate detection of COVID-19 is essential for the identification and control of infected cases. Although recent detection technologies such as the real-time polymerase chain reaction delivers an accurate diagnosis of SARS-CoV-2, they require a long processing duration, expensive equipment, and highly skilled personnel. Therefore, a rapid diagnosis with accurate results is indispensable to offer effective disease suppression. Nanotechnology is the backbone of current science and technology developments including nanoparticles (NPs) that can biomimic the corona and develop deep interaction with its proteins because of their identical structures on the nanoscale. Various NPs have been extensively applied in numerous medical applications, including implants, biosensors, drug delivery, and bioimaging. Among them, point-of-care biosensors mediated with gold nanoparticles (GNPSs) have received great attention due to their accurate sensing characteristics, which are widely used in the detection of amino acids, enzymes, DNA, and RNA in samples. GNPS have reconstructed the biomedical application of biosensors because of its outstanding physicochemical characteristics. This review provides an overview of emerging trends in GNP-mediated point-of-care biosensor strategies for diagnosing various mutated forms of human coronaviruses that incorporate different transducers and biomarkers. The review also specifically highlights trends in gold nanobiosensors for coronavirus detection, ranging from the initial COVID-19 outbreak to its subsequent evolution into a pandemic.

Immunoinformatics design of a structural proteins driven multi-epitope candidate vaccine against different SARS-CoV-2 variants based on fynomer

The ideal vaccines for combating diseases that may emerge in the future require more than simply inactivating a few pathogenic strains. This study aims to provide a peptide-based multi-epitope vaccine effective against various severe acute respiratory syndrome coronavirus 2 strains. To design the vaccine, a library of peptides from the spike, nucleocapsid, membrane, and envelope structural proteins of various strains was prepared. Then, the final vaccine structure was optimized using the fully protected epitopes and the fynomer scaffold. Using bioinformatics tools, the antigenicity, allergenicity, toxicity, physicochemical properties, population coverage, and secondary and three-dimensional structures of the vaccine candidate were evaluated. The bioinformatic analyses confirmed the high quality of the vaccine. According to further investigations, this structure is similar to native protein and there is a stable and strong interaction between vaccine and receptors. Based on molecular dynamics simulation, structural compactness and stability in binding were also observed. In addition, the immune simulation showed that the vaccine can stimulate immune responses similar to real conditions. Finally, codon optimization and in silico cloning confirmed efficient expression in Escherichia coli. In conclusion, the fynomer-based vaccine can be considered as a new style in designing and updating vaccines to protect against coronavirus disease.

SARS-CoV-2-specific T cell responses: a comparative analysis between QuantiFERON SARS-CoV-2, T-SPOT.COVID, and an in-house Omicron ELISpot.

T cell immunity plays a pivotal role in mitigating the severity of coronavirus disease 2019 (COVID-19). Therefore, reliable functional T cell assays are required to evaluate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cell immunity in specific patient populations. We recruited a cohort of 23 healthcare workers who received their bivalent Omicron BA.1 / ancestral mRNA booster vaccination or were infected with the Omicron variant at a median of 144 days and 227 days before blood collection, respectively. In this cohort, we compared the performances of two widely utilized commercial SARS-CoV-2 interferon-gamma release assays (IGRAs), i.e., QuantiFERON SARS-CoV-2 and T-SPOT.COVID, and an in-house designed Omicron enzyme-linked immunospot (ELISpot). The QuantiFERON SARS-CoV-2 and T-SPOT.COVID assays detected SARS-CoV-2 spike-specific T cells in 34.8% and 21.7% of participants, respectively. Moreover, our in-house designed ELISpot that included Omicron BA.4 and BA.5 full-spike peptides detected T cell responses in 47.8% of participants and was strongly associated with the T-SPOT.COVID. The evaluation of SARS-CoV-2 T cell immunity using commercially accessible assays may yield disparate outcomes as results from different assays are not directly comparable. A specific Omicron ELISpot should be considered to assess Omicron-specific T cell immunity.

Prone positioning does not improve outcomes of intubated patients with pneumocystis pneumonia and moderate–severe acute respiratory distress syndrome: a single-center, retrospective, observational, cohort study

BackgroundPneumocystis pneumonia is an uncommon precipitant of acute respiratory distress syndrome and is associated with high mortality. Prone positioning ventilation has been proven to reduce mortality in patients with moderate–severe acute respiratory distress syndrome. We investigated the effect of prone positioning on oxygenation and mortality in intubated patients with pneumocystis pneumonia comorbid with moderate–severe acute respiratory distress syndrome.MethodsIn this single-center, retrospective, observational, cohort study, eligible patients were enrolled at West China Hospital of Sichuan University from January 1, 2017, to December 31, 2021. Data on demographics, clinical features, ventilation parameters, arterial blood gas, and outcomes were collected. Patients were assigned to the prone cohort or supine cohort according to whether they received prone positioning ventilation. The main outcome was 28-day mortality.FindingsA total of 79 patients were included in the study. Sixty-three patients were enrolled in the prone cohort, and 16 patients were enrolled in the supine cohort. The 28-day mortality was 61.9% in the prone cohort and 68.8% in the supine cohort (P = 0.26), and 90-day mortality was 66.7% in the prone cohort and 68.8% in the supine cohort (P = 0.55). Patients in the supine cohort had fewer invasive mechanical ventilation days and more ventilator-free days. The incidence of complications was higher in the prone cohort than in the supine cohort.ConclusionsIn patients with pneumocystis pneumonia and moderate–severe acute respiratory distress syndrome, prone positioning did not decrease 28-day or 90-day mortality.Trial registration ClinicalTrials.gov number, ChiCTR2200063889. Registered on 20 September 2022, https://www.chictr.org.cn/showproj.html?proj=174886.

Immune Responses to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Vaccines: Updated Insights

Background: Using a multidisciplinary approach, this review explores and investigates the relationship between immune responses, effectiveness, and results of various vaccination strategies among a range of demographics. Moreover, this review aims to aid healthcare professionals in understanding the intricacies of immune responses and their implications for future vaccine development.Methodology: In this systematic review, we employed an electronic online database platform including the National Centre for Biotechnology Information (NCBI), the National Institute for Health and Clinical Excellence (NICE), and the World Health Organization (WHO) for evidence-based material, utilizing the keywords throughout this literature review.Results: This review provides a detailed framework regarding immune responses to the COVID- 19 vaccine, based on demographics, age, sex, types of immunity, and immunization strategies. Such research can provide important academic support for the development of not only COVID- 19 vaccines but also other vaccines.Conclusions: Overall, immune responses tended to dwindle a few months after vaccine administration. This is because B cells block SARS-CoV-2 from infecting cells via antibodies and T cells destroy infected cells. The most efficient tool for providing long-lasting protection against SARS-CoV-2 is vaccination. Humans have developed immunity to SARS-CoV-2, particularly antibody-mediated humoral immunity. The development of vaccines across the whole family of coronaviruses that target antibody epitopes (antigenic determinants) prevents the emergence of mutant strains.

Transfected SARS-CoV-2 spike DNA for mammalian cell expression inhibits p53 activation of p21(WAF1), TRAIL Death Receptor DR5 and MDM2 proteins in cancer cells and increases cancer cell viability after chemotherapy exposure.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and COVID-19 infection has led to worsened outcomes for patients with cancer. SARS-CoV-2 spike protein mediates host cell infection and cell-cell fusion that causes stabilization of tumor suppressor p53 protein. In-silico analysis previously suggested that SARS-CoV-2 spike interacts with p53 directly but this putative interaction has not been demonstrated in cells. We examined the interaction between SARS-CoV-2 spike, p53 and MDM2 (E3 ligase, which mediates p53 degradation) in cancer cells using an immunoprecipitation assay. We observed that SARS-CoV-2 spike protein interrupts p53-MDM2 protein interaction but did not detect SARS-CoV-2 spike bound with p53 protein in the cancer cells. We further observed that SARS-CoV-2 spike suppresses p53 transcriptional activity in cancer cells including after nutlin exposure of wild-type p53-, spike-expressing tumor cells and inhibits chemotherapy-induced p53 gene activation of p21(WAF1), TRAIL Death Receptor DR5 and MDM2. The suppressive effect of SARS-CoV-2 spike on p53-dependent gene activation provides a potential molecular mechanism by which SARS-CoV-2 infection may impact tumorigenesis, tumor progression and chemotherapy sensitivity. In fact, cisplatin-treated tumor cells expressing spike were found to have increased cell viability as compared to control cells. Further observations on γ-H2AX expression in spike-expressing cells treated with cisplatin may indicate altered DNA damage sensing in the DNA damage response pathway. The preliminary observations reported here warrant further studies to unravel the impact of SARS-CoV-2 and its various encoded proteins including spike on pathways of tumorigenesis and response to cancer therapeutics. More efforts should be directed at studying the effects of the SARS-CoV-2 spike and other viral proteins on host DNA damage sensing, response and repair mechanisms. A goal would be to understand the structural basis for maximal anti-viral immunity while minimizing suppression of host defenses including the p53 DNA damage response and tumor suppression pathway. Such directions are relevant and important including not only in the context of viral infection and mRNA vaccines in general but also for patients with cancer who may be receiving cytotoxic or other cancer treatments.

A Piecewise Design Approach to Engineering a Miniature ACE2 Mimic to Bind SARS-CoV-2.

As the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues its global spread, the exploration of novel therapeutic and diagnostic strategies is still needed. The virus enters host cells by binding the angiotensin-converting enzyme 2 (ACE2) receptor through the spike protein. Here, we develop an engineered, small, stable, and catalytically inactive version of ACE2, termed miniature ACE2 (mACE2), designed to bind the spike protein with high affinity. Employing a magnetic nanoparticle-based assay, we harnessed the strong binding affinity of mACE2 to develop a sensitive and specific platform for the detection or neutralization of SARS-CoV-2. Our findings highlight the potential of engineered mACE2 as a valuable tool in the fight against SARS-CoV-2. The success of developing such a small reagent based on a piecewise molecular design serves as a proof-of-concept approach for the rapid deployment of such agents to diagnose and fight other viral diseases.

The Effect of COVID-19 Vaccination on Outpatient Antibiotic Prescribing in Older Adults: A Self-Controlled Risk-Interval Study.

Coronavirus disease 2019 (COVID-19) vaccination has been associated with reduced outpatient antibiotic prescribing among older adults with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We assessed the impact of COVID-19 vaccination on outpatient antibiotic prescribing in the broader population of older adults, regardless of SARS-CoV-2 infection status. We included adults aged ≥65 years who received their first, second, and/or third COVID-19 vaccine dose from December 2020 to December 2022. We used a self-controlled risk-interval design and included cases who received an antibiotic prescription 2-6 weeks before vaccination (pre-vaccination or control interval) or after vaccination (post-vaccination or risk interval). We used conditional logistic regression to estimate the odds of being prescribed (1) any antibiotic, (2) a typical "respiratory" infection antibiotic, or (3) a typical "urinary tract" infection antibiotic (negative control) in the post-vaccination interval versus the pre-vaccination interval. We accounted for temporal changes in antibiotic prescribing using background monthly antibiotic prescribing counts. 469 923 vaccine doses met inclusion criteria. The odds of receiving any antibiotic or a respiratory antibiotic prescription were lower in the post-vaccination versus pre-vaccination interval (aOR, .973; 95% CI, .968-.978; aOR, .961; 95% CI, .953-.968, respectively). There was no association between vaccination and urinary antibiotic prescriptions (aOR, .996; 95% CI, .987-1.006). Periods with high (>10%) versus low (<5%) SARS-CoV-2 test positivity demonstrated greater reductions in antibiotic prescribing (aOR, .875; 95% CI, .845-.905; aOR, .996; 95% CI, .989-1.003, respectively). COVID-19 vaccination was associated with reduced outpatient antibiotic prescribing in older adults, especially during periods of high SARS-CoV-2 circulation.

Safety, tolerability, and pharmacokinetics of the novel RdRp inhibitor SHEN26 against SARS-CoV-2: a randomized, placebo-controlled, double-blind phase I study in healthy subjects

ABSTRACT Background SHEN26, an oral broad-spectrum antiviral drug, possesses potent preclinical activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has a favorable safety profile. Methods We report safety, tolerability, and pharmacokinetic data from a randomized, double-blind, placebo-controlled phase I study of SHEN26. Eighty-six healthy subjects were enrolled in the three studies: a single ascending-dose study (SAD), a multiple ascending-dose study (MAD), and a food-effect study (FE). Results In the SAD trial, the maximum observed plasma concentration (Cmax) and area under the curve (AUC) of the SHEN26 rapid metabolite SHEN26-69-0 increased approximately dose-proportionally in the 50–400 mg fasting dose range. In the 800 mg dose group, standard meals increased the Cmax and AUC of SHEN26-69-0. In the MAD trial, the accumulation ratios of Cmax and AUC indicated slight accumulation upon repeated SHEN26 dosing. In the FE trial, a high-fat meal prolonged the time to maximum plasma concentration (Tmax) and increased the Cmax and AUC of SHEN26-69-0 compared with fasting administration. Most treatment-related adverse events were mild and resolved without treatment. Conclusion SHEN26 demonstrated satisfactory safety and tolerability in healthy subjects, which supports the continued study of SHEN26 against SARS-CoV-2. Trial Registration The trial is registered in ClinicalTrials.gov (CT. gov identifier: NCT05504746).

ELANE rs17223045C/T and rs3761007G/A variants: Protective factors against COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for causing coronavirus disease 2019 (COVID-19). The development and severity of this infectious disease is influenced by a combination of environmental and genetic factors. Angiotensin-converting enzyme 2 (ACE2) facilitates SARS-CoV-2 entry into human cells, with transmembrane serine protease 2 (TMPRSS2) playing a crucial role in S protein priming. Other proteases, such as cathepsin L and elastase, neutrophil-expressed (ELANE), have the capability to prime the S protein and contribute to SARS-CoV-2 infection. ELANE variants have not been previously examined in COVID-19 patients. We aimed to assess the association of single nucleotide variants (SNVs) within ELANE with COVID-19 and biochemical markers. The study included 319 SARS-CoV-2-infected patients and 288 controls. Genotyping of ELANE rs17216663C/T (Pro257Leu), rs17223045C/T (As1n30Asn), and rs3761007G/A was conducted using a 5'-nuclease allelic discrimination assay (TaqMan assay). Our findings indicate that ELANE rs17223045C/T (C vs T: odds ratio [OR] 0.08, P = 0.005, and CC vs CT: OR 0.08, P = 0.005) and rs3761007G/A (G vs A: OR 0.38, P = 0.009, and GG vs GA: OR 0.40, P = 0.008) confer protection against COVID-19. However, these variants were not associated with biochemical markers. In conclusion, our data suggests that ELANE rs17223045C/T and rs3761007G/A SNVs may play a protective role against COVID-19.