Vaccine Development Research Articles

Design and development of mRNA and self-amplifying mRNA vaccine nanoformulations.

The rapid evolution of mRNA vaccines, highlighted by Pfizer-BioNTech and Moderna's COVID-19 vaccines, has transformed vaccine development and therapeutic approaches. Self-amplifying mRNA (saRNA) vaccines, a groundbreaking advancement in RNA-based vaccines, offer promising possibilities for disease prevention and treatment, including potential applications in cancer and neurodegenerative diseases. This review explores the complex design and development of these innovative vaccines, with a focus on their nanoscale formulations that utilize nanotechnology to improve their delivery and effectiveness. It articulates the fundamental principles of mRNA and saRNA vaccines, their mechanisms of action, and the role of synthetic mRNA in eliciting immune responses. The review further elaborates on various nanoscale delivery systems (e.g., lipid nanoparticles, polymeric nanoparticles and other nanocarriers), emphasizing their advantages in enhancing mRNA stability and cellular uptake. It addresses advanced nanoscale delivery techniques such as microfluidics and discusses the challenges in formulating mRNA and saRNA vaccines. By incorporating the latest technologies and current research, this review provides a thorough overview of recent mRNA and saRNA nanovaccines advancements, highlighting their potential to revolutionize vaccine technology and broaden clinical applications.

A subunit vaccine based on P97R1, P46, P42, and P65 from Mycoplasma hyopneumoniae can induce significant immune response in piglets

Mycoplasma pneumonia (MPS), caused by Mycoplasma hyopneumoniae (Mhp), is a chronic, airborne respiratory disease that poses a significant threat to the global swine industry. The P97 and P46 proteins are major antigens of Mhp, with the R1 region of P97 possessing full adhesive capability. Studies have shown that the main antigenic regions of Mhp P42 and P65 proteins exhibit strong immunogenicity. In this study, we first linked the genes encoding P97R1 and P46 proteins to form the P97R1P65 gene and subsequently constructed three shuttle plasmids: pFBD-P97R1P46, pFBD-P97R1P46-p65, and pFBD-P65-P42. These proteins were expressed using the Bac to Bac system and formulated into subunit vaccines for mouse immunization. Mouse experiments indicated that the P97R1P46 + P65-P42 protein combination elicited higher levels of specific antibodies, IL-2, IL-4, and CD8+ T cells compared to other subunit vaccine groups, a finding further validated in subsequent mouse challenge protection experiments. Therefore, we utilized the MultiBac expression system to co-express P97R1P46, P65, and P42 proteins in the pFastMultibacDual vector for immunization experiments in piglets. The piglet immunization experiments demonstrated that the Mhp subunit vaccine prepared in this study could induce specific antibodies against Mhp, with the combination of P97R1P46, P65, and P42 proteins inducing the highest level of humoral immunity. This study provides valuable insights for the development of Mhp subunit vaccines.

Evaluation of the impact of hollow fiber pore size and membrane material on virus concentration using a handheld hollow fiber method.

Virus concentration using hollow fibers is widely used for vaccine production to maintain viral infectivity with low shear stress and to allow for easier scale-up of production. However, research laboratories often have limited available viral materials at the early stage of vaccine development, making it difficult to find an optimal hollow-fiber. In addition, few research articles have reported on optimizing hollow fiber pore size and membrane structure for virus concentration. In this study, the previously established handheld hollow fiber virus concentration method was modified to reduce the sample volume required and to enable simple and easy hollow fiber screening. The handheld hollow fiber screening method for virus concentration was confirmed to be effective using Zika as a model virus.

Refolding dynamics and immunoinformatic insights into Vibrio cholerae OmpA, OmpK, and OmpV for vaccine applications.

OmpA, OmpK, and OmpV are crucial for the pathogenesis of Vibrio cholerae, functioning within the bacterium's outer membrane; they present significant potential as candidates for vaccine development. Due to their intrinsic β-sheet richness, these OMPs tend to form inclusion bodies whenever overexpression is attempted. To achieve a native-like structure, detergents can be utilized during the refolding of OMPs from inclusion bodies. The impact of different detergents is examined on the renaturation of these OMPs, specifically non-ionic and zwitterionic detergents. The findings provide valuable insights into detergent selection, with LDAO and DDM emerging as the best protein refolding agents, facilitating successful structural and functional studies of these OMPs. Furthermore, using immunoinformatics it is established that OmpA, OmpK, and OmpV carry B- and T-cell epitopes in their exposed extracellular regions. The presence of immunodominant regions makes it easier to employ these proteins as vaccine candidates as they are stable, non-allergenic, and likely to stimulate successful innate and active immune responses. Overall, with all three OMPs harboring numerous immunogenic epitopes, they can be employed in subunit vaccines against Vibrio spp. and contribute to the development of diagnostic tools for effective disease mitigation.

Combination application of Pickering emulsion and BLS protein nanoparticles enhances vaccine efficacy.

The deficiency of recombinant protein immune response could be compensated for by using nanoparticle platforms or adding immune enhancers, however existing vaccines or adjuvants struggle to elicit durable cellular immune responses. In this work, a protein nanoscaffold, lumazine synthase isolated from Brucella (BLS) was optimally designed that could facilitate cellular uptake of displayed antigens and the maturation of bone marrow-derived dendritic cells (BMDCs), and enhancing humoral immune responses. To enhance cellular immune response, chitosan hydrochloride-stabilized Pickering emulsion (CHSPE) was evaluated as an adjuvant for the BLS nanoscaffold-based vaccine. CHSPE could enhance the recruitment and activation of DCs at the injection site and the uptake of antigen and activation of DCs in the draining lymph nodes (dLNs), compared with commercial adjuvant ISA 206. In addition, CHSPE induced antigen-specific antibody levels comparable to those of ISA 206 and increased the ratio of central memory T cells (TCM) and effector memory T cells (TEM), and promoted the secretion of Th1-type cytokines. Moreover, CHSPE-formulated vaccine provided a similar level of protection to the live attenuated vaccine and was superior to that of ISA 206. Taken together, the combination of the BLS nanoscaffold and CHSPE provides a feasible strategy for recombinant protein subunit vaccine development.

Dengue Virus Infection: Immune Response and Therapeutic Targets.

Flavivirus infection, especially dengue virus infection caused by DENV, is known to be a significant health concern globally owing to the high incidence and mortality rate. The expanding and increasing disease burden calls for the need to develop an effective treatment and prevent the event of fatal complications, including dengue hemorrhagic fever/dengue shock syndrome. The DENV-induced immune response has been described as paradoxical because it has a protective role in viral clearance but, at the same time, causes more severe infection through viral-specific immunity. This is further complicated by high homology and cross-reactivity between different serotypes of DENV, causing a more severe disease presentation during secondary infection by a heterologous serotype. This serotype complexity poses a challenge for the development of a universal flavivirus vaccine. This review highlights the significance of high motility group box 1 (HMGB1) and nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 3 (NLRP3) inflammasome activation pathways in initiating an inflammatory response through the downstream activation of nuclear factor κB and proinflammatory cytokine Interleukin (IL)-1B, IL-18 release in DENV infection. It also discusses the role of NLRP3 in activating cellular apoptosis and pyroptosis leading to systemic failure, especially in peripheral tissues. Over the decades, there has been much progress in understanding the immunopathogenesis of DENV infection. Researchers have been studying key pathogenic molecules for potential therapeutic targets including HMGB1 and NLRP3 inflammasome inhibitors, which is explored in this review. Ultimately, although there is not yet an effective antiviral or vaccine for DENV, immunomodulators continue to pave the way to decrease disease severity in infected individuals.

Identification of linear B cell epitopes on the E146L protein of African swine fever virus with monoclonal antibodies.

The outbreak and spread of African swine fever virus (ASFV) have caused considerable economic losses to the pig industry worldwide. Currently, to promote the development of effective ASF vaccines, especially subunit vaccines, more antigenic protein targets are urgently needed. In this work, six transmembrane proteins (I329L, E146L, C257L, EP153R, I177L, and F165R) were expressed in mammalian cell lines and screened with pig anti-ASFV serum. It was found that the E146L protein was an immunodominant protein antigen among the six selected proteins. Moreover, the E146L protein induced antibody responses in all immunized pigs. To gain insight into the antigenic characteristics of the E146L protein, three monoclonal antibodies (mAbs; 12H12, 15G1, and 15H10) were generated by immunizing BALB/c mice with the purified E146L protein. The epitopes of the mAbs were further finely mapped through a peptide fusion protein expression strategy. Finally, the epitopes of the mAbs were identified as 48PDESSIAYMRFRN61 of the mAb 12H12, 138TLTGLQRII146 of the mAb 15G1, and 30GWSPFKYSKGNT41 of the mAb 15H10. Furthermore, the epitope of mAb 15H10 was validated as the immunodominant epitope with ASFV-infected pig sera. The chemically synthesized mAb 15H10 epitope peptide (EP1) exhibited the most extensive immunoreactivity with artificially or naturally ASFV-infected pig sera. The epitope 15H10 is located on the surface of the E146L protein and is highly conserved. These findings provide insight into the structure and function of the E146L protein of ASFV.

Oral Bacillus subtilis spores-based vaccine for mass vaccination against porcine reproductive and respiratory syndrome.

Porcine reproductive and respiratory syndrome (PRRS) poses a significant challenge in the global swine industry, leading to substantial economic losses and reproductive and respiratory complications. The causative agent, PRRS virus (PRRSV), with its high mutation rate, complicates the development of universally effective vaccines. Furthermore, current PRRS vaccines are limited by high costs and complex administration methods. Therefore, in this study, we aimed to develop an innovative Bacillus subtilis spore-based oral vaccine targeting PRRS. Their oral administration was evaluated in mice and pigs, and blood, saliva, feces, and bronchoalveolar lavage fluid samples were collected for further analyses. Our vaccine induced IgG and IgA immune responses in both models, with swine demonstrating considerable increase in specific antibody and cytokine levels. These results indicate a high potential for more effective and economically viable control of PRRS in commercial pig farming. The ease of administration and cost-effectiveness of the vaccine also offer a feasible option for widespread application. Our results suggest a new direction in veterinary vaccine development, underscoring the potential of B. subtilis spores in creating effective vaccines for large-scale, real-world applications in animal health management.

Prophylactic and therapeutic vaccine development: advancements and challenges.

Biomedical research is fundamental in developing preventive and therapeutic vaccines, serving as a cornerstone of global public health. This review explores the key concepts, methodologies, tools, and challenges in the vaccine development landscape, focusing on transitioning from basic biomedical sciences to clinical applications. Foundational disciplines such as virology, immunology, and molecular biology lay the groundwork for vaccine creation, while recent innovations like messenger RNA (mRNA) technology and reverse vaccinology have transformed the field. Additionally, it highlights the role of pharmaceutical advancements in translating lab discoveries into clinical solutions. Techniques like CRISPR-Cas9, genome sequencing, monoclonal antibodies, and computational modeling have significantly enhanced vaccine precision and efficacy, expediting the development of vaccines against infectious diseases. The review also discusses challenges that continue to hinder progress, including stringent regulatory pathways, vaccine hesitancy, and the rapid emergence of new pathogens. These obstacles underscore the need for interdisciplinary collaboration and the adoption of innovative strategies. Integrating personalized medicine, nanotechnology, and artificial intelligence is expected to revolutionize vaccine science further. By embracing these advancements, biomedical research has the potential to overcome existing challenges and usher in a new era of therapeutic and prophylactic vaccines, ultimately improving global health outcomes. This review emphasizes the critical role of vaccines in combating current and future health threats, advocating for continued investment in biomedical science and technology.

Improving precision of vaccine efficacy evaluation using immune correlate data in time-to-event models.

Understanding potential differences in vaccine-induced protection between demographic subgroups is key for vaccine development. Vaccine efficacy evaluation across these subgroups in phase 2b or 3 clinical trials presents challenges due to lack of precision: such trials are typically designed to demonstrate overall efficacy rather than to differentiate its value between subgroups. This study proposes a method for estimating vaccine efficacy using immunogenicity (instead of vaccination status) as a predictor in time-to-event models. The method is applied to two datasets from immunogenicity sub-studies of vaccine phase 3 clinical trials for zoster and dengue vaccines. Results show that using immunogenicity-based estimation of efficacy in subgroups using time-to-event models is more precise than the standard estimation. Incorporating immune correlate data in time-to-event models improves precision in estimating efficacy (i.e., yields narrower confidence intervals), which can assist vaccine developers and public health authorities in making informed decisions.

Understanding the COVID-19 vaccine uptake, acceptance, and hesitancy in Ethiopia and Tanzania: a scoping review

BackgroundThe development and implementation of COVID-19 vaccines have been a breakthrough in controlling the pandemic. However, the vaccination coverage in most low-income countries remains very low due to critical vaccine shortage and profound hesitancy. In this scoping review, we aimed to assess COVID-19 vaccine uptake, acceptance, and hesitancy in Ethiopia and Tanzania.MethodsThe search was made in PubMed, Scopus, Embase, and Web of Science. Only original research articles focusing on vaccine acceptance and hesitancy were included. The studies selected for a full read were analysed using a thematic analysis approach.FindingsA total of 76 articles were included in the study, with 74 of them coming from Ethiopia. The study found an increasing trend in vaccine uptake over time. However, there was also an increase in hesitancy and a decline in willingness to receive the vaccine. The willingness to receive the COVID-19 vaccine in Ethiopia ranged from 18.5 to 88%. The main reasons for "vaccine hesitancy" included fear of side effects, concerns about long-term safety, doubts about vaccine effectiveness, lack of information, vaccine fast-tracking, and religious beliefs. The study also found that younger individuals, females, and pregnant women were less willing to receive the vaccine. The adverse events reported among vaccinated individuals were mostly mild. Most of the studies operationalised vaccine acceptance-hesitancy as dichotomous variables. However, the historical, political, and socio-cultural context in which vaccine acceptance and hesitancy occur was not given any attention. While there is a good amount of data from Ethiopia describing patterns of vaccine acceptance and hesitancy among different populations over time, there is limited information from Tanzania due to the late arrival of the vaccine and limited published articles.ConclusionWe have observed a paradox involving two seemingly conflicting trends: an increase in vaccination rates/coverage and "anti-vax." Most studies have simplified vaccine acceptance-hesitancy as an “either-or” incident, without considering its dynamic nature and occurrence within a broader political, social, and cultural context. Therefore, it is crucial to explore approaches that can enhance our understanding of the vaccine acceptance-hesitancy phenomenon, in order to improve vaccine trust and uptake.

ORGANIZATION OF METHODOLOGICAL PRINCIPLES OF THE STATE INNOVATION POLICY IN THE SPHERE OF INFORMATIZATION OF THE HEALTH PROTECTION SYSTEM OF UKRAINE

The article highlights the key issues related to the need to modernize the health care system, globalization and integration into international structures, health care reform. In Ukraine, the process of health care reform is underway, which involves increasing the efficiency of the medical services system, their availability and quality. Innovations can accelerate these processes, in particular through the introduction of digital technologies (e-health, telemedicine), automation of management of medical facilities, development of remote diagnosis and treatment. The state innovation policy will allow to more effectively prepare for similar challenges in the future through the development of new vaccines, diagnostic methods, monitoring systems and management of medical resources. Support from the state (for example, through preferential taxation) to the development of the private medical services sector will reduce the burden on the state budget. In addition, it contributes to the attraction of investments in this area. Therefore, the state innovation policy in the field of health care is a relevant tool for ensuring the sustainable development of the health care system of Ukraine, increasing its efficiency and competitiveness, which meets the modern challenges and needs of society. The authors analyze the key aspects of the state policy aimed at the informatization of medical institutions, in particular, the digitalization of medical services, the introduction of electronic medicine, the creation of unified information platforms and patient databases. The article examines the importance of developing a clear methodology for the implementation of innovative solutions, as well as the role of the state in creating favorable conditions for the informatization of the health care system. The authors also analyze the international experience and the possibilities of its adaptation for Ukrainian realities, emphasizing the need to establish effective cooperation between state bodies, medical institutions and technological companies. The article concludes about the importance of an integrated approach to the informatization of the health care sector in order to improve the quality of medical services and increase the efficiency of medical resource management.

Understanding American tegumentary leishmaniasis in urban Montes Claros, Brazil: insights from clinical, immunological and therapeutic investigations.

The challenge of American tegumentary leishmaniasis (ATL) continues in Brazil, presenting a persistent public health issue despite initiatives aimed at public outreach, vector control and health education. To gain a deeper understanding of this disease, a study was conducted in an endemic region located in the northern region of the state of Minas Gerais, Brazil. The study monitored 30 resident patients diagnosed with ATL, using serum samples from 6 healthy individuals as controls. The localized cutaneous form of the disease was found to be predominant, with lesions appearing on various parts of the body and the majority of the affected individuals being male. The study found significantly higher levels of IgG anti-α-Gal antibodies in ATL-infected patients compared to healthy individuals. Treatment of 19 patients with meglumine antimoniate resulted in limited improvement in symptoms for most. Nonetheless, the study found that 12 patients who completed treatment with epithelialization of the lesions showed a significant decrease in IgG anti-α-Gal antibodies, indicating potential applications of this antibody in the diagnosis and monitoring of the disease. The study also identified Leishmania species in 7 analysed patients, revealing 6 cases infected by Leishmania braziliensis and 1 by L. infantum, with a significant difference in the anti-α-Gal responses. The findings of the study emphasize the urgent need for the development of human vaccines and innovative treatment strategies adapted to the diversity of Leishmania species causing cutaneous leishmaniasis and individual patient responses to improve the clinical management of ATL in Brazil and similar endemic regions.

Harnessing Bacillus subtilis Spore Surface Display (BSSD) Technology for Mucosal Vaccines and Drug Delivery: Innovations in Respiratory Virus Immunization

Respiratory viruses present significant global health challenges due to their rapid evolution, efficient transmission, and zoonotic potential. These viruses primarily spread through aerosols and droplets, infecting respiratory epithelial cells and causing diseases of varying severity. While traditional intramuscular vaccines are effective in reducing severe illness and mortality, they often fail to induce sufficient mucosal immunity, thereby limiting their capacity to prevent viral transmission. Mucosal vaccines, which specifically target the respiratory tract’s mucosal surfaces, enhance the production of secretory IgA (sIgA) antibodies, neutralize pathogens, and promote the activation of tissue-resident memory B cells (BrMs) and local T cell responses, leading to more effective pathogen clearance and reduced disease severity. Bacillus subtilis spore surface display (BSSD) technology is emerging as a promising platform for the development of mucosal vaccines. By harnessing the stability and robustness of Bacillus subtilis spores to present antigens on their surface, BSSD technology offers several advantages, including enhanced stability, cost-effectiveness, and the ability to induce strong local immune responses. Furthermore, the application of BSSD technology in drug delivery systems opens new avenues for improving patient compliance and therapeutic efficacy in treating respiratory infections by directly targeting mucosal sites. This review examines the potential of BSSD technology in advancing mucosal vaccine development and explores its applications as a versatile drug delivery platform for combating respiratory viral infections.

A Brief Chronicle of Antibody Research and Technological Advances

This review briefly traces the historical development of antibody research and related technologies. The path from early perceptions of immunity to the emergence of modern immunotherapy has been marked by pivotal discoveries and technological advances. Early insights into immunity led to the development of vaccination and serotherapy. The elucidation of antibody structure and function paved the way for monoclonal antibody technology and its application in diagnosis and therapy. Breakthroughs in genetic engineering have enabled the production of humanized antibodies and the advances in Fc engineering, thereby increasing therapeutic efficacy. The discovery of immune checkpoints and cytokines revolutionized the treatment of cancer and autoimmune diseases. The field continues to evolve rapidly with the advent of antibody–drug conjugates, bispecific antibodies, and CAR T-cell therapies. As we face global health challenges, antibody research remains at the forefront of medical innovation and offers promising solutions for the future.

INNV-18. FOCUS ON CURRENT AND EMERGING TREATMENT OPTIONS FOR GLIOMA: A COMPREHENSIVE REVIEW

Abstract This comprehensive review delves into the current updates and challenges associated with the management of low-grade gliomas (LGG), the predominant primary tumors in the central nervous system. With a general incidence rate of 5.81 per 100000, gliomas pose a significant global concern, necessitating advancements in treatment techniques to reduce mortality and morbidity. This review places a particular focus on immunotherapies, discussing promising agents such as Zotiraciclib and Lerapolturev. Zotiraciclib, a CDK9 inhibitor, has demonstrated efficacy in glioblastoma treatment in preclinical and clinical studies, showing its potential as a therapeutic breakthrough. Lerapolturev, a viral immunotherapy, induces inflammation in glioblastoma and displays positive outcomes in both adult and pediatric patients. Exploration of immunotherapy extends to Pembrolizumab, Nivolumab, and Entrectinib, revealing the challenges and variabilities in patient responses. Despite promising preclinical data, the monoclonal antibody Depatuxizumab has proven ineffective in glioblastoma treatment, emphasizing the critical need to understand resistance mechanisms. The review also covers the success of radiation therapy in pediatric LGG, with evolving techniques, such as proton therapy, showing potential improvements in patient quality of life. Surgical treatment is discussed in the context of achieving a balance between preserving the patient’s quality of life and attaining gross total resection, with the extent of surgical resection significantly influencing the survival outcomes. In addition to advancements in cancer vaccine development, this review highlights the evolving landscape of LGG treatment, emphasizing a shift toward personalized and targeted therapies. Ongoing research is essential for refining strategies and enhancing outcomes in the management of LGG.

Structure-guided design and evaluation of CRM197-scaffolded vaccine targeting GnRH for animal immunocastration

Immunocastration is a humane alternative to surgical castration for controlling population and estrous behaviors in animals. Gonadotropin-releasing hormone (GnRH), the pivotal initiating hormone of the hormonal cascade in mammals, is the optimal target for immunocastration vaccine development. Cognate antigen-mediated cross-linking of B cell receptors (BCRs) is a strong activation signal for B cells and is facilitated by repetitive surface organizations of antigens. In this study, we describe the structure-guided design of highly immunogenic chimeric proteins with variant numbers of GnRH peptide insertion by epitope grafting. Linear B-cell epitopes of cross-reacting material 197 (CRM197) were replaced with multiple copies of GnRH peptide, and the inserts were displayed on the surface of the designs while maintaining the overall folding of CRM197. Among the seven designs, TCG13, which carries 13 copies of GnRH peptide, was the most immunogenic, and its immunocastration efficacy was evaluated in male mice. Vaccination with the BFA03-adjuvanted TCG13 induced potent humoral immunity and reduced the serum testosterone concentration in mice. It could significantly decrease sperm quality and severely impair gonadal function and fertility. These results demonstrate that CRM197 holds great value as a scaffold for epitope presentation in peptide-based vaccine development and supports TCG13 as a promising vaccine candidate for animal immunocastration.Key points• Provide a feasible way to design chimeric immunogen targeting GnRH by epitope grafting.• CRM197 can accommodate the insertion of multiple copies of heterologous epitope peptides.• Administration with the most immunogenic design led to effective immunocastration in male mice.

GelMA microneedle-loaded bio-derived nanovaccine shows therapeutic potential for gliomas

ABSTRACT Glioma is the most common primary malignant tumor of the central nervous system in adults. Although immunotherapy, especially tumor vaccines, has made some progress in the treatment of gliomas compared with surgery and radiotherapy. However, the lack of specific or relevant tumor antigens severely limits the further development of tumor vaccines. Here, we report a bio-derived vaccine (TMV@CpG) derived from glioma cell membrane vesicles and carrying TLR9 agonist CpG as adjuvant, which was loaded onto the GelMA microneedle to obtain the microneedle vaccine (MN-TMV@CpG). Microneedle vaccine fully utilize the innate immune cells rich in the skin, inducing stronger cellular immune responses. In subcutaneous tumor models, MN-TMV@CpG reversed the immune-suppressing microenvironment of tumor, and effectively inhibited tumor progression. In an intracranial tumor model, MN-TMV@CpG significantly prolonged the survival duration and induced stronger immune memory responses in tumor bearing mice when combined with anti-PD1 mAb. These results suggest that bio-derived nanovaccines can be used as a potential antitumor immunotherapy strategy.

A Cap-Optimized mRNA Encoding Multiepitope Antigen ESAT6 Induces Robust Cellular and Humoral Immune Responses Against Mycobacterium tuberculosis

Background/Objectives. Tuberculosis is a deadly bacterial disease and the second most common cause of death from monoinfectious diseases worldwide. Comprehensive measures taken by health authorities in various countries in recent decades have saved tens of millions of lives, but the number of new cases of this infection has been steadily increasing in the last few years and already exceeds 10 million new cases annually. The development of new vaccines against tuberculosis is a priority area in the prevention of new cases of the disease. mRNA vaccines have already shown high efficacy against COVID-19 and other viral infections and can currently be considered a promising field of antituberculosis vaccination. In our previous study, we assessed the immunogenicity and protective activity of several types of antituberculosis mRNA vaccines with different 5′ untranslated regions, but the efficacy of these vaccines was either comparable with or lower than that of BCG. Methods. Here, we conducted a comprehensive experiment to investigate the effects of cotranscriptional capping conditions and of cap structure on the magnitude of the mRNAs’ translation in HEK293T and DC2.4 cells. The most effective cap version was used to create an antituberculosis mRNA vaccine called mEpitope-ESAT6. Results and Conclusions. We compared immunogenicity and protective activity between mEpitope-ESAT6 and BCG and found that the vaccine with the new cap type is more immunogenic than BCG. Nonetheless, the increased immunogenicity did not enhance vaccine-induced protection. Thus, the incorporation of different cap analogs into mRNA allows to modulate the efficacy of mRNA vaccines.

Variability of non-structural proteins of HIV-1 sub-subtype A6 (Retroviridae: Orthoretrovirinae: Lentivirus: Human immunodeficiency virus-1, sub-subtype A6) variants circulating in different regions of the Russian Federation.

HIV-1 non-structural proteins are promising targets for vaccine development and for creating approaches to personalized medicine. HIV-1 sub-subtype A6 has become the dominating strain in Russia. However, the geographic, economic and demographic characteristics of the country can contribute to the formation of differences between A6 variants circulating in different regions. The aim of the study is a comparative analysis of the consensus sequences of non-structural proteins in A6 variants circulating in the Amur Region, in Arkhangelsk, Irkutsk and Murmansk. 48 whole blood samples obtained from HIV-infected patients without experience of therapy observed at the AIDS Centers in Arkhangelsk, Irkutsk, Murmansk and Amur Region were analyzed. HIV-1 whole-genome nucleotide sequences were obtained and were subtyped. Consensus sequences of sub-subtype A6 variants non-structural proteins for each analyzed region were formed. Furthermore, reference sequences of sub-subtype A6 non-structural proteins were formed based on whole-genome sequences retrieved from the international Los Alamos database. Comparison of consensus sequences and references was performed using the MEGA v.10.2.2 and the PSIPRED programs. Vif, Vpr and Nef reference sequences have been obtained for HIV-1 sub-subtype A6. There was not difference in consensus sequences of Vpr in different regions. Characteristic features were found for consensus sequences of Tat, Rev, Vpu, Vif and Nef proteins in different regions. A limitation of the study is a small sample size. Overall, the results demonstrate the existing diversity of non-structural proteins in sub-subtype A6 variants in different regions and indicate the relevance of studying the polymorphism of non-structural proteins of virus variants in different regions.