Shingrix: The New Adjuvanted Recombinant Herpes Zoster Vaccine

Real-world data on the use of the Shingrix vaccine among patients with inflammatory arthritis and risk of cardiovascular events following herpes zoster

BACKGROUND

Risk of cardiovascular events may increase after herpes zoster; therefore, American College of Rheumatology guidelines strongly recommend vaccination against herpes zoster in patients aged ≥ 18 years with rheumatic and musculoskeletal diseases taking immunosuppressive medications. Here, we investigated the effectiveness of Shingrix among patients with inflammatory arthritis and estimated the post-herpes zoster risk of cardiovascular events.

METHODS

In this retrospective observational cohort study, data were obtained from the Optum™ Clinformatics™ Data Mart on patients aged ≥ 18 years with rheumatoid arthritis, psoriatic arthritis, or axial spondyloarthritis. The proportions of patients receiving any Shingrix dose, a second dose, and a second dose within 6, 9, and 12 months were calculated. Incidence of herpes zoster following inflammatory arthritis diagnosis was reported. Vaccine effectiveness was calculated as (1 - incidence rate ratio of herpes zoster) × 100. Relative risk of cardiovascular events was assessed independently in the 30-, 45-, 60-, and 90-day periods post-herpes zoster in a subgroup of patients who experienced cardiovascular events.

RESULTS

The final cohort included 132,672 patients with inflammatory arthritis. Mean age was 60.4 years, 71.9% were female, and 80.0% were diagnosed with rheumatoid arthritis. Overall, 28,690 (21.6%) patients received ≥ 1 Shingrix dose, of whom only 73.2% received a second dose. Of those receiving a second dose, 17,598 (83.8%) received it within the recommended 2-6 months after the first. Herpes zoster occurred in 4,342 (3.3%) patients, of which 360 cases occurred after Shingrix vaccination. The incidence rate (95% confidence interval) of herpes zoster per 1,000 person-years was 7.41 (6.64, 8.17) after any Shingrix vaccination vs. 14.76 (14.30, 15.22) without vaccination (crude vaccine effectiveness: 50%). The risk of venous thromboembolic events was elevated in the 60-90 days post-herpes zoster; no significantly increased risk was observed for any other cardiovascular events.

CONCLUSIONS

This study showed that the effectiveness of Shingrix in patients with inflammatory arthritis on immunomodulatory treatment was 50%, and the risk of venous thromboembolic events was increased in the 60-90 days after herpes zoster, supporting the recommendation that adults with inflammatory arthritis should receive vaccination against herpes zoster to reduce the risk of such events.

Herpes zoster infection in patients with inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) are at increased risk of herpes zoster (HZ), particularly those receiving immunosuppressive treatments such as corticosteroids, thiopurines, and biologics, which elevate the likelihood of varicella-zoster virus reactivation. Despite this, vaccination rates among patients with IBD remain low. Shingrix, a recombinant zoster vaccine, is generally preferred because of its high efficacy (> 90%) and safety profile in immunocompromised individuals, unlike the live attenuated zoster vaccine (Zostavax). This review underscores the importance of HZ vaccination for patients aged ≥ 50 years, as well as for younger patients receiving high-risk therapies such as JAK inhibitors. Tailored vaccination strategies based on individual risk factors, including disease severity, medication use, and ethnicity, may enhance prevention. Given the higher incidence of HZ in certain populations, such as those in Korea, vaccination recommendations should be adapted accordingly. Further research is needed to evaluate the long-term effectiveness of Shingrix in younger patients with IBD to ensure sustained protection and prevent complications, such as postherpetic neuralgia.

Development of a New Vaccine Adjuvant System Based on the Combination of the Synthetic TLR4 Agonist FP20 and a Synthetic QS-21 Variant

In this study, we formulated an alternative to AS01b by combining FP20, a synthetic TLR4 agonist, and QS21v, a minimal saponin adjuvant, aiming to improve the vaccine efficacy and stability. The phase transition temperature of FP20 was determined by using differential scanning calorimetry to be 43.9 °C, providing a foundation for the formulation process. The coformulation was prepared using a dry film method for even adjuvant distribution. Characterization by dynamic light scattering and nanoparticle tracking analysis revealed a uniform particle size distribution of ∼120 nm. Cryogenic electron microscopy (CryoEM) revealed nanosized interactions between FP20 and QS21v, forming stable structures that likely enhanced the antigen presentation and immune activation. These physicochemical properties contributed to a robust in vivo synergy, where the coformulation elicited significantly higher antigen-specific antibody titers compared to individual adjuvants. These findings suggest that the FP20+QS21v coformulation provides a potent, stable, and safer alternative to traditional adjuvants, enhancing both vaccine efficacy and immunogenicity.

Glycoprotein E-Displaying Nanoparticles Induce Robust Neutralizing Antibodies and T-Cell Response against Varicella Zoster Virus

The Varicella zoster virus (VZV), responsible for both varicella (chickenpox) and herpes zoster (shingles), presents significant global health challenges. While primary VZV infection primarily affects children, leading to chickenpox, reactivation in later life can result in herpes zoster and associated post-herpetic neuralgia, among other complications. Vaccination remains the most effective strategy for VZV prevention, with current vaccines largely based on the attenuated vOka strains. Although these vaccines are generally effective, they can induce varicella-like rashes and have sparked concerns regarding cell virulence. As a safer alternative, subunit vaccines circumvent these issues. In this study, we developed a nanoparticle-based vaccine displaying the glycoprotein E (gE) on ferritin particles using the SpyCatcher/SpyTag system, termed FR-gE. This FR-gE nanoparticle antigen elicited substantial gE-specific binding and VZV-neutralizing antibody responses in BALB/c and C57BL/6 mice-responses that were up to 3.2-fold greater than those elicited by the subunit gE while formulated with FH002C, aluminum hydroxide, or a liposome-based XUA01 adjuvant. Antibody subclass analysis revealed that FR-gE produced comparable levels of IgG1 and significantly higher levels of IgG2a compared to subunit gE, indicating a Th1-biased immune response. Notably, XUA01-adjuvanted FR-gE induced a significant increase in neutralizing antibody response compared to the live attenuated varicella vaccine and recombinant vaccine, Shingrix. Furthermore, ELISPOT assays demonstrated that immunization with FR-gE/XUA01 generated IFN-γ and IL-2 levels comparable to those induced by Shingrix. These findings underscore the potential of FR-gE as a promising immunogen for the development of varicella and herpes zoster vaccines.

Development of semisynthetic saponin immunostimulants

Many natural saponins demonstrate immunostimulatory adjuvant activities, but they also have some inherent drawbacks that limit their clinical use. To overcome these limitations, extensive structure-activity-relationship (SAR) studies have been conducted. The SAR studies of QS-21 and related saponins reveal that their respective fatty side chains are crucial for potentiating a strong cellular immune response. Replacing the hydrolytically unstable ester side chain in the C28 oligosaccharide domain with an amide side chain in the same domain or in the C3 branched trisaccharide domain is a viable approach for generating robust semisynthetic saponin immunostimulants. Given the striking resemblance of natural momordica saponins (MS) I and II to the deacylated Quillaja Saponaria (QS) saponins (e.g., QS-17, QS-18, and QS-21), incorporating an amide side chain into the more sustainable MS, instead of deacylated QS saponins, led to the discovery of MS-derived semisynthetic immunostimulatory adjuvants VSA-1 and VSA-2. This review focuses on the authors' previous work on SAR studies of QS and MS saponins.

Anti-Herpes Zoster Vaccination of Fragile Patients in Hospital Setting: A Nudge Intervention in Italy

BACKGROUND

A nudge intervention against Herpes Zoster, created and implemented in Italy, is presented in order to administer the Shingrix vaccine on a sample of frail patients, as required by the National Prevention Plan. Individual and contextual factors associated with vaccine adherence were investigated.

METHOD

300 frail adult subjects underwent a full vaccine cycle with recombinant-Shingrix vaccine (RZV vaccine). Hospital Presidia of the Salerno University Hospital Authority, a Hospital Presidium of the Salerno Local Health Authority, and the Public Health Laboratory of the University of Salerno (Campania) participated in the intervention. An ad hoc questionnaire was administered with the following scales: EQ-5D, PSS-10, MSPSS, and representations of HZ and its consequences.

RESULTS

Some variables, such as peer support, doctor-patient relationship, level of education, and perception of health, are important in vaccine adherence and information processing. The following factors emerged from the factor analysis: Trust in collective knowledge and collective responsibility (F1); beliefs about virus risk and vaccine function (F2); information about virus and symptomatology (F3); and vaccine distrust (F4). Factor 4 correlates negatively with social support indices (R = -0.363; p < 0.001). There is a significant relationship between factor 3 and satisfaction with national information campaigns (F = 3.376; gdl = 5; p-value = 0.006).

CONCLUSIONS

Future vaccination campaigns should be built with the aim of personalizing information and developing contextualized strategies, starting from understanding the stakeholders involved, cultural contexts, and organizational settings.

Chemical and biological characterization of vaccine adjuvant QS-21 produced via plant cell culture

Many vaccines, including those using recombinant antigen subunits, rely on adjuvant(s) to enhance the efficacy of the host immune responses. Among the few adjuvants clinically approved, QS-21, a saponin-based immunomodulatory molecule isolated from the tree bark of Quillaja saponaria (QS) is used in complex formulations in approved effective vaccines. High demand of the QS raw material as well as manufacturing scalability limitation has been barriers here. We report for the first-time successful plant cell culture production of QS-21 having structural, chemical, and biologic, properties similar to the bark extracted product. These data ensure QS-21 and related saponins are broadly available and accessible to drug developers.

Development of Shingles on Tofacitinib Despite Completion of Recombinant Varicella-Zoster Virus Vaccine Series

Shingles, also known as herpes zoster, is caused by the reactivation of the varicella-zoster virus (VZV). The risk of developing shingles increases with age, as well as in patients with weakened immune systems. Tofacitinib is a reversible Janus kinase inhibitor that suppresses the immune system and is used to treat autoimmune diseases, such as ulcerative colitis. Recombinant VZV vaccine is recommended for individuals taking tofacitinib and is highly effective at reducing the risk of shingles. This case report describes a patient with severe, refractory ulcerative colitis who developed shingles while on tofacitinib, despite prior vaccination with the recombinant VZV vaccine.

Reactivation of Herpes Zoster in a Young Patient With Multiple Sclerosis Under Dimethyl Fumarate Treatment and Normal Lymphocyte Subsets Count: A Case Report

Herpes zoster (HZ) infection results from the reactivation of the varicella-zoster virus (VZV), which remains dormant in the dorsal root ganglia after an initial chickenpox infection. Although HZ appears more common in people with multiple sclerosis (MS) than expected in the general population, few studies have investigated this association, particularly with a normal absolute lymphocyte count (ALC). Additionally, no reported cases have discussed the clinical presentation of such patients. This report describes the case of a 26-year-old female with a known history of relapsing-remitting MS on dimethyl fumarate (DMF) treatment. She presented with a history of painful erythematous blisters, diagnosed as acute HZ infection with a normal ALC. This case provides evidence that warrants further research and attention to the management of patients with MS receiving DMF, particularly regarding infectious risks. It highlights the importance of pharmacovigilance and the potential benefits of VZV and HZ immunization in DMF recipients.

Public Knowledge, Attitude, and Practice Toward Herpes Zoster Vaccination in Saudi Arabia

Introduction Herpes zoster (HZ) is a viral infection that occurs due to the reactivation of the varicella-zoster virus (VZV). Reactivation of the latent virus causes a painful dermatomal rash that is typical in HZ, which is frequently accompanied by post-herpetic neuralgia (PHN). Although HZ negatively impacts individuals' quality of life, vaccination has been shown to reduce the incidence of HZ and PHN and reduce the severity of the disease in the event of a breakthrough. Nonetheless, several studies have shown a low level of knowledge and poor practices regarding HZ and its vaccine. However, only two studies on this issue have been conducted in the Middle East. This study aimed to assess the level of knowledge, attitudes, and practices toward HZ vaccinations among the Saudi population aged 50 years and older. Methods A cross-sectional observational study was conducted from December 2022 to July 2023 involving citizens aged 50 years and older in Saudi Arabia. Data were collected using an online, validated, close-ended structured questionnaire distributed through social media. Linear regression analysis was used to assess independent predictors of knowledge regarding HZ, knowledge regarding the HZ vaccine, and attitudes toward HZ. Categorical variables were dummy-coded. Binary logistic regression was used to assess factors associated with the willingness to receive the HZ vaccine. Results A total of 368 respondents completed the questionnaire. The mean knowledge scores (%) regarding HZ and its vaccine were 28.6% and 37.1%, respectively. While 51.6% (n = 190) claimed to be aware of the HZ vaccine, only 31.6% (n = 60) had a knowledge score of 80% or higher. Multivariate analysis showed that knowledge was positively associated with female gender, prior chickenpox infection, and higher education. Only 54.4% of the respondents were willing to get the HZ vaccine, and 28.8% were willing to pay out of pocket for the HZ vaccine. Conclusion The results suggest that educational campaigns on HZ and its vaccine targeting at-risk groups are required to raise awareness and increase the public's knowledge. Additionally, healthcare personnel's recommendation of the HZ vaccine to the target population should be encouraged, as it is an important factor in vaccine acceptability.

Molecular engineering tools for the development of vaccines against infectious diseases: current status and future directions

INTRODUCTION

The escalating global changes have fostered conditions for the expansion and transmission of diverse biological factors, leading to the rise of emerging and reemerging infectious diseases. Complex viral infections, such as COVID-19, influenza, HIV, and Ebola, continue to surface, necessitating the development of effective vaccine technologies.

AREAS COVERED

This review article highlights recent advancements in molecular biology, virology, and genomics that have propelled the design and development of innovative molecular tools. These tools have promoted new vaccine research platforms and directly improved vaccine efficacy. The review summarizes the cutting-edge molecular engineering tools used in creating novel vaccines and explores the rapidly expanding molecular tools landscape and potential directions for future vaccine development.

EXPERT OPINION

The strategic application of advanced molecular engineering tools can address conventional vaccine limitations, enhance the overall efficacy of vaccine products, promote diversification in vaccine platforms, and form the foundation for future vaccine development. Prioritizing safety considerations of these novel molecular tools during vaccine development is crucial.

Challenges in the Vaccination of the Elderly and Strategies for Improvement

In recent years, the elderly has become a rapidly growing proportion of the world's population as life expectancy is extending. Immunosenescence and inflammaging contribute to the increased risk of chronic non-communicable and acute infectious diseases. Frailty is highly prevalent in the elderly and is associated with an impaired immune response, a higher propensity to infection, and a lower response to vaccines. Additionally, the presence of uncontrolled comorbid diseases in the elderly also contributes to sarcopenia and frailty. Vaccine-preventable diseases that threaten the elderly include influenza, pneumococcal infection, herpes zoster, and COVID-19, which contribute to significant disability-adjusted life years lost. Previous studies had shown that conventional vaccines only yielded suboptimal protection that wanes rapidly in a shorter time. This article reviews published papers on several vaccination strategies that were developed for the elderly to solve these problems: more immunogenic vaccine formulations using larger doses of antigen, stronger vaccine adjuvants, recombinant subunit or protein conjugated vaccines, newly developed mRNA vaccines, giving booster shots, and exploring alternative routes of administration. Included also are several publications on senolytic medications under investigation to boost the immune system and vaccine response in the elderly. With all those in regard, the currently recommended vaccines for the elderly are presented.

Preclinical developments in the delivery of protein antigens for vaccination

INTRODUCTION

Vaccine technology has constantly advanced since its origin. One of these advancements is where purified parts of a pathogen are used rather than the whole pathogen. Subunit vaccines have no chance of causing disease; however, alone these antigens are often poorly immunogenic. Therefore, they can be paired with immune stimulating adjuvants. Further, subunits can be combined with delivery strategies such as nano/microparticles to enrich their delivery to organs and cells of interest as well as protect them from in vivo degradation. Here, we seek to highlight some of the more promising delivery strategies for protein antigens.

AREAS COVERED

We present a brief description of the different types of vaccines, clinically relevant examples, and their disadvantages when compared to subunit vaccines. Also, specific preclinical examples of delivery strategies for protein antigens.

EXPERT OPINION

Subunit vaccines provide optimal safety given that they have no risk of causing disease; however, they are often not immunogenic enough on their own to provide protection. Advanced delivery systems are a promising avenue to increase the immunogenicity of subunit vaccines, but scalability and stability can be improved. Further, more research is warranted on systems that promote a mucosal immune response to provide better protection against infection.

Saponins: Research Progress and Their Potential Role in the Post-COVID-19 Pandemic Era

In the post-COVID-19 pandemic era, the new global situation and the limited therapeutic management of the disease make it necessary to take urgent measures in more effective therapies and drug development in order to counteract the negative global impacts caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its new infectious variants. In this context, plant-derived saponins-glycoside-type compounds constituted from a triterpene or steroidal aglycone and one or more sugar residues-may offer fewer side effects and promising beneficial pharmacological activities. This can then be used for the development of potential therapeutic agents against COVID-19, either as a therapy or as a complement to conventional pharmacological strategies for the treatment of the disease and its prevention. The main objective of this review was to examine the primary and current evidence in regard to the therapeutic potential of plant-derived saponins against the COVID-19 disease. Further, the aim was to also focus on those studies that highlight the potential use of saponins as a treatment against SARS-CoV-2. Saponins are antiviral agents that inhibit different pharmacological targets of the virus, as well as exhibit anti-inflammatory and antithrombotic activity in relieving symptoms and clinical complications related to the disease. In addition, saponins also possess immunostimulatory effects, which improve the efficacy and safety of vaccines for prolonging immunogenicity against SARS-CoV-2 and its infectious variants.

A Cross-Sectional Study of the Knowledge, Practice, and Attitude Towards Herpes Zoster Vaccination Among the General Population in the Western Region of Saudi Arabia

Introduction Herpes zoster (HZ) is a viral infection that occurs due to the reactivation of the varicella-zoster virus. The vaccination against herpes zoster to prevent its complications has been approved for individuals 50 years of age and older. This study aims to evaluate the knowledge, attitudes, and habits of at-risk populations about the varicella-zoster virus and its vaccination. Methodology A quantitative, observational, cross-sectional study was conducted among 500 adults over 50 years of age. Participants were selected by non-probability, convenience sampling from public places. RStudio (R version 4.1.1) was used to analyze the data. Result Eighty-three percent (n = 416) of participants had heard of herpes zoster (HZ). Seventy-four percent of respondents (n = 368) did not recognize the link between varicella and herpes zoster. Multiple linear regression showed that individuals who had varicella and heard about herpes zoster were the only positive predictors of herpes zoster knowledge. Out of all the respondents, 55.8% (n = 279) had heard of the herpes zoster vaccine, but 94.6% (n = 473) had not taken it. Among the respondents, 28.1% (n = 118) were unwilling to take optional vaccines; 77.4% (n = 387) agreed to take the HZ vaccine if recommended by a healthcare professional. Conclusion The general Saudi population had a good understanding of HZ and its vaccine. Their attitudes toward the HZ vaccine were generally positive; however, poor practices were observed. We recommend that arranging national campaigns targeting at-risk populations can enhance awareness about herpes zoster and its vaccine, subsequently increasing the rate of HZ immunization.

Reactivation of Herpes Zoster After Recombinant Vaccine (Shingrix): A Case Report

Herpes zoster (HZ) is a common contagious dermatological condition that results from reactivation of varicella-zoster virus (VZV), which currently could be prevented by vaccination. We describe a rare case of varicella infection reactivation after routine zoster vaccination in an immunocompetent female in her 60s who developed dermatomal pruritic and vesicular rash one week after receiving Shingrix vaccine, along with fever, sweating, headache, and fatigue. The patient was treated as a case of herpes zoster reactivation with a seven days course of acyclovir. She continued to do well on follow-up with no significant complications. Though uncommon, it is important for healthcare providers to recognize this adverse reaction to expedite testing and treatment.

An Atypical Rash in Disseminated Herpes Zoster: A Case Report

Disseminated cutaneous herpes zoster (DCHZ) is an atypical presentation of herpes zoster (HZ) that mainly affects immunosuppressed patients. Given the potential risk for visceral fatal involvement, prompt recognition of this condition is crucial. In this case report, we present the case of a 90-year-old male with chronic lymphocytic leukemia under chlorambucil treatment who presented to the emergency department with multiple, converging, crusted papules on his face. He was misdiagnosed with a drug eruption and hospitalized after switching the antibiotic therapy. After one week, the lesions spread in a cephalocaudal pattern, affecting both the trunk and limbs, following which the Dermatology team was consulted. We performed an HZV smear test and initiated acyclovir. Unfortunately, the test was positive, and DCHZ was confirmed. The patient died one week later due to pneumonitis which evolved into a severe acute respiratory distress syndrome.

Potentiating pneumococcal glycoconjugate vaccine PCV13 with saponin adjuvant VSA-1

VSA-1 is a semisynthetic saponin adjuvant prepared from naturally occurring Momordica saponin and capable of stimulating antigen-specific humoral and cellular immune responses. Its immunostimulating activity in enhancing the immune responses induced by the clinical glycoconjugate pneumococcal vaccine PCV13 is compared with QS-21 in female BALB/c mice. Both VSA-1 and QS-21 boosted IgG and opsonic antibodies titers against seven selected serotypes, including serotypes 3, 14, and 19A that are involved in most PCV13 breakthroughs. Since VSA-1 is much more accessible and of lower toxicity than QS-21, it can be a practical saponin immunostimulant to be included in a new glycoconjugate pneumococcal vaccine formulation.

Structure-Activity Relationship Study of Momordica Saponin II Derivatives as Vaccine Adjuvants

VSA-2 is a recently developed semisynthetic saponin immunostimulant. It is prepared by incorporating a terminal-functionalized side chain to the branched trisaccharide domain at the C3 position of Momordica saponin II (MS II) isolated from the seeds of perennial Momordica cochinchinensis Spreng. Direct comparison of VSA-2 and the clinically proven saponin adjuvant QS-21 shows that VSA-2 is comparable to QS-21 in enhancing humoral and cellular immune responses. Structure-activity relationship studies show that structural changes in the side chain have a significant impact on saponins' adjuvant activity. However, with the VSA-2 molecular framework intact, the new VSA-2 analogues with various substitution(s) at the terminal benzyl group of the side chain retain the ability of potentiating antigen-specific humoral and cellular responses.

Recombinant vaccines in 2022: a perspective from the cell factory

The last big outbreaks of Ebola fever in Africa, the thousands of avian influenza outbreaks across Europe, Asia, North America and Africa, the emergence of monkeypox virus in Europe and specially the COVID-19 pandemics have globally stressed the need for efficient, cost-effective vaccines against infectious diseases. Ideally, they should be based on transversal technologies of wide applicability. In this context, and pushed by the above-mentioned epidemiological needs, new and highly sophisticated DNA-or RNA-based vaccination strategies have been recently developed and applied at large-scale. Being very promising and effective, they still need to be assessed regarding the level of conferred long-term protection. Despite these fast-developing approaches, subunit vaccines, based on recombinant proteins obtained by conventional genetic engineering, still show a wide spectrum of interesting potentialities and an important margin for further development. In the 80's, the first vaccination attempts with recombinant vaccines consisted in single structural proteins from viral pathogens, administered as soluble plain versions. In contrast, more complex formulations of recombinant antigens with particular geometries are progressively generated and explored in an attempt to mimic the multifaceted set of stimuli offered to the immune system by replicating pathogens. The diversity of recombinant antimicrobial vaccines and vaccine prototypes is revised here considering the cell factory types, through relevant examples of prototypes under development as well as already approved products.

Varicella zoster virus and cardiovascular diseases

Varicella zoster virus (VZV) is a Herpesviridae family double-stranded DNA virus that only affects humans. The first clinical manifestation appears to be varicella, typical of childhood. VZV, on the other hand, becomes latent in ganglion neurons throughout the neuroaxis after primary infection. The VZV reactivates and travels along peripheral nerve fibers in the elderly and immunocompromised individuals, resulting in Zoster. It can, however, spread centrally and infect cerebral and extracranial arteries, resulting in vasculopathy, which can lead to transient ischemic attacks, strokes, aneurysms, cavernous sinus thrombosis, giant cell arteritis, and granulomatous aortitis. Although the mechanisms of virus-induced pathological vascular remodeling are not fully understood, recent research indicates that inflammation and dysregulation of ligand-1 programmed death play a significant role. Few studies, on the other hand, have looked into the role of VZV in cardiovascular disease. As a result, the purpose of this review is to examine the relationship between VZV and cardiovascular disease, the efficacy of the vaccine as a protective mechanism, and the target population of heart disease patients who could benefit from vaccination.

Vaccination strategies for Korean patients with inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) are vulnerable to vaccine-preventable infectious diseases. Immunosuppressive drugs, which are often used to manage IBD, may increase this vulnerability and attenuate vaccine efficacy. Thus, healthcare providers should understand infectious diseases and schedule vaccinations for them to reduce the infection-related burden of patients with IBD. All patients with IBD should be assessed in terms of immunity to vaccine-preventable diseases at the time of IBD diagnosis, and be vaccinated appropriately. Vaccination is becoming more important because of the unprecedented coronavirus disease 2019 (COVID-19) global health crisis. This review focuses on recent updates to vaccination strategies for Korean patients with IBD.

Impact of hemagglutination activity and M2e immunity on conferring protection against influenza viruses

To improve cross-protection of influenza vaccination, we tested conjugation of conserved M2e epitopes to the surface of inactivated influenza virus (iPR8-M2e*). Treatment of virus with chemical cross-linker led to diminished hemagglutination activity and failure to induce hemagglutination inhibiting antibodies. Conjugated iPR8-M2e* vaccine was less protective against homologous and heterosubtypic viruses, despite the induction of virus-specific binding IgG antibodies. In alternative approaches to enhance cross-protection, we developed a genetically linked chimeric protein (M2e-B stalk) vaccine with M2e of influenza A and hemagglutinin (HA) stalk of influenza B virus. Vaccination of mice with inactivated influenza A virus supplemented with M2e-B stalk effectively induced hemagglutination inhibiting antibodies, humoral and cellular M2e immune responses, and enhanced heterosubtypic protection. This study demonstrates the importance of HA functional integrity in influenza vaccine efficacy and that supplementation of influenza vaccines with M2e-B stalk protein could be a feasible strategy of improving cross-protection against influenza viruses.

Baculovirus Display of Varicella-Zoster Virus Glycoprotein E Induces Robust Humoral and Cellular Immune Responses in Mice

Varicella-zoster virus (VZV) is the causative agent of varicella and herpes zoster (HZ) and can pose a significant challenge to human health globally. The initial VZV infection-more common in children-causes a self-limiting chicken pox. However, in later life, the latent VZV can become reactivated in these patients, causing HZ and postherpetic neuralgia (PHN), a serious and painful complication. VZV glycoprotein E (gE) has been developed into a licensed subunit vaccine against HZ (Shingrix). However, its efficacy relies on the concomitant delivery of a robust adjuvant (AS01B). Here, we sought to create a new immunogen for vaccine design by displaying the VZV-gE on the baculovirus surface (Bac-gE). Correct localization and display of gE on the engineered baculovirus was verified by flow cytometry and immune electron microscopy. We show that Bac-gE provides excellent antigenicity against VZV and induces not only stronger gE-specific CD4+ and CD8+ T cell responses but also higher levels of VZV-specific neutralizing antibodies as compared with other vaccine strategies in mice. Collectively, we show that the baculovirus display of VZV-gE confers ideal humoral and cellular immune responses required for HZ vaccine development, paving the way for a baculovirus-based vaccine design.

Intramuscular Inoculation of AS02-Adjuvanted Respiratory Syncytial Virus (RSV) F Subunit Vaccine Shows Better Efficiency and Safety Than Subcutaneous Inoculation in BALB/c Mice

We previously explored a panel of adjuvants formulated with pre-fusion RSV-F protein and found that AS02 may be a promising candidate adjuvant for developing RSV-F subunit vaccines with improved immunogenicity and desired immune response type. In this study, we performed a head-to-head comparison of the effect of intramuscular injection to that of subcutaneous injection on the immune response and protective efficacy of recombinant RSV-F subunit vaccine with or without adjuvants (Alhydrogel, squalene-based emulsion adjuvants MF59, AS03, and AS02) in BALB/c mice. After inoculations, antigen-specific antibodies, neutralizing antibodies, antibody subtypes, cytokines, and the persistence of immune response were evaluated. Moreover, challenge tests were also performed to illustrate the possible effect of inoculation routes and adjuvant on virus clearance and histochemistry changes in the lungs of mice. The results indicated that intramuscular inoculation is a more effective and antigen dose-sparing route to enhance the immune response, although subcutaneous inoculation induced faster and stronger IgG antibodies after the initial immunization. Furthermore, adjuvant, but not immunization route, is a more critical factor to affect the humoral/cellular immune response and the immune bias. In addition, adjuvant inoculated via the intramuscular route is safer than that via the subcutaneous route, especially for AS02. This study highlights the importance of the adjuvant and immunization routes in the design and clinical transformation of adjuvanted vaccines. Further investigation is needed to illustrate the mechanism underlying the above difference in both efficiency and safety.

A chimeric thermostable M2e and H3 stalk-based universal influenza A virus vaccine

We developed a new chimeric M2e and H3 hemagglutinin (HA) stalk protein vaccine (M2e-H3 stalk) by genetic engineering of modified H3 stalk domain conjugated with conserved M2e epitopes to overcome the drawbacks of low efficacy by monomeric domain-based universal vaccines. M2e-H3 stalk protein expressed and purified from Escherichia coli was thermostable, displaying native-like antigenic epitopes recognized by antisera of different HA subtype proteins and influenza A virus infections. Adjuvanted M2e-H3 stalk vaccination induced M2e and stalk-specific IgG antibodies recognizing viral antigens on virus particles and on the infected cell surface, CD4⁺ and CD8⁺ T-cell responses, and antibody-dependent cytotoxic cell surrogate activity in mice. M2e-H3 stalk was found to confer protection against heterologous and heterosubtypic cross-group subtype viruses (H1N1, H5N1, H9N2, H3N2, H7N9) at similar levels in adult and aged mice. These results provide evidence that M2e-H3 stalk chimeric proteins can be developed as a universal influenza A virus vaccine candidate for young and aged populations.

Immunological characteristics of MAV/06 strain of varicella-zoster virus vaccine in an animal model

BACKGROUND

Varicella-zoster virus (VZV) is a pathogen that causes chickenpox and shingles in humans. Different types of the varicella vaccines derived from the Oka and MAV/06 strains are commercially available worldwide. Although the MAV/06 vaccine was introduced in 1990s, little was known about immunological characteristics.

RESULTS

Here, we evaluated B and T cell immune response in animals inoculated with the Oka and MAV/06 vaccines as well as a new formulation of the MAV/06 vaccine. A variety of test methods were applied to evaluate T and B cell immune response. Plaque reduction neutralization test (PRNT) and fluorescent antibody to membrane antigen (FAMA) assay were conducted to measure the MAV/06 vaccine-induced antibody activity against various VZVs. Glycoprotein enzyme-linked immunosorbent assay (gpELISA) was used to compare the degree of the antibody responses induced by the two available commercial VZV vaccines and the MAV/06 vaccine. Interferon-gamma enzyme-linked immunosorbent spot (IFN-γ ELISpot) assays and cytokine bead array (CBA) assays were conducted to investigate T cell immune responses. Antibodies induced by MAV/06 vaccination showed immunogenicity against a variety of varicella-zoster virus and cross-reactivity among the virus clades.

CONCLUSIONS

It is indicating the similarity of the antibody responses induced by commercial varicella vaccines and the MAV/06 vaccine. Moreover, VZV-specific T cell immune response from MAV/06 vaccination was increased via Th1 cell response. MAV/06 varicella vaccine induced both humoral and cellular immune response via Th1 cell mediated response.

Thermostable H1 hemagglutinin stem with M2e epitopes provides broad cross-protection against group1 and 2 influenza A viruses

Hemagglutinin (HA) stem-based vaccines have limitations in providing broad and effective protection against cross-group influenza viruses, despite being a promising universal vaccine target. To overcome the limited cross-protection and low efficacy by HA stem vaccination, we genetically engineered a chimeric conjugate of thermostable H1 HA stem and highly conserved M2e repeat (M2e-H1stem), which was expressed at high yields in Escherichia coli. M2e-H1stem protein presented native-like epitopes reactive to antisera of live virus infection. M2e-H1stem protein vaccination of mice induced strong M2e- and HA stem-specific immune responses, conferring broadly effective cross-protection against both antigenically distinct group 1 (H1N1, H5N1, and H9N2 subtypes) and group 2 (H3N2 and H7N9 subtypes) seasonal and pandemic potential influenza viruses. M2e-H1stem vaccination generated CD4⁺ and CD8⁺ T cell responses and antibody-dependent cytotoxic cellular and humoral immunity, which contributed to enhancing cross-protection. Furthermore, comparable broad cross-group protection was observed in older aged mice after M2e-H1stem vaccination. This study provides evidence warranting further development of chimeric M2e-stem proteins as a promising universal influenza vaccine candidate in adult and aged populations.

A New Nano Adjuvant of PF3 Used for an Enhanced Hepatitis B Vaccine

Recombinant protein vaccines, with highly pure ingredients and good safety, are gradually replacing some attenuated and inactivated vaccines in clinical practice. However, since their low immunogenicity of the recombinant proteins, adjuvants are often needed to enhance immune response after vaccination. Aluminum adjuvant has been widely used in some vaccines for decades, it can induce strong humoral immunity, but the deficiency of cellular immunity limits its application for some vaccines. Therefore, it is urgently needed to develop novel adjuvant to increase not only humoral but also cellular immune response. To address this, we designed and prepared a new nano adjuvant (PF3) through microfluidization by the combination of saponin (Ginsenoside Rg1) and oil-in-water nano emulsion (NE) in the present study. As compared to aluminum adjuvant, PF3 had stronger humoral and cellular immune induction effect because of high cellular uptake and activization of immune response pathways. Furthermore, PF3 showed better immune enhancement and acceptable biosafety equivalent to that of aluminum adjuvant. In addition, no obvious changes of PF3 were observed in size and zeta potential after 12 weeks storage at 4 and 37°C, demonstrating its high stability in vitro. This study provided an adjuvant platform to replace traditional aluminum adjuvant in design of recombinant vaccines.

Knowledge, attitudes, and practices of the United Arab Emirates population towards Herpes Zoster vaccination: A cross-sectional study

Herpes Zoster is a viral infection that occurs due to reactivation of the Varicella Zoster virus. A vaccine has been approved for adults aged 50 and above for the prevention of Herpes Zoster and its complications. This study aims to assess the at-risk population’s awareness of the disease and its vaccine, and attitudes and practices toward the vaccine. A quantitative, observational, cross-sectional study was conducted among 420 adults above the age of 50. Non-probability, convenience sampling was used to select participants from public venues. SPSS-25 was used to analyze the data. 64.3% (n = 270) of participants heard of Herpes Zoster. 78.3% (n = 329) did not recognize the link between chickenpox and Herpes Zoster. Multiple linear regression showed that being female, Arab expatriate, or healthcare professional were the only positive predictors of Herpes Zoster knowledge. 14.8% (n = 62) heard of Herpes Zoster vaccine but 96.7% (n = 406) had not taken it. Participants with chronic diseases were 2.064 times more likely to hear about the vaccine than healthy participants (p = 0.026). Multiple linear regression showed that being a healthcare professional was the only significant predictor of Herpes Zoster vaccine knowledge. 28.1% (n = 118) were not willing to take optional vaccines. Those reluctant to take optional vaccines were 26.023 times more likely to take them if recommended by a healthcare professional (p < 0.001). Attitudes toward Herpes Zoster vaccine were generally positive; however, due to lack of knowledge, poor practices were observed. Nationwide campaigns aimed toward at-risk groups can raise awareness on Herpes Zoster and its vaccine, subsequently improving Herpes Zoster vaccination rate.

COVID-19 Vaccines: Current and Future Perspectives

Currently available vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are highly effective but not able to keep the coronavirus disease 2019 (COVID-19) pandemic completely under control. Alternative R&D strategies are required to induce a long-lasting immunological response and to reduce adverse events as well as to favor rapid development and large-scale production. Several technological platforms have been used to develop COVID-19 vaccines, including inactivated viruses, recombinant proteins, DNA- and RNA-based vaccines, virus-vectored vaccines, and virus-like particles. In general, mRNA vaccines, protein-based vaccines, and vectored vaccines have shown a high level of protection against COVID-19. However, the mutation-prone nature of the spike (S) protein affects long-lasting vaccine protection and its effectiveness, and vaccinated people can become infected with new variants, also showing high virus levels. In addition, adverse effects may occur, some of them related to the interaction of the S protein with the angiotensin-converting enzyme 2 (ACE-2). Thus, there are some concerns that need to be addressed and challenges regarding logistic problems, such as strict storage at low temperatures for some vaccines. In this review, we discuss the limits of vaccines developed against COVID-19 and possible innovative approaches.

Enhanced Potency and Persistence of Immunity to Varicella-Zoster Virus Glycoprotein E in Mice by Addition of a Novel BC02 Compound Adjuvant

Herpes zoster (HZ) is one of two distinct syndromes caused by Varicella-zoster virus (VZV). A primary infection with VZV causes varicella in susceptible young children. After resolution of the primary infection, VZV establishes a lifelong latency within the cranial or dorsal root ganglia. With increasing age, family history of shingles, immunosuppression or other risk factors, there is a decline in the virus-specific T-cell-mediated immune (CMI) response which allows reactivation of latent VZV in the root ganglia resulting in HZ. There are currently two vaccines that have been approved to prevent HZ and postherpetic neuralgia (PHN) but one is a live attenuated vaccine, the protective effect of which is considered to decrease significantly with the age of the recipient. However, a recombinant subunit vaccine may provide targeted VZV-specific cellular and humoral immunity, giving it a more potent and longer-lasting protective effect against HZ. The current study reports the development of a novel adjuvant, BC02 (BCG CpG DNA compound adjuvants system 02), composed of Al(OH)₃ inorganic salt adjuvant and BC01 (BCG CpG DNA compound adjuvants system 01), a Toll-like receptor 9 (TLR9) agonist. Immunogenicity and compatibility with recombinant VZV glycoprotein E (gE) in mice were studied. The BC02-adjuvanted gE experimental vaccine was highly effective in eliciting both humoral and cellular immune responses to the recombinant gE glycoprotein and VZV-Oka in a mouse model. The efficient production and long-term persistence of gE and VZV-Oka-specific IFN-γ, IL-2-specific T cells and memory B cells in the early (1W), middle (7W), middle-late (15W), and final (27W) immune stages were established. Results of fluorescent antibody to membrane antigen (FAMA) and serum antibody plaque reduction tests also showed that the BC02 adjuvanted-gE experimental vaccine induced mice to secrete neutralizing antibodies against clinically isolated VZV strains. In combination, the current data suggest that the BC02 compound adjuvant offers a strategy to induce an appropriately strong cellular and humoral immunity against the VZV gE protein subunit to improve vaccine efficacy.

SARS-CoV-2 receptor binding domain displayed on HBsAg virus-like particles elicits protective immunity in macaques

Authorized vaccines against SARS-CoV-2 remain less available in low- and middle-income countries due to insufficient supply, high costs, and storage requirements. Global immunity could still benefit from new vaccines using widely available, safe adjuvants, such as alum and protein subunits, suited to low-cost production in existing manufacturing facilities. Here, a clinical-stage vaccine candidate comprising a SARS-CoV-2 receptor binding domain-hepatitis B surface antigen virus-like particle elicited protective immunity in cynomolgus macaques. Titers of neutralizing antibodies (>104) induced by this candidate were above the range of protection for other licensed vaccines in nonhuman primates. Including CpG 1018 did not significantly improve the immunological responses. Vaccinated animals challenged with SARS-CoV-2 showed reduced median viral loads in bronchoalveolar lavage (~3.4 log10) and nasal mucosa (~2.9 log10) versus sham controls. These data support the potential benefit of this design for a low-cost modular vaccine platform for SARS-CoV-2 and other variants of concern or betacoronaviruses.

Leveraging self-assembled nanobiomaterials for improved cancer immunotherapy

Nanomaterials and targeted drug delivery vehicles improve the therapeutic index of drugs and permit greater control over their pharmacokinetics, biodistribution, and bioavailability. Here, nanotechnologies applied to cancer immunotherapy are discussed with a focus on current and next generation self-assembling drug delivery systems composed of lipids and/or polymers. Topics covered include the fundamental design, suitability, and inherent properties of nanomaterials that induce anti-tumor immune responses and support anti-cancer vaccination. Established active and passive targeting strategies as well as newer "indirect" methods are presented together with insights into how nanocarrier structure and surface chemistry can be leveraged for controlled delivery to the tumor microenvironment while minimizing off-target effects.

Liposomes as Adjuvants and Vaccine Delivery Systems

The review considers liposomes as systems of substantial interest as adjuvant carriers in vaccinology due to their versatility and maximal biocompatibility. Research and development on the use of liposomes and lipid nanoparticles to create subunit vaccines for the prevention and treatment of infectious diseases has been going on for several decades. In recent years, the area has seen serious progress due to the improvement of the technology of industrial production of various high-grade lipids suitable for parenteral administration and the emergence of new technologies and equipment for the production of liposomal preparations. When developing vaccines, it is necessary to take into account how the body’s immune system (innate and adaptive immunity) functions. The review briefly describes some of the fundamental mechanisms underlying the mobilization of immunity when encountering an antigen, as well as the influence of liposome carriers on the processes of internalization of antigens by immunocompetent cells and ways of immune response induction. The results of the studies on the interactions of liposomes with antigen-presenting cells in function of the liposome size, charge, and phase state of the bilayer, which depends on the lipid composition, are often contradictory and should be verified in each specific case. The introduction of immunostimulant components into the composition of liposomal vaccine complexes—ligands of the pathogen-associated molecular pattern receptors—permits modulation of the strength and type of the immune response. The review briefly discusses liposome-based vaccines approved for use in the clinic for the treatment and prevention of infectious diseases, including mRNA-loaded lipid nanoparticles. Examples of liposomal vaccines that undergo various stages of clinical trials are presented.

Innate Immune Memory and the Host Response to Infection

Unlike the adaptive immune system, the innate immune system has classically been characterized as being devoid of memory functions. However, recent research shows that innate myeloid and lymphoid cells have the ability to retain memory of prior pathogen exposure and become primed to elicit a robust, broad-spectrum response to subsequent infection. This phenomenon has been termed innate immune memory or trained immunity. Innate immune memory is induced via activation of pattern recognition receptors and the actions of cytokines on hematopoietic progenitors and stem cells in bone marrow and innate leukocytes in the periphery. The trained phenotype is induced and sustained via epigenetic modifications that reprogram transcriptional patterns and metabolism. These modifications augment antimicrobial functions, such as leukocyte expansion, chemotaxis, phagocytosis, and microbial killing, to facilitate an augmented host response to infection. Alternatively, innate immune memory may contribute to the pathogenesis of chronic diseases, such as atherosclerosis and Alzheimer's disease.

Presentation, Management, and Prevention of Herpes Zoster

The purpose of the Research to Practice column is to review and critique current research articles that directly affect the advanced practice nurse's (APN's) practice in the emergency department. This review examines the findings of Schmidt and Rowbotham's (2017) article, "Aggressive Noninvasive Treatment of Acute Herpes Zoster for the Prevention of Postherpetic Neuralgia. Herpes Zoster: Postherpetic Neuralgia and Other Complications." The authors completed an extensive literature review and created 6 key clinical recommendations for treating acute herpes zoster to prevent postherpetic neuralgia, including prevention, patient education and counseling, proper diagnosing, medication selection, and treatment specific to acute herpes zoster postherpetic neuralgia. This review provides a strategy to allow APNs to confidently recognize and treat acute herpes zoster and postherpetic neuralgia to reduce patient risks and avoid mistreatment of acute herpes zoster and postherpetic pain.

Future Directions for the Discovery of Natural Product-Derived Immunomodulating Drugs

Drug discovery from natural sources is going through a renaissance, having spent many decades in the shadow of synthetic molecule drug discovery, despite the fact that natural product-derived compounds occupy a much greater chemical space than those created through synthetic chemistry methods. With this new era comes new possibilities, not least the novel targets that have emerged in recent times and the development of state-of-the-art technologies that can be applied to drug discovery from natural sources. Although progress has been made with some immunomodulating drugs, there remains a pressing need for new agents that can be used to treat the wide variety of conditions that arise from disruption, or over-activation, of the immune system; natural products may therefore be key in filling this gap. Recognising that, at present, there is no authoritative article that details the current state-of-the-art of the immunomodulatory activity of natural products, this in-depth review has arisen from a joint effort between the International Union of Basic and Clinical Pharmacology (IUPHAR) Natural Products and Immunopharmacology, with contributions from a Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation number of world-leading researchers in the field of natural product drug discovery, to provide a "position statement" on what natural products has to offer in the search for new immunomodulatory argents. To this end, we provide a historical look at previous discoveries of naturally occurring immunomodulators, present a picture of the current status of the field and provide insight into the future opportunities and challenges for the discovery of new drugs to treat immune-related diseases.

Comparison of the effects of different potent adjuvants on enhancing the immunogenicity and cross-protection by influenza virus vaccination in young and aged mice

Vaccination against influenza viruses suffers from low efficacy in conferring homologous and cross-protection, particularly in older adults. Here, we compared the effects of three different adjuvant types (QS-21+MPL, CpG+MPL and bacterial cell wall CWS) on enhancing the immunogenicity and homologous and heterosubtypic protection of influenza vaccination in young adult and aged mouse models. A combination of saponin QS-21 and monophosphoryl lipid A (QS-21+MPL) was most effective in inducing T helper type 1 (Th1) T cell and cross-reactive IgG as well as hemagglutination inhibiting antibody responses to influenza vaccination. Both combination adjuvants (QS-21+MPL and CpG+MPL) exhibited high potency by preventing weight loss and reducing viral loads and enhanced homologous and cross-protection by influenza vaccination in adult and aged mouse models. Bacillus Calmette-Guerin cell-wall skeleton (CWS) displayed substantial adjuvant effects on immune responses to influenza vaccination but lower adjuvant efficacy in inducing Th1 IgG responses, cross-protection in adult mice, and in conferring homologous protection in aged mice. This study has significance in comparing the effects of potent adjuvants on enhancing humoral and cellular immune responses to influenza virus vaccination, inducing homologous and cross-protection in adult and aged populations.

Organizing Pneumonia Following Recombinant Zoster Vaccination: A Rare Adverse Reaction

We describe a case of a severe but rare adverse reaction to recombinant varicella-zoster virus (VZV) vaccination: a 67-year-old female admitted with gradual onset of shortness of breath, hypoxia, and fever following VZV vaccination. The clinical picture and radiologic presentation mimicked COVID-19 pneumonia. However, repeated testing for COVID-19 by PCR was negative. A diagnosis of organizing pneumonia was made on transbronchial biopsies. The patient responded well to steroids and improved both clinically and radiographically. This case illustrates not only a rare and unreported complication from vaccination but also raises the awareness during the COVID-19 pandemic that other etiologies can mimic COVID-19 pneumonia. Physicians should be aware of other diagnoses that can mimic COVID-19 infection.

Soapbark Triterpenes: Quillaja brasiliensis Cell Culture Sapogenin and Free Sterol Analysis by GCMS

Triterpene saponins of the genus Quillaja (Quillajaceae) are known for their immunoadjuvant, hypocholesterolemic, and anti-inflammatory activity. Plant cell cultures are useful for the study of saponin metabolism and industrial production of these bioactive compounds. While structurally related phytosterols are primary metabolites essential to growth and development, saponins are responsive to pathogen and abiotic stress, fulfilling roles in plant specialized metabolism. For cell culture production of saponins, phytosterols may be considered a competing pathway which relies on a common pool of cytosolic isoprenoid precursors.Understanding the metabolic allocation of resources between these two related pathways is key to maximizing saponin production in in vitro production systems. Sterols and saponins naturally occur in multiple conjugated forms, which complicate separation and quantification. The acid hydrolysis of conjugated sterols and saponins to their free forms is a useful technique to simplify their analysis by gas chromatography. Here we provide the workflow for the quantification of free sterols and sapogenins in cell cultures of Quillaja brasiliensis .

Nanovaccine Delivery Approaches and Advanced Delivery Systems for the Prevention of Viral Infections: From Development to Clinical Application

Viral infections causing pandemics and chronic diseases are the main culprits implicated in devastating global clinical and socioeconomic impacts, as clearly manifested during the current COVID-19 pandemic. Immunoprophylaxis via mass immunisation with vaccines has been shown to be an efficient strategy to control such viral infections, with the successful and recently accelerated development of different types of vaccines, thanks to the advanced biotechnological techniques involved in the upstream and downstream processing of these products. However, there is still much work to be done for the improvement of efficacy and safety when it comes to the choice of delivery systems, formulations, dosage form and route of administration, which are not only crucial for immunisation effectiveness, but also for vaccine stability, dose frequency, patient convenience and logistics for mass immunisation. In this review, we discuss the main vaccine delivery systems and associated challenges, as well as the recent success in developing nanomaterials-based and advanced delivery systems to tackle these challenges. Manufacturing and regulatory requirements for the development of these systems for successful clinical and marketing authorisation were also considered. Here, we comprehensively review nanovaccines from development to clinical application, which will be relevant to vaccine developers, regulators, and clinicians.

Epigallocatechin-3-Gallate as a Novel Vaccine Adjuvant

Vaccine adjuvants from natural resources have been utilized for enhancing vaccine efficacy against infectious diseases. This study examined the potential use of catechins, polyphenolic materials derived from green tea, as adjuvants for subunit and inactivated vaccines. Previously, catechins have been documented to have irreversible virucidal function, with the possible applicability in the inactivated viral vaccine platform. In a mouse model, the coadministration of epigallocatechin-3-gallate (EGCG) with influenza hemagglutinin (HA) antigens induced high levels of neutralizing antibodies, comparable to that induced by alum, providing complete protection against the lethal challenge. Adjuvant effects were observed for all types of HA antigens, including recombinant full-length HA and HA1 globular domain, and egg-derived inactivated split influenza vaccines. The combination of alum and EGCG further increased neutralizing (NT) antibody titers with the corresponding hemagglutination inhibition (HI) titers, demonstrating a dose-sparing effect. Remarkably, EGCG induced immunoglobulin isotype switching from IgG1 to IgG2a (approximately >64-700 fold increase), exerting a more balanced TH1/TH2 response compared to alum. The upregulation of IgG2a correlated with significant enhancement of antibody-dependent cellular cytotoxicity (ADCC) function (approximately 14 fold increase), providing a potent effector-mediated protection in addition to NT and HI. As the first report on a novel class of vaccine adjuvants with built-in virucidal activities, the results of this study will help improve the efficacy and safety of vaccines for pandemic preparedness.

The characteristics of COVID-19 vaccine-related headache: Clues gathered from the healthcare personnel in the pandemic

Introduction

Headache is a frequent adverse event after viral vaccines. We aimed to investigate the frequency and clinical associations of COVID-19 vaccine-related headache.

Methods

The characteristics, associations of this headache, main comorbidities, headache history following the influenza vaccine and during COVID-19 were investigated using a web-based questionnaire.

Results

A total of 1819 healthcare personnel (mean age: 44.4 ± 13.4 years, 1222 females), vaccinated with inactivated virus, contributed to the survey; 209 (11.4%) had been infected with COVID-19. A total of 556 participants (30.6%) reported headache with significant female dominance (36.1% vs. 19.3%), 1.8 ± 3.5 (median: 1; IQR: 0–2) days following vaccination. One hundred and forty-four participants (25.9%) experienced headache lasting ≥3 days. Headache was mostly bilateral without accompanying phenomena, less severe, and shorter than COVID-19-related headache. The presence of primary headaches and migraine were significantly associated with COVID-19 vaccine-related headache (ORs = 2.16 [95% CI 1.74–2.68] and 1.65 [1.24–2.19], respectively). Headache during COVID-19 or following influenza vaccine also showed significant association with headache following COVID-19 vaccine (OR = 4.3 [95% CI 1.82–10.2] and OR = 4.84 [95% CI 2.84–8.23], respectively). Only thyroid diseases showed a significant association (OR = 1.54 [95% CI 1.15–2.08]) with vaccine-related headache among the common comorbidities.

Conclusion

Headache is observed in 30.6% of the healthcare workers following COVID-19 vaccine and mostly experienced by females with pre-existing primary headaches, thyroid disorders, headache during COVID-19, or headache related to the influenza vaccine.

Bullous fixed drug eruption following administration of the recombinant adjuvant Shingrix vaccine

A 51-year-old woman with Crohn’s disease presented with a bullous rash on her left arm and axilla 2 days after receiving her second dose of the recombinant adjuvant Shingrix vaccine. PCR for herpes simplex virus (HSV) 1, HSV 2 and varicella zoster virus was negative. Punch biopsy revealed changes that were consistent with a bullous fixed drug eruption. She was successfully treated oral prednisone and topical triamcinolone cream. This is the first known case of a bullous fixed drug eruption due to the recombinant adjuvant Shingrix vaccine.

Platforms for Production of Protein-Based Vaccines: From Classical to Next-Generation Strategies

To date, vaccination has become one of the most effective strategies to control and reduce infectious diseases, preventing millions of deaths worldwide. The earliest vaccines were developed as live-attenuated or inactivated pathogens, and, although they still represent the most extended human vaccine types, they also face some issues, such as the potential to revert to a pathogenic form of live-attenuated formulations or the weaker immune response associated with inactivated vaccines. Advances in genetic engineering have enabled improvements in vaccine design and strategies, such as recombinant subunit vaccines, have emerged, expanding the number of diseases that can be prevented. Moreover, antigen display systems such as VLPs or those designed by nanotechnology have improved the efficacy of subunit vaccines. Platforms for the production of recombinant vaccines have also evolved from the first hosts, Escherichia coli and Saccharomyces cerevisiae, to insect or mammalian cells. Traditional bacterial and yeast systems have been improved by engineering and new systems based on plants or insect larvae have emerged as alternative, low-cost platforms. Vaccine development is still time-consuming and costly, and alternative systems that can offer cost-effective and faster processes are demanding to address infectious diseases that still do not have a treatment and to face possible future pandemics.

A modular protein subunit vaccine candidate produced in yeast confers protection against SARS-CoV-2 in non-human primates

Vaccines against SARS-CoV-2 have been distributed at massive scale in developed countries, and have been effective at preventing COVID-19. Access to vaccines is limited, however, in low- and middle-income countries (LMICs) due to insufficient supply, high costs, and cold storage requirements. New vaccines that can be produced in existing manufacturing facilities in LMICs, can be manufactured at low cost, and use widely available, proven, safe adjuvants like alum, would improve global immunity against SARS-CoV-2. One such protein subunit vaccine is produced by the Serum Institute of India Pvt. Ltd. and is currently in clinical testing. Two protein components, the SARS-CoV-2 receptor binding domain (RBD) and hepatitis B surface antigen virus-like particles (VLPs), are each produced in yeast, which would enable a low-cost, high-volume manufacturing process. Here, we describe the design and preclinical testing of the RBD-VLP vaccine in cynomolgus macaques. We observed titers of neutralizing antibodies (>104) above the range of protection for other licensed vaccines in non-human primates. Interestingly, addition of a second adjuvant (CpG1018) appeared to improve the cellular response while reducing the humoral response. We challenged animals with SARS-CoV-2, and observed a ~3.4 and ~2.9 log10 reduction in median viral loads in bronchoalveolar lavage and nasal mucosa, respectively, compared to sham controls. These results inform the design and formulation of current clinical COVID-19 vaccine candidates like the one described here, and future designs of RBD-based vaccines against variants of SARS-CoV-2 or other betacoronaviruses.

Just add water: hydratable, morphologically diverse nanocarrier powders for targeted delivery

Two major obstacles that limit the widespread usage of polymeric nanocarriers include the complexity of formulation methods and their stability during storage. To address both of these issues, here we present morphologically complex nanocarriers in a hydratable powder form, which bypasses the need for expensive, harsh, and/or time-consuming nanocarrier fabrication techniques. The powders are composed of carbohydrates and self-assembling polymer amphiphiles having a low glass transition temperature. Hydration requires less than one minute and only involves the addition of aqueous media (water or saline) to rapidly obtain self-assembled micelles, worm-like micelles (i.e. filomicelles), or polymersomes from poly(ethylene glycol)-b-poly(propylene sulfide) (PEG-b-PPS) polymers. The formulated powders are highly stable, achieving hydration into monodisperse nanocarriers following >6 months of storage. Diverse drug cargoes were efficiently encapsulated during hydration, including hydrophobic small molecules for micellar morphologies, as well as individual and concurrent loading of both hydrophobic and hydrophilic molecules for vesicular morphologies. Hydrated polymersomes are shown to load hydrophilic biological macromolecules, and encapsulated enzymes retain bioactivity. Furthermore, we demonstrate that inclusion of lipid-anchored ligands in powder form permits the surface-display of targeting ligands and enhances target cell uptake, thereby extending this technology to targeted drug delivery applications. Our powder-based formulation strategy was extendable to commercially available polymer amphiphiles, including PEG-b-polystyrene and PEG-b-polycaprolactone. The formulated nanotechnologies described herein are highly modular, require minimal preparation, and remain stable in ambient long-term storage (bypassing cold chain requirements), which will enable their use in medicine (human and veterinary), research, and commercial applications from cosmetics to agriculture.

Culture media optimization for Chinese hamster ovary cell growth and expression of recombinant varicella-zoster virus glycoprotein E

Herpes zoster (HZ) is caused by reactivation of varicella-zoster virus (VZV) latent in the sensory ganglia and causes severe pain, often leading to postherpetic neuralgia (PHN). Two prophylactic vaccines against HZ are currently licensed for human use, a live attenuated vaccine and a subunit vaccine containing recombinant VZV glycoprotein E (gE) as antigen. The latter has superior protective efficacy against HZ and PHN. During HZ subunit vaccine development, we obtained Chinese hamster ovary (CHO) cell clones expressing VZV gE. This study was performed to optimize culture media conditions for CHO cell growth and gE production. Using a high-throughput culture system, three CHO cell clones were cultured in microtiter plates containing 24 different basal media, and three basal media were selected. The clone with the highest gE expression was fed-batch cultured in each of the three basal media in combination with 13 different feed media. A pair of media, BalanCD CHO Growth A and EX-CELL Advanced CHO Feed 1, with the highest productivity was selected for gE production. Scale-up fed-batch cultures of the selected clone cultured in a wave bag bioreactor containing the optimized media yielded 2440 mg gE protein/L culture, a 11.5-fold increase compared to original culture conditions (batch culture in CD OptiCHO medium). The optimized media condition is used to produce VZV gE antigen for an HZ subunit vaccine, which is under phase I clinical trial. This study would provide valuable insights on culture media optimization for CHO cells expressing a recombinant vaccine antigen.