Trends in Viral Vector-Based Vaccines for Tuberculosis: A Patent Review (2010-2023)

Tuberculosis (TB) is an ancient global public health problem. Several strategies have been applied to develop new and more effective vaccines against TB, from attenuated or inactivated mycobacteria to recombinant subunit or genetic vaccines, including viral vectors. This review aimed to evaluate patents filed between 2010 and 2023 for TB vaccine candidates. It focuses on viral vector-based strategies. A search was carried out in Espacenet, using the descriptors "mycobacterium and tuberculosis" and the classification A61K39. Of the 411 patents preliminarily identified, the majority were related to subunit vaccines, with 10 patents based on viral vector platforms selected in this study. Most of the identified patents belong to the United States or China, with a concentration of patent filings between 2013 and 2023. Adenoviruses were the most explored viral vectors, and the most common immunodominant Mycobacterium tuberculosis (Mtb) antigens were present in all the selected patents. The majority of patents were tested in mouse models by intranasal or subcutaneous route of immunization. In the coming years, an increased use of this platform for prophylactic and/or therapeutic approaches for TB and other diseases is expected. Along with this, expanding knowledge about the safety of this technology is essential to advance its use.

Improving Protection to Prevent Bacterial Infections: Preliminary Applications of Reverse Vaccinology against the Main Cystic Fibrosis Pathogens

Reverse vaccinology is a powerful tool that was recently used to develop vaccines starting from a pathogen genome. Some bacterial infections have the necessity to be prevented then treated. For example, individuals with chronic pulmonary diseases, such as Cystic Fibrosis, are prone to develop infections and biofilms in the thick mucus that covers their lungs, mainly caused by Burkholderia cepacia complex, Haemophilus influenzae, Mycobacterium abscessus complex, Pseudomonas aeruginosa and Staphylococcus aureus. These infections are complicated to treat and prevention remains the best strategy. Despite the availability of vaccines against some strains of those pathogens, it is necessary to improve the immunization of people with Cystic Fibrosis against all of them. An effective approach is to develop a broad-spectrum vaccine to utilize proteins that are well conserved across different species. In this context, reverse vaccinology, a method based on computational analysis of the genome of various microorganisms, appears as one of the most promising tools for the identification of putative targets for broad-spectrum vaccine development. This review provides an overview of the vaccines that are under development by reverse vaccinology against the aforementioned pathogens, as well as the progress made so far.

Modern vaccine strategies for emerging zoonotic viruses

INTRODUCTION

The significant increase in the emergence of notable zoonotic viruses in the previous decades has become a serious concern to global public health. Ninety-nine percent of infectious diseases have originated from zoonotic viruses with immense potential for dissemination, infecting the susceptible population completely lacking herd immunity.

AREAS COVERED

Zoonotic viruses appear in the last two decades as a major health threat either newly evolved or previously present with elevated prevalence in the last few years are selected to explain their current prophylactic measures. In this review, modern generation vaccines including viral vector vaccines, mRNA vaccines, DNA vaccines, synthetic vaccines, virus-like particles, and plant-based vaccines are discussed with their benefits and challenges. Moreover, the traditional vaccines and their efficacy are also compared with the latest vaccines.

EXPERT OPINION

The emergence and reemergence of viruses that constantly mutate themselves have greatly increased the chance of transmission and immune escape mechanisms in humans. Therefore, the only possible solution to prevent viral infection is the use of vaccines with improved safety profile and efficacy, which becomes the basis of modern generation vaccines.

COVID-19 and seasonal flu vaccination hesitancy: Links to personality and general intelligence in a large, UK cohort

Vaccines are a powerful and relatively safe tool to protect against a range of serious diseases. Nonetheless, a sizeable minority of people express 'vaccination hesitancy'. Accordingly, understanding the bases of this hesitancy represents a significant public health opportunity. In the present study we sought to examine the role of Big Five personality traits and general intelligence as predictors of vaccination hesitancy across two vaccination types in a large (N = 9667) sample of UK adults drawn from the Understanding Society longitudinal household study. We found that lower levels of general intelligence were associated with COVID-19 and seasonal flu vaccination hesitancy, and lower levels of neuroticism was associated with COVID-19 vaccination hesitancy. Although the self-reported reasons for being vaccine hesitant indicated a range of factors were important to people, lower general intelligence was associated with virtually all of these reasons. In contrast, Big Five personality traits showed more nuanced patterns of association.

The search for a Buruli Ulcer vaccine and the effectiveness of the Bacillus Calmette-Guérin vaccine

Buruli Ulcer is a neglected tropical disease that is caused by Mycobacterium ulcerans. It is not fatal; however, it manifests a range of devastating symptoms on the hosts' bodies. Various drugs and treatments are available for the disease; however, they are often costly and have adverse effects. There is still much uncertainty regarding the mode of transmission, vectors, and reservoir. At present, there are no official vector control methods, prevention methods, or a vaccine licensed to prevent infection. The Bacillus Calmette-Guérin vaccine developed against tuberculosis has some effectiveness against M. ulcerans. However, it is unable to induce long-lasting protection. Various types of vaccines have been developed based specifically against M. ulcerans; however, to date, none has entered clinical trials or has been released for public use. Additional awareness and funding are needed for research in this field and the development of more treatments, diagnostic tools, and vaccines.

Polymer-based nano-therapies to combat COVID-19 related respiratory injury: progress, prospects, and challenges

The recent coronavirus disease-2019 (COVID-19) outbreak has increased at an alarming rate, representing a substantial cause of mortality worldwide. Respiratory injuries are major COVID-19 related complications, leading to poor lung circulation, tissue scarring, and airway obstruction. Despite an in-depth investigation of respiratory injury's molecular pathogenesis, effective treatments have yet to be developed. Moreover, early detection of viral infection is required to halt the disease-related long-term complications, including respiratory injuries. The currently employed detection technique (quantitative real-time polymerase chain reaction or qRT-PCR) failed to meet this need at some point because it is costly, time-consuming, and requires higher expertise and technical skills. Polymer-based nanobiosensing techniques can be employed to overcome these limitations. Polymeric nanomaterials have the potential for clinical applications due to their versatile features like low cytotoxicity, biodegradability, bioavailability, biocompatibility, and specific delivery at the targeted site of action. In recent years, innovative polymeric nanomedicine approaches have been developed to deliver therapeutic agents and support tissue growth for the inflamed organs, including the lung. This review highlights the most recent advances of polymer-based nanomedicine approaches in infectious disease diagnosis and treatments. This paper also focuses on the potential of novel nanomedicine techniques that may prove to be therapeutically efficient in fighting against COVID-19 related respiratory injuries.

Glyconanoparticles as tools to prevent antimicrobial resistance

The increased phenomenon of antimicrobial resistance and the slow pace of development of new antibiotics are at the base of a global health concern regarding microbial infections. Antibiotic resistance kills an estimated 700,000 people each year worldwide, and this number is expected to increase dramatically if efforts are not made to develop new drugs or alternative containment strategies. Increased vaccination coverage, improved sanitation or sustained implementation of infection control measures are among the possible areas of action. Indeed, vaccination is one of the most effective tools of preventing infections. Starting from 1970s polysaccharide-based vaccines against Meningococcus, Pneumococcus and Haemophilus influenzae type b have been licensed, and provided effective protection for population. However, the development of safe and effective vaccines for infectious diseases with broad coverage remains a major challenge in global public health. In this scenario, nanosystems are receiving attention as alternative delivery systems to improve vaccine efficacy and immunogenicity. In this report, we provide an overview of current applications of glyconanomaterials as alternative platforms in the development of new vaccine candidates. In particular, we will focus on nanoparticle platforms, used to induce the activation of the immune system through the multivalent-displacement of saccharide antigens.

Current status and future directions of fish vaccines employing virus-like particles

In most breeding schemes, fish are cultured in enclosed spaces, which greatly increases the risk of outbreaks where the onset of infectious diseases can cause massive mortality and enormous economic losses. Vaccination is the most effective and long-term measure for improving the basic make-up of a fish farm. As the relationship between antibody and antigen is similar to that between screw and nut, similarity in the shape or nature of the vaccine antigen to the original pathogen is important for achieving a satisfactory/good/excellent antibody response with a vaccine. Virus-like particles (VLPs) best fulfil this requirement as their tertiary structure mimics that of the native virus. For this reason, VLPs have been attracting attention as next-generation vaccines for humans and animals, and the effects of various types of VLP vaccines on humans and livestock have been examined. Recent studies of VLP-based fish vaccines indicate that these vaccines are promising, and raise hopes of extending their use in the near future. In this review, the structural properties and immunogenicity of VLP-based vaccines against fish viruses such as infectious pancreatic necrosis virus (IPNV), salmonid alphavirus (SAV), nervous necrosis virus (NNV) and iridovirus are introduced/summarized. The NNV VLP vaccine is the most-studied VLP-based vaccine against fish viruses. Therefore, the current status of NNV VLP research is highlighted in this review, which deals with the advantages of using VLPs as vaccines, and the expression systems for producing them. Moreover, the need for lyophilized VLPs and oral VLP delivery is discussed. Finally, future directions for the development of VLP vaccines in the fish vaccine field are considered.