Vaccines

17 pages, 2921 KiB

Open AccessArticle

Decision Regret and Vaccine Hesitancy among Nursing Students and Registered Nurses in Italy: Insights from Structural Equation Modeling

by Alice Silvia Brera, Cristina Arrigoni, Silvia Belloni, Gianluca Conte, Arianna Magon, Marco Alfredo Arcidiacono, Malgorzata Pasek, Galyna Shabat, Luigi Bonavina and Rosario Caruso

Vaccines 2024, 12(9), 1054; https://doi.org/10.3390/vaccines12091054 (registering DOI) - 14 Sep 2024

Abstract

This study focused on vaccine hesitancy and decision regret about the COVID-19 vaccine among nursing students (BScN and MScN) and Registered Nurses (RNs) in Italy. The primary aim was to describe decision regret and vaccine hesitancy among these groups and to understand what [...] Read more.

This study focused on vaccine hesitancy and decision regret about the COVID-19 vaccine among nursing students (BScN and MScN) and Registered Nurses (RNs) in Italy. The primary aim was to describe decision regret and vaccine hesitancy among these groups and to understand what influences vaccine hesitancy. Data were collected through an e-survey conducted from March to June 2024. The Decision Regret Scale and the Adult Vaccine Hesitancy Scale were employed to assess regret and hesitancy levels, assessing trust, concerns, and compliance regarding vaccination. Among the participants, 8.64% were not vaccinated. The results indicated moderate to high levels of decision regret and diverse levels of trust, concerns, and compliance with COVID-19 vaccination. Structural equation modeling revealed that decision regret significantly predicted Trust (R² = 31.3%) and Concerns (R² = 26.9%), with lower regret associated with higher trust and lower concerns about vaccine safety. The number of COVID-19 vaccine boosters was a significant predictor of Trust and Concerns, with more boosters associated with higher trust and lower concerns. MScN students exhibited higher Compliance compared to RNs (R² = 2.9%), highlighting the role of advanced education. These findings suggest that addressing decision regret and providing comprehensive vaccine information could enhance trust and compliance. Full article

(This article belongs to the Special Issue Advancing the Science on Vaccine Hesitancy to Inform Interventions)

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25 pages, 2569 KiB

Open AccessArticle

Preclinical Development of a Novel Zika Virus-like Particle Vaccine in Combination with Tetravalent Dengue Virus-like Particle Vaccines

by Dominik A. Rothen, Sudip Kumar Dutta, Pascal S. Krenger, Alessandro Pardini, Anne-Cathrine S. Vogt, Romano Josi, Ilva Lieknina, Albert D. M. E. Osterhaus, Mona O. Mohsen, Monique Vogel, Byron Martina, Kaspars Tars and Martin F. Bachmann

Vaccines 2024, 12(9), 1053; https://doi.org/10.3390/vaccines12091053 (registering DOI) - 14 Sep 2024

Abstract

Declared as a Public Health Emergency in 2016 by the World Health Organization (WHO), the Zika virus (ZIKV) continues to cause outbreaks that are linked to increased neurological complications. Transmitted mainly by Aedes mosquitoes, the virus is spread mostly amongst several tropical regions [...] Read more.

Declared as a Public Health Emergency in 2016 by the World Health Organization (WHO), the Zika virus (ZIKV) continues to cause outbreaks that are linked to increased neurological complications. Transmitted mainly by Aedes mosquitoes, the virus is spread mostly amongst several tropical regions with the potential of territorial expansion due to environmental and ecological changes. The ZIKV envelope protein’s domain III, crucial for vaccine development due to its role in receptor binding and neutralizing antibody targeting, was integrated into sterically optimized AP205 VLPs to create an EDIII-based VLP vaccine. To increase the potential size of domains that can be accommodated by AP205, two AP205 monomers were fused into a dimer, resulting in 90 rather than 180 N-/C- termini amenable for fusion. EDIII displayed on AP205 VLPs has several immunological advantages, like a repetitive surface, a size of 20–200 nm (another PASP), and packaged bacterial RNA as adjuvants (a natural toll-like receptor 7/8 ligand). In this study, we evaluated a novel vaccine candidate for safety and immunogenicity in mice, demonstrating its ability to induce high-affinity, ZIKV-neutralizing antibodies without significant disease-enhancing properties. Due to the close genetical and structural characteristics, the same mosquito vectors, and the same ecological niche of the dengue virus and Zika virus, a vaccine covering all four Dengue viruses (DENV) serotypes as well as ZIKV would be of significant interest. We co-formulated the ZIKV vaccine with recently developed DENV vaccines based on the same AP205 VLP platform and tested the vaccine mix in a murine model. This combinatory vaccine effectively induced a strong humoral immune response and neutralized all five targeted viruses after two doses, with no significant antibody-dependent enhancement (ADE) observed. Overall, these findings highlight the potential of the AP205 VLP-based combinatory vaccine as a promising approach for providing broad protection against DENV and ZIKV infections. Further investigations and preclinical studies are required to advance this vaccine candidate toward potential use in human populations. Full article

(This article belongs to the Special Issue Virus-Like Particle Vaccine Development)

10 pages, 549 KiB

Open AccessArticle

Using Vaccine Safety Data to Demonstrate the Potential of Pooled Data Analysis

by Steven Hawken, Lindsay A. Wilson and Kumanan Wilson

Vaccines 2024, 12(9), 1052; https://doi.org/10.3390/vaccines12091052 (registering DOI) - 14 Sep 2024

Abstract

In Canada, vaccine safety studies are often conducted at the provincial/territorial level where the primary data on vaccination reside. Combining health services data from multiple jurisdictions using a pooled data analytic approach would reduce the amount of time needed to detect vaccine safety [...] Read more.

In Canada, vaccine safety studies are often conducted at the provincial/territorial level where the primary data on vaccination reside. Combining health services data from multiple jurisdictions using a pooled data analytic approach would reduce the amount of time needed to detect vaccine safety signals. To determine the difference in the time it would take to identify safety signals using different proportions of the Canadian population, we conducted power and sample size calculations for a hypothetical self-controlled case series-based surveillance analysis. We used scenarios modeled after the real-world examples of myocarditis and vaccine-induced immune thrombotic thrombocytopenia (VITT) following COVID-19 vaccination as our base cases. Our calculations demonstrated that in the case of a myocarditis-type event, a pooled analysis would reduce the time needed to detect a safety signal by over 60% compared to using Ontario data alone. In the case of a VITT-type event, a pooled analysis could detect a safety signal 49 days sooner than using Ontario data alone, potentially averting as many as 30 events. Our analysis demonstrates that there is substantial value in using pan-Canadian health services data to evaluate the safety of vaccines. Efforts should be made to develop a pan-Canadian vaccine data source to allow for an earlier evaluation of suspected adverse events following immunization. Full article

(This article belongs to the Section Vaccine Efficacy and Safety)

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17 pages, 616 KiB

Open AccessReview

Hybrid Immunity against SARS-CoV-2 Variants: A Narrative Review of the Literature

by Panagiota Tsagkli, Maria Geropeppa, Ioanna Papadatou and Vana Spoulou

Vaccines 2024, 12(9), 1051; https://doi.org/10.3390/vaccines12091051 (registering DOI) - 14 Sep 2024

Abstract

The emergence of SARS-CoV-2 led to a global health crisis and the burden of the disease continues to persist. The rapid development and emergency authorization of various vaccines, including mRNA-based vaccines, played a pivotal role in mitigating severe illness and mortality. However, rapid [...] Read more.

The emergence of SARS-CoV-2 led to a global health crisis and the burden of the disease continues to persist. The rapid development and emergency authorization of various vaccines, including mRNA-based vaccines, played a pivotal role in mitigating severe illness and mortality. However, rapid viral mutations, leading to several variants of concern, challenged vaccine effectiveness, particularly concerning immune evasion. Research on immunity, both from natural infection and vaccination, revealed that while neutralizing antibodies provide protection against infection, their effect is short-lived. The primary defense against severe COVID-19 is derived from the cellular immune response. Hybrid immunity, developed from a combination of natural infection and vaccination, offers enhanced protection, with convalescent vaccinated individuals showing significantly higher levels of neutralizing antibodies. As SARS-CoV-2 continues to evolve, understanding the durability and breadth of hybrid immunity becomes crucial. This narrative review examines the latest data on humoral and cellular immunity from both natural infection and vaccination, discussing how hybrid immunity could inform and optimize future vaccination strategies in the ongoing battle against COVID-19 and in fear of a new pandemic. Full article

(This article belongs to the Special Issue SARS-CoV-2 Variants, Vaccines, and Immune Responses)

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28 pages, 4868 KiB

Open AccessArticle

A Serum Multi-Parametric Analysis Identifies an Early Innate Immune Signature Associated to Increased Vaccine-Specific Antibody Production and Seroconversion in Simultaneous COVID-19 mRNA and Cell-Based Quadrivalent Influenza Vaccination

by Martina Severa, Daniela Ricci, Marilena Paola Etna, Marzia Facchini, Simona Puzelli, Giorgio Fedele, Egidio Iorio, Giada Cairo, Sara Castrechini, Valentina Ungari, Marco Iannetta, Pasqualina Leone, Mattea Chirico, Maria Elena Pisanu, Barbara Bottazzi, Livia Benedetti, Michela Sali, Remo Bartolomucci, Stefano Balducci, Cecilia Garlanda, Paola Stefanelli, Antonietta Spadea, Anna Teresa Palamara and Eliana Marina Coccia Show full author list Hide full author list

Vaccines 2024, 12(9), 1050; https://doi.org/10.3390/vaccines12091050 (registering DOI) - 13 Sep 2024

Abstract

In this pilot study, a multi-parametric analysis comparing immune responses in sera of adult healthy subjects (HS) or people with type 2 diabetes mellitus (T2D) undergoing the single or simultaneous administration of mRNA-based COVID-19 and cellular quadrivalent inactivated influenza vaccines was conducted. While [...] Read more.

In this pilot study, a multi-parametric analysis comparing immune responses in sera of adult healthy subjects (HS) or people with type 2 diabetes mellitus (T2D) undergoing the single or simultaneous administration of mRNA-based COVID-19 and cellular quadrivalent inactivated influenza vaccines was conducted. While SARS-CoV-2 antibodies remains comparable, influenza antibody titers and seroconversion were significantly higher upon simultaneous vaccination. Magnitude of anti-influenza humoral response closely correlated with an early innate immune signature, previously described for the COVID-19 vaccine, composed of IL-15, IL-6, TNF-α, IFN-γ, CXCL-10 and here extended also to acute-phase protein Pentraxin 3. People with T2D receiving simultaneous vaccination showed a protective response comparable to HS correlating with the early induction of IFN-γ/CXCL10 and a significant reduction of the circulating glucose level due to increased oxidation of glucose digestion and consumption. These data, although preliminary and in-need of validation in larger cohorts, might be exploited to optimize future vaccination in people with chronic disorders, including diabetes. Full article

(This article belongs to the Special Issue Humoral and Cellular Response after Vaccination)

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19 pages, 1650 KiB

Open AccessArticle

Evaluating Nanoparticulate Vaccine Formulations for Effective Antigen Presentation and T-Cell Proliferation Using an In Vitro Overlay Assay

by Dedeepya Pasupuleti, Priyal Bagwe, Amarae Ferguson, Mohammad N. Uddin, Martin J. D’Souza and Susu. M. Zughaier

Vaccines 2024, 12(9), 1049; https://doi.org/10.3390/vaccines12091049 (registering DOI) - 13 Sep 2024

Abstract

Inducing T lymphocyte (T-cell) activation and proliferation with specificity against a pathogen is crucial in vaccine formulation. Assessing vaccine candidates’ ability to induce T-cell proliferation helps optimize formulation for its safety, immunogenicity, and efficacy. Our in-house vaccine candidates use microparticles (MPs) and nanoparticles [...] Read more.

Inducing T lymphocyte (T-cell) activation and proliferation with specificity against a pathogen is crucial in vaccine formulation. Assessing vaccine candidates’ ability to induce T-cell proliferation helps optimize formulation for its safety, immunogenicity, and efficacy. Our in-house vaccine candidates use microparticles (MPs) and nanoparticles (NPs) to enhance antigen stability and target delivery to antigen-presenting cells (APCs), providing improved immunogenicity. Typically, vaccine formulations are screened for safety and immunostimulatory effects using in vitro methods, but extensive animal testing is often required to assess immunogenic responses. We identified the need for a rapid, intermediate screening process to select promising candidates before advancing to expensive and time-consuming in vivo evaluations. In this study, an in vitro overlay assay system was demonstrated as an effective high-throughput preclinical testing method to evaluate the immunogenic properties of early-stage vaccine formulations. The overlay assay’s effectiveness in testing particulate vaccine candidates for immunogenic responses has been evaluated by optimizing the carboxyfluorescein succinimidyl ester (CFSE) T-cell proliferation assay. DCs were overlaid with T-cells, allowing vaccine-stimulated DCs to present antigens to CFSE-stained T-cells. T-cell proliferation was quantified using flow cytometry on days 0, 1, 2, 4, and 6 upon successful antigen presentation. The assay was tested with nanoparticulate vaccine formulations targeting Neisseria gonorrhoeae (CDC F62, FA19, FA1090), measles, H1N1 flu prototype, canine coronavirus, and Zika, with adjuvants including Alhydrogel^® (Alum) and AddaVax™. The assay revealed robust T-cell proliferation in the vaccine treatment groups, with variations between bacterial and viral vaccine candidates. A dose-dependent study indicated immune stimulation varied with antigen dose. These findings highlight the assay’s potential to differentiate and quantify effective antigen presentation, providing valuable insights for developing and optimizing vaccine formulations. Full article

(This article belongs to the Special Issue Advances in the Use of Nanoparticles for Vaccine Platform Development)

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12 pages, 1381 KiB

Open AccessArticle

Trends in Vaccination Coverage among Children Aged 2–6 Years in Tennessee Counties, 2017–2023

by Walid Q. Alali, Qian Huang, Kate Goodin and Adrian Gonzalez-Lozano

Vaccines 2024, 12(9), 1048; https://doi.org/10.3390/vaccines12091048 - 13 Sep 2024

Abstract

Background/Objectives: This study examines trends in county-level vaccination coverage before, during, and after the COVID-19 pandemic among children aged 2–3 and 4–6 years in Tennessee, with a focus on rurality; Methods: Data from the Tennessee Immunization Information System (January 2017 to [...] Read more.

Background/Objectives: This study examines trends in county-level vaccination coverage before, during, and after the COVID-19 pandemic among children aged 2–3 and 4–6 years in Tennessee, with a focus on rurality; Methods: Data from the Tennessee Immunization Information System (January 2017 to September 2023) were analyzed for vaccination coverage in children in both age groups. The study categorized the COVID-19 pandemic into three periods: pre-pandemic (P1: January 2017 to December 2019), stay-at-home (P2: January 2020 to May 2021), and reopening (P3: June 2021 to September 2023). Vaccination trends were stratified by vaccine type, rurality, sex, race and ethnicity; Results: During P1, there were no significant changes in trends of vaccination coverage percentages in both rural and urban counties for both age groups. However, vaccination coverage declined significantly during P2 and P3 compared to P1 for most vaccines, except for influenza, which initially increased but later declined. Rural counties experienced a more pronounced decline compared to urban counties during P2 and P3 for both age groups. Within rural and urban counties, vaccination coverage was higher among white children compared to black children, and among non-Hispanic compared to Hispanic children. There were higher coverage percentages in age group 4–6 for all vaccines, except for influenza, compared to 2–3 year group; Conclusions: The COVID-19 pandemic has exacerbated disparities in childhood vaccination coverage, particularly in rural areas. These findings highlight the need for targeted public health interventions to address barriers to vaccination and ensure equitable access to vaccines for all children. Full article

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10 pages, 5072 KiB

Open AccessArticle

Construction of Recombinant Marek’s Disease Virus Co-Expressing VP1 and VP2 of Chicken Infectious Anemia Virus

by Kai Li, Yongzhen Liu, Changjun Liu, Yanping Zhang, Hongyu Cui, Xiaole Qi, Jiayong Zhang, Jia Xu, Suyan Wang, Yuntong Chen, Yulu Duan, Yulong Gao and Xiaomei Wang

Vaccines 2024, 12(9), 1047; https://doi.org/10.3390/vaccines12091047 - 13 Sep 2024

Abstract

The chicken infectious anemia virus (CIAV) has been reported in major poultry-producing countries and poses a significant threat to the poultry industry worldwide. In this study, two Marek’s disease virus (MDV) recombinants, rMDV-CIAV-1 and rMDV-CIAV-2, were generated by inserting the CIAV VP1 and [...] Read more.

The chicken infectious anemia virus (CIAV) has been reported in major poultry-producing countries and poses a significant threat to the poultry industry worldwide. In this study, two Marek’s disease virus (MDV) recombinants, rMDV-CIAV-1 and rMDV-CIAV-2, were generated by inserting the CIAV VP1 and VP2 genes into the MDV vaccine strain 814 at the US2 site using the fosmid-based rescue system. For rMDV-CIAV-1, an internal ribosome entry site was inserted between VP1 and VP2, so that both proteins were produced from a single open reading frame. In rMDV-CIAV-2, VP1 and VP2 were cloned into different open reading frames and inserted into the MDV genome. The recombinant viruses simultaneously expressed VP1 and VP2 in infected chicken embryo fibroblasts and exhibited growth kinetics similar to those of the parent MDV. The two recombinant viruses induced antibodies against CIAV in chickens. A single dose of the recombinant viruses provided strong protection against CIAV-induced anemia in chickens. These recombinant VP1- and VP2-expressing MDVs are potential vaccines against CIAV in chickens. Full article

(This article belongs to the Special Issue Vaccines for Chicken)

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11 pages, 2502 KiB

Open AccessArticle

Dupilumab and House Dust Mite Immunotherapy in Patients with Atopic Dermatitis: A Preliminary Study

by Agnieszka Bogacz-Piaseczyńska, Andrzej Bożek, Magdalena Krupka-Olek, Aleksandra Kawczyk-Krupka, Jolanta Zalejska-Fiolka and Giorgio Walter Canonica

Vaccines 2024, 12(9), 1046; https://doi.org/10.3390/vaccines12091046 - 13 Sep 2024

Abstract

Background: Severe atopic dermatitis (AD) is a complex disease requiring systemic treatment. This study aimed to assess the effectiveness of combined therapy consisting of dupilumab and sublingual dust mite allergen immunotherapy (SLIT-HDM) in patients with severe AD and HDM allergies. Methods: Patients diagnosed [...] Read more.

Background: Severe atopic dermatitis (AD) is a complex disease requiring systemic treatment. This study aimed to assess the effectiveness of combined therapy consisting of dupilumab and sublingual dust mite allergen immunotherapy (SLIT-HDM) in patients with severe AD and HDM allergies. Methods: Patients diagnosed with severe AD were included in this randomised, placebo-controlled, double-blind 12-month trial; they received SLIT for HDMs and/or dupilumab for 12 months and were compared with patients on cyclosporine. The primary outcomes for the treatment arms were changes in the Eczema Area and Severity Index (EASI), body surface area (%BSA), and Investigator Global Assessment (IsGA) over 12 months. The secondary outcomes were the proportion of patients who achieved IsGA success and reduced medication scores. Results: Significant improvements were observed in all analysed groups after 12 months of therapy based on the EASI, %BSA, and IsGA. However, the most substantial changes were observed in the groups treated with dupilumab or a combination of SLIT-HDM and dupilumab. Additionally, the proportion of patients who achieved an IsGA reduction was significantly greater in the group receiving combination therapy than in the other groups (9/14 [64% of the group receiving SLIT-HDM] vs. 11/14 [73% of the group receiving dupilumab] vs. 15/17 [88% of the group receiving dupilumab and SLIT-HDM] vs. 7/13 [53% of the group receiving cyclosporine]) (p < 0.05). Conclusions: In patients with severe AD and HDM allergies, combination treatment with dupilumab and allergen immunotherapy for HDMs may increase the therapeutic benefit over treatment with these methods separately. Full article

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23 pages, 2059 KiB

Open AccessArticle

Cost-Effectiveness Analysis of Routine Childhood Immunization with 20-Valent versus 15-Valent Pneumococcal Conjugate Vaccines in Germany

by Min Huang, Jessica P. Weaver, Elamin Elbasha, Thomas Weiss, Natalie Banniettis, Kristen Feemster, Meghan White and Matthew S. Kelly

Vaccines 2024, 12(9), 1045; https://doi.org/10.3390/vaccines12091045 (registering DOI) - 12 Sep 2024

Abstract

This study aimed to evaluate the cost-effectiveness of routine childhood immunization with the 20-valent pneumococcal conjugate vaccine (PCV20) in a four-dose regimen (3 + 1 schedule) versus the 15-valent PCV (PCV15/V114) in a three-dose regimen (2 + 1) in Germany. The study utilized [...] Read more.

This study aimed to evaluate the cost-effectiveness of routine childhood immunization with the 20-valent pneumococcal conjugate vaccine (PCV20) in a four-dose regimen (3 + 1 schedule) versus the 15-valent PCV (PCV15/V114) in a three-dose regimen (2 + 1) in Germany. The study utilized a decision-analytic Markov model to estimate lifetime costs and effectiveness outcomes for a single birth cohort in Germany. The model tracked the incidence of acute pneumococcal infections and long-term pneumococcal meningitis sequelae for both vaccination strategies. The vaccine effectiveness data were derived from published clinical trials and observational studies of PCV7 and PCV13. Indirect effects, such as herd protection and serotype replacement, were included in the model. The model adopted a societal perspective, including direct medical, direct non-medical, and indirect costs. Scenario and sensitivity analyses were performed. In the base case, PCV20 prevented more pneumococcal disease cases and deaths, with an expected gain of 96 quality-adjusted life years (QALYs) compared to V114. However, PCV20 was associated with a total incremental cost of EUR 48,358,424, resulting in an incremental cost-effectiveness ratio (ICER) of EUR 503,620/QALY. Most of the scenario and sensitivity analyses estimated that the ICER for PCV20 exceeded EUR 150,000/QALY. Routine childhood immunization with PCV20 instead of V114 may not be an economically efficient use of healthcare resources in Germany. Full article

(This article belongs to the Section Vaccines against Infectious Diseases)

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19 pages, 586 KiB

Open AccessReview

Recent Occurrence, Diversity, and Candidate Vaccine Virus Selection for Pandemic H5N1: Alert Is in the Air

by Yordanka Medina-Armenteros, Daniela Cajado-Carvalho, Ricardo das Neves Oliveira, Milena Apetito Akamatsu and Paulo Lee Ho

Vaccines 2024, 12(9), 1044; https://doi.org/10.3390/vaccines12091044 - 12 Sep 2024

Abstract

The prevalence of the highly pathogenic avian influenza virus H5N1 in wild birds that migrate all over the world has resulted in the dissemination of this virus across Asia, Europe, Africa, North and South America, the Arctic continent, and Antarctica. So far, H5N1 [...] Read more.

The prevalence of the highly pathogenic avian influenza virus H5N1 in wild birds that migrate all over the world has resulted in the dissemination of this virus across Asia, Europe, Africa, North and South America, the Arctic continent, and Antarctica. So far, H5N1 clade 2.3.4.4.b has reached an almost global distribution, with the exception of Australia and New Zealand for autochthonous cases. H5N1 clade 2.3.4.4.b, derived from the broad-host-range A/Goose/Guangdong/1/96 (H5N1) lineage, has evolved, adapted, and spread to species other than birds, with potential mammal-to-mammal transmission. Many public health agencies consider H5N1 influenza a real pandemic threat. In this sense, we analyzed H5N1 hemagglutinin sequences from recent outbreaks in animals, clinical samples, antigenic prototypes of candidate vaccine viruses, and licensed human vaccines for H5N1 with the aim of shedding light on the development of an H5N1 vaccine suitable for a pandemic response, should one occur in the near future. Full article

(This article belongs to the Special Issue Immunity to Influenza Viruses and Vaccines)

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18 pages, 319 KiB

Open AccessReview

HIV Vaccine Development at a Crossroads: New B and T Cell Approaches

by Ramesh Govindan and Kathryn E. Stephenson

Vaccines 2024, 12(9), 1043; https://doi.org/10.3390/vaccines12091043 - 12 Sep 2024

Abstract

Despite rigorous scientific efforts over the forty years since the onset of the global HIV pandemic, a safe and effective HIV-1 vaccine remains elusive. The challenges of HIV vaccine development have proven immense, in large part due to the tremendous sequence diversity of [...] Read more.

Despite rigorous scientific efforts over the forty years since the onset of the global HIV pandemic, a safe and effective HIV-1 vaccine remains elusive. The challenges of HIV vaccine development have proven immense, in large part due to the tremendous sequence diversity of HIV and its ability to escape from antiviral adaptive immune responses. In recent years, several phase 3 efficacy trials have been conducted, testing a similar hypothesis, e.g., that non-neutralizing antibodies and classical cellular immune responses could prevent HIV-1 acquisition. These studies were not successful. As a result, the field has now pivoted to bold novel approaches, including sequential immunization strategies to drive the generation of broadly neutralizing antibodies and human CMV-vectored vaccines to elicit MHC-E-restricted CD8+ T cell responses. Many of these vaccine candidates are now in phase 1 trials, with early promising results. Full article

(This article belongs to the Special Issue T-cell Immunity and Viral Pathogenicity on Vaccine Efficacy)

16 pages, 1961 KiB

Open AccessArticle

Post-Pandemic Maternity Care Planning for Vaccination: A Qualitative Study of the Experiences of Women, Partners, Health Care Professionals, and Policy Makers in the United Kingdom

by Tisha Dasgupta, Harriet Boulding, Abigail Easter, Tania Sutedja, Asma Khalil, Hiten D. Mistry, Gillian Horgan, Aricca D. Van Citters, Eugene C. Nelson, Peter von Dadelszen, Emma L. Duncan, The RESILIENT Study Group, Sergio A. Silverio and Laura A. Magee

Vaccines 2024, 12(9), 1042; https://doi.org/10.3390/vaccines12091042 - 11 Sep 2024

Abstract

Maternal vaccination during pregnancy, in general and against COVID-19 infection, offers protection to both mother and baby, but uptake remains suboptimal. This study aimed to explore the perceptions regarding COVID-19 vaccination in pregnancy, particularly for marginalised populations and those living with social or [...] Read more.

Maternal vaccination during pregnancy, in general and against COVID-19 infection, offers protection to both mother and baby, but uptake remains suboptimal. This study aimed to explore the perceptions regarding COVID-19 vaccination in pregnancy, particularly for marginalised populations and those living with social or medical complexity. A total of 96 semi-structured in-depth interviews were conducted with 40 women, 15 partners, 21 HCPs, and 20 policy makers, across all four nations of the United Kingdom (UK), discussing their lived experience of utilising, delivering, or developing policy for COVID-19 vaccination in pregnancy during the pandemic. Three themes were derived: (1) historical and social context, (2) communication of information and guidance, and (3) appraisal and action. Together these captured the participants’ legacy of mistrust in drugs during pregnancy; prior positive experiences; concerns about missing information, conflicting information, or false information about COVID-19 vaccines; and confusing guidance for pregnant women. The final theme describes the participants’ behaviour and actions undertaken consequent to their experiences and the available information. The findings suggest efforts to improve COVID-19 vaccination in pregnancy may be best focused on personalised communication of information. A trusting relationship and prior positive experiences with other vaccines, both in and outside of pregnancy, positively influenced perceptions of COVID-19 vaccination. Full article

(This article belongs to the Special Issue Trust, Willingness, and Associated Factors towards COVID-19 Vaccine Uptake)

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12 pages, 255 KiB

Open AccessArticle

Potential Association between Shift Work and Serologic Response to Hepatitis B Vaccination among Manufacturing Workers in Republic of Korea

by Si-Ho Kim and Chang-Ho Chae

Vaccines 2024, 12(9), 1041; https://doi.org/10.3390/vaccines12091041 - 11 Sep 2024

Abstract

(1) Background: Shift work can affect physical health and the immune system by altering the body’s circadian rhythms. This study investigated the factors associated with the hepatitis B virus (HBV) vaccination response in manufacturing workers, classified by whether they engaged in shift work [...] Read more.

(1) Background: Shift work can affect physical health and the immune system by altering the body’s circadian rhythms. This study investigated the factors associated with the hepatitis B virus (HBV) vaccination response in manufacturing workers, classified by whether they engaged in shift work or not. (2) Methods: This retrospective observational study was conducted among adults employed at two manufacturing companies. Those with negative initial hepatitis B surface antibody (HBsAb) levels before vaccination and who subsequently received a three-dose series of HBV vaccine were enrolled. Hepatitis B surface antibodies were examined for 3 years after the first dose. The endpoint of this study was the failure of a seroprotective anti-HB response after vaccination (HBsAb < 10 mIU/mL). Binary logistic regression models were used to analyze factors associated with response failures. (3) Results: Of the 1103 eligible subjects, 337 (30.6%) were shift workers. The failure rate was numerically higher in the shift workers (9.2%) than in the non-shift workers (7.9%), without statistical significance (p = 0.405). However, after adjustment with the binary logistic regression models, the shift workers had a statistically significantly higher rate of response failures than the non-shift workers (odds ratio 2.87; 95% confidence interval 1.64–5.05, p < 0.001), as did males, older workers, those with a low initial anti-HB titer, those with a vitamin D deficiency, and current smokers. (4) Conclusions: Our findings suggest a possible association between shift work and the serologic responses to HBV vaccination. Novel strategies for vaccination should be considered for shift workers. Full article

(This article belongs to the Special Issue Effectiveness and Safety of Vaccines in Special Populations)

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20 pages, 7663 KiB

Open AccessArticle

Changes in Phenotypic and Molecular Features of Naïve and Central Memory T Helper Cell Subsets following SARS-CoV-2 Vaccination

by Mia Mosavie, Jennifer Rynne, Matthew Fish, Peter Smith, Aislinn Jennings, Shivani Singh, Jonathan Millar, Heli Harvala, Ana Mora, Fotini Kaloyirou, Alexandra Griffiths, Valerie Hopkins, Charlotte Washington, Lise J. Estcourt, David Roberts and Manu Shankar-Hari

Vaccines 2024, 12(9), 1040; https://doi.org/10.3390/vaccines12091040 - 11 Sep 2024

Abstract

Molecular changes in lymphocytes following SARS-CoV-2 vaccination are incompletely understood. We hypothesized that studying the molecular (transcriptomic, epigenetic, and T cell receptor (TCR) repertoire) changes in CD4⁺ T cells following SARS-CoV-2 vaccination could inform protective mechanisms and refinement of future vaccines. We [...] Read more.

Molecular changes in lymphocytes following SARS-CoV-2 vaccination are incompletely understood. We hypothesized that studying the molecular (transcriptomic, epigenetic, and T cell receptor (TCR) repertoire) changes in CD4⁺ T cells following SARS-CoV-2 vaccination could inform protective mechanisms and refinement of future vaccines. We tested this hypothesis by reporting alterations in CD4⁺ T cell subsets and molecular features of CD4⁺ naïve and CD4⁺ central memory (CM) subsets between the unvaccinated and vaccinated groups. Compared with the unvaccinated, the vaccinated had higher HLA-DR expression in CD4⁺ T subsets, a greater number of differentially expressed genes (DEGs) that overlapped with key differentially accessible regions (DARs) along the chromatin linked to inflammasome activation, translation, regulation (of apoptosis, inflammation), and significant changes in clonal architecture beyond SARS-CoV-2 specificity. Several of these differences were more pronounced in the CD4⁺CM subset. Taken together, our observations imply that the COVID-19 vaccine exerts its protective effects via modulation of acute inflammation to SARS-CoV-2 challenge. Full article

(This article belongs to the Special Issue The 2nd Edition: Cellular and Humoral Immunity after COVID-19 Vaccination)

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13 pages, 8403 KiB

Open AccessArticle

Neutralizing Antibodies against 10 SARS-CoV-2 Variants at Two Years Post-COVISHIELD Vaccination with Special Reference to Omicron Subvariants and Booster Administration

by Rajashree Patil, Sonali Palkar, Akhileshchandra Mishra and Vidya Arankalle

Vaccines 2024, 12(9), 1039; https://doi.org/10.3390/vaccines12091039 - 11 Sep 2024

Abstract

To study the durability of neutralizing antibodies (NAbs) against ten SARS-CoV-2 variants among COVISHIELD vaccine recipients from Pune, India, 184 vaccinee samples with (pre-positives) or without (pre-negatives) prior antibody positivity were evaluated. To estimate NAb levels, a validated ten-plex MSD ACE2 neutralization assay [...] Read more.

To study the durability of neutralizing antibodies (NAbs) against ten SARS-CoV-2 variants among COVISHIELD vaccine recipients from Pune, India, 184 vaccinee samples with (pre-positives) or without (pre-negatives) prior antibody positivity were evaluated. To estimate NAb levels, a validated ten-plex MSD ACE2 neutralization assay was used. NAbs against Alpha, Beta, Delta, and Omicron/subvariants were assessed at 1 month (PD2-1) and 6 months (PD2-6) post-vaccination, post-booster dose, and 2 years (2Y) post-vaccination. In pre-negatives, the seropositivity declined from PD2-1 to PD2-6 for all variants (Omicron variants: 14–54% to 0%; non-Omicron variants: 66–100% to 8–44%). In pre-positives, the decline in seropositivity from PD2-1 to PD2-6 was seen only for Omicron variants (14–39%). At PD2-6, a significant reduction in NAb levels was observed in all vaccinees against all the variants. Irrespective of prior exposure, the diminished anti-variant antibody levels at PD2-6 increased significantly following the administration of the booster. In conclusion, the COVISHIELD vaccine booster dose did provide cross-neutralizing antibodies against broad-range SARS-CoV-2 variants with improved durability up to [16 (15–18)] months post-booster dose and two years post-vaccination. Full article

(This article belongs to the Special Issue COVID Vaccines: Design, Development, and Immune Response Studies)

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15 pages, 261 KiB

Open AccessReview

Enhancing COVID-19 Vaccination Awareness and Uptake in the Post-PHEIC Era: A Narrative Review of Physician-Level and System-Level Strategies

by Kay Choong See

Vaccines 2024, 12(9), 1038; https://doi.org/10.3390/vaccines12091038 - 11 Sep 2024

Abstract

Following the World Health Organization’s declaration that the COVID-19 pandemic is no longer a public health emergency of international concern (PHEIC), COVID-19 remains an ongoing threat to human health and healthcare systems. Vaccination plays a crucial role in reducing the disease’s incidence, mitigating [...] Read more.

Following the World Health Organization’s declaration that the COVID-19 pandemic is no longer a public health emergency of international concern (PHEIC), COVID-19 remains an ongoing threat to human health and healthcare systems. Vaccination plays a crucial role in reducing the disease’s incidence, mitigating its severity, and limiting transmission, contributing to long-term public health resilience. However, incomplete vaccination coverage and vaccine hesitancy exist. This narrative review investigates strategies at the system and physician levels aimed at sustaining awareness and uptake of COVID-19 vaccination in a post-PHEIC era. Through an examination of the existing literature, this review explores the effectiveness of diverse approaches utilized by healthcare systems and individual providers. These approaches address every component of the 5C model of vaccine hesitancy: confidence, complacency, constraints/convenience, calculation, and collective responsibility. Physician-level approaches include appropriate message framing, persuasive communication containing safety and personal/social benefit information, sharing of personal stories, creating a safe space for discussion, harnessing co-administration with annual influenza vaccines, and use of decision aids and visual messages. System-level approaches include messaging, mass media for health communication, on-site vaccine availability, pharmacist delivery, healthcare protocol integration, incentives, and chatbot use. Full article

(This article belongs to the Special Issue Knowledge, Attitudes and Associated Factors Surrounding COVID-19 Vaccination)

19 pages, 6886 KiB

Open AccessArticle

GSK-3β in Dendritic Cells Exerts Opposite Functions in Regulating Cross-Priming and Memory CD8 T Cell Responses Independent of β-Catenin

by Chunmei Fu, Jie Wang, Tianle Ma, Congcong Yin, Li Zhou, Björn E. Clausen, Qing-Sheng Mi and Aimin Jiang

Vaccines 2024, 12(9), 1037; https://doi.org/10.3390/vaccines12091037 - 10 Sep 2024

Abstract

GSK-3β plays a critical role in regulating the Wnt/β-catenin signaling pathway, and manipulating GSK-3β in dendritic cells (DCs) has been shown to improve the antitumor efficacy of DC vaccines. Since the inhibition of GSK-3β leads to the activation of β-catenin, we hypothesize that [...] Read more.

GSK-3β plays a critical role in regulating the Wnt/β-catenin signaling pathway, and manipulating GSK-3β in dendritic cells (DCs) has been shown to improve the antitumor efficacy of DC vaccines. Since the inhibition of GSK-3β leads to the activation of β-catenin, we hypothesize that blocking GSK-3β in DCs negatively regulates DC-mediated CD8 T cell immunity and antitumor immunity. Using CD11c-GSK-3β^−/− conditional knockout mice in which GSK-3β is genetically deleted in CD11c-expressing DCs, we surprisingly found that the deletion of GSK-3β in DCs resulted in increased antitumor immunity, which contradicted our initial expectation of reduced antitumor immunity due to the presumed upregulation of β-catenin in DCs. Indeed, we found by both Western blot and flow cytometry that the deletion of GSK-3β in DCs did not lead to augmented expression of β-catenin protein, suggesting that GSK-3β exerts its function independent of β-catenin. Supporting this notion, our single-cell RNA sequencing (scRNA-seq) analysis revealed that GSK-3β-deficient DCs exhibited distinct gene expression patterns with minimally overlapping differentially expressed genes (DEGs) compared to DCs with activated β-catenin. This suggests that the deletion of GSK-3β in DCs is unlikely to lead to upregulation of β-catenin at the transcriptional level. Consistent with enhanced antitumor immunity, we also found that CD11c-GSK-3β^−/− mice exhibited significantly augmented cross-priming of antigen-specific CD8 T cells following DC-targeted vaccines. We further found that the deletion of GSK-3β in DCs completely abrogated memory CD8 T cell responses, suggesting that GSK-3β in DCs also plays a negative role in regulating the differentiation and/or maintenance of memory CD8 T cells. scRNA-seq analysis further revealed that although the deletion of GSK-3β in DCs positively regulated transcriptional programs for effector differentiation and function of primed antigen-specific CD8 T cells in CD11c-GSK-3β^−/− mice during the priming phase, it resulted in significantly reduced antigen-specific memory CD8 T cells, consistent with diminished memory responses. Taken together, our data demonstrate that GSK-3β in DCs has opposite functions in regulating cross-priming and memory CD8 T cell responses, and GSK-3β exerts its functions independent of its regulation of β-catenin. These novel insights suggest that targeting GSK-3β in cancer immunotherapies must consider its dual role in CD8 T cell responses. Full article

(This article belongs to the Special Issue Vaccines Targeting Dendritic Cells)

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14 pages, 1775 KiB

Open AccessArticle

Safety and Immunogenicity of a Carbohydrate Fatty Acid Monosulphate Ester Adjuvant Combined with a Low-Dose Quadrivalent Split-Virion Inactivated Influenza Vaccine: A Randomised, Observer-Blind, Active-Controlled, First-in-Human, Phase 1 Study

by Valentino D’Onofrio, Sharon Porrez, Bart Jacobs, Azhar Alhatemi, Fien De Boever, Gwenn Waerlop, Els Michels, Francesca Vanni, Alessandro Manenti, Geert Leroux-Roels, Peter Paul Platenburg, Luuk Hilgers and Isabel Leroux-Roels

Vaccines 2024, 12(9), 1036; https://doi.org/10.3390/vaccines12091036 - 10 Sep 2024

Abstract

Seasonal influenza vaccine effectiveness is low. Carbohydrate fatty acid monosulphate ester (CMS), a new oil-in-water adjuvant, has proven potency in animal models with suggested capacity for dose-sparing. The objective was to evaluate safety and immunogenicity of CMS when added to a low-dose influenza [...] Read more.

Seasonal influenza vaccine effectiveness is low. Carbohydrate fatty acid monosulphate ester (CMS), a new oil-in-water adjuvant, has proven potency in animal models with suggested capacity for dose-sparing. The objective was to evaluate safety and immunogenicity of CMS when added to a low-dose influenza vaccine (QIV) in humans. In a randomised, double-blind, active-controlled, first-in-human study, sixty participants (18–50 years) received either 0.5 mg CMS or 2 mg CMS with 1/5th dose QIV, or a full dose QIV without CMS. Adverse events (AE) were monitored until 7 days post-vaccination. Haemagglutinin inhibition (HI) titres in serum and CD4+ T cells in PBMCs were determined at day 0, 7, 28, and 180. Mean age was 37.6 (±10.1) years and 42/60 (70.0%) were female. Pain at injection site (42/60, 86.7%) and headache (34/60, 56.7%) were reported most and more frequently in the 2 mg CMS group. HI titres and the frequency of influenza specific CD4+ T cells were equal across strains for the three cohorts on all visits, increased until day 28 and decreased at day 180 to values higher than baseline. CMS was safe in humans. Humoral and cell-mediated immunogenicity was similar across vaccines, even with 1/5th antigen dose. CMS can have beneficial implications in low-resource settings or in a pandemic context. Full article

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