- Robotic-inspired approach to multi-domain membrane receptor conformation space: theory and SARS-CoV-2 spike protein case study -
The spike protein of SARS-CoV-2 is a highly flexible membrane receptor that triggers the translocation of the virus into cells by attaching to the human receptors. Like other type I membrane receptors, this protein has several extracellular domains connected by flexible hinges. The presence of these hinges results in high flexibility, which consequently results in challenges in defining the conformation of the protein. Here, We developed a new method to define the conformational space based on a few variables inspired by the robotic field's methods to determine a robotic arm's forward kinematics. Using newly performed atomistic molecular dynamics (MD) simulations and publicly available data, we found that the Denavit-Hartenberg (DH) parameters can reliably show the changes in the local conformation. Furthermore, the rotational and translational components of the homogenous transformation matrix constructed based on the DH parameters can identify the changes in the global conformation of the spike and also differentiate between the conformation with a similar position of the spike head, which other types of parameters, such as spherical coordinates, fail to distinguish between such conformations. Finally, the new method will be beneficial for looking at the conformational heterogeneity in all other type I membrane receptors.
- ViRNN: A Deep Learning Model for Viral Host Prediction -
Viral outbreaks are on the rise in the world, with the current outbreak of COVID-19 being among one of the worst thus far. Many of these outbreaks were the result of zoonotic transfer between species, and thus understanding and predicting the host of a virus is very important. With the rise of sequencing technologies it is becoming increasingly easy to sequence the full genomes of viruses, databases of publicly available viral genomes are widely available. We utilize a convolutional and recurrent neural network architecture (ViRNN) to predict the hosts for the Coronaviridae family (Coronaviruses) amongst the eleven most common hosts of this family. Our architecture performed with an overall accuracy of 90.55% on our test dataset, with a micro-average AUC-PR of 0.97. Performance was variable per host. ViRNN outperformed previously published methods like k-nearest neighbors and support vector machines, as well as previously published deep learning based methods. Saliency maps based on integrated gradients revealed a number of proteins in the viral genome that may be important interactions determining viral infection in hosts. Overall, this method provides an adaptable classifier capable of predicting host species from viral genomic sequence with high accuracy.
- Synthetic coevolution reveals adaptive mutational trajectories of neutralizing antibodies and SARS-CoV-2 -
The Covid-19 pandemic showcases a coevolutionary race between the human immune system and SARS-CoV-2, mirroring the Red Queen hypothesis of evolutionary biology. The immune system generates neutralizing antibodies targeting the SARS-CoV-2 spike protein's receptor binding domain (RBD), crucial for host cell invasion, while the virus evolves to evade antibody recognition. Here, we establish a synthetic coevolution system combining high-throughput screening of antibody and RBD variant libraries with protein mutagenesis, surface display, and deep sequencing. Additionally, we train a protein language machine learning model that predicts antibody escape to RBD variants. Synthetic coevolution reveals antagonistic and compensatory mutational trajectories of neutralizing antibodies and SARS-CoV-2 variants, enhancing the understanding of this evolutionary conflict.
- Emotional distress and affective knowledge representation one year after the Covid-19 outbreak -
This study examines whether the detrimental effects of the COVID-19 pandemic on the affectivity of the population extend one year after the outbreak. In an online-mobile session, participants completed surveys (i.e. demographic characteristics, positive-negative affectivity, interoceptive awareness) and a similarity judgment task of triplets of emotional concepts, from which we derived 2D maps of their affective knowledge representation. Compared with pre-pandemic data derived from a comparable population, we report three main findings. First, we observed enhanced negative affectivity during the pandemic, but no changes in positive affectivity levels. Second, increased self-reported interoceptive awareness compared to pre-pandemic data, with greater attention to bodily sensations and adaptive aspects of interoceptive sensitivity. Furthermore, female participants reported higher scores than males on the questionnaire subscales of Emotional Awareness and Attention Regulation. Third, the effect of pandemic-related conditions is also apparent in the mental organization of emotional concepts, especially for female participants (i.e., reduced coherence in the organization of the concepts along the arousal dimension and more misclassification of concepts based on arousal) and participants who did not perform physical activity (a collapse of the arousal dimension). Some of the effects of the pandemic, thus, persist about a year after the outbreak. These results advise providing programs of psychological and emotional assistance throughout the pandemic beyond the outbreak, and that age-dependent gender differences should be accounted for to define tailored interventions. Physical activity might relieve pandemic-related stressors, so it should be promoted during particularly stressful periods for the population.
- Nanoscale cellular organization of viral RNA and proteins in SARS-CoV-2 replication organelles -
The SARS-CoV-2 viral infection transforms host cells and produces special organelles in many ways, and we focus on the replication organelle where the replication of viral genomic RNA (vgRNA) occurs. To date, the precise cellular localization of key RNA molecules and replication intermediates has been elusive in electron microscopy studies. We use super-resolution fluorescence microscopy and specific labeling to reveal the nanoscopic organization of replication organelles that contain vgRNA clusters along with viral double-stranded RNA (dsRNA) clusters and the replication enzyme, encapsulated by membranes derived from the host endoplasmic reticulum (ER). We show that the replication organelles are organized differently at early and late stages of infection. Surprisingly, vgRNA accumulates into distinct globular clusters in the cytoplasmic perinuclear region, which grow and accommodate more vgRNA molecules as infection time increases. The localization of ER labels and nsp3 (a component of the double-membrane vesicle, DMV) at the periphery of the vgRNA clusters suggests that replication organelles are enclosed by DMVs at early infection stages which then merge into vesicle packets as infection progresses. Precise co-imaging of the nanoscale cellular organization of vgRNA, dsRNA, and viral proteins in replication organelles of SARS-CoV-2 may inform therapeutic approaches that target viral replication and associated processes.
- A mechanism that transduces lysosomal damage signals to stress granule formation for cell survival -
Lysosomal damage poses a significant threat to cell survival. Our previous work has reported that lysosomal damage induces stress granule (SG) formation. However, the importance of SG formation in determining cell fate and the precise mechanisms through which lysosomal damage triggers SG formation remains unclear. Here, we show that SG formation is initiated via a novel calcium-dependent pathway and plays a protective role in promoting cell survival in response to lysosomal damage. Mechanistically, we demonstrate that during lysosomal damage, ALIX, a calcium-activated protein, transduces lysosomal damage signals by sensing calcium leakage to induce SG formation by controlling the phosphorylation of eIF2. ALIX modulates eIF2 phosphorylation by regulating the association between PKR and its activator PACT, with galectin-3 exerting a negative effect on this process. We also found this regulatory event of SG formation occur on damaged lysosomes. Collectively, these investigations reveal novel insights into the precise regulation of SG formation triggered by lysosomal damage, and shed light on the interaction between damaged lysosomes and SGs. Importantly, SG formation is significant for promoting cell survival in the physiological context of lysosomal damage inflicted by SARS-CoV-2 ORF3a, adenovirus infection, Malaria hemozoin, proteopathic tau as well as environmental hazard silica.
- Aversive personality and COVID-19: A first review and meta-analysis -
The Coronavirus Disease 2019 (COVID-19) has strongly affected individuals and societies worldwide. In this review and meta-analysis, we investigated how aversive personality traits—i.e., relatively stable antisocial personality characteristics—related to how individuals perceived, evaluated, and responded to the COVID-19 pandemic. Across 34 studies with overall 26,780 participants, we found that people with higher scores in aversive personality traits were less likely to perceive guidelines and restrictions to curb the spread of the virus as protective (p̂ = -.11), to engage in health behaviors related to COVID-19 (p̂ = -.16), and to engage in non-health related prosocial behavior related to COVID-19 (p̂ = -.14). We found no consistent relation between aversive personality and negative affect regarding the pandemic. The results thus indicate the importance of aversive personality traits in understanding individual differences with regard to COVID-19.
- Information about herd immunity through vaccination and empathy promote COVID-19 vaccination intentions -
Objective: An effective vaccine against COVID-19 is a desired solution to curb the spread of the disease. However, vaccine hesitancy might hinder high uptake rates and thus undermine efforts to eliminate COVID-19 once an effective vaccine became available. The present contribution addresses this issue by examining two ways of increasing the intention to get vaccinated against COVID-19. Methods: Two pre-registered online studies were conducted (N = 2,315 participants from the UK) in which knowledge about and beliefs in herd immunity through vaccination, as well as empathy for those most vulnerable to the virus, were either measured (Study 1) or manipulated (Study 2). As a dependent variable, individuals’ self-reported vaccination intention once a vaccine against COVID-19 became available was assessed. Results: In Study 1 (N = 310), the intention to get vaccinated against COVID-19 was correlated with knowledge about and belief in herd immunity (r = .58, p < .001), as well as with empathy for those most vulnerable to the virus (r = .26, p < .001). In Study 2 (N = 2,005), information about herd immunity (Cohen’s d = 0.13, p = .003) and empathy (Cohen’s d = 0.22, p < .001) independently promoted vaccination intention. Conclusions: The motivation to get vaccinated against COVID-19 was related to and could be causally promoted by both mere information about herd immunity and by empathy. As such, the present research provides a better understanding of the intention to get vaccinated against COVID-19.
- The emotional path to action: Empathy promotes physical distancing and wearing of face masks during the COVID-19 pandemic -
The COVID-19 pandemic presents a major challenge to societies all over the globe. To curb the spread of the disease, two measures implemented in many countries are minimizing close contact between people (“physical distancing”) and wearing face masks. In the present research, we tested the idea that physical distancing and wearing face masks can be the result of a genuine prosocial emotion—empathy for those most vulnerable to the virus. In four pre-registered studies (total N = 3,718‬, Western population), we show that (i) empathy is indeed a basic motivation for physical distancing and wearing face masks, and (ii) inducing empathy for those most vulnerable to the virus promotes the motivation to adhere to these measures (whereas providing mere information about its importance is not). In sum, the present research provides a better understanding of the promoting factors underlying the willingness to follow two important measures during the COVID-19 pandemic.
- Abolished frameshifting for predicted structure-stabilizing SARS-CoV-2 mutants: Implications to alternative conformations and their statistical structural analyses -
The SARS-CoV-2 frameshifting element (FSE) has been intensely studied and explored as a therapeutic target for coronavirus diseases including COVID-19. Besides the intriguing virology, this small RNA is known to adopt many length-dependent conformations, as verified by multiple experimental and computational approaches. However, the role these alternative conformations play in the frameshifting mechanism and how to quantify this structural abundance has been an ongoing challenge. Here, we show by DMS and dual-luciferase functional assays that previously predicted FSE mutants (using the RAG graph theory approach) suppress structural transitions and abolish frameshifting. Furthermore, correlated mutation analysis of DMS data by three programs (DREEM, DRACO, and DANCE-MaP) reveals important differences in their estimation of specific RNA conformations, suggesting caution in the interpretation of such complex conformational landscapes. Overall, the abolished frameshifting in three different mutants confirms that all alternative conformations play a role in the pathways of ribosomal transition.
- Broad-Spectrum Coronavirus Inhibitors Discovered by Modeling Viral Fusion Dynamics -
Broad-spectrum therapeutics capable of inhibiting SARS-CoV-2, its variants, and related coronaviruses hold promise in curbing the spread of COVID-19 and averting future pandemics. Here, we employed a multidisciplinary approach that included molecular dynamics simulation (MDS) and artificial intelligence (AI)-based docking predictions to identify potent inhibitors that target a conserved region within the SARS-CoV-2 spike protein that mediates membrane fusion by undergoing large-scale mechanical rearrangements. In silico binding screens honed in on this region, leading to the discovery of FDA-approved drugs and novel molecules predicted to disrupt spike protein conformational changes. These compounds significantly inhibited SARS-CoV-2 infection and blocked the entry of spike protein-bearing pseudotyped , {beta}, {gamma}, {delta} variants as well as SARS-CoV and MERS-CoV in cultured human ACE2-expressing cells. The optimized lead compound significantly inhibited SARS-CoV2 infection in mice when administered orally.
- Enhanced mucosal B- and T-cell responses against SARS-CoV-2 after heterologous intramuscular mRNA prime/intranasal protein boost vaccination with a combination adjuvant. -
Current COVID-19 mRNA vaccines delivered intramuscularly (IM) induce effective systemic immunity, but with suboptimal immunity at mucosal sites, limiting their ability to impart sterilizing immunity. There is strong interest in rerouting immune responses induced in the periphery by parenteral vaccination to the portal entry site of respiratory viruses, such as SARS-CoV-2, by mucosal vaccination. We previously demonstrated the combination adjuvant, NE/IVT, consisting of a nanoemulsion (NE) and an RNA-based RIG-I agonist (IVT) induces potent systemic and mucosal immune responses in protein-based SARS-CoV-2 vaccines administered intranasally (IN). Herein, we demonstrate priming IM with mRNA followed by heterologous IN boosting with NE/IVT adjuvanted recombinant antigen induces strong mucosal and systemic antibody responses and enhances antigen-specific T cell responses in mucosa-draining lymph nodes compared to IM/IM and IN/IN prime/boost regimens. While all regimens induced cross-neutralizing antibodies against divergent variants and sterilizing immunity in the lungs of challenged mice, mucosal vaccination, either as homologous prime/boost or heterologous IN boost after IM mRNA prime was required to impart sterilizing immunity in the upper respiratory tract. Our data demonstrate the benefit of hybrid regimens whereby strong immune responses primed via IM vaccination are rerouted by IN vaccination to mucosal sites to provide optimal protection to SARS-CoV-2.
- Development and Application of Decontamination Methods for the Re-Use of Laboratory Grade Plastic Pipette Tips -
During the SARS-CoV-2 pandemic, a need for methods to decontaminate and reuse personal protective equipment (PPE) and medical plastics became a priority. In this investigation we aimed to develop a contamination evaluation protocol for laboratory pipette tips, after decontamination. Decontamination methods tested in this study included cleaning with a common laboratory detergent (2.5% Alconox(R) solution followed with steam decontamination), exposure of ozone vapor at 250 and 14400 PPM * minute, and exposure to cold atmospheric plasma (CAP). All tips (control and experimental groups) were introduced to the methods described, while tips exposed to DNA extracts of Aeromonas hydrophila (ATCC-23211) were assessed for experimental groups. Decontamination was determined by turnover ratio and log reduction in detectable genomic material on the contaminated products using real-time quantitative PCR (qPCR) assay. Our results showed, cleaning tips with lab detergents along with steam decontamination removed genetic material, resulting in the highest log reduction, compared with ozone or CAP treatments. Detergent/washing methods showed the highest turnover ratio (95.9 %) and log reduction (5.943). However, the excessive residue (post- cleaning) on the plastic, within inner filters, and tip boxes suggested that washing with lab detergents was not favorable for reuse. Ozone vapor at 14400 PPM * minutes showed the second highest turnover ratio (98.4 %) and log reduction (4.511). CAP exposure with tips inverted (the tip end exposed closer to the plasma flame) for 1 minute showed a turnover ratio of (68.3 %) and log reduction (4.002). Relatively, lower turnover ratio and log reduction of CAP could be attributed to development/optimization of treatment conditions, including increases in exposure time and relative to tip positioning.
- Human long noncoding RNA, VILMIR, is induced by major respiratory viral infections and modulates the host interferon response -
Long noncoding RNAs (lncRNAs) are a newer class of noncoding transcripts identified as key regulators of biological processes. Here we aimed to identify novel lncRNA targets that play critical roles in major human respiratory viral infections by systematically mining large-scale transcriptomic datasets. Using bulk RNA-sequencing (RNA-seq) analysis, we identified a previously uncharacterized lncRNA, named virus inducible lncRNA modulator of interferon response (VILMIR), that was consistently upregulated after in vitro influenza infection across multiple human epithelial cell lines and influenza A virus subtypes. VILMIR was also upregulated after SARS-CoV-2 and RSV infections in vitro. We experimentally confirmed the response of VILMIR to influenza infection and interferon-beta (IFN-{beta}) treatment in the A549 human epithelial cell line and found the expression of VILMIR was robustly induced by IFN-{beta} treatment in a dose and time-specific manner. Single cell RNA-seq analysis of bronchoalveolar lavage fluid (BALF) samples from COVID-19 patients uncovered that VILMIR was upregulated across various cell types including at least five immune cells. The upregulation of VILMIR in immune cells was further confirmed in the human T cell and monocyte cell lines, SUP-T1 and THP-1, after IFN-{beta} treatment. Finally, we found that knockdown of VILMIR expression reduced the magnitude of host transcriptional responses to IFN-{beta} treatment in A549 cells. Together, our results show that VILMIR is a novel interferon-stimulated gene (ISG) that regulates the host interferon response and may be a potential therapeutic target for human respiratory viral infections upon further mechanistic investigation.
- Inference of epidemic dynamics in the COVID-19 era and beyond -
The COVID-19 pandemic demonstrated the key role that epidemiology and modelling play in analysing infectious threats and supporting decision making in real-time. Motivated by the unprecedented volume and breadth of data generated during the pandemic, we review new analytic opportunities and methodological developments available to address questions that emerge during a major modern epidemic. Following the broad chronology of insights required - from understanding initial dynamics to retrospective evaluation of interventions, we describe the theoretical foundations of each approach and the underlying intuition. Through a series of case studies, we illustrate real life applications, and discuss implications for future work.
Quantitating SARS-CoV-2 Neutralizing Antibodies from Human Dried Blood Spots - CONCLUSION: SARS-CoV-2 neutralizing titers can be derived with confidence from DBS eluates, thereby opening the door to the use of these biospecimens for the analysis of vulnerable populations and normally hard to reach communities.
Lipid Nanoparticle-Based Inhibitors for SARS-CoV-2 Host Cell Infection - CONCLUSION: Both LNP-Trap and LNP-Trim formulations were able to safely and effectively inhibit SARS-CoV-2 pseudoviral infection in airway epithelial cells. These studies provide proof-of-principle for a localized treatment approach for SARS-CoV-2 in the upper airway.
Transcriptional-profile changes in the medial geniculate body after noise-induced tinnitus - Tinnitus is a disturbing condition defined as the occurrence of acoustic hallucinations with no actual sound. Although the mechanisms underlying tinnitus have been explored extensively, the pathophysiology of the disease is not completely understood. Moreover, genes and potential treatment targets related to auditory hallucinations remain unknown. In this study, we examined transcriptional-profile changes in the medial geniculate body after noise-induced tinnitus in rats by performing RNA…
Acceptance, safety, and immunogenicity of a booster dose of inactivated SARS-CoV-2 vaccine in patients with primary biliary cholangitis - Inactivated coronavirus disease 2019 (COVID-19) vaccines showed impaired immunogenicity in some autoimmune diseases, but it remains unclear in primary biliary cholangitis (PBC). This study aimed to explore the antibody response to the inactivated COVID-19 vaccine in individuals with PBC, as well as to evaluate coverage, safety, and attitudes toward the COVID-19 vaccine among them. Two cohorts of patients with PBC were enrolled in this study. One cohort was arranged to evaluate the immunogenicity…
Vgamma9Vdelta2 T-cells are potent inhibitors of SARS-CoV-2 replication and represent effector phenotypes in COVID-19 patients - Vγ9Vδ2 T-cells play a key role in the innate immune response to viral infections through butyrophilin (BTN)-3A. Here, we reported that blood Vγ9Vδ2 T-cells decreased in clinically mild COVID-19 compared to healthy volunteers (HV), and was maintained up to 28-days and in the recovery period. Terminally differentiated Vγ9Vδ2 T-cells tend to be enriched on the day of diagnosis, 28-days after and during the recovery period. These cells showed cytotoxic and inflammatory activities following…
Isolation, characterization and SARS-CoV-2 3CL protease inhibitory activity of a new methylsulfinyl-butanyl derivative from Raphani Semen - A new compound named raphanised A (1), along with two known methylsulfinyl -butanyl derivatives (2-3) and seven known indole derivatives (4-10), were isolated from the Raphani Semen. Among the indole derivatives, 5 was identified as a new natural product, and 4, 6, 7, 8, 9, 10 were isolated from the genus of Raphanus for the first time. Their structures were elucidated based on the NMR and HR-EI-MS analysis. Additionally, the inhibitory activity of methylsulfinyl-butanyl derivatives 1-3 on SARS…
CD151 Maintains Endolysosomal Protein Quality to Inhibit Vascular Inflammation - CONCLUSIONS: Distinct from its canonical function in strengthening cell adhesion at cell surface, CD151 maintains endolysosome function by sustaining VCP/p97-mediated protein unfolding and turnover. By supporting protein quality control and protein degradation, CD151 prevents proteins from (1) buildup in endolysosomes and (2) discharge through exosomes, to limit vascular inflammation. Also, our study conceptualizes that balance between degradation and discharge of proteins in endothelial cells…
Comparative evaluation of tocilizumab and itolizumab for treatment of severe COVID-19 in India: a retrospective cohort study - CONCLUSIONS: The CI with itolizumab is similar to tocilizumab. Better oxygenation can be achieved with itolizumab and it can be a substitute for tocilizumab in managing severe COVID-19.
Synthesis and pharmacodynamic evaluation of Dihydropteridone derivatives against PDCoV in vivo and in vitro - Porcine Delta Coronavirus (PDCoV) infection can induce serious dehydration, diarrhea and even death of piglets, which has caused huge losses to the breeding industry. PDCoV has been reported to have the potential for cross species transmission, and even reports of infecting humans have emerged. At present, there are still no effective prevention and control measures for PDCoV. In this study, we have designed and synthesized a series of unreported Dihydropteridone derivatives. All of these…
New conjugates based on N4-hydroxycytidine with more potent antiviral efficacy in vitro than EIDD-2801 against SARS-CoV-2 and other human coronaviruses - The spread of COVID-19 continues due to genetic variation in SARS-CoV-2. Highly mutated variants of SARS-CoV-2 have an increased transmissibility and immune evasion. Due to the emergence of various new variants of the virus, there is an urgent need to develop broadly effective specific drugs for therapeutic strategies for the prevention and treatment of COVID-19. Molnupiravir (EIDD-2801, MK-4482), is an orally bioavailable ribonucleoside analogue of β-D-N4-hydroxycytidine (NHC), has demonstrated…
Biological responses in Danio rerio by the disinfectant SDBS in SARS-CoV-2 pandemic - The use of disinfectants, such as Sodium Dodecylbenzene Sulfonic acid salt (SDBS), has grown since the SARS-CoV-2 pandemic, with environmentally unknown consequences. The present study analyzed SDBS effects in the fish species Danio rerio, using a combination of biomarkers. Our data reported that larvae had their total locomotor activity increased when exposed to 1mg/L of SDBS, but this parameter was decreased in fish exposed to 5mg/L. A significant increment of erratic movements was reported in…
Preclinical evaluation of the SARS-CoV-2 M(pro) inhibitor RAY1216 shows improved pharmacokinetics compared with nirmatrelvir - Although vaccines are available for SARS-CoV-2, antiviral drugs such as nirmatrelvir are still needed, particularly for individuals in whom vaccines are less effective, such as the immunocompromised, to prevent severe COVID-19. Here we report an α-ketoamide-based peptidomimetic inhibitor of the SARS-CoV-2 main protease (M^(pro)), designated RAY1216. Enzyme inhibition kinetic analysis shows that RAY1216 has an inhibition constant of 8.4 nM and suggests that it dissociates about 12 times slower…
A new DNA aptamer which binds to SARS-CoV-2 spike protein and reduces pro-inflammatory response - COVID-19 caused by SARS-CoV-2 spread rapidly around the world, endangering the health of people globally. The SARS-CoV-2 spike protein initiates entry into target cells by binding to human angiotensin-converting enzyme 2 (ACE2). In this study, we developed DNA aptamers that specifically bind to the SARS-CoV-2 spike protein, thereby inhibiting its binding to ACE2. DNA aptamers are small nucleic acid fragments with random structures that selectively bind to various target molecules. We identified…
Protective mucosal SARS-CoV-2 antibodies in the majority of the general population in the Netherlands - Antibodies to SARS-CoV-2 at mucosal surfaces of the respiratory tract are understood to contribute to protection against SARS-CoV-2 infection. We aimed to describe the prevalence, levels and functionality of mucosal antibodies in the general Dutch population. Nasal samples were collected from 778 randomly selected participants, 1-90 years of age, nested within the nationwide prospective SARS-CoV-2 PIENTER corona serosurvey in the Netherlands. Spike-specific IgG was detected in nasal samples of…
Intranasal boosting with RBD-HR protein vaccine elicits robust mucosal and systemic immune responses - The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has decreased the efficacy of SARS-CoV-2 vaccines in containing coronavirus disease 2019 (COVID-19) over time, and booster vaccination strategies are urgently necessitated to achieve sufficient protection. Intranasal immunization can improve mucosal immunity, offering protection against the infection and sustaining the spread of SARS-CoV-2. In this study, an intranasal booster of the RBD-HR vaccine after two…