Exploring the potential mechanisms of Danshen against COVID-19 via network pharmacology analysis and molecular docking.

Danshen, a prominent herb in traditional Chinese medicine (TCM), is known for its potential to enhance physiological functions such as blood circulation, immune response, and resolve blood stasis. Despite the effectiveness of COVID-19 vaccination efforts, some individuals still face severe complications post-infection, including pulmonary fibrosis, myocarditis arrhythmias and stroke. This study employs a network pharmacology and molecular docking approach to investigate the potential mechanisms underlying the therapeutic effects of candidate components and targets from Danshen in the treatment of complications in COVID-19. Candidate components and targets from Danshen were extracted from the TCMSP Database, while COVID-19-related targets were obtained from Genecards. Venn diagram analysis identified common targets. A Protein-Protein interaction (PPI) network and gene enrichment analysis elucidated potential therapeutic mechanisms. Molecular docking evaluated interactions between core targets and candidate components, followed by molecular dynamics simulations to assess stability. We identified 59 potential candidate components and 123 targets in Danshen for COVID-19 treatment. PPI analysis revealed 12 core targets, and gene enrichment analysis highlighted modulated pathways. Molecular docking showed favorable interactions, with molecular dynamics simulations indicating high stability of key complexes. Receiver operating characteristic (ROC) curves validated the docking protocol. Our study unveils candidate compounds, core targets, and molecular mechanisms of Danshen in COVID-19 treatment. These findings provide a scientific foundation for further research and potential development of therapeutic drugs.

Risk factors and multi-pathogen infections in kidney transplant recipients with omicron variant pneumonia: a retrospective analysis.

BACKGROUND: Kidney transplant recipients (KTRs) are at an elevated risk of progressing to severe infections upon contracting COVID-19. We conducted a study on risk factors and multi-pathogen infections in KTRs with SARS-CoV-2 Omicron variant. METHODS: KTRs were subjected to a thorough etiological evaluation. Whenever feasible, they were also provided with bronchoscopy and bronchoalveolar lavage to enable metagenomic next-generation sequencing (mNGS), ideally within a 48-hour window post-admission. We performed a retrospective analysis for pathogens and risk factors of KTRs with the COVID-19 virus variant Omicron. RESULTS: We included thirty patients in our study, with sixteen exhibiting single infection of COVID-19 and fourteen experiencing co-infections, predominantly with Pneumocystis jirovecii. Notably, patients with severe cases demonstrated significantly elevated levels of C-reactive protein (CRP) and interleukin-6 compared to those with moderate cases (P < 0.05). Furthermore, individuals whose conditions progressed had markedly higher baseline serum creatinine levels than those without such progression (P < 0.05). The presence of heart failure, acute exacerbation of renal dysfunction, and a history of opportunistic infections were significantly associated with a higher likelihood of deterioration and hospital admission due to the SARS-CoV-2 Omicron variant, as compared to the control group (P < 0.05). In subsequent follow-up analysis, the all-cause rehospitalization rate was observed to be 21.4%, with Pneumocystis jirovecii infection accounting for half of these cases. CONCLUSION: Among KTRs, a significant coinfection rate of 47% was observed, with Pneumocystis jirovecii emerging as the predominant pathogen in these cases. The development of heart failure, acute exacerbation of chronic renal dysfunction, and a prior history of opportunistic infections have been identified as potential risk factors that may contribute to clinical deterioration in KTRs. Additionally, Pneumocystis jirovecii infection has been established as a critical factor influencing the rate of all-cause rehospitalization within this patient population.

Epidemiological and clinical characteristics of hospitalized human metapneumovirus patients in Israel, 2015-2021: A retrospective cohort study.

This study evaluated the epidemiological and clinical characteristics of human metapneumovirus (hMPV) infection among hospitalized patients with acute respiratory infections during 2015-2021 and assessed the impact of the coronavirus disease 2019 pandemic on hMPV infection. A single-center, retrospective cohort study was performed, including pediatric and adult patients with laboratory-confirmed hMPV. Of a total of 990 patients, 253 (25.6%), 105 (10.6%), 121 (12.2%), and 511 (51.6%) belonged to age groups 0-2, 3-17, 18-59, and ≥60 years, respectively. The highest percentage (23.0%) of patients were hospitalized during 2019 and the lowest (4.7%) during 2020. Patients < 18 years experienced high rates of comorbidities (immunodeficiencies: 14.4% and malignancies: 29.9%). Here, 37/39 (94.9%) of all bronchiolitis cases were diagnosed in patients < 2 years, whereas more patients in older age groups were diagnosed with pneumonia. A greater proportion of hMPV patients diagnosed with viral coinfection (mostly respiratory syncytial virus and adenovirus) were <18 years. The highest percentages of intensive care unit admissions were recorded among patients < 18 years. Our findings demonstrate that hMPV is an important cause of morbidity in young children and a possibly underestimated cause of morbidity among older adults.

Neuropathological lesions in intravenous BCG-stimulated K18-hACE2 mice challenged with SARS-CoV-2.

In the wake of the COVID-19 pandemic caused by SARS-CoV-2, questions emerged about the potential effects of Bacillus Calmette-Guérin (BCG) vaccine on the immune response to SARS-CoV-2 infection, including the neurodegenerative diseases it may contribute to. To explore this, an experimental study was carried out in BCG-stimulated and non-stimulated k18-hACE2 mice challenged with SARS-CoV-2. Viral loads in tissues determined by RT-qPCR, histopathology in brain and lungs, immunohistochemical study in brain (IHC) as well as mortality rates, clinical signs and plasma inflammatory and coagulation biomarkers were assessed. Our results showed BCG-SARS-CoV-2 challenged mice presented higher viral loads in the brain and an increased frequency of neuroinvasion, with the greatest differences observed between groups at 3-4 days post-infection (dpi). Histopathological examination showed a higher severity of brain lesions in BCG-SARS-CoV-2 challenged mice, mainly consisting of neuroinflammation, increased glial cell population and neuronal degeneration, from 5 dpi onwards. This group also presented higher interstitial pneumonia and vascular thrombosis in lungs (3-4 dpi), BCG-SARS-CoV-2 mice showed higher values for TNF-α and D-dimer values, while iNOS values were higher in SARS-CoV-2 mice at 3-4 dpi. Results presented in this study indicate that BCG stimulation could have intensified the inflammatory and neurodegenerative lesions promoting virus neuroinvasion and dissemination in this experimental model. Although k18-hACE2 mice show higher hACE2 expression and neurodissemination, this study suggests that, although the benefits of BCG on enhancing heterologous protection against pathogens and tumour cells have been broadly demonstrated, potential adverse outcomes due to the non-specific effects of BCG should be considered.

Pleiotropy of positive selection in ancient ACE2 suggests an alternative hypothesis for bat-specific adaptations to host coronaviruses.

Angiotensin-convertingenzyme 2 (ACE2) has dual functions, regulating cardiovascular physiology and serving as the receptor for coronaviruses. Bats, the only true flying mammals and natural viral reservoirs, have evolved positive alterations in traits related to both functions of ACE2. This suggests significant evolutionary changes in ACE2 during bat evolution. To test this hypothesis, we examine the selection pressure in ACE2 along the ancestral branch of all bats (AncBat-ACE2), where powered flight and bat-coronavirus coevolution occurred, and detect a positive selection signature. To assess the functional effects of positive selection, we resurrect AncBat-ACE2 and its mutant (AncBat-ACE2-mut) created by replacing the positively selected sites. Compared to AncBat-ACE2-mut, AncBat-ACE2 exhibits stronger enzymatic activity, enhances mice's performance in exercise fatigue, and shows lower affinity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our findings indicate the functional pleiotropy of positive selection in the ancient ACE2 of bats, providing an alternative hypothesis for the evolutionary origin of bats' defense against coronaviruses.

The prevalence and genotype distribution of human papillomavirus in central Fujian Province during the COVID-19 pandemic.

BACKGROUND: Global human activities were significantly impacted by the emergence of the coronavirus disease 2019 (COVID-19) pandemic caused by the 2019 novel coronavirus. This study aimed to investigate the prevalence and genotype distribution of HPV infection in Central Fujian Province during the pandemic. METHODS: Cervical samples were collected from 21,612 outpatients and 12,664 females who underwent physical examinations and HPV screening at the People's Hospital of Fujian Province in Fuzhou from April 2020 to April 2023. HPV detection and genotyping were conducted using PCR hybridization. RESULTS: The overall HPV infection rate was 16.1% during the COVID-19 pandemic, with the outpatient group exhibiting a greater infection rate (19.0%) than did the healthy group (12.3%). The top five high-risk HPV (HR-HPV) genotypes in both groups were HPV52, HPV53, HPV58, HPV16, and HPV51. Additionally, HPV81 and HPV43 were the two most common low-risk HPV (LR-HPV) genotypes in the patient group, while HPV81 and HPV42 were the two most common LR-HPV genotypes in the healthy group. The highest prevalence of HPV infection was observed in individuals aged ≤ 24 years (28.4%, 95% CI 25.9-30.9), followed by those aged ≥ 55 years (23.6%, 95% CI 21.6-24.7) and other age groups. The prevalence decreased from 23.0% (95% CI 22.4-23.7) in 2018-2019 to 13.8% (95% CI 12.0-15.5) in 2023. CONCLUSION: This study provides valuable insights into the prevalence and genotypes of HPV infection in the female population of Central Fujian Province from 2020 to 2023. The findings indicate that the prevalence of HPV infection in Central Fujian Province remains relatively low compared to the national average. Furthermore, the prevalence of HPV decreased during the COVID-19 pandemic; however, as the pandemic waned, there was potential for an increase in HPV infection rates. Therefore, it is crucial to strengthen HPV screening and vaccination strategies to prevent the potential spread of HPV.

Genetic analysis of SARS-CoV-2 spike gene using Next Generation Sequencing from COVID-19 patients in Erbil/Iraq.

SARS-CoV-2 has been identified by the WHO as a new virus causing mild to severe respiratory illnesses that belong to the Coronavirus family. The virus underwent rapid and continuous changes in the genetic material, especially the S gene, during COVID-19 pandemic and generated a number of new variants announced by WHO in late 2020. Mutations in the S gene have greatly affected virus pathogenesis as the spike protein is responsible for many critical processes. Delta and Omicron variants were studied extensively due to increased mortality and morbidity rates associated with their pandemic waves. This study aimed to analyse the S gene through NGS in an attempt to identify and characterize the circulating variants among the infected population in Erbil/Iraq. Nasopharyngeal and throat swab samples were collected from hospitalized and non-hospitalized patients with COVID-19 symptoms in Erbil City/Iraq from the 1st of November 2021 to the 28th of February 2022. Following confirmation of SARS-CoV-2 infection by RT-PCR, 15 samples were selected and sent to Intergen Lab (Ankara/Turkey) for NGS and analysis. Following analysis and alignment of the received sequences with the Wuhan-Hu-1 strain (wild-type), Delta variant was identified in 13 samples, and Omicron in two. On the whole, different mutation classes have been observed including nonsynonymous, synonymous, non-frameshift deletions and a non-frameshift insertion. The Delta-specific set of mutations, L452R, T478K and P681R, was detected in all Delta isolates. Both Omicron variants appeared to have 35 mutations. D614G variation was conserved in both variants.

[Detection rates and high concentration of herpesvirus (Orthoherpesviridae) DNA in autopsy materials from patients with COVID-19 fatal outcome].

INTRODUCTION: SARS-CoV-2 infection causes immune disorders that create conditions for the reactivation of human herpesviruses (HHVs). However, the estimates of the HHVs effect on the course and outcome of COVID-19 are ambiguous. Аim - to study the possible relationship between the HHV reactivation and the adverse outcome of COVID-19. MATERIALS AND METHODS: Postmortem samples from the brain, liver, spleen, lymph nodes and lungs were obtained from 59 patients treated at the Moscow Infectious Diseases Hospital No.1 in 2021-2023. The group 1 comprised 39 patients with fatal COVID-19; group 2 (comparison group) included 20 patients not infected with SARS-CoV-2 who died from various somatic diseases. HHV DNA and SARS-CoV-2 RNA were determined by PCR. RESULTS: HHV DNA was found in autopsy samples from all patients. In group 1, EBV was most often detected in lymph nodes (94%), HHV-6 in liver (68%), CMV in lymph nodes (18%), HSV in brain (16%), VZV in lung and spleen (3% each). The detection rates of HHVs in both groups was similar. Important differences were found in viral load. In patients with COVID-19, the number of samples containing more than 1,000 copies of HHV DNA per 100,000 cells was 52.4%, in the comparison group - 16.6% (p < 0.002). An association has been established between the reactivation of HSV and HHV-6 and the severity of lung damage. Reactivation of EBV correlated with increased levels of liver enzymes. CONCLUSION: Reactivation of HHVs in patients with fatal COVID-19 was associated with severe lung and liver damages, which indicates a link between HHV reactivation and COVID-19 deaths.

Development, production and characterization of SARS-CoV-2 virus-like particles (Coronaviridae: Orthocoronavirinae: Betacoronavirus: Sarbecovirus).

INTRODUCTION: The COVID-19 pandemic caused by SARS-CoV-2 has created serious health problems worldwide. The most effective way to prevent the occurrence of new epidemic outbreaks is vaccination. One of the modern and effective approaches to vaccine development is the use of virus-like particles (VLPs). The aim of the study is to develop a technology for production of VLP based on recombinant SARS-CoV-2 proteins (E, M, N and S) in insect cells. MATERIALS AND METHODS: Synthetic genes encoding coronavirus proteins E, M, N and S were used. VLP with various surface proteins of strains similar to the Wuhan virus, Delta, Alpha and Omicron were developed and cloned into the pFastBac plasmid. The proteins were synthesized in the baculovirus expression system and assembled into VLP in the portable Trichoplusia ni cell. The presence of insertion in the baculovirus genome was determined by PCR. ELISA and immunoblotting were used to study the antigenic activity of VLP. VLP purification was performed by ultracentrifugation using 20% sucrose. Morphology was assessed using electron microscopy and dynamic light scattering. RESULTS: VLPs consisting of recombinant SARS-CoV-2 proteins (S, M, E and N) were obtained and characterized. The specific binding of antigenic determinants in synthesized VLPs with antibodies to SARS-CoV-2 proteins has been demonstrated. The immunogenic properties of VLPs have been studied. CONCLUSION: The production and purification of recombinant VLPs consisting of full-length SARS-CoV-2 proteins with a universal set of surface antigens have been developed and optimized. Self-assembling particles that mimic the coronavirus virion induce a specific immune response against SARS-CoV-2.

Molecular characterization of SARS-CoV-2 nucleocapsid protein.

Corona Virus Disease 2019 (COVID-19) is a highly prevalent and potent infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Until now, the world is still endeavoring to develop new ways to diagnose and treat COVID-19. At present, the clinical prevention and treatment of COVID-19 mainly targets the spike protein on the surface of SRAS-CoV-2. However, with the continuous emergence of SARS-CoV-2 Variants of concern (VOC), targeting the spike protein therapy shows a high degree of limitation. The Nucleocapsid Protein (N protein) of SARS-CoV-2 is highly conserved in virus evolution and is involved in the key process of viral infection and assembly. It is the most expressed viral structural protein after SARS-CoV-2 infection in humans and has high immunogenicity. Therefore, N protein as the key factor of virus infection and replication in basic research and clinical application has great potential research value. This article reviews the research progress on the structure and biological function of SARS-CoV-2 N protein, the diagnosis and drug research of targeting N protein, in order to promote researchers' further understanding of SARS-CoV-2 N protein, and lay a theoretical foundation for the possible outbreak of new and sudden coronavirus infectious diseases in the future.

Host factors of SARS-CoV-2 in infection, pathogenesis, and long-term effects.

SARS-CoV-2 is the causative virus of the devastating COVID-19 pandemic that results in an unparalleled global health and economic crisis. Despite unprecedented scientific efforts and therapeutic interventions, the fight against COVID-19 continues as the rapid emergence of different SARS-CoV-2 variants of concern and the increasing challenge of long COVID-19, raising a vast demand to understand the pathomechanisms of COVID-19 and its long-term sequelae and develop therapeutic strategies beyond the virus per se. Notably, in addition to the virus itself, the replication cycle of SARS-CoV-2 and clinical severity of COVID-19 is also governed by host factors. In this review, we therefore comprehensively overview the replication cycle and pathogenesis of SARS-CoV-2 from the perspective of host factors and host-virus interactions. We sequentially outline the pathological implications of molecular interactions between host factors and SARS-CoV-2 in multi-organ and multi-system long COVID-19, and summarize current therapeutic strategies and agents targeting host factors for treating these diseases. This knowledge would be key for the identification of new pathophysiological aspects and mechanisms, and the development of actionable therapeutic targets and strategies for tackling COVID-19 and its sequelae.

PDZ2-conjugated-PLGA nanoparticles are tiny heroes in the battle against SARS-CoV-2.

The COVID-19 pandemic caused by SARS-CoV-2 has highlighted the urgent need for innovative antiviral strategies to fight viral infections. Although a substantial part of the overall effort has been directed at the Spike protein to create an effective global vaccination strategy, other proteins have also been examined and identified as possible therapeutic targets. Among them, although initially underestimated, there is the SARS-CoV-2 E-protein, which turned out to be a key factor in viral pathogenesis due to its role in virus budding, assembly and spreading. The C-terminus of E-protein contains a PDZ-binding motif (PBM) that plays a key role in SARS-CoV-2 virulence as it is recognized and bound by the PDZ2 domain of the human tight junction protein ZO-1. The binding between the PDZ2 domain of ZO-1 and the C-terminal portion of SARS-CoV-2 E-protein has been extensively characterized. Our results prompted us to develop a possible adjuvant therapeutic strategy aimed at slowing down or inhibiting virus-mediated pathogenesis. Such innovation consists in the design and synthesis of externally PDZ2-ZO1 functionalized PLGA-based nanoparticles to be used as intracellular decoy. Contrary to conventional strategies, this innovative approach aims to capitalize on the E protein-PDZ2 interaction to prevent virus assembly and replication. In fact, the conjugation of the PDZ2 domain to polymeric nanoparticles increases the affinity toward the E protein effectively creating a "molecular sponge" able to sequester E proteins within the intracellular environment of infected cells. Our in vitro studies on selected cellular models, show that these nanodevices significantly reduce SARS-CoV-2-mediated virulence, emphasizing the importance of exploiting viral-host interactions for therapeutic benefit.

Longitudinal dynamic single-cell mass cytometry analysis of peripheral blood mononuclear cells in COVID-19 patients within 6 months after viral RNA clearance.

This study investigates the longitudinal dynamic changes in immune cells in COVID-19 patients over an extended period after recovery, as well as the interplay between immune cells and antibodies. Leveraging single-cell mass spectrometry, we selected six COVID-19 patients and four healthy controls, dissecting the evolving landscape within six months post-viral RNA clearance, alongside the levels of anti-spike protein antibodies. The T cell immunophenotype ascertained via single-cell mass spectrometry underwent validation through flow cytometry in 37 samples. Our findings illuminate that CD8 + T cells, gamma-delta (gd) T cells, and NK cells witnessed an increase, in contrast to the reduction observed in monocytes, B cells, and double-negative T (DNT) cells over time. The proportion of monocytes remained significantly elevated in COVID-19 patients compared to controls even after six-month. Subpopulation-wise, an upsurge manifested within various T effector memory subsets, CD45RA + T effector memory, gdT, and NK cells, whereas declines marked the populations of DNT, naive and memory B cells, and classical as well as non-classical monocytes. Noteworthy associations surfaced between DNT, gdT, CD4 + T, NK cells, and the anti-S antibody titer. This study reveals the changes in peripheral blood mononuclear cells of COVID-19 patients within 6 months after viral RNA clearance and sheds light on the interactions between immune cells and antibodies. The findings from this research contribute to a better understanding of immune transformations during the recovery from COVID-19 and offer guidance for protective measures against reinfection in the context of viral variants.

Sex-biased immunogenicity of a mucosal subunit vaccine against SARS-CoV-2 in mice.

Introduction: Current vaccines against COVID-19 administered via parenteral route have limited ability to induce mucosal immunity. There is a need for an effective mucosal vaccine to combat SARS-CoV-2 virus replication in the respiratory mucosa. Moreover, sex differences are known to affect systemic antibody responses against vaccines. However, their role in mucosal cellular responses against a vaccine remains unclear and is underappreciated. Methods: We evaluated the mucosal immunogenicity of a booster vaccine regimen that is recombinant protein-based and administered intranasally in mice to explore sex differences in mucosal humoral and cellular responses. Results: Our results showed that vaccinated mice elicited strong systemic antibody (Ab), nasal, and bronchiole alveolar lavage (BAL) IgA responses, and local T cell immune responses in the lung in a sex-biased manner irrespective of mouse genetic background. Monocytes, alveolar macrophages, and CD103+ resident dendritic cells (DCs) in the lungs are correlated with robust mucosal Ab and T cell responses induced by the mucosal vaccine. Discussion: Our findings provide novel insights into optimizing next-generation booster vaccines against SARS-CoV-2 by inducing spike-specific lung T cell responses, as well as optimizing mucosal immunity for other respiratory infections, and a rationale for considering sex differences in future vaccine research and vaccination practice.

Prevalence, under-reporting, and epidemiological surveillance of COVID-19 in the Araguaína City of Brazil.

Asymptomatic and underreported individuals remain a source of coronafig disease 2019 (COVID-19) transmission to others. Data on the prevalence and epidemiological factors influencing transmission are fundamental for establishing control measures, especially in vulnerable regions such as the Amazon. This study aimed to determine the point prevalence and active infection of COVID-19 among the population in Araguaína, a Brazilian city located in the Amazon region, analyzed the socioeconomic and behavioral variables of a statistically representative sample of this population using an epidemiological survey, and identify the viral genomic diversity in the region. During the sixth epidemiological week of 2021 (February 8 to 12), samples of 497 inhabitants of the municipality asymptomatic for respiratory syndromes underwent reverse transcription-quantitative polymerase chain reaction and serological tests (immunoglobulin M and immunoglobulin G). A questionnaire collated data on socioeconomic factors, prevention measures, and health status history. The active infection rate was 6.2%, and the prevalence was 13.5% of the study population. Active infection cases were under-reported; each reported positive case represented 14-28 under-reported cases. Lineages P.2, P.1, and B.1.1 were detected. Working from home was a protective factor against the infection, and clinical signs of fever, dry cough, and loss of taste or smell were associated with testing positive (p <0.05). A descriptive analysis of the indicators revealed that the entire population was susceptible to the disease. Intensified vaccination strategies are required regardless of socioeconomic factors, health conditions, and preventive measures. Implementation of objective, comprehensive, and efficient management tools to minimize the spread of COVID-19 in this municipality can serve as a model for other regions of Brazil.

Choroid plexus defects in Down syndrome brain organoids enhance neurotropism of SARS-CoV-2.

Why individuals with Down syndrome (DS) are more susceptible to SARS-CoV-2-induced neuropathology remains elusive. Choroid plexus (ChP) plays critical roles in barrier function and immune response modulation and expresses the ACE2 receptor and the chromosome 21-encoded TMPRSS2 protease, suggesting its substantial role in establishing SARS-CoV-2 infection in the brain. To explore this, we established brain organoids from DS and isogenic euploid iPSC that consist of a core of functional cortical neurons surrounded by a functional ChP-like epithelium (ChPCOs). DS-ChPCOs recapitulated abnormal DS cortical development and revealed defects in ciliogenesis and epithelial cell polarity in ChP-like epithelium. We then demonstrated that the ChP-like epithelium facilitates infection and replication of SARS-CoV-2 in cortical neurons and that this is increased in DS. Inhibiting TMPRSS2 and furin activity reduced viral replication in DS-ChPCOs to euploid levels. This model enables dissection of the role of ChP in neurotropic virus infection and euploid forebrain development and permits screening of therapeutics for SARS-CoV-2-induced neuropathogenesis.

Epidemic outcomes following government responses to COVID-19: Insights from nearly 100,000 models.

Government responses to COVID-19 are among the most globally impactful events of the 21st century. The extent to which responses-such as school closures-were associated with changes in COVID-19 outcomes remains unsettled. Multiverse analyses offer a systematic approach to testing a large range of models. We used daily data on 16 government responses in 181 countries in 2020-2021, and 4 outcomes-cases, infections, COVID-19 deaths, and all-cause excess deaths-to construct 99,736 analytic models. Among those, 42% suggest outcomes improved following more stringent responses ("helpful"). No subanalysis (e.g. limited to cases as outcome) demonstrated a preponderance of helpful or unhelpful associations. Among the 14 associations with P values < 1 × 10-30, 5 were helpful and 9 unhelpful. In summary, we find no patterns in the overall set of models that suggests a clear relationship between COVID-19 government responses and outcomes. Strong claims about government responses' impacts on COVID-19 may lack empirical support.

Development and application of EpitopeScan, a Python3 toolset for mutation tracking in SARS-CoV-2 immunogenic epitopes.

Introduction: Outbreaks of coronaviruses and especially the recent COVID-19 pandemic emphasize the importance of immunological research in this area to mitigate the effect of future incidents. Bioinformatics approaches are capable of providing multisided insights from virus sequencing data, although currently available software options are not entirely suitable for a specific task of mutation surveillance within immunogenic epitopes of SARS-CoV-2. Method: Here, we describe the development of a mutation tracker, EpitopeScan, a Python3 package with command line and graphical user interface tools facilitating the investigation of the mutation dynamics in SARS-CoV-2 epitopes via analysis of multiple-sequence alignments of genomes over time. We provide an application case by examining three Spike protein-derived immunodominant CD4+ T-cell epitopes restricted by HLA-DRB1*04:01, an allele strongly associated with susceptibility to rheumatoid arthritis (RA). Mutations in these peptides are relevant for immune monitoring of CD4+ T-cell responses against SARS-CoV-2 spike protein in patients with RA. The analysis focused on 2.3 million SARS-CoV-2 genomes sampled in England. Results: We detail cases of epitope conservation over time, partial loss of conservation, and complete divergence from the wild type following the emergence of the N969K Omicron-specific mutation in November 2021. The wild type and the mutated peptide represent potential candidates to monitor variant-specific CD4+ T-cell responses. EpitopeScan is available via GitHub repository https://github.com/Aleksandr-biochem/EpitopeScan.