Accelerated COVID-19 vaccine development: milestones, lessons, and prospects

Gaps in vaccine clinical trials in Africa: A mixed scoping review and bibliometric analysis before, during, and post- COVID-19 pandemic

Africa's participation in vaccine trials has historically been limited, but the COVID-19 pandemic highlighted the need for greater involvement. This study explores vaccine clinical development in Africa, emphasizing its importance for global health security. Using a scoping review and bibliometric analysis, we examined 662 vaccine trials conducted before, during, and after the pandemic. The analysis revealed a significant increase in vaccine trials after 2018 and particularly following the end of the COVID-19 pandemic in May 2023. Most trials focused on viral infections and were single-country studies. Pharmaceutical company sponsors funded most of the earlier trials, with increased government and academic involvement post-2020. Despite progress, challenges remain in the geographic distribution of trials, the number of government-supported studies, and the diversity of conditions studied. Addressing these gaps is crucial to bolstering Africa's role in global vaccine development.

Looking beyond the origin of SARS-CoV-2: Significant strategic aspects during the five-year journey of COVID-19 vaccine development

It has been five years since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and we are also approaching the five-year mark of the COVID-19 pandemic. The vaccine is a significant weapon in combating infectious diseases like SARS-CoV-2. Several vaccines were developed against SARS-CoV-2, and they demonstrated efficacy and safety during these five years. The rapid development of multiple next-generation vaccine candidates in different platforms with very little time is the success story of the vaccine development endeavor. This remarkable success of rapid vaccine development is a new paradigm for fast vaccine development that might help develop infectious diseases and fight against the pandemic. With the completion of five years since the beginning of SARS-CoV-2 origin, we are looking back on the five years and reviewing the milestones, vaccine platforms, animal models, clinical trials, successful collaborations, vaccine safety, real-world effectiveness, and challenges. Lessons learned during these five years will help us respond to public health emergencies and to fight the battle against future pandemics.

Engineered cell membrane-based nano therapies fight infectious diseases

Infectious diseases continue to present significant global public health challenges, with pathogens such as bacteria and viruses posing substantial threats to human health. Conventional therapeutic approaches face several limitations, including the rising prevalence of drug resistance, suboptimal targeting, and adverse side effects, which collectively complicate clinical management. Cell membrane vesicles (MVs), characterized by their natural biocompatibility and outstanding drug delivery capabilities, have emerged as a promising platform for addressing these challenges in the treatment of infectious diseases. To further augment the therapeutic potential of MVs, engineering modifications have been extensively employed to enhance their functionality and efficacy. This review provides a comprehensive overview of the production and modification techniques associated with MVs, emphasizing recent advancements in the development of engineered membrane vesicles (EMVs) as versatile nanoplatforms for combating infectious diseases. Additionally, the clinical prospects and existing challenges of EMVs are critically analyzed, and recommendations are proposed to guide future research and facilitate their clinical translation into practical applications in combating infectious disease.

Predicting immune protection against outcomes of infectious disease from population-level effectiveness data with application to COVID-19

Quantifying the extent to which previous infections and vaccinations confer protection against future infection or disease outcomes is critical to managing the transmission and consequences of infectious diseases. We present a general statistical model for predicting the strength of protection conferred by different immunising exposures (numbers, types, and strains of both vaccines and infections), against multiple outcomes of interest, whilst accounting for immune waning. We predict immune protection against key clinical outcomes: developing symptoms, hospitalisation, and death. We also predict transmission-related outcomes: acquisition of infection and onward transmission in breakthrough infections. These enable quantification of the impact of immunity on population-level transmission dynamics. Our model calibrates the level of immune protection, drawing on both population-level data, such as vaccine effectiveness estimates, and neutralising antibody levels as a correlate of protection. This enables the model to learn realised immunity levels beyond those which can be predicted by antibody kinetics or other correlates alone. We demonstrate an application of the model for SARS-CoV-2, and predict the individual-level protective effectiveness conferred by natural infections with the Delta and the Omicron B.1.1.529 variants, and by the BioNTech-Pfizer (BNT162b2), Oxford-AstraZeneca (ChAdOx1), and 3rd-dose mRNA booster vaccines, against outcomes for both Delta and Omicron. We also demonstrate a use case of the model in late 2021 during the emergence of Omicron, showing how the model can be rapidly updated with emerging epidemiological data on multiple variants in the same population, to infer key immunogenicity and intrinsic transmissibility characteristics of the new variant, before the former can be more directly observed via vaccine effectiveness data. This model provided timely inference on rapidly evolving epidemic situations of significant concern during the early stages of the COVID-19 pandemic. The general nature of the model enables it to be used to support management of a range of infectious diseases.

Rapid development of a registry to accelerate COVID-19 vaccine clinical trials

Response to the SARS-Cov-2 pandemic required the unprecedented, rapid activation of the COVID-19 Prevention Network (CoVPN) representing hundreds of sites conducting vaccine clinical trials. The CoVPN Volunteer Screening Registry (VSR) collected participant information, distributed qualified candidates across sites, and monitored enrollment progress. The system consisted of three web-based interfaces. The Volunteer Questionnaire flowed into a secure database. The Site Portal supported volunteer selection, analytics, and enrollment. The Administrative Portal enabled dynamic analytic reports by geography, clinical trial, and site, including volunteering rates over time. The VSR collected over 650,000 volunteers, serving a key role in the recruitment of diverse participants for multiple Phase 3 clinical trials. Over 47% of the 166,729 volunteers selected for screening represented prioritized groups. The success of the VSR demonstrates how digital tools can be rapidly yet safely integrated into an accelerated clinical trial setting. We summarize the development of the system and lessons learned for pandemic preparedness.

Development of Methods to Produce SARS CoV-2 Virus-Like Particles at Scale

The devastating global toll precipitated by the SARS CoV-2 outbreak and the profound impact of vaccines in stemming that outbreak has established the need for molecular platforms capable of rapidly delivering effective, safe and accessible medical interventions in pandemic preparedness. We describe a simple, efficient and adaptable process to produce SARS CoV-2 virus-like particles (VLPs) that can be readily scaled for manufacturing. A rapid but gentle method of tangential flow filtration using a 100 kDa semi-permeable membrane concentrates and buffer exchanges 0.5 L of SARS CoV-2 VLP containing supernatant into low salt and optimal pH for anion exchange chromatography. VLPs are washed, eluted under high salt, dialyzed into physiological buffer, sterile filtered and aliquoted for storage at -80°C. Purification is completed in less than 2 days. A simple quality control process includes Western blot for coincident detection of Spike, Membrane and Envelope protein as a proxy for intact VLP, ELISA to detect conformationally sensitive Spike using readily available anti-Spike and/or anti-RBD antibodies, and negative stain and immunogold electron microscopy to validate particulate, Spike crowned VLPs. This process to produce SARS CoV-2 VLPs for preclinical studies serves as a roadmap for preparation of more distantly related VLPs for pandemic preparedness.

Key success factors in clinical trial operation of the smallpox vaccine LC16m8 against mpox in Colombia

In 2023, the Japan Institute for Health Security (JIHS) and the Universidad Nacional de Colombia (UNAL) conducted a successful clinical trial of the LC16m8 mpox vaccine in Colombia. The joint Japan-Colombia research team categorized the trial's challenges and success factors into several key operational aspects for analysis. Key success factors were an established database of Colombian human immunodeficiency virus (HIV) patient and pre-exposure prophylaxis (PrEP) population registries, and strong experience with large-scale clinical trials of HIV and COVID-19. In addition, a strong network of infectious disease specialists in Colombia enabled close communication between the study site directors and the research team. This allowed for rapid staffing and training, which was consistent with the study schedule. The outcome of this research identifies key success factors for the immediate implementation of large-scale clinical trials and will contribute to preparedness for future pandemics.

Monitoring Immune Responses to Vaccination: A Focus on Single-Cell Analysis and Associated Challenges

Monitoring the immune response to vaccination encompasses both significant challenges and promising opportunities for scientific advancement. The primary challenge lies in the inherent complexity and interindividual variability of immune responses, influenced by factors including age, genetic background, and prior immunological history. This variability necessitates the development of sophisticated, highly sensitive assays capable of accurately quantifying immune parameters such as antibody titers, T-cell responses, and cytokine profiles. Furthermore, the temporal dynamics of the immune response require comprehensive longitudinal studies to elucidate the durability and quality of vaccine-induced immunity. Challenges of this magnitude pave the way for immunological research advancements and diagnostic methodologies. Cutting-edge monitoring techniques, such as high-throughput sequencing and advanced flow cytometry, enable deeper insights into the mechanistic underpinnings of vaccine efficacy and contribute to the iterative design of more effective vaccines. Additionally, the integration of analytical tools holds the potential to predict immune responses and tailor personalized vaccination strategies. This will be addressed in this review to provide insight for enhancing public health outcomes and fortifying preparedness against future infectious disease threats.

Accelerated vaccine process development by orthogonal protein characterization

The COVID-19 pandemic altered the vaccine development paradigm with accelerated timelines from concept through clinical safety and efficacy. Characterization and release assays for vaccine programs were developed under similar time constraints to support bioprocess development, scaleup and formulation. During the development of these vaccines, SARS-CoV-2 variants of concern (VOCs) emerged requiring integration of additional antigens into the target product profile. Biochemical testing to support the addition of new antigen variants (identity, quantity, antigenicity/potency) needed substantial re-development. Here we present a reversed-phase high-performance liquid-chromatography method for antigen purity with orthogonal identification characterization comprising of Simple Wes and liquid-chromatography tandem mass spectrometry (LC/MS/MS) to support accelerated process development for recombinant protein vaccines. This suite of assays was deployed to support rapid, scientific decision-making enabling the transition from completion of a placebo-controlled dose-ranging Phase 2 study to the start of the global Phase 3 safety and efficacy trial in less than 2 weeks.

College leadership decisions and experiences during the COVID-19 pandemic: an elite interview study

OBJECTIVE

This study at a US Native American-serving Nontribal Institution (NASNTI) deeply analyzed collegiate leadership's responses and experiences during the first year of the COVID-19 pandemic.

PARTICIPANTS

Elite interviews were conducted between April and June 2021 with the college president, provost, dean of student engagement, human resources director, and chief of police. Interviewees were purposively selected due to their positions of authority.

METHODS

Each one-hour interview used a semi-structured guide for standardization and was conducted either virtually or in-person while following COVID-19 protocols. The general inductive method was used to identify nodes and categories within the transcripts.

RESULTS

Six nodes (conceptual domains) and 18 categories were identified. Though there was variability in interviewee emphasis, the respondents described the motivations, drivers, and sentiment behind their decision-making in a transparent way.

CONCLUSIONS

NASNTI leadership reported being able to navigate the pandemic by emphasizing transparency and engaging students, while working alongside the community.

The immunopathogenesis of a cytokine storm: The key mechanisms underlying severe COVID-19

A cytokine storm is marked by excessive pro-inflammatory cytokine release, and has emerged as a key factor in severe COVID-19 cases - making it a critical therapeutic target. However, its pathophysiology was poorly understood, which hindered effective treatment. SARS-CoV-2 initially disrupts angiotensin signalling, promoting inflammation through ACE-2 downregulation. Some patients' immune systems then fail to shift from innate to adaptive immunity, suppressing interferon responses and leading to excessive pyroptosis and neutrophil activation. This amplifies tissue damage and inflammation, creating a pro-inflammatory loop. The result is the disruption of Th1/Th2 and Th17/Treg balances, lymphocyte exhaustion, and extensive blood clotting. Cytokine storm treatments include glucocorticoids to suppress the immune system, monoclonal antibodies to neutralize specific cytokines, and JAK inhibitors to block cytokine receptor signalling. However, the most effective treatment options for mitigating SARS-CoV-2 infection remain vaccines as a preventive measure and antiviral drugs for the early stages of infection. This article synthesizes insights into immune dysregulation in COVID-19, offering a framework to better understand cytokine storms and to improve monitoring, biomarker discovery, and treatment strategies for COVID-19 and other conditions involving cytokine storms.

Modeling the impact of early vaccination in an influenza pandemic in the United States

We modeled the impact of initiating one-dose influenza vaccination at 3 months vs 6 months after declaration of a pandemic over a 1-year timeframe in the US population. Three vaccine effectiveness (VE) and two pandemic severity levels were considered, using an epidemic curve based on typical seasonal influenza epidemics. Vaccination from 3 months with a high, moderate, or low effectiveness vaccine would prevent ~95%, 84%, or 38% deaths post-vaccination, respectively, compared with 21%, 18%, and 8%, respectively following vaccination at 6 months, irrespective of pandemic severity. While the pandemic curve would not be flattened from vaccination from 6 months, a moderate/high effectiveness vaccine could flatten the curve if administered from 3 months. Overall, speed of initiating a vaccination campaign is more important than VE in reducing the health impacts of an influenza pandemic. Preparedness strategies may be able to minimize future pandemic impacts by prioritizing rapid vaccine roll-out.

Towards developing multistrain PEDV vaccines: Integrating basic concepts and SARS-CoV-2 pan-sarbecovirus strategies

Porcine epidemic diarrhea virus (PEDV) is a major pathogen impacting the global pig industry, with outbreaks causing significant financial losses. The genetic variability of PEDV has posed challenges for vaccine development since its identification in the 1970s, a problem that intensified with its global emergence in the 2010s. Since current vaccines provide limited cross-protection against PEDV strains, and the development of multistrain PEDV vaccines remains an underexplored area of research, there is an urgent need for improved vaccine solutions. The rapid development of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines and ongoing pan-sarbecovirus vaccine research, have demonstrated the potential of next-generation vaccine platforms and novel antigen design strategies. These advancements offer valuable insights for the development of multistrain PEDV vaccines. This review summarizes key aspects of PEDV virology and explores multistrain vaccine development considering SARS-CoV-2 vaccine innovations, proposing a framework for developing next-generation PEDV vaccine solutions.

ALC-0315 Lipid-Based mRNA LNP Induces Stronger Cellular Immune Responses Postvaccination

At the end of 2019, SARS-CoV-2 emerged and rapidly spread, having a profound negative impact on human health and socioeconomic conditions. In response to this unprecedented global health crisis, significant advancements were made in the mRNA vaccine technology. In this study, we have compared the difference between two SARS-CoV-2 receptor-binding domain (RBD) mRNA-Lipid nanoparticle (LNP) vaccines prepared from two different ionizable cationic lipids: ALC-0315 and MC3. Characterization of RBD mRNA-LNPs showed that both MC3-LNP and ALC-0315-LNP are highly uniform and stable. Furthermore, we assessed the humoral immune response in mice after immunization; our findings indicated that both vaccine formulations effectively enhanced the formation and differentiation of germinal center (GC). Notably, the mice immunized with the ALC-0315-LNP vaccine elicited higher levels of IgG and its subclasses and significantly enhanced the activation of dendritic cells and T cells in draining lymph nodes (dLNs) compared to those immunized with the MC3-LNP vaccine. Further analysis of the T cell phenotype after splenic restimulation showed that mice injected with both LNP mRNA vaccines had significantly increased activation of the splenic T cells and Th1-type cytokine production. In addition, our finding showed that both LNP mRNA vaccines significantly increased the proportions of follicular helper T cells (Tfh) and long-lasting plasma cells in the dLNs of mice on day 14 postimmunization compared to control. In conclusion, both ALC-0315 and MC3 exhibited good stability and immunogenicity as mRNA-LNP recipes, but the ALC-0315-based mRNA-LNP vaccine showed higher efficacy in humoral and cellular immune responses compared to MC3.

Time to invest in cholera

The recent surge in cholera cases globally calls for urgent evaluation of current approaches to prevention and control of the disease. Malawi was one of the worst affected countries in 2022-2023 with the highest number of deaths due to cholera in the world. In this personal view, we look at Malawi as a case example to illustrate how current approaches lack sufficient investment. We review the history of cholera in Malawi and compare previous outbreaks to the 2022/23 outbreak. We discuss contributing factors to the outbreak including a lack of investment in water, sanitation and hygiene (both historically and currently), human resource constraints, and the market structures which make accessing oral cholera vaccine challenging both in the midst of an ongoing outbreak and as a preventative approach. We call for international action to address the economic and structural challenges underlying cholera persistence and propose solutions to prevent future epidemics and to eliminate cholera as a public health threat.

State of the Art and Emerging Technologies in Vaccine Design for Respiratory Pathogens

In this review, we present the efforts made so far in developing effective solutions to prevent infections caused by seven major respiratory pathogens: influenza virus, respiratory syncytial virus (RSV), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), Bordetella pertussis, Streptococcus pneumoniae (pneumococcus), Mycobacterium tuberculosis, and Pseudomonas aeruginosa. Advancements driven by the recent coronavirus disease 2019 (COVID-19) crisis have largely focused on viruses, but effective prophylactic solutions for bacterial pathogens are also needed, especially in light of the antimicrobial resistance (AMR) phenomenon. Here, we discuss various innovative key technologies that can help address this critical need, such as (a) the development of Lung-on-Chip ex vivo models to gain a better understanding of the pathogenesis process and the host-microbe interactions; (b) a more thorough investigation of the mechanisms behind mucosal immunity as the first line of defense against pathogens; (c) the identification of correlates of protection (CoPs) which, in conjunction with the Reverse Vaccinology 2.0 approach, can push a more rational and targeted design of vaccines. By focusing on these critical areas, we expect substantial progress in the development of new vaccines against respiratory bacterial pathogens, thereby enhancing global health protection in the framework of the increasingly concerning AMR emergence.

Comprehensive analyses of immune activity in COVID-19-vaccinated idiopathic pulmonary fibrosis patients

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease, characterized by impaired wound repair, tissue remodeling and fibrosis. Immune system may participate in the development and progression of the disease as indicated by altered activity in IPF sufferers. This study investigates the immune response to the BNT162b2 COVID-19 vaccine in patients with IPF compared to healthy controls, with a particular focus on evaluation of antibody responses, interferon-gamma release, cytokine profiling and a broad panel of immune cell subpopulations. IPF patients without prior exposure to SARS-CoV-2 had undetectable levels of anti-N IgG antibodies, highlighting their lack of previous infection. After vaccination, IPF patients showed a significant increase in anti-S1 IgG and IgA antibodies, though their levels were lower compared to healthy controls and convalescent IPF patients. Additionally, IPF patients exhibited altered proportions of regulatory T cells (Tregs) and effector T lymphocytes (Teffs) before and after vaccination. Specifically, IPF patients had higher percentages of Tregs with a Th2 phenotype and Th17 Tregs, along with reduced proportions of Th1/17 Tregs. Teffs in IPF patients showed a decrease in Th1-like and Th2-like populations after vaccination. Moreover, IPF patients demonstrated elevated populations of cytotoxic T lymphocytes (Tc) before vaccination and increased levels of γδ Tc cells throughout the study. Alterations in cytokine profiles were also observed, IPF patients showed higher levels of IL-6 and IL-22 compared to healthy controls. These findings suggest a distinct immune response in IPF patients to the COVID-19 vaccine, characterized by differences in antibody production, T cell differentiation and cytokine secretion compared to healthy individuals.

Developer and Partnership Differences in COVID-19 and Other Infections: Insights from DNA Vaccines

Historically, vaccine development has been heavily supported by government and public institutions. On the other hand, private biopharmaceutical companies have played a significant role in the development of innovative new therapies using novel pharmaceutical technologies. COVID-19 vaccines using new vaccine technologies, such as mRNA and adenoviral vectors, were rapidly developed by emerging biopharmaceutical companies in collaboration with large corporations and public organizations. This underscores the crucial role of emerging biopharma and public-private partnerships in advancing new vaccine technologies. While these innovations have been suggested as models for future vaccines, their applicability to other infectious diseases requires careful assessment. This study investigated the characteristics of the developers and partnerships in the development of DNA vaccines as a next-generation vaccine platform. The analysis revealed that while emerging biopharmaceutical companies and private-private and private-public partnerships were crucial during the COVID-19 pandemic, public organizations and public-public collaborations primarily led to the clinical development of vaccines for other diseases. Strategies for vaccine development using new vaccine technologies should be tailored to the specific characteristics of each disease.

Psychosocial Factors Inhibiting Timely COVID-19 Vaccination and Booster Receipt Among Transgender and Gender Diverse Adults

Purpose

The goal of this study was to assess possible psychosocial contributors to delayed coronavirus disease 2019 (COVID-19) vaccination within a sample of transgender and gender diverse (TGD) individuals.

Methods

TGD participants (N=385) were recruited from Prolific.co. Survey items assessed COVID-19 vaccination status, experiences of discrimination in health care settings, medical mistrust, COVID-19 mistrust, and perceived barriers to vaccination. Logistic regressions were conducted using SPSS version 27 to assess whether demographic variables, medical mistrust, experiences of discrimination in health care, and COVID-19 mistrust predicted vaccination behaviors. A PATH model was developed using AMOS 21.0 to assess the relationship among experiences of discrimination, general medical mistrust, COVID-19 mistrust, and barriers to vaccination in predicting receipt of a booster at the time of the study.

Results

Results from the logistic regressions indicated a binary TGD identity and higher COVID-19 mistrust predicted experiencing a delayed first dose of a COVID-19 vaccination and receipt of a booster at the time of the study over and above racial identity, experiences of discrimination, and general medical mistrust. Results from a PATH model indicated an association among experiences of discrimination in health care, medical mistrust, COVID-19 mistrust, barriers to vaccination, and having not received a booster at the time of the study.

Conclusion

These findings support prior research demonstrating that vaccination rates among TGD individuals do not differ from other groups. However, TGD individuals with a binary gender may have experienced or anticipated experiencing barriers to COVID-19 vaccination and/or receipt of a booster. Public health and clinical implications for these findings are discussed.

Party and play: Associations between US male sex workers' internet advertising characteristics and advertising chemsex to prospective clients

INTRODUCTION

It is broadly recognised that chemsex is more prevalent among men who have sex with men, but little is known about chemsex in the context of commercial sexual encounters between men. This study investigates sex worker advertising characteristics and their advertised willingness to engage in chemsex with clients.

METHODS

Data were web scraped from the profiles of US-based male sex workers (N = 3773) advertising services on an internet advertising platform in February 2021. This study describes the association between chemsex advertising and advertised age, race/ethnicity, sexual orientation, encounter type and COVID-19 acknowledgement.

RESULTS

28.5% of sex workers (n = 1077) advertised chemsex, 64.7% of whom were 25-34 years-old (n = 697). The odds of chemsex advertising increased between ages 21-24 (aOR = 1.20, 95% CI 1.09-1.32) and declined among sex workers over 35 years-old (aOR = 0.97, 95% CI 0.95-1.00). Sex workers advertising as bisexual were more likely to advertise chemsex than those identifying as gay (aOR = 1.38, 95% CI 1.18-1.63). Sex workers acknowledging COVID-19 were less likely to advertise chemsex compared to those who did not (aOR = 0.65, 95% CI 0.48-0.89). Encounter type was associated with chemsex advertising among sex workers in this sample; sex workers not offering the "boyfriend experience" were more than 50% less likely to advertise chemsex than those who did offer the boyfriend experience (aOR = 0.47, 95% CI 0.36-0.61).

DISCUSSION AND CONCLUSIONS

Chemsex advertising in this population is likely influenced by multiple sociodemographic and occupational characteristics. Identifying sex workers likely to engage in chemsex based on advertising data could inform targeted education and harm-reduction campaigns in this population.

The Impact of COVID-19 on RNA Therapeutics: A Surge in Lipid Nanoparticles and Alternative Delivery Systems

The COVID-19 pandemic has significantly accelerated progress in RNA-based therapeutics, particularly through the successful development and global rollout of mRNA vaccines. This review delves into the transformative impact of the pandemic on RNA therapeutics, with a strong focus on lipid nanoparticles (LNPs) as a pivotal delivery platform. LNPs have proven to be critical in enhancing the stability, bioavailability, and targeted delivery of mRNA, facilitating the unprecedented success of vaccines like those developed by Pfizer-BioNTech and Moderna. Beyond vaccines, LNP technology is being explored for broader therapeutic applications, including treatments for cancer, rare genetic disorders, and infectious diseases. This review also discusses emerging RNA delivery systems, such as polymeric nanoparticles and viral vectors, which offer alternative strategies to overcome existing challenges related to stability, immune responses, and tissue-specific targeting. Additionally, we examine the pandemic's influence on regulatory processes, including the fast-tracked approvals for RNA therapies, and the surge in research funding that has spurred further innovation in the field. Public acceptance of RNA-based treatments has also grown, laying the groundwork for future developments in personalized medicine. By providing an in-depth analysis of these advancements, this review highlights the long-term impact of COVID-19 on the evolution of RNA therapeutics and the future of precision drug delivery technologies.

Safety pharmacology of human endogenous retrovirus-enveloped baculoviral DNA vaccines against SARS-CoV-2 in Sprague-Dawley rats and beagle dogs

The coronavirus disease 2019 (COVID-19) emerged as a major global health crisis, posing significant health, economic, and social challenges. Vaccine development has been a crucial response to the severe-acute-respiratory-syndrome-related coronavirus-2 pandemic owing to the critical role of immunization in controlling infectious diseases, leading to the expedited development of several effective vaccines. Although mRNA platform-based COVID-19 vaccines authorized under emergency-use authorization have been administered globally, concerns regarding the vaccines have increased owing to the occurrence of various side effects. The present study aimed to evaluate the safety of a non-replicating recombinant baculovirus expressing the human endogenous retrovirus envelope gene (AcHERV) vaccine encoding SARS-CoV-2 antigens. Owing to the limited number of existing safety pharmacology studies on AcHERV as a viral vector vaccine, we conducted neurobehavior (Modified Irwin's Test), body temperature, and respiratory function studies in rats and cardiovascular system studies in male beagle dogs, which were administered the AcHERV-COVID-19 vaccine using telemetry. The safety assessment revealed no significant toxicological alterations. However, in rats, both sexes administered with the AcHERV-COVID-19 vaccine exhibited a temporary increase in body temperature, which normalized or showed signs of recovery. In conclusion, AcHERV-COVID-19 demonstrates a sufficient safety profile that supports its potential evaluation in future clinical trials.

COVID-19 Testing Among People with HIV: A Population Level Analysis Based on Statewide Data in South Carolina

People with HIV (PWH) are at an elevated risk of developing severe COVID-19 outcomes because of compromised immunity and more comorbidities. However, existing literature suggests a lower rate of COVID-testing among PWH. This study aimed to explore the temporal trend of county-level COVID-19 testing rate and multi-level predictors of COVID-19 ever-testing among PWH in South Carolina (SC). Leveraging linked statewide HIV and COVID-19 datasets, we defined the study population as all adult (18 + years) PWH who were alive on March 2020 and living in SC. PWH with a COVID-19 testing record between March 2020 and October 2021 were defined as COVID-19 ever-testers. Logistic regression and generalized mixed models were used to investigate the association of PWH's demographic profile, HIV clinical characteristics (e.g., CD4 count, viral load), comorbidities, and social factors with COVID-19 testing among PWH. Among 15,660 adult PWH, 8,005 (51.12%) had ever tested for COVID-19 during the study period (March 2020-October 2021). PWH with older age, being male, and Hispanics were less likely to take COVID-19 testing, while men who have sex with men or injection drug users were more likely to take COVID-19 testing. PWH with higher recent viral load (10,000-100,000 copies/ml vs. <200 copies/ml: adjusted odds ratio [AOR]: 0.64, 95%CI: 0.55-0.75) and lower CD4 counts (> 350 cells/mm3 vs. <200 cells/mm3: AOR: 1.25, 95%CI: 1.09-1.45) had lower odds for COVID-19 testing. Additionally, PWH with lower comorbidity burden and those living in rural areas were less likely to be tested for COVID-19. Differences in COVID-19 test-seeking behaviors were observed among PWH in the current study, which could help provide empirical evidence to inform the prioritization of further disease monitoring and targeted intervention. More efforts on building effective surveillance and screening systems are needed to allow early case detection and curbing disease transmission among older, male, Hispanic, and immune-suppressed PWH, especially in rural areas.

Infectious diseases and global security: Analysis of global control and vaccination strategies

Introduction: Given the recent experience with the COVID-19 vaccine campaign, an optimal global policy to control future pandemics and ensure infectious security globally is highly relevant. Objective: The study aims to determine the optimal vaccination strategy to reduce COVID-19 morbidity and mortality during a pandemic.Methods: A systematic search of studies on infectious disease control and vaccination strategies for the period 2000-2023 in PubMed, Scopus, Web of Science and Google Scholar databases using keywords was conducted for the review. Relevant publications, data extraction and systematisation were selected.Results: The findings of the analysis highlight the importance of integrated interventions in global vaccination strategies, including health systems strengthening, innovative technologies for outbreak detection and international collaboration. Vaccination, as an effective preventive measure, significantly reduces the spread of infectious diseases. Vaccination with different types of vaccines has been shown to improve immune response compared to the use of the same type of vaccine. This approach, where the first and second vaccine doses are different, may increase the effectiveness of the immune response.Conclusions: Studies confirm that vaccination reduces the number of cases and deaths, reducing the economic burden. A variety of vaccines, including mRNA, vector, and inactivated vaccines, provide high efficacy in preventing COVID-19 infection and mortality, especially when a heterologous vaccination regimen is used. This review identifies the most effective infectious disease control strategies for the development of global health recommendations

U.S. COVID-19 vaccine distribution strategies, systems, performance, and lessons learned, December 2020 - May 2023

During December 2020 through May 2023, the Centers for Disease Control and Prevention's (CDC) Immunization Services Division supported and executed the largest vaccine distribution effort in U.S. history, delivering nearly one billion doses of COVID-19 vaccine to vaccine providers in all 50 states, District of Columbia, Puerto Rico, Virgin Islands, Guam, Federated States of Micronesia, American Samoa, Marshall Islands, Northern Mariana Islands, and Palau. While existing infrastructure, ordering, and distribution mechanisms were in place from the Vaccines for Children Program (VFC) and experience had been gained during the 2009 H1N1 pandemic and incorporated into influenza vaccination pandemic planning, the scale and complexity of the national mobilization against a novel coronavirus resulted in many previously unforeseen challenges, particularly related to transporting and storing the majority of the U.S. COVID-19 vaccine at frozen and ultra-cold temperatures. This article describes the infrastructure supporting the distribution of U.S. government-purchased COVID-19 vaccines that was in place pre-pandemic, and the infrastructure, processes, and communications efforts developed to support the heightened demands of the COVID-19 vaccination program, and describes lessons learned.

Preclinical assessment of a recombinant RBD-Fc fusion protein as SARS-CoV-2 candidate vaccine

Background

Waning immunity and emergence of new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), highlight the need for further research in vaccine development.

Methods

A recombinant fusion protein containing the receptor-binding domain (RBD) fused to the human IgG1 Fc (RBD-Fc) was produced in CHO-K1 cells. RBD-Fc was emulsified with four adjuvants to evaluate its immunogenicity. The RBD-specific humoral and cellular immune responses were assessed by ELISA. The virus neutralizing potency of the vaccine was investigated using four neutralization methods. Safety was studied in mice and rabbits, and Antibody-Dependent Enhancement (ADE) effects were investigated by flow cytometry.

Results

RBD-Fc emulsified in Alum induced a high titer of anti-RBD antibodies with remarkable efficacy in neutralizing both pseudotyped and live SARS-CoV-2 Delta variant. The neutralization potency dropped significantly in response to the Omicron variant. RBD-Fc induced both TH2 and particularly TH1 immune responses. Histopathologic examinations demonstrated no substantial pathologic changes in different organs. No changes in serum biochemical and hematologic parameters were observed. ADE effect was not observed following immunization with RBD-Fc.

Conclusion

RBD-Fc elicits highly robust neutralizing antibodies and cellular immune responses, with no adverse effects. Therefore, it could be considered a promising and safe subunit vaccine against SARS-CoV-2.

Design and lyophilization of mRNA-encapsulating lipid nanoparticles

The remarkable success of two FDA-approved mRNA-encapsulating vaccines (Comirnaty® and Spikevax®) indicated the importance of lipid nanoparticles (LNPs) delivery systems in clinical use. Currently, mRNA-encapsulating LNPs (mRNA-LNPs) vaccines are stored as frozen liquid at low or ultralow temperatures. We designed lyophilized LNPs utilizing FDA-approved lipids to expedite the clinical application of our developed lyophilized mRNA-LNPs in the future. The key parameters of sucrose concentration and the selection and molar ratio of the four lipids in these vaccines were optimized for long-term stability with high transfection efficiency after lyophilization. We demonstrated that 8.7% sucrose is the optimal cryoprotectant concentration to maintain the transfection efficiency of lyophilized mRNA-LNPs. Optimal lipid formulations with high transfection efficiency both before and after lyophilization were screened using an orthogonal experimental design. The ratios of distearoylphosphatidylcholine (DSPC)/cholesterol and the selection of the ionizable and PEGylated lipids are the main factors influencing the long-term stability of mRNA-LNPs. Comparative mouse transfection experiments showed that the optimal lyophilized mRNA-LNPs maintained high mRNA expression after lyophilization, predominantly in the spleen or liver, with no expression in the kidneys or eyes. Our studies demonstrated the importance of the sucrose concentration and of the selection and molar ratio of the four lipids composing LNPs for maintaining mRNA-LNP stability under lyophilization and for long-term storage under mild conditions.

Development of T cell antigen-based human coronavirus vaccines against nAb-escaping SARS-CoV-2 variants

Currently approved vaccines have been successful in preventing the severity of COVID-19 and hospitalization. These vaccines primarily induce humoral immune responses; however, highly transmissible and mutated variants, such as the Omicron variant, weaken the neutralization potential of the vaccines, thus, raising serious concerns about their efficacy. Additionally, while neutralizing antibodies (nAbs) tend to wane more rapidly than cell-mediated immunity, long-lasting T cells typically prevent severe viral illness by directly killing infected cells or aiding other immune cells. Importantly, T cells are more cross-reactive than antibodies, thus, highly mutated variants are less likely to escape lasting broadly cross-reactive T cell immunity. Therefore, T cell antigen-based human coronavirus (HCoV) vaccines with the potential to serve as a supplementary weapon to combat emerging SARS-CoV-2 variants with resistance to nAbs are urgently needed. Alternatively, T cell antigens could also be included in B cell antigen-based vaccines to strengthen vaccine efficacy. This review summarizes recent advancements in research and development of vaccines containing T cell antigens or both T and B cell antigens derived from proteins of SARS-CoV-2 variants and/or other HCoVs based on different vaccine platforms.

Germinal Center Response to mRNA Vaccination and Impact of Immunological Imprinting on Subsequent Vaccination

Vaccines are the most effective intervention currently available, offering protective immunity against targeted pathogens. The emergence of the coronavirus disease 2019 pandemic has prompted rapid development and deployment of lipid nanoparticle encapsulated, mRNA-based vaccines. While these vaccines have demonstrated remarkable immunogenicity, concerns persist regarding their ability to confer durable protective immunity to continuously evolving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. This review focuses on human B cell responses induced by SARS-CoV-2 mRNA vaccination, with particular emphasis on the crucial role of germinal center reactions in shaping enduring protective immunity. Additionally, we explored observations of immunological imprinting and dynamics of recalled pre-existing immunity following variants of concern-based booster vaccination. Insights from this review contribute to comprehensive understanding B cell responses to mRNA vaccination in humans, thereby refining vaccination strategies for optimal and sustained protection against evolving coronavirus variants.

Coding Therapeutic Nucleic Acids from Recombinant Proteins to Next-Generation Vaccines: Current Uses, Limitations, and Future Horizons

This study aims to highlight the potential use of cTNAs in therapeutic applications. The COVID-19 pandemic has led to significant use of coding therapeutic nucleic acids (cTNAs) in terms of DNA and mRNA in the development of vaccines. The use of cTNAs resulted in a paradigm shift in the therapeutic field. However, the injection of DNA or mRNA into the human body transforms cells into biological factories to produce the necessary proteins. Despite the success of cTNAs in the production of corona vaccines, they have several limitations such as instability, inability to cross biomembranes, immunogenicity, and the possibility of integration into the human genome. The chemical modification and utilization of smart drug delivery cargoes resolve cTNAs therapeutic problems. The success of cTNAs in corona vaccine production provides perspective for the eradication of influenza viruses, Zika virus, HIV, respiratory syncytial virus, Ebola virus, malaria, and future pandemics by quick vaccine design. Moreover, the progress cTNAs technology is promising for the development of therapy for genetic disease, cancer therapy, and currently incurable diseases.

The Protective Efficacy of a SARS-CoV-2 Vaccine Candidate B.1.351V against Several Variant Challenges in K18-hACE2 Mice

The emergence of SARS-CoV-2 variants of concern (VOCs) with increased transmissibility and partial resistance to neutralization by antibodies has been observed globally. There is an urgent need for an effective vaccine to combat these variants. Our study demonstrated that the B.1.351 variant inactivated vaccine candidate (B.1.351V) generated strong binding and neutralizing antibody responses in BALB/c mice against the B.1.351 virus and other SARS-CoV-2 variants after two doses within 28 days. Immunized K18-hACE2 mice also exhibited elevated levels of live virus-neutralizing antibodies against various SARS-CoV-2 viruses. Following infection with these viruses, K18-hACE2 mice displayed a stable body weight, a high survival rate, minimal virus copies in lung tissue, and no lung damage compared to the control group. These findings indicate that B.1.351V offered protection against infection with multiple SARS-CoV-2 variants in mice, providing insights for the development of a vaccine targeting SARS-CoV-2 VOCs for human use.

Rapid Development of a Registry to Accelerate COVID-19 Vaccine Clinical Trials

Background

The unprecedented scientific response to the SARS-Cov-2 pandemic in 2020 required the rapid development and activation of extensive clinical trial networks to study vaccines and therapeutics. The COVID-19 Prevention Network (CoVPN) coordinated hundreds of sites conducting phase 2 and 3 clinical trials of vaccines and antibody therapeutics. To facilitate these clinical trials, the CoVPN Volunteer Screening Registry (VSR) was created to collect volunteer information at scale, identify volunteers at risk of COVID-19 who met enrollment criteria, distribute candidates across clinical trial sites, and enable monitoring of volunteering and enrollment progress.

Methods

We developed a secure database to support three primary web-based interfaces: a national volunteer questionnaire intake form, a clinical trial site portal, and an Administrative Portal. The Site Portal supported filters based on volunteer attributes, visual analytics, enrollment status tracking, geographic search, and clinical risk prediction. The Administrative Portal supported oversight and development with pre-specified reports aggregated by geography, trial, and trial site; charts of volunteer rates over time; volunteer risk score calculation; and dynamic, user-defined reports.

Findings

Over 650,000 volunteers joined the VSR, and 1094 users were trained to utilize the system. The VSR played a key role in recruitment for the Moderna, Oxford-AstraZeneca, Janssen, and Novavax vaccine clinical trials, provided support to the Pfizer and Sanofi vaccine and prophylactic antibody clinical trials, and enhanced the diversity of trial participants. Clinical trial sites selected 166,729 volunteer records for follow-up screening, and of these 47·7% represented groups prioritized for increased enrollment. Despite the unprecedented urgency of its development, the system maintained 99·99% uptime.

Interpretation

The success of the VSR demonstrates that information tools can be rapidly yet safely developed through a public-private partnership and integrated into a distributed and accelerated clinical trial setting. We further summarize the requirements, design, and development of the system, and discuss lessons learned for future pandemic preparedness.

mRNA-LNP HIV-1 trimer boosters elicit precursors to broad neutralizing antibodies

Germline-targeting (GT) HIV vaccine strategies are predicated on deriving broadly neutralizing antibodies (bnAbs) through multiple boost immunogens. However, as the recruitment of memory B cells (MBCs) to germinal centers (GCs) is inefficient and may be derailed by serum antibody-induced epitope masking, driving further B cell receptor (BCR) modification in GC-experienced B cells after boosting poses a challenge. Using humanized immunoglobulin knockin mice, we found that GT protein trimer immunogen N332-GT5 could prime inferred-germline precursors to the V3-glycan-targeted bnAb BG18 and that B cells primed by N332-GT5 were effectively boosted by either of two novel protein immunogens designed to have minimum cross-reactivity with the off-target V1-binding responses. The delivery of the prime and boost immunogens as messenger RNA lipid nanoparticles (mRNA-LNPs) generated long-lasting GCs, somatic hypermutation, and affinity maturation and may be an effective tool in HIV vaccine development.

Association between receiving Covid-19 vaccine and menstrual cycle patterns among childbearing women: A cross-sectional study

Background and Aims

Many women reported experiencing abnormalities in their cycle after being vaccinated with Covid-19 vaccination. To understand this issue further, our study aimed to evaluate the menstrual cycle patterns among women of childbearing age after receiving COVID-19 vaccinations.

Methods

A cross-sectional study was conducted to investigate the impact of COVID-19 vaccine on women aged 18 years and above in Saudi Arabia. A self-administered online questionnaire was distributed among participants who had received at least one dose of COVID-19 vaccine. The questionnaire included questions about the participants' demographic characteristics, medical history, and vaccine-related adverse events.

Results

The study included 383 female participants with an average age of 30.8 ± 8.1 years. The majority of participants, 92.7%, were Saudi, and more than half, 51.4%, were single. Of the participants, 78.9% were disease-free, and a majority of 67.9% had no history of Coronavirus Disease 2019 infection. A significant proportion of participants reported postvaccination changes in the menstrual cycle. Specifically, 43.1% reported changes after the first dose, and 38.4% reported changes after the second dose (p = 0.044). The severity of premenstrual symptoms increased from 44 (11.5%) to 113 (29.5%) after the first dose. Reported pain on the (WONG-BAKER) scale was also significantly elevated from 34 (8.9%) to 87 (22.7%) (p < 0.001) after the first dose.

Conclusion

A relatively high prevalence of menstrual cycle irregularities was reported by Saudi vaccinated women, particularly young adults. These findings suggest the need to further research and explore the underlying causes of these irregularities and develop interventions that may help mitigate their impact on women's health. It is also recommended that women who observe long-term changes in their menstrual cycles seek follow-up and consultation with healthcare providers to ensure that any potential health concerns are addressed promptly.

New Anticancer Drugs: Reliably Assessing "Value" While Addressing High Prices

Countries face challenges in paying for new drugs. High prices are driven in part by exploding drug development costs, which, in turn, are driven by essential but excessive regulation. Burdensome regulation also delays drug development, and this can translate into thousands of life-years lost. We need system-wide reform that will enable less expensive, faster drug development. The speed with which COVID-19 vaccines and AIDS therapies were developed indicates this is possible if governments prioritize it. Countries also differ in how they value drugs, and generally, those willing to pay more have better, faster access. Canada is used as an example to illustrate how "incremental cost-effectiveness ratios" (ICERs) based on measures such as gains in "quality-adjusted life-years" (QALYs) may be used to determine a drug's value but are often problematic, imprecise assessments. Generally, ICER/QALY estimates inadequately consider the impact of patient crossover or long post-progression survival, therapy benefits in distinct subpopulations, positive impacts of the therapy on other healthcare or societal costs, how much governments willingly might pay for other things, etc. Furthermore, a QALY value should be higher for a lethal or uncommon disease than for a common, nonlethal disease. Compared to international comparators, Canada is particularly ineffective in initiating public funding for essential new medications. Addressing these disparities demands urgent reform.

The glycosaminoglycan-binding chemokine fragment CXCL9(74-103) reduces inflammation and tissue damage in mouse models of coronavirus infection

Introduction

Pulmonary diseases represent a significant burden to patients and the healthcare system and are one of the leading causes of mortality worldwide. Particularly, the COVID-19 pandemic has had a profound global impact, affecting public health, economies, and daily life. While the peak of the crisis has subsided, the global number of reported COVID-19 cases remains significantly high, according to medical agencies around the world. Furthermore, despite the success of vaccines in reducing the number of deaths caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there remains a gap in the treatment of the disease, especially in addressing uncontrolled inflammation. The massive recruitment of leukocytes to lung tissue and alveoli is a hallmark factor in COVID-19, being essential for effectively responding to the pulmonary insult but also linked to inflammation and lung damage. In this context, mice models are a crucial tool, offering valuable insights into both the pathogenesis of the disease and potential therapeutic approaches.

Methods

Here, we investigated the anti-inflammatory effect of the glycosaminoglycan (GAG)-binding chemokine fragment CXCL9(74-103), a molecule that potentially decreases neutrophil transmigration by competing with chemokines for GAG-binding sites, in two models of pneumonia caused by coronavirus infection.

Results

In a murine model of betacoronavirus MHV-3 infection, the treatment with CXCL9(74-103) decreased the accumulation of total leukocytes, mainly neutrophils, to the alveolar space and improved several parameters of lung dysfunction 3 days after infection. Additionally, this treatment also reduced the lung damage. In the SARS-CoV-2 model in K18-hACE2-mice, CXCL9(74-103) significantly improved the clinical manifestations of the disease, reducing pulmonary damage and decreasing viral titers in the lungs.

Discussion

These findings indicate that CXCL9(74-103) resulted in highly favorable outcomes in controlling pneumonia caused by coronavirus, as it effectively diminishes the clinical consequences of the infections and reduces both local and systemic inflammation.

A novel deep generative model for mRNA vaccine development: Designing 5' UTRs with N1-methyl-pseudouridine modification

Efficient translation mediated by the 5' untranslated region (5' UTR) is essential for the robust efficacy of mRNA vaccines. However, the N1-methyl-pseudouridine (m1Ψ) modification of mRNA can impact the translation efficiency of the 5' UTR. We discovered that the optimal 5' UTR for m1Ψ-modified mRNA (m1Ψ-5' UTR) differs significantly from its unmodified counterpart, highlighting the need for a specialized tool for designing m1Ψ-5' UTRs rather than directly utilizing high-expression endogenous gene 5' UTRs. In response, we developed a novel machine learning-based tool, Smart5UTR, which employs a deep generative model to identify superior m1Ψ-5' UTRs in silico. The tailored loss function and network architecture enable Smart5UTR to overcome limitations inherent in existing models. As a result, Smart5UTR can successfully design superior 5' UTRs, greatly benefiting mRNA vaccine development. Notably, Smart5UTR-designed superior 5' UTRs significantly enhanced antibody titers induced by COVID-19 mRNA vaccines against the Delta and Omicron variants of SARS-CoV-2, surpassing the performance of vaccines using high-expression endogenous gene 5' UTRs.

Current Progress, Challenges and Prospects in the Development of COVID-19 Vaccines

The COVID-19 pandemic has resulted in over 772 million confirmed cases, including nearly 7 million deaths, according to the World Health Organization (WHO). Leveraging rapid development, accelerated vaccine approval processes, and large-scale production of various COVID-19 vaccines using different technical platforms, the WHO declared an end to the global health emergency of COVID-19 on May 5, 2023. Current COVID-19 vaccines encompass inactivated, live attenuated, viral vector, protein subunit, nucleic acid (DNA and RNA), and virus-like particle (VLP) vaccines. However, the efficacy of these vaccines is diminishing due to the constant mutation of SARS-CoV-2 and the heightened immune evasion abilities of emerging variants. This review examines the impact of the COVID-19 pandemic, the biological characteristics of the virus, and its diverse variants. Moreover, the review underscores the effectiveness, advantages, and disadvantages of authorized COVID-19 vaccines. Additionally, it analyzes the challenges, strategies, and future prospects of developing a safe, broad-spectrum vaccine that confers sufficient and sustainable immune protection against new variants of SARS-CoV-2. These discussions not only offer insight for the development of next-generation COVID-19 vaccines but also summarize experiences for combating future emerging viruses.

Comparison of Axillary Lymph Nodes on Breast MRI Before and After COVID-19 Booster Vaccination

RATIONALE AND OBJECTIVES

Vaccine-related lymphadenopathy is a frequent finding following initial coronavirus disease 2019 (COVID-19) vaccination, but the frequency after COVID-19 booster vaccination is still unknown. In this study we compare axillary lymph node morphology on breast MRI before and after COVID-19 booster vaccination.

MATERIALS AND METHODS

This retrospective, single-center, IRB-approved study included patients who underwent breast MRI between October 2021 and December 2021 after the COVID-19 booster vaccination. The axillary lymph node with the greatest cortical thickness ipsilateral to the side of vaccination was measured on MRI after booster vaccination and before initial COVID-19 vaccination. Comparisons were made between patients with and without increase in cortical thickness of ≥ 0.2 cm. Continuous covariates were compared using Wilcoxon rank-sum test and categorical covariates were compared using Fisher's exact test. Multiple comparison adjustment was made using the Benjamini-Hochberg procedure.

RESULTS

All 128 patients were included. Twenty-four of 128 (19%) displayed an increase in lymph node cortical thickness of ≥ 0.2 cm. Patients who received the booster more recently were more likely to present cortical thickening, with a median of 9 days (IQR 5, 20) vs. 36 days (IQR 18, 59) (p < 0.001). Age (p = 0.5) and type of vaccine (p = 0.7) were not associated with thickening. No ipsilateral breast cancer or malignant lymphadenopathy were diagnosed on follow-up.

CONCLUSION

Axillary lymphadenopathy on breast MRI following COVID-19 booster vaccination is a frequent finding, especially in the first 3 weeks after vaccination. Additional evaluation or follow-up may be omitted in patients with low concern for malignancy.

Working towards the development of vaccines and chemotherapeutics against neosporosis-With all of its ups and downs-Looking ahead

Neospora caninum is an apicomplexan and obligatory intracellular parasite, which is the leading cause of reproductive failure in cattle and affects other farm and domestic animals, but also induces neuromuscular disease in dogs of all ages. In cattle, neosporosis is an important health problem, and has a considerable economic impact. To date there is no protective vaccine or chemotherapeutic treatment on the market. Immuno-prophylaxis has long been considered as the best control measure. Proteins involved in host cell interaction and invasion, as well as antigens mediating inflammatory responses have been the most frequently assessed vaccine targets. However, despite considerable efforts no effective vaccine has been introduced to the market to date. The development of effective compounds to limit the effects of vertical transmission of N. caninum tachyzoites has emerged as an alternative or addition to vaccination, provided suitable targets and safe and efficacious drugs can be identified. Additionally, the combination of both treatment strategies might be interesting to further increase protectivity against N. caninum infections and to decrease the duration of treatment and the risk of potential drug resistance. Well-established and standardized animal infection models are key factors for the evaluation of promising vaccine and compound candidates. The vast majority of experimental animal experiments concerning neosporosis have been performed in mice, although in recent years the numbers of experimental studies in cattle and sheep have increased. In this review, we discuss the recent findings concerning the progress in drug and vaccine development against N. caninum infections in mice and ruminants.

In search of a pan-coronavirus vaccine: next-generation vaccine design and immune mechanisms

Members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent history. In this review, we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus family. We will detail the unmet clinical need associated with the continued transmission of SARS-CoV-2, MERS-CoV and the four seasonal coronaviruses (HCoV-OC43, NL63, HKU1 and 229E) in humans and the potential for future zoonotic coronaviruses. We will highlight how first-generation SARS-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine design. We will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer cross-protection. Finally, we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

Omicron-specific and bivalent omicron-containing vaccine candidates elicit potent virus neutralisation in the animal model

Omicron variant (B.1.1.529) is able to escape from naturally acquired and vaccine-induced immunity, which mandates updating the current COVID-19 vaccines. Here, we investigated and compared the neutralising antibody induction of the ancestral variant-based BIV1-CovIran vaccine, the Omicron variant-based BIV1-CovIran Plus vaccine, and the novel bivalent vaccine candidate, BBIV1-CovIran, against the Omicron and ancestral Wuhan variants on the rat model. After inactivating the viral particles, the viruses were purified and formulated. Bivalent vaccines were a composition of 2.5 µg (5 µg total) or 5 µg (10 µg total) doses of each ansectral-based and Omicron-based monovalent vaccine. Subsequently, the potency of the monovalent and bivalent vaccines was investigated using the virus neutralisation test (VNT). The group that received three doses of the Omicron-specific vaccine demonstrated neutralisation activity against the Omicron variant with a geometric mean titer of 337.8. However, three doses of the Wuhan variant-specific vaccine could neutralise the Omicron variant at a maximum of 1/32 serum dilution. The neutralisation activity of the Omicron-specific vaccine, when administered as the booster dose after two doses of the Wuhan variant-specific vaccine, was 100% against the Omicron variant and the Wuhan variant at 1/64 and 1/128 serum dilution, respectively. Three doses of 5 µg bivalent vaccine could effectively neutralise both variants at the minimum of 1/128 serum dilution. The 10 µg bivalent vaccine at three doses showed even higher neutralisation titers: the geometric mean of 388 (95% CI 242.2-621.7) against Omicron and 445.7 (95% CI 303.3-655.0) against Wuhan. It is shown that the candidate bivalent and Omicron-specific vaccines could elicit a potent immune response against both Wuhan-Hu-1 and Omicron BA.1 variants.

ERS International Congress 2023: highlights from the Paediatrics Assembly

Respiratory health in children is essential for general wellbeing and healthy development in the short and long term. It is well known that many respiratory diseases in adulthood have their origins in early life, and therefore research on prevention of respiratory diseases and management of children with respiratory diseases will benefit patients during the full life course. Scientific and clinical advances in the field of respiratory health are moving at a fast pace. This article summarises some of the highlights in paediatric respiratory medicine presented at the hybrid European Respiratory Society (ERS) International Congress 2023 which took place in Milan (Italy). Selected sessions are summarised by Early Career Members of the Paediatrics Assembly (Assembly 7) under the supervision of senior ERS officers, and cover a wide range of research areas in children, including respiratory physiology and sleep, asthma and allergy, cystic fibrosis, respiratory infection and immunology, neonatology and intensive care, respiratory epidemiology and bronchology.

Bilateral Sequential Abducens Nerve Palsy After Pfizer-BioNTech COVID-19 Vaccine (BNT162b2): A Case Report and Literature Review

This case report details the occurrence of bilateral sequential abducens nerve palsy in a previously healthy 42-year-old woman two days after receiving her first dose of the Pfizer-BioNTech COVID-19 vaccine (BNT162b2). Despite the widespread global administration of COVID-19 vaccines, instances of abducens palsy following vaccination are limited in the available literature. Considering the temporal association between vaccination and symptom onset, the absence of underlying medical conditions predisposing to such neurological manifestations, normal brain imaging results, the occurrence of other cranial palsies post-vaccination, and analogous occurrences after different vaccinations, we propose a plausible connection between the patient's abducens palsy and the COVID-19 vaccination. Our findings contribute to the growing body of evidence regarding the side effects and safety profile of COVID-19 vaccines. Importantly, the resolution of symptoms with conservative management and the uneventful administration of the second vaccine dose suggest that the observed abducens palsy may be a transient and isolated reaction.

Effect of COVID-19 Vaccination on Menstrual Cycle Patterns of Reproductive-age Women: A Multi-centric Observational Study

AIM

The study was conducted to know the impact of COVID-19 vaccination on menstrual cycle patterns and pre- and post-menstrual symptoms in women aged 18-45 years.

BACKGROUND

COVID-19 vaccination was introduced to combat the dreadful impacts of human coronavirus infection. The two indigenously developed COVID-19 vaccines approved for use in India are COVISHIELD and COVAXIN.

OBJECTIVES

To investigate the effects of COVID-19 vaccination on the menstrual cycle, pre- and post-menstrual symptoms and to establish the correlation with the type of vaccine received.

METHODS

Multi-centric observational study conducted in six institutes of national importance in different states of India over one year. A total of 5709 female participants fulfilling inclusion criteria were enrolled. Data about the impact of vaccines (COVISHIELD and COVAXIN) and prior COVID-19 infection on the menstrual cycle and its associated symptoms were obtained using all participants' online and offline interviews.

RESULTS

Of 5709 participants, 78.2% received COVISHIELD and 21.8% COVAXIN. Of the total 5709 participants, 333 (5.8%) developed post-vaccination menstrual disturbances, with 32.7% having frequent cycles, 63.7% prolonged cycles, and 3.6% inter-menstrual bleeding. A total of 301 participants noticed changes in the amount of bleeding, with 50.2% excessive, 48.8% scanty, and 0.99% amenorrhea followed by heavy bleeding. Furthermore, the irregularities of the menstrual cycle (p = 0.011) and length (0.001) were significantly higher in the COVAXIN group (7.2%) as compared to the COVISHIELD (5.3%) group. A total of 721 participants complained of newly developed/worsening pre- and post-menstrual symptoms. These symptoms were significantly higher in the COVISHIELD group (p = 0.031), with generalized weakness and body pains as the main complaints (p = 0.001). No significant difference was observed in the incidence of COVID-19 infection with these vaccines. No significant associations were observed when comparing menstrual abnormalities among those with COVID-19 infection (p > 0.05).

CONCLUSION

COVISHIELD and COVAXIN vaccines were associated with menstrual cycle disturbances and pre-and post-menstrual symptoms in a small proportion of participants, with 94.7% having no change in the amount of bleeding during menstruation post-vaccination. The menstrual irregularities observed were significantly higher with the COVAXIN vaccine. Others: Further, long-term studies are required to confirm that the impact of COVID-19 vaccination on the menstrual cycle may be short-lasting, with no severe effects on women's menstrual health.

Mammalian Antigen Display for Pandemic Countermeasures

Pandemic countermeasures require the rapid design of antigens for vaccines, profiling patient antibody responses, assessing antigen structure-function landscapes, and the surveillance of emerging viral lineages. Cell surface display of a viral antigen or its subdomains can facilitate these goals by coupling the phenotypes of protein variants to their DNA sequence. Screening surface-displayed proteins via flow cytometry also eliminates time-consuming protein purification steps. Prior approaches have primarily relied on yeast as a display chassis. However, yeast often cannot express large viral glycoproteins, requiring their truncation into subdomains. Here, we describe a method to design and express antigens on the surface of mammalian HEK293T cells. We discuss three use cases, including screening of stabilizing mutations, deep mutational scanning, and epitope mapping. The mammalian antigen display platform described herein will accelerate ongoing and future pandemic countermeasures.

YouTube and COVID-19 vaccines: A mini scoping review

YouTube is a highly popular social media platform capable of widespread information dissemination about COVID-19 vaccines. The aim of this mini scoping review was to summarize the content, quality, and methodology of studies that analyze YouTube videos related to COVID-19 vaccines. COVIDENCE was used to screen search results based on inclusion and exclusion criteria. PRISMA was used for data organization, and the final list of 9 articles used in the mini review were summarized and synthesized. YouTube videos included in each study, total number of cumulative views, results, and limitations were described. Overall, most of the videos were uploaded by television and internet news media and healthcare professionals. A variety of coding schemas were used in the studies. Videos with misleading, inaccurate, or anti-vaccination sentiment were more often uploaded by consumers. Officials seeking to encourage vaccination may utilize YouTube for widespread reach and to debunk misinformation and disinformation.

Evaluation of Immune Response to Mucosal Immunization with an Oral Probiotic-Based Vaccine in Mice: Potential for Prime-Boost Immunization against SARS-CoV-2

Following the conclusion of the COVID-19 pandemic, the persistent genetic variability in the virus and its ongoing circulation within the global population necessitate the enhancement of existing preventive vaccines and the development of novel ones. A while back, we engineered an orally administered probiotic-based vaccine, L3-SARS, by integrating a gene fragment that encodes the spike protein S of the SARS-CoV-2 virus into the genome of the probiotic strain E. faecium L3, inducing the expression of viral antigen on the surface of bacteria. Previous studies demonstrated the efficacy of this vaccine candidate in providing protection against the virus in Syrian hamsters. In this present study, utilizing laboratory mice, we assess the immune response subsequent to immunization via the gastrointestinal mucosa and discuss its potential as an initial phase in a two-stage vaccination strategy. Our findings indicate that the oral administration of L3-SARS elicits an adaptive immune response in mice. Pre-immunization with L3-SARS enhances and prolongs the humoral immune response following a single subcutaneous immunization with a recombinant S-protein analogous to the S-insert of the coronavirus in Enterococcus faecium L3.

Metabolic and toxicological considerations regarding CGRP mAbs and CGRP antagonists to treat migraine in COVID-19 patients: a narrative review

INTRODUCTION

Migraine pharmacological therapies targeting calcitonin gene-related peptide (CGRP), including monoclonal antibodies and gepants, have shown clinical effect and optimal tolerability. Interactions between treatments of COVID-19 and CGRP-related drugs have not been reviewed.

AREAS COVERED

An overview of CGRP, a description of the characteristics of each CGRP-related drug and its response predictors, COVID-19 and its treatment, the interactions between CGRP-related drugs and COVID-19 treatment, COVID-19 and vaccination-induced headache, and the neurological consequences of Covid-19.

EXPERT OPINION

Clinicians should be careful about using gepants for COVID-19 patients, due to the potential drug interactions with drugs metabolized via CYP3A4 cytochrome. In particular, COVID-19 treatment (especially nirmatrelvir packaged with ritonavir, as Paxlovid) should be considered cautiously. It is advisable to stop or adjust the dose (10 mg atogepant when used for episodic migraine) of gepants when using Paxlovid (except for zavegepant). CGRP moncolconal antibodies (CGRP-mAbs) do not have drug - drug interactions, but a few days' interval between a COVID-19 vaccination and the use of CGRP mAbs is recommended to allow the accurate identification of the possible adverse effects, such as injection site reaction. Covid-19- and vaccination-related headache are known to occur. Whether CGRP-related drugs would be of benefit in these circumstances is not yet known.