Dendrimer-RNA nanoparticles generate protective immunity against lethal Ebola, H1N1 influenza, and Toxoplasma gondii challenges with a single dose

Emerging mRNA Technology for Liver Disease Therapy

Liver diseases have consistently posed substantial challenges to global health. It is crucial to find innovative methods to effectively prevent and treat these diseases. In recent times, there has been an increasing interest in the use of mRNA formulations that accumulate in liver tissue for the treatment of hepatic diseases. In this review, we start by providing a detailed introduction to the mRNA technology. Afterward, we highlight types of liver diseases, discussing their causes, risks, and common therapeutic strategies. Additionally, we summarize the latest advancements in mRNA technology for the treatment of liver diseases. This includes systems based on hepatocyte growth factor, hepatitis B virus antibody, left-right determination factor 1, human hepatocyte nuclear factor α, interleukin-12, methylmalonyl-coenzyme A mutase, etc. Lastly, we provide an outlook on the potential of mRNA technology for the treatment of liver diseases, while also highlighting the various technical challenges that need to be addressed. Despite these difficulties, mRNA-based therapeutic strategies may change traditional treatment methods, bringing hope to patients with liver diseases.

Advancing mRNA Therapeutics: The Role and Future of Nanoparticle Delivery Systems

The coronavirus (COVID-19) pandemic has underscored the critical role of mRNA-based vaccines as powerful, adaptable, readily manufacturable, and safe methodologies for prophylaxis. mRNA-based treatments are emerging as a hopeful avenue for a plethora of conditions, encompassing infectious diseases, cancer, autoimmune diseases, genetic diseases, and rare disorders. Nonetheless, the in vivo delivery of mRNA faces challenges due to its instability, suboptimal delivery, and potential for triggering undesired immune reactions. In this context, the development of effective drug delivery systems, particularly nanoparticles (NPs), is paramount. Tailored with biophysical and chemical properties and susceptible to surface customization, these NPs have demonstrated enhanced mRNA delivery in vivo and led to the approval of several NPs-based formulations for clinical use. Despite these advancements, the necessity for developing a refined, targeted NP delivery system remains imperative. This review comprehensively surveys the biological, translational, and clinical progress in NPs-mediated mRNA therapeutics for both the prevention and treatment of diverse diseases. By addressing critical factors for enhancing existing methodologies, it aims to inform the future development of precise and efficacious mRNA-based therapeutic interventions.

In vitro and ex vivo protoscolicidal effect of poly(amidoamine) nanoemulsion against Echinococcus granulosus

Hydatidosis causes a serious health hazard to humans and animals leading to significant economic and veterinary and public health concern worldwide. The present study aimed to evaluate the in vitro and ex vivo protoscolicidal effects of synthesized poly(amidoamine), PAMAM, nanoemulsion. In this study, PAMAM was characterized through dynamic light scattering technique to investigate the particle size and zeta potential of nanoemulsified polymer. For the in vitro and ex vivo assays, we used eosin dye exclusion test and scanning electron microscope (SEM) to evaluate the effects of the prepared and characterized PAMAM nanoemulsion against protoscoleces from Echinococcus granulosus sensu lato G6 (GenBank: OQ443068.1) isolated from livers of naturally infected camels. Various concentrations (0.5, 1, 1.5 and 2 mg/mL) of PAMAM nanoemulsion at different exposure times (5, 10, 20 and 30 min) were tested against protoscolices. Our findings showed that PAMAM nanoemulsion had considerable concentration- and time-dependent protoscolicidal effect at both in vitro and ex vivo experiments. Regarding in vitro assay, PAMAM nanoemulsion had a potent protoscolicidal effect when compared with the control group with a highest protoscolicidal activity observed at the concentration of 2 mg/mL at all exposure times, such that 100% of protoscolices were killed after 20 min of exposure. Also, the mortality of protoscolices was 100% after 30 min of exposure to 1 and 1.5 mg/mL of PAMAM nanoemulsion, in vitro. Concerning ex vivo assay PAMAM nanoemulsion recorded the highest mortality rates at the concentration of 2 mg/mL (55, 99.4 and 100% at 10, 20, 30 min, respectively). Ultrastructure examination of examined protoscolices after 20 min of exposure to PAMAM nanoemulsion showed a complete loss of rostellar hooks, disruption of suckers with disorganization of hooks with partial or complete loss of them, and damage of protoscolices tegument with loss of their integrity in the form of holes and contraction of the soma region were observed in 1.5 and 2 mg/mL of PAMAM, in vitro and ex vivo, showing more damage in the in vitro conditions. It can be concluded that PAMAM nanoemulsion is a promising protoscolicidal agent offering a high protoscolicidal effect at a short exposure time. Further in vivo studies and preclinical animal trials are required to evaluate its efficacy and clinical applications against hydatid cysts.

mRNA vaccines against infectious diseases and future direction

Vaccines are used for the control of infectious diseases of animals. Over other types of vaccinations like live attenuated or killed vaccines, mRNA-based vaccines have significant advantages. As only a small portion of the pathogen's genetic material is employed and the dose rate of mRNA-based vaccines is low, there is the least possibility that the pathogen will reverse itself. A carrier or vehicle that shields mRNA-based vaccines from the host's cellular RNases is necessary for their delivery. mRNA vaccines have been shown to be effective and to induce both a cell-mediated immune response and a humoral immune response in clinical trials against various infectious diseases (viral and parasitic) affecting the animals, including rabies, foot and mouth disease, toxoplasmosis, Zikavirus, leishmaniasis, and COVID-19. The current review aims to highlight the use of mRNA-based vaccines both in viral and parasitic diseases of animals.

COVID-19 Variants and Vaccine Development

Coronavirus disease 2019 (COVID-19), the global pandemic caused by severe acute respiratory syndrome 2 virus (SARS-CoV-2) infection, has caused millions of infections and fatalities worldwide. Extensive SARS-CoV-2 research has been conducted to develop therapeutic drugs and prophylactic vaccines, and even though some drugs have been approved to treat SARS-CoV-2 infection, treatment efficacy remains limited. Therefore, preventive vaccination has been implemented on a global scale and represents the primary approach to combat the COVID-19 pandemic. Approved vaccines vary in composition, although vaccine design has been based on either the key viral structural (spike) protein or viral components carrying this protein. Therefore, mutations of the virus, particularly mutations in the S protein, severely compromise the effectiveness of current vaccines and the ability to control COVID-19 infection. This review begins by describing the SARS-CoV-2 viral composition, the mechanism of infection, the role of angiotensin-converting enzyme 2, the host defence responses against infection and the most common vaccine designs. Next, this review summarizes the common mutations of SARS-CoV-2 and how these mutations change viral properties, confer immune escape and influence vaccine efficacy. Finally, this review discusses global strategies that have been employed to mitigate the decreases in vaccine efficacy encountered against new variants.

Harnessing T-Cells for Enhanced Vaccine Development against Viral Infections

Despite significant strides in vaccine research and the availability of vaccines for many infectious diseases, the threat posed by both known and emerging infectious diseases persists. Moreover, breakthrough infections following vaccination remain a concern. Therefore, the development of novel vaccines is imperative. These vaccines must exhibit robust protective efficacy, broad-spectrum coverage, and long-lasting immunity. One promising avenue in vaccine development lies in leveraging T-cells, which play a crucial role in adaptive immunity and regulate immune responses during viral infections. T-cell recognition can target highly variable or conserved viral proteins, and memory T-cells offer the potential for durable immunity. Consequently, T-cell-based vaccines hold promise for advancing vaccine development efforts. This review delves into the latest research advancements in T-cell-based vaccines across various platforms and discusses the associated challenges.

Engineered mRNA Delivery Systems for Biomedical Applications

Messenger RNA (mRNA)-based therapeutic strategies have shown remarkable promise in preventing and treating a staggering range of diseases. Optimizing the structure and delivery system of engineered mRNA has greatly improved its stability, immunogenicity, and protein expression levels, which has led to a wider range of uses for mRNA therapeutics. Herein, a thorough analysis of the optimization strategies used in the structure of mRNA is first provided and delivery systems are described in great detail. Furthermore, the latest advancements in biomedical engineering for mRNA technology, including its applications in combatting infectious diseases, treating cancer, providing protein replacement therapy, conducting gene editing, and more, are summarized. Lastly, a perspective on forthcoming challenges and prospects concerning the advancement of mRNA therapeutics is offered. Despite these challenges, mRNA-based therapeutics remain promising, with the potential to revolutionize disease treatment and contribute to significant advancements in the biomedical field.

Advanced nanoscale delivery systems for mRNA-based vaccines

The effectiveness of messenger RNA (mRNA) vaccines, especially those designed for COVID-19, relies heavily on sophisticated delivery systems that ensure efficient delivery of mRNA to target cells. A variety of nanoscale vaccine delivery systems (VDSs) have been explored for this purpose, including lipid nanoparticles (LNPs), liposomes, and polymeric nanoparticles made from biocompatible polymers such as poly(lactic-co-glycolic acid), as well as viral vectors and lipid-polymer hybrid complexes. Among these, LNPs are particularly notable for their efficiency in encapsulating and protecting mRNA. These nanoscale VDSs can be engineered to enhance stability and facilitate uptake by cells. The choice of delivery system depends on factors like the specific mRNA vaccine, target cell types, stability requirements, and desired immune response. In this review, we shed light on recent advances in delivery mechanisms for self-amplifying RNA (saRNA) vaccines, emphasizing groundbreaking studies on nanoscale delivery systems aimed at improving the efficacy and safety of mRNA/saRNA vaccines.

mRNA Delivery: Challenges and Advances through Polymeric Soft Nanoparticles

Single-stranded messenger ribonucleic acid (mRNA) plays a pivotal role in transferring genetic information, and tremendous effort has been devoted over the years to utilize its transcription efficacy in therapeutic interventions for a variety of diseases with high morbidity and mortality. Lipid nanocarriers have been extensively investigated for mRNA delivery and enabled the rapid and successful development of mRNA vaccines against SARS-CoV-2. Some constraints of lipid nanocarriers have encouraged the development of alternative delivery systems, such as polymer-based soft nanoparticles, which offer a modular gene delivery platform. Such macromolecule-based nanocarriers can be synthetically articulated for tailored parameters including mRNA protection, loading efficacy, and targeted release. In this review, we highlight recent advances in the development of polymeric architectures for mRNA delivery, their limitations, and the challenges that still exist, with the aim of expediting further research and the clinical translation of such formulations.

Unlocking Delivery Strategies for mRNA Therapeutics

mRNA emerged as an attractive therapy modality with the development of mRNA structure engineering techniques and delivery platforms. mRNA therapeutics, applied for vaccine therapy, protein replacement therapy, and chimeric antigen receptor (CAR) T cell-based therapy, has shown huge potential in treating a wide range of diseases, such as cancer and rare genetic diseases, with successful and exciting preclinical and clinical progress. In mRNA therapeutics, a potent delivery system is key to the success of its application for disease treatment. Herein, different types of mRNA delivery strategies, including nanoparticles produced from lipid or polymer materials, virus-based platforms, and exosome-based platforms, are mainly focused.

Nanoparticle technology for mRNA: Delivery strategy, clinical application and developmental landscape

The mRNA vaccine, a groundbreaking advancement in the field of immunology, has garnered international recognition by being awarded the prestigious Nobel Prize, which has emerged as a promising prophylactic and therapeutic modality for various diseases, especially in cancer, rare disease, and infectious disease such as COVID-19, wherein successful mRNA treatment can be achieved by improving the stability of mRNA and introducing a safe and effective delivery system. Nanotechnology-based delivery systems, such as lipid nanoparticles, lipoplexes, polyplexes, lipid-polymer hybrid nanoparticles and others, have attracted great interest and have been explored for mRNA delivery. Nanoscale platforms can protect mRNA from extracellular degradation while promoting endosome escape after endocytosis, hence improving the efficacy. This review provides an overview of diverse nanoplatforms utilized for mRNA delivery in preclinical and clinical stages, including formulation, preparation process, transfection efficiency, and administration route. Furthermore, the market situation and prospects of mRNA vaccines are discussed here.

RNA-Based Vaccines and Therapeutics Against Intracellular Pathogens

RNA-based vaccines have sparked a paradigm shift in the treatment and prevention of diseases by nucleic acid medicines. There has been a notable surge in the development of nucleic acid therapeutics and vaccines following the global approval of the two messenger RNA-based COVID-19 vaccines. This growth is fueled by the exploration of numerous RNA products in preclinical stages, offering several advantages over conventional methods, i.e., safety, efficacy, scalability, and cost-effectiveness. In this chapter, we provide an overview of various types of RNA and their mechanisms of action for stimulating immune responses and inducing therapeutic effects. Furthermore, this chapter delves into the varying delivery systems, particularly emphasizing the use of nanoparticles to deliver RNA. The choice of delivery system is an intricate process involved in developing nucleic acid medicines that significantly enhances their stability, biocompatibility, and site-specificity. Additionally, this chapter sheds light on the current landscape of clinical trials of RNA therapeutics and vaccines against intracellular pathogens.

Nano-bio interactions in mRNA nanomedicine: Challenges and opportunities for targeted mRNA delivery

Upon entering the biological milieu, nanomedicines swiftly interact with the surrounding tissue fluid, subsequently being enveloped by a dynamic interplay of biomacromolecules, such as carbohydrates, nucleic acids, and cellular metabolites, but with predominant serum proteins within the biological corona. A notable consequence of the protein corona phenomenon is the unintentional loss of targeting ligands initially designed to direct nanomedicines toward particular cells or organs within the in vivo environment. mRNA nanomedicine displays high demand for specific cell and tissue-targeted delivery to effectively transport mRNA molecules into target cells, where they can exert their therapeutic effects with utmost efficacy. In this review, focusing on the delivery systems and tissue-specific applications, we aim to update the nanomedicine population with the prevailing and still enigmatic paradigm of nano-bio interactions, a formidable hurdle in the pursuit of targeted mRNA delivery. We also elucidate the current impediments faced in mRNA therapeutics and, by contemplating prospective avenues-either to modulate the corona or to adopt an 'ally from adversary' approach-aim to chart a course for advancing mRNA nanomedicine.

RNA Combined with Nanoformulation to Advance Therapeutic Technologies

Nucleic acid-based therapies have the potential to address numerous diseases that pose significant challenges to more traditional methods. RNA-based therapies have emerged as a promising avenue, utilizing nanoformulation treatments to target a range of pathologies. Nanoformulation offers several advantages compared to other treatment modalities, including targeted delivery, low toxicity, and bioactivity suitable for drug loading. At present, various types of nanoformulations are available, such as liposomes, polymeric nanoparticles (NPs), magnetic NPs, nanoshells, and solid lipid nanoparticles (SLNs). RNA-based therapy utilizes intracellular gene nanoparticles with messenger RNA (mRNA) emerging prominently in cancer therapy and immunotechnology against infectious diseases. The approval of mRNA-based technology opens doors for future technological advancements, particularly self-amplifying replicon RNA (repRNA). RepRNA is a novel platform in gene therapy, comprising viral RNA with a unique molecular property that enables the amplification of all encoded genetic information countless times. As a result, repRNA-based therapies have achieved significant levels of gene expression. In this context, the primary objective of this study is to furnish a comprehensive review of repRNA and its applications in nanoformulation treatments, with a specific focus on encapsulated nanoparticles. The overarching goal is to provide an extensive overview of the use of repRNA in conjunction with nanoformulations across a range of treatments and therapies.

Poly(2-oxazoline)/saRNA Polyplexes for Targeted and Nonviral Gene Delivery

RNA delivery has been demonstrated to be a potent method of vaccine delivery, as demonstrated by the recent success of the COVID-19 vaccines. Polymers have been shown to be effective vehicles for RNA delivery, with poly(ethylene imine) (PEI) being the current gold standard for delivery. Nonetheless, PEI has toxicity concerns, and so finding alternatives is desirable. Poly(2-oxazoline)s are a promising alternative to PEI, as they are generally biocompatible and offer a high degree of control over the polymer structure. Here, we have synthesized an ionizable primary amine 2-oxazoline and combined it with a double bond containing oxazoline to synthesize a small library of charged statistical and block copolymers. The pendant double bonds were reacted further to decorate the polymers with glucose via a thiol-ene click reaction. All polymers were shown to have excellent cell viability, and the synthesized block polymers showed promising complexation efficiencies for the saRNA, demonstrating a clear structure-property relationship. The polymer transfection potential was tested in various cell lines, and a polymer composition with an amine/glucose ratio of 9:27 has demonstrated the best transfection potential across all cell lines tested. Overall, the results suggest that block polymers with a cationic segment and high levels of glycosylation have the best complexation efficiency and RNA expression levels.

Drug delivery systems for CRISPR-based genome editors

CRISPR-based drugs can theoretically manipulate any genetic target. In practice, however, these drugs must enter the desired cell without eliciting an unwanted immune response, so a delivery system is often required. Here, we review drug delivery systems for CRISPR-based genome editors, focusing on adeno-associated viruses and lipid nanoparticles. After describing how these systems are engineered and their subsequent characterization in preclinical animal models, we highlight data from recent clinical trials. Preclinical targeting mediated by polymers, proteins, including virus-like particles, and other vehicles that may deliver CRISPR systems in the future is also discussed.

Immune system roles in pathogenesis, prognosis, control, and treatment of Toxoplasma gondii infection

Toxoplasma gondii is the protozoan causative agent of toxoplasmosis in humans and warm-blooded animals. Recent studies have illustrated that the immune system plays a pivotal role in the pathogenesis of toxoplasmosis by triggering immune cytokines like IL-12, TNF-α, and IFN-γ and immune cells like DCs, Th1, and Th17. On the other hand, some immune components can serve as prognosis markers of toxoplasmosis. In healthy people, the disease is often asymptomatic, but immunocompromised people and newborns may suffer severe symptoms and complications. Therefore, the immune prognostic markers may provide tools to measure the disease progress and help patients to avoid further complications. Immunotherapies using monoclonal antibody, cytokines, immune cells, exosomes, novel vaccines, and anti-inflammatory molecules open new horizon for toxoplasmosis treatment. In this review article, we discussed the immunopathogenesis, prognosis, and immunotherapy of Toxoplasma gondii infection.

A Rift Valley fever mRNA vaccine elicits strong immune responses in mice and rhesus macaques

Rift Valley fever virus (RVFV) is listed as a priority pathogen by the World Health Organization (WHO) because it causes serious and fatal disease in humans, and there are currently no effective countermeasures. Therefore, it is urgent to develop a safe and efficacious vaccine. Here, we developed six nucleotide-modified mRNA vaccines encoding different regions of the Gn and Gc proteins of RVFV encapsulated in lipid nanoparticles, compared their ability to induce immune responses in mice and found that mRNA vaccine encoding the full-length Gn and Gc proteins had the strongest ability to induce cellular and humoral immune responses. IFNAR(-/-) mice vaccinated with mRNA-GnGc were protected from lethal RVFV challenge. In addition, mRNA-GnGc induced high levels of neutralizing antibodies and cellular responses in rhesus macaques, as well as antigen-specific memory B cells. These data demonstrated that mRNA-GnGc is a potent and promising vaccine candidate for RVFV.

The advances of adjuvants in mRNA vaccines

The remarkable success of messenger RNA (mRNA) vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has propelled the rapid development of this vaccination technology in recent years. Over the last three decades, numerous studies have shown the considerable potential of mRNA vaccines that elicit protective immune responses against pathogens or cancers in preclinical studies or clinical trials. These effective mRNA vaccines usually contain specific adjuvants to obtain the desired immune effect. Vaccine adjuvants traditionally are immunopotentiators that bind to pattern recognition receptors (PRRs) of innate immune cells to increase the magnitude or achieve qualitative alteration of immune responses, finally enhancing the efficacy of vaccines. Generally, adjuvants are necessary parts of competent vaccines. According to the existing literature, adjuvants in mRNA vaccines can be broadly classified into three categories: 1) RNA with self-adjuvant characteristics, 2) components of the delivery system, and 3) exogenous immunostimulants. This review summarizes the three types of adjuvants used in mRNA vaccines and provides a comprehensive understanding of molecular mechanisms by which adjuvants exert their functions in mRNA vaccines.

In Vitro Transcribed RNA-Based Platform Vaccines: Past, Present, and Future

mRNA was discovered in 1961, but it was not used as a vaccine until after three decades. Recently, the development of mRNA vaccine technology gained great impetus from the pursuit of vaccines against COVID-19. To improve the properties of RNA vaccines, and primarily their circulation time, self-amplifying mRNA and trans-amplifying mRNA were developed. A separate branch of mRNA technology is circular RNA vaccines, which were developed with the discovery of the possibility of translation on their protein matrix. Circular RNA has several advantages over mRNA vaccines and is considered a fairly promising platform, as is trans-amplifying mRNA. This review presents an overview of the mRNA platform and a critical discussion of the more modern self-amplifying mRNA, trans-amplifying mRNA, and circular RNA platforms created on its basis. Finally, the main features, advantages, and disadvantages of each of the presented mRNA platforms are discussed. This discussion will facilitate the decision-making process in selecting the most appropriate platform for creating RNA vaccines against cancer or viral diseases.

Ionizable Lipid with Supramolecular Chemistry Features for RNA Delivery In Vivo

Lipid nanoparticles (LNPs) and ribonucleic acid (RNA) technology are highly versatile tools that can be deployed for diagnostic, prophylactic, and therapeutic applications. In this report, supramolecular chemistry concepts are incorporated into the rational design of a new ionizable lipid, C3-K2-E14, for systemic administration. This lipid incorporates a cone-shaped structure intended to facilitate cell bilayer disruption, and three tertiary amines to improve RNA binding. Additionally, hydroxyl and amide motifs are incorporated to further enhance RNA binding and improve LNP stability. Optimization of messenger RNA (mRNA) and small interfering RNA (siRNA) formulation conditions and lipid ratios produce LNPs with favorable diameter (<150 nm), polydispersity index (<0.15), and RNA encapsulation efficiency (>90%), all of which are preserved after 2 months at 4 or 37 °C storage in ready-to-use liquid form. The lipid and formulated LNPs are well-tolerated in animals and show no deleterious material-induced effects. Furthermore, 1 week after intravenous LNP administration, fluorescent signal from tagged RNA payloads are not detected. To demonstrate the long-term treatment potential for chronic diseases, repeated dosing of C3-K2-E14 LNPs containing siRNA that silences the colony stimulating factor-1 (CSF-1) gene can modulate leukocyte populations in vivo, further highlighting utility.

Understanding How Cationic Polymers' Properties Inform Toxic or Immunogenic Responses via Parametric Analysis

Cationic polymers are widely used materials in diverse biotechnologies. Subtle variations in these polymers' properties can change them from exceptional delivery agents to toxic inflammatory hazards. Conventional screening strategies optimize for function in a specific application rather than observing how underlying polymer-cell interactions emerge from polymers' properties. An alternative approach is to map basic underlying responses, such as immunogenicity or toxicity, as a function of basic physicochemical parameters to inform the design of materials for a breadth of applications. To demonstrate the potential of this approach, we synthesized 107 polymers varied in charge, hydrophobicity, and molecular weight. We then screened this library for cytotoxic behavior and immunogenic responses to map how these physicochemical properties inform polymer-cell interactions. We identify three compositional regions of interest and use confocal microscopy to uncover the mechanisms behind the observed responses. Finally, immunogenic activity is confirmed in vivo. Highly cationic polymers disrupted the cellular plasma membrane to induce a toxic phenotype, while high molecular weight, hydrophobic polymers were uptaken by active transport to induce NLRP3 inflammasome activation, an immunogenic phenotype. Tertiary amine- and triethylene glycol-containing polymers did not invoke immunogenic or toxic responses. The framework described herein allows for the systematic characterization of new cationic materials with different physicochemical properties for applications ranging from drug and gene delivery to antimicrobial coatings and tissue scaffolds.

Updated Considerations for the Immunopharmacological Aspects of the "Talented mRNA Vaccines"

Messenger RNA (mRNA) vaccines belong to a new class of medications, RNA therapeutics, including both coding and non-coding RNAs. The use of mRNA as a therapy is based on the biological role of mRNA itself, namely its translation into a functional protein. The goal of mRNA vaccines is to produce a specific antigen in cells to elicit an immune response that might be prophylactic or therapeutic. The potential of mRNA as vaccine has been envisaged for years but its efficacy has been clearly demonstrated with the approval of COVID-19 vaccines in 2021. Since then, mRNA vaccines have been in the pipeline for diseases that are still untreatable. There are many advantages of mRNA vaccines over traditional vaccines, including easy and cost-effective production, high safety, and high-level antigen expression. However, the nature of mRNA itself and some technical issues pose challenges associated with the vaccines' development and use. Here we review the immunological and pharmacological features of mRNA vaccines by discussing their pharmacokinetics, mechanisms of action, and safety, with a particular attention on the advantages and challenges related to their administration. Furthermore, we present an overview of the areas of application and the clinical trials that utilize a mRNA vaccine as a treatment.

Modeling the potential health impacts of delayed strain selection on influenza hospitalization and mortality with mRNA vaccines

Background

Influenza viruses are constantly evolving through antigenic drift, which makes vaccines potentially ill-matched to circulating strains due to the time between strain selection and distribution. mRNA technology could improve vaccine effectiveness (VE) by reducing this time. Significant private and public investments would be required to accommodate accelerated vaccine development and approval. Hence, it is important to understand the potential impact of mRNA technology on influenza hospitalizations and mortality.

Methods

We developed an age-stratified dynamic model of influenza transmission to evaluate the potential impact of increased VE (increased protection against either infection or only hospitalization) on hospitalizations and mortality in the United States. We assume that mRNA technology allows for delaying the time to strain choice, which might increase efficacy, but it does not reduce the time needed for distribution and administration, which might reduce availability. To assess this tradeoff, we evaluated two scenarios where strain choice was delayed until late summer resulting in a more effective vaccine available to (1) all age groups by October, or (2) adults 65 years and older starting in August.

Results

If not available until October, the vaccine would need a minimum of 95% effectiveness against infection to see a decrease in hospitalizations and deaths in all age groups. When delayed until November, even a 100% effective vaccine had no significant impact. For the elderly, the minimum required VE (against infection) was 50% to reduce hospitalizations and deaths. Moreover, a vaccine with 80% VE against infection available in August for the 65 + age group was better than a 95% effective vaccine available in October for all ages.

Conclusions

As the majority of influenza-associated hospitalizations and deaths are in adults 65 years and older, a combination policy targeting higher VE and coverage for this age group in the short term would be the most efficacious.

Gene-encoded nanoparticle vaccine platforms for in vivo assembly of multimeric antigen to promote adaptive immunity

Nanoparticle vaccines are a diverse category of vaccines for the prophylaxis or treatment of various diseases. Several strategies have been employed for their optimization, especially to enhance vaccine immunogenicity and generate potent B-cell responses. Two major modalities utilized for particulate antigen vaccines include using nanoscale structures for antigen delivery and nanoparticles that are themselves vaccines due to antigen display or scaffolding-the latter of which we will define as "nanovaccines." Multimeric antigen display has a variety of immunological benefits compared to monomeric vaccines mediated through potentiating antigen-presenting cell presentation and enhancing antigen-specific B-cell responses through B-cell activation. The majority of nanovaccine assembly is done in vitro using cell lines. However, in vivo assembly of scaffolded vaccines potentiated using nucleic acids or viral vectors is a burgeoning modality of nanovaccine delivery. Several advantages to in vivo assembly exist, including lower costs of production, fewer production barriers, as well as more rapid development of novel vaccine candidates for emerging diseases such as SARS-CoV-2. This review will characterize the methods for de novo assembly of nanovaccines in the host using methods of gene delivery including nucleic acid and viral vectored vaccines. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Biology-Inspired Nanomaterials > Nucleic Acid-Based Structures Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Biomedical applications of nanomaterials in the advancement of nucleic acid therapy: Mechanistic challenges, delivery strategies, and therapeutic applications

In the past few decades, substantial advancement has been made in nucleic acid (NA)-based therapies. Promising treatments include mRNA, siRNA, miRNA, and anti-sense DNA for treating various clinical disorders by modifying the expression of DNA or RNA. However, their effectiveness is limited due to their concentrated negative charge, instability, large size, and host barriers, which make widespread application difficult. The effective delivery of these medicines requires safe vectors that are efficient & selective while having non-pathogenic qualities; thus, nanomaterials have become an attractive option with promising possibilities despite some potential setbacks. Nanomaterials possess ideal characteristics, allowing them to be tuned into functional bio-entity capable of targeted delivery. In this review, current breakthroughs in the non-viral strategy of delivering NAs are discussed with the goal of overcoming challenges that would otherwise be experienced by therapeutics. It offers insight into a wide variety of existing NA-based therapeutic modalities and techniques. In addition to this, it provides a rationale for the use of non-viral vectors and a variety of nanomaterials to accomplish efficient gene therapy. Further, it discusses the potential for biomedical application of nanomaterials-based gene therapy in various conditions, such as cancer therapy, tissue engineering, neurological disorders, and infections.

Advances in saRNA Vaccine Research against Emerging/Re-Emerging Viruses

Although conventional vaccine approaches have proven to be successful in preventing infectious diseases in past decades, for vaccine development against emerging/re-emerging viruses, one of the main challenges is rapid response in terms of design and manufacture. mRNA vaccines can be designed and produced within days, representing a powerful approach for developing vaccines. Furthermore, mRNA vaccines can be scaled up and may not have the risk of integration. mRNA vaccines are roughly divided into non-replicating mRNA vaccines and self-amplifying RNA (saRNA) vaccines. In this review, we provide an overview of saRNA vaccines, and discuss future directions and challenges in advancing this promising vaccine platform to combat emerging/re-emerging viruses.

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.

Metallic Nanoparticles and Core-Shell Nanosystems in the Treatment, Diagnosis, and Prevention of Parasitic Diseases

The usage of nanotechnology in the fight against parasitic diseases is in the early stages of development, but it brings hopes that this new field will provide a solution to target the early stages of parasitosis, compensate for the lack of vaccines for most parasitic diseases, and also provide new treatment options for diseases in which parasites show increased resistance to current drugs. The huge physicochemical diversity of nanomaterials developed so far, mainly for antibacterial and anti-cancer therapies, requires additional studies to determine their antiparasitic potential. When designing metallic nanoparticles (MeNPs) and specific nanosystems, such as complexes of MeNPs, with the shell of attached drugs, several physicochemical properties need to be considered. The most important are: size, shape, surface charge, type of surfactants that control their dispersion, and shell molecules that should assure specific molecular interaction with targeted molecules of parasites' cells. Therefore, it can be expected that the development of antiparasitic drugs using strategies provided by nanotechnology and the use of nanomaterials for diagnostic purposes will soon provide new and effective methods of antiparasitic therapy and effective diagnostic tools that will improve the prevention and reduce the morbidity and mortality caused by these diseases.

Cargo-selective and adaptive delivery of nucleic acid therapeutics by bola-amphiphilic dendrimers

Nucleic acid therapeutics are becoming an important drug modality, offering the unique opportunity to address "undruggable" targets, respond rapidly to evolving pathogens, and treat diseases at the gene level for precision medicine. However, nucleic acid therapeutics have poor bioavailability and are chemolabile and enzymolabile, imposing the need for delivery vectors. Dendrimers, by virtue of their well-defined structure and cooperative multivalence, represent precision delivery systems. We synthesized and studied bola-amphiphilic dendrimers for cargo-selective and on-demand delivery of DNA and small interfering RNA (siRNA), both important nucleic acid therapeutics. Remarkably, superior performances were achieved for siRNA delivery with the second-generation dendrimer, yet for DNA delivery with the third generation. We systematically studied these dendrimers with regard to cargo binding, cellular uptake, endosomal release, and in vivo delivery. Differences in size both of the dendrimers and their nucleic acid cargos impacted the cooperative multivalent interactions for cargo binding and release, leading to cargo-adaptive and selective delivery. Moreover, both dendrimers harnessed the advantages of lipid and polymer vectors, while offering nanotechnology-based tumor targeting and redox-responsive cargo release. Notably, they allowed tumor- and cancer cell-specific delivery of siRNA and DNA therapeutics for effective treatment in different cancer models, including aggressive and metastatic malignancies, outperforming the currently available vectors. This study provides avenues to engineer tailor-made vectors for nucleic acid delivery and precision medicine.

Biodegradable Polyester Nanoparticle Vaccines Deliver Self-Amplifying mRNA in Mice at Low Doses

Delivery of self-amplifying mRNA (SAM) has high potential for infectious disease vaccination due its self-adjuvating and dose-sparing properties. Yet a challenge is the susceptibility of SAM to degradation and the need for SAM to reach the cytosol fully intact to enable self-amplification. Lipid nanoparticles have been successfully deployed at incredible speed for mRNA vaccination, but aspects such as cold storage, manufacturing, efficiency of delivery, and the therapeutic window would benefit from further improvement. To investigate alternatives to lipid nanoparticles, we developed a class of >200 biodegradable end-capped lipophilic poly(beta-amino ester)s (PBAEs) that enable efficient delivery of SAM in vitro and in vivo as assessed by measuring expression of SAM encoding reporter proteins. We evaluated the ability of these polymers to deliver SAM intramuscularly in mice, and identified a polymer-based formulation that yielded up to 37-fold higher intramuscular (IM) expression of SAM compared to injected naked SAM. Using the same nanoparticle formulation to deliver a SAM encoding rabies virus glycoprotein, the vaccine elicited superior immunogenicity compared to naked SAM delivery, leading to seroconversion in mice at low RNA injection doses. These biodegradable nanomaterials may be useful in the development of next-generation RNA vaccines for infectious diseases.

Cholesterol-Amino-Phosphate (CAP) Derived Lipid Nanoparticles for Delivery of Self-Amplifying RNA and Restoration of Spermatogenesis in Infertile Mice

Male infertility caused by genetic mutations is an important type of infertility. Currently, there is no reliable method in the clinic to address this medical need. The emergence of mRNA therapy provides a possible strategy for restoring mutant genes in the reproductive system. However, effective delivery of mRNA to spermatocytes remains a formidable challenge. Here a series of cholesterol-amino-phosphate (CAP) lipids are reported by integrating three bioactive moieties into a geometric structure, which is favorable for mRNA delivery. The results demonstrate that CAP-derived lipid nanoparticles (CAP LNPs) can deliver RNA including traditional mRNA and self-amplifying RNA (saRNA) encoding DNA Meiotic Recombinase 1 (Dmc1) protein in spermatocytes and treat male infertility caused by the Dmc1 gene mutation. Notably, the delivery efficiency of CAP LNPs is significantly higher than that of the MC3 and ALC-0315 LNPs, which is consistent with the design of CAP molecules. More importantly, a single injection of CAP LNPs-saRNA can produce Dmc1 protein for an extended period, which restores the spermatogenesis in the Dmc1 gene knockout mouse model. Overall, this study proves the concept of LNPs for the delivery of mRNA to spermatocytes, which provides a unique method to probe male infertility caused by the genetic mutation.

Dendrimer-Mediated Delivery of DNA and RNA Vaccines

DNA and RNA vaccines (nucleic acid-based vaccines) are a promising platform for vaccine development. The first mRNA vaccines (Moderna and Pfizer/BioNTech) were approved in 2020, and a DNA vaccine (Zydus Cadila, India), in 2021. They display unique benefits in the current COVID-19 pandemic. Nucleic acid-based vaccines have a number of advantages, such as safety, efficacy, and low cost. They are potentially faster to develop, cheaper to produce, and easier to store and transport. A crucial step in the technology of DNA or RNA vaccines is choosing an efficient delivery method. Nucleic acid delivery using liposomes is the most popular approach today, but this method has certain disadvantages. Therefore, studies are actively underway to develop various alternative delivery methods, among which synthetic cationic polymers such as dendrimers are very attractive. Dendrimers are three-dimensional nanostructures with a high degree of molecular homogeneity, adjustable size, multivalence, high surface functionality, and high aqueous solubility. The biosafety of some dendrimers has been evaluated in several clinical trials presented in this review. Due to these important and attractive properties, dendrimers are already being used to deliver a number of drugs and are being explored as promising carriers for nucleic acid-based vaccines. This review summarizes the literature data on the development of dendrimer-based delivery systems for DNA and mRNA vaccines.

Nanoparticles as a Delivery System of Antigens for the Development of an Effective Vaccine against Toxoplasma gondii

Nanoparticles include particles ranging in size from nanometers to micrometers, whose physicochemical characteristics are optimized to make them appropriate delivery vehicles for drugs or immunogens important in the fight and/or prevention of infectious diseases. There has been a rise in the use of nanoparticles in preventive vaccine formulations as immunostimulatory adjuvants, and as vehicles for immunogen delivery to target immune cells. Toxoplasma is important worldwide, and may cause human toxoplasmosis. In immunocompetent hosts, infection is usually asymptomatic, but in immunocompromised patients it can cause serious neurological and ocular consequences, such as encephalitis and retinochoroiditis. Primary infection during pregnancy may cause abortion or congenital toxoplasmosis. Currently, there is no effective human vaccine against this disease. Evidence has emerged from several experimental studies testing nanovaccines showing them to be promising tools in the prevention of experimental toxoplasmosis. For the present study, a literature review was carried out on articles published over the last 10 years through the PubMed database, pertaining to in vivo experimental models of T. gondii infection where nanovaccines were tested and protection and immune responses evaluated. This review aims to highlight the way forward in the search for an effective vaccine for toxoplasmosis.

The mRNA Vaccine Technology Era and the Future Control of Parasitic Infections

Despite intensive long-term efforts, with very few exceptions, the development of effective vaccines against parasitic infections has presented considerable challenges, given the complexity of parasite life cycles, the interplay between parasites and their hosts, and their capacity to escape the host immune system and to regulate host immune responses. For many parasitic diseases, conventional vaccine platforms have generally proven ill suited, considering the complex manufacturing processes involved and the costs they incur, the inability to posttranslationally modify cloned target antigens, and the absence of long-lasting protective immunity induced by these antigens. An effective antiparasite vaccine platform is required to assess the effectiveness of novel vaccine candidates at high throughput. By exploiting the approach that has recently been used successfully to produce highly protective COVID mRNA vaccines, we anticipate a new wave of research to advance the use of mRNA vaccines to prevent parasitic infections in the near future. This article considers the characteristics that are required to develop a potent antiparasite vaccine and provides a conceptual foundation to promote the development of parasite mRNA-based vaccines. We review the recent advances and challenges encountered in developing antiparasite vaccines and evaluate the potential of developing mRNA vaccines against parasites, including those causing diseases such as malaria and schistosomiasis, against which vaccines are currently suboptimal or not yet available.

Precise and systematic end group chemistry modifications on PAMAM and poly(l-lysine) dendrimers to improve cytosolic delivery of mRNA

Here, we aimed to chemically modify PAMAM dendrimers using lysine as a site-selective anchor for successfully delivering mRNA while maintaining a low toxicity profile. PAMAM dendrimers were multi-functionalised by amidation reactions in a regioselective, quantitative and stepwise manner with carefully selected property-modifying surface groups. Alternatively, novel lysine-based dendrimers were prepared in the same manner with the aim to unlock their potential in gene delivery. The modified dendrimers were then formulated with Cy5-EGFP mRNA by bulk mixing via liquid handling robotics across different nitrogen to phosphate ratios. The resulting dendriplexes were characterised by size, charge, mRNA encapsulation, and mRNA binding affinity. Finally, their in-vitro delivery activity was systematically investigated across key cellular trafficking stages to relate chemical design to cellular effect. We demonstrate our findings in different cell lines and benchmarked relative to a commercially available transfection agent, jetPEI®. We demonstrate that specific surface modifications are required to generate small, reliable and well-encapsulated positively charged dendriplex complexes. Furthermore, we show that introduction of fusogenic groups is essential for driving endosomal escape and achieving cellular delivery and translation of mRNA in these cell lines.

Development and applications of mRNA treatment based on lipid nanoparticles

Nucleic acid-based therapies such as messenger RNA have the potential to revolutionize modern medicine and enhance the performance of existing pharmaceuticals. The key challenges of mRNA-based therapies are delivering the mRNA safely and effectively to the target tissues and cells and controlling its release from the delivery vehicle. Lipid nanoparticles (LNPs) have been widely studied as drug carriers and are considered to be state-of-the-art technology for nucleic acid delivery. In this review, we begin by presenting the advantages and mechanisms of action of mRNA therapeutics. Then we discuss the design of LNP platforms based on ionizable lipids and the applications of mRNA-LNP vaccines for prevention of infectious diseases and for treatment of cancer and various genetic diseases. Finally, we describe the challenges and future prospects of mRNA-LNP therapeutics.

Optimal delivery strategies for nanoparticle-mediated mRNA delivery

Messenger RNA (mRNA) has emerged as a new and efficient agent for the treatment of various diseases. The success of lipid nanoparticle-mRNA against the novel coronavirus (SARS-CoV-2) pneumonia epidemic has proved the clinical potential of nanoparticle-mRNA formulations. However, the deficiency in the effective biological distribution, high transfection efficiency and good biosafety are still the major challenges in clinical translation of nanomedicine for mRNA delivery. To date, a variety of promising nanoparticles have been constructed and then gradually optimized to facilitate the effective biodistribution of carriers and efficient mRNA delivery. In this review, we describe the design of nanoparticles with an emphasis on lipid nanoparticles, and discuss the manipulation strategies for nanoparticle-biology (nano-bio) interactions for mRNA delivery to overcome the biological barriers and improve the delivery efficiency, because the specific nano-bio interaction of nanoparticles usually remoulds the biomedical and physiological properties of the nanoparticles especially the biodistribution, mechanism of cellular internalization and immune response. Finally, we give a perspective for the future applications of this promising technology. We believe that the regulation of nano-bio interactions would be a significant breakthrough to improve the mRNA delivery efficiency and cross biological barriers. This review may provide a new direction for the design of nanoparticle-mediated mRNA delivery systems.

Immunogenicity and protective efficacy of an inactivated Newcastle disease virus vaccine encapsulated in poly-(lactic-co-glycolic acid) nanoparticles

An immunization experiment was conducted in specific pathogen-free chickens with the inactivated Newcastle disease virus (NDV) vaccine encapsulated in the poly-(lactic-co-glycolic) acid (PLGA) nanoparticles (NP) to evaluate its immunogenicity and protective efficacy. The NDV vaccine was prepared by inactivating one virulent Indian strain of NDV belonging to Genotype VII by using beta-propiolactone. PLGA nanoparticles encapsulating inactivated NDV were prepared by the solvent evaporation method. Scanning electron microscopy and zeta sizer analysis revealed that the (PLGA+NDV) NP were spherical, with an average size of 300 nm, having a zeta potential of -6 mV. The encapsulation efficiency and loading efficiency were 72% and 2.4%, respectively. On immunization trial in chicken, the (PLGA+NDV) NP induced significantly (P < 0.0001) higher levels of HI and IgY antibodies with the peak HI titer of 2⁸ and higher expression of IL-4 mRNA. The consistency of higher antibody levels suggests slow and pulsatile release of the antigens from the (PLGA+NDV) NP. The nano-NDV vaccine also induced cell mediated immunity with higher expression of IFN-γ indicating strong Th1 mediated immune responses in contrast to the commercial oil adjuvanted inactivated NDV vaccine. Further, the (PLGA+NDV) NP afforded 100% protection against the virulent NDV challenge. Our results suggested that PLGA NP have adjuvant potential on induction of humoral as well as Th1 biased cell mediated immune responses and also enhanced protective efficacy of the inactivated NDV vaccine. This study provides an insight for development of PLGA NP based inactivated NDV vaccine using the same genotype circulating in the field as well as for other avian diseases at exigencies.

Immunomodulatory nanosystems: An emerging strategy to combat viral infections

The viral infection spreads with the assistance of a host. Traditional antiviral therapies cannot provide long-term immunity against emerging and drug-resistant viral infections. Immunotherapy has evolved as an efficient approach for disease prevention and treatment, which include cancer, infections, inflammatory, and immune disorders. Immunomodulatory nanosystems can dramatically enhance therapeutic outcomes by combating many therapeutic challenges, such as poor immune stimulation and off-target adverse effects. Recently, immunomodulatory nanosystems have emerged as a potent antiviral strategy to intercept viral infections effectively. This review introduces major viral infections with their primary symptoms, route of transmission & targeted organ, and different stages of the viral life cycle with respective traditional blockers. The IMNs have an exceptional capacity for precisely modulating the immune system for therapeutic applications. The nano sized immunomodulatory systems permit the immune cells to interact with infectious agents enhancing lymphatic drainage and endocytosis by the over-reactive immune cells in the infected areas. Immune cells that can be modulated upon viral infection via various immunomodulatory nanosystems have been discussed. Advancement in theranostics can yield an accurate diagnosis, adequate treatment, and real-time screening of viral infections. Nanosystem-based drug delivery can continue to thrive in diagnosing, treating, and preventing viral infections. The curative medicine for remerging and drug-resistant viruses remains challenging, though certain systems have expanded our perception and initiated a new research domain in antiviral treatments.

Polymer-Based mRNA Delivery Strategies for Advanced Therapies

Messenger RNA (mRNA)-based therapies offer great promise for the treatment of a variety of diseases. In 2020, two FDA approvals of mRNA-based vaccines have elevated mRNA vaccines to global recognition. However, the therapeutic capabilities of mRNA extend far beyond vaccines against infectious diseases. They hold potential for cancer vaccines, protein replacement therapies, gene editing therapies, and immunotherapies. For realizing such advanced therapies, it is crucial to develop effective carrier systems. Recent advances in materials science have led to the development of promising nonviral mRNA delivery systems. In comparison to other carriers like lipid nanoparticles, polymer-based delivery systems often receive less attention, despite their unique ability to carefully tune their chemical features to promote mRNA protection, their favorable pharmacokinetics, and their potential for targeting delivery. In this review, the central features of polymer-based systems for mRNA delivery highlighting the molecular design criteria, stability, and biodistribution are discussed. Finally, the role of targeting ligands for the future of RNA therapies is analyzed.

High-Precision Synthesis of RNA-Loaded Lipid Nanoparticles for Biomedical Applications

The recent development of RNA-based therapeutics in delivering nucleic acids for gene editing and regulating protein translation has led to the effective treatment of various diseases including cancer, inflammatory and genetic disorder, as well as infectious diseases. Among these, lipid nanoparticles (LNP) have emerged as a promising platform for RNA delivery and have shed light by resolving the inherent instability issues of naked RNA and thereby enhancing the therapeutic potency. These LNP consisting of ionizable lipid, helper lipid, cholesterol, and poly(ethylene glycol)-anchored lipid can stably enclose RNA and help them release into the cells' cytosol. Herein, the significant progress made in LNP research starting from the LNP constituents, formulation, and their diverse applications is summarized first. Moreover, the microfluidic methodologies which allow precise assembly of these newly developed constituents to achieve LNP with controllable composition and size, high encapsulation efficiency as well as scalable production are highlighted. Furthermore, a short discussion on current challenges as well as an outlook will be given on emerging approaches to resolving these issues.

Iterative Design of Ionizable Lipids for Intramuscular mRNA Delivery

Lipid nanoparticles (LNPs) are the most clinically advanced delivery vehicles for RNA and have enabled the development of RNA-based drugs such as the mRNA COVID-19 vaccines. Functional delivery of mRNA by an LNP greatly depends on the inclusion of an ionizable lipid, and small changes to these lipid structures can significantly improve delivery. However, the structure-function relationships between ionizable lipids and mRNA delivery are poorly understood, especially for LNPs administered intramuscularly. Here, we show that the iterative design of a novel series of ionizable lipids generates key structure-activity relationships and enables the optimization of chemically distinct lipids with efficacy that is on-par with the current state of the art. We find that the combination of ionizable lipids comprising an ethanolamine core and LNPs with an apparent pK_a between 6.6 and 6.9 maximizes intramuscular mRNA delivery. Furthermore, we report a nonlinear relationship between the lipid-to-mRNA mass ratio and protein expression, suggesting that a critical mass ratio exists for LNPs and may depend on ionizable lipid structure. Our findings add to the mechanistic understanding of ionizable lipids and demonstrate that hydrogen bonding, ionization behavior, and lipid-to-mRNA mass ratio are key design parameters affecting intramuscular mRNA delivery. We validate these insights by applying them to the rational design of new ionizable lipids. Overall, our iterative design strategy efficiently generates potent ionizable lipids. This hypothesis-driven method reveals structure-activity relationships that lay the foundation for the optimization of ionizable lipids in future LNP-RNA drugs. We foresee that this design strategy can be extended to other optimization parameters beyond intramuscular expression.

Self-amplifying RNA vaccine protects mice against lethal Ebola virus infection

Emerging and re-emerging viruses, such as Zaire Ebola virus (EBOV), pose a global threat and require immediate countermeasures, including the rapid development of effective vaccines that are easy to manufacture. Synthetic self-amplifying RNAs (saRNAs) attend to these needs, being safe and strong immune stimulators that can be inexpensively produced in large quantities, using cell-free systems and good manufacturing practice. Here, the first goal was to develop and optimize an anti-EBOV saRNA-based vaccine in terms of its antigen composition and route of administration. Vaccinating mice with saRNAs expressing the EBOV glycoprotein (GP) alone or in combination with the nucleoprotein (NP) elicited antigen-specific immune responses. GP-specific antibodies showed neutralizing activity against EBOV. Strong CD4+ T cell response against NP and GP and CD8+ T cell response against NP were detected by ELISpot assays. Intramuscular vaccination with saRNAs conferred better immune response than intradermal. Finally, mice vaccinated in a prime-boost regimen with saRNAs encoding both GP and NP or with GP alone survived an EBOV infection. In addition, a single dose of GP and NP saRNAs was also protective against fatal EBOV infection. Overall, saRNAs expressing viral antigens represent a promising vaccine platform.

Advanced implications of nanotechnology in disease control and environmental perspectives

Nanotechnology encompasses a wide range of devices derived from biology, engineering, chemistry, and physics, and this scientific field is composed of great collaboration among researchers from several fields. It has diverse implications notably smart sensing technologies, effective disease diagnosis, and sometimes used in treatment. In medical science, the implications of nanotechnology include the development of elements and devices that interact with the body at subcellular (i.e., molecular) levels exhibiting high sensitivity and specificity. There is a plethora of new chances for medical science and disease treatment to be discovered and exploited in the rapidly developing field of nanotechnology. In different sectors, nanomaterials are used just because of their special characteristics. Their large surface area of them enables higher reactivity with greater efficiency. Furthermore, special surface chemistry is displayed by nanomaterials which compare to conventional materials and facilitate the nanomaterials to decrease pollutants efficiently. Recently, nanomaterials are used in some countries to reduce the levels of contaminants in water, air, and soil. Moreover, nanomaterials are used in the cosmetics and medical industry, and it develops the drug discovery (DD) system. Among a huge number of nanomaterials, Cu, Ag, TiO₂, ZnO, Fe₃O₄, and carbon nanotubes (CNTs) are extensively used in different industries for various purposes. This extensive review study has introduced the major scientific and technical features of nanotechnology, as well as some possible clinical applications and positive feedback in environmental waste management and drug delivery systems.

A Comprehensive Review of mRNA Vaccines

mRNA vaccines have been demonstrated as a powerful alternative to traditional conventional vaccines because of their high potency, safety and efficacy, capacity for rapid clinical development, and potential for rapid, low-cost manufacturing. These vaccines have progressed from being a mere curiosity to emerging as COVID-19 pandemic vaccine front-runners. The advancements in the field of nanotechnology for developing delivery vehicles for mRNA vaccines are highly significant. In this review we have summarized each and every aspect of the mRNA vaccine. The article describes the mRNA structure, its pharmacological function of immunity induction, lipid nanoparticles (LNPs), and the upstream, downstream, and formulation process of mRNA vaccine manufacturing. Additionally, mRNA vaccines in clinical trials are also described. A deep dive into the future perspectives of mRNA vaccines, such as its freeze-drying, delivery systems, and LNPs targeting antigen-presenting cells and dendritic cells, are also summarized.

mRNA-From COVID-19 Treatment to Cancer Immunotherapy

This review provides an overview covering mRNA from its use in the COVID-19 pandemic to cancer immunotherapy, starting from the selection of appropriate antigens, tumor-associated and tumor-specific antigens, neoantigens, the basics of optimizing the mRNA molecule in terms of stability, efficacy, and tolerability, choosing the best formulation and the optimal route of administration, to summarizing current clinical trials of mRNA vaccines in tumor therapy.

From design to clinic: Engineered peptide nanomaterials for cancer immunotherapy

Immunotherapy has revolutionized the field of cancer therapy. Nanomaterials can further improve the efficacy and safety of immunotherapy because of their tunability and multifunctionality. Owing to their natural biocompatibility, diverse designs, and dynamic self-assembly, peptide-based nanomaterials hold great potential as immunotherapeutic agents for many malignant cancers, with good immune response and safety. Over the past several decades, peptides have been developed as tumor antigens, effective antigen delivery carriers, and self-assembling adjuvants for cancer immunotherapy. In this review, we give a brief introduction to the use of peptide-based nanomaterials for cancer immunotherapy as antigens, carriers, and adjuvants, and to their current clinical applications. Overall, this review can facilitate further understanding of peptide-based nanomaterials for cancer immunotherapy and may pave the way for designing safe and efficient methods for future vaccines or immunotherapies.

Bioresponsive Immunotherapeutic Materials

The human immune system is an interaction network of biological processes, and its dysfunction is closely associated with a wide array of diseases, such as cancer, infectious diseases, tissue damage, and autoimmune diseases. Manipulation of the immune response network in a desired and controlled fashion has been regarded as a promising strategy for maximizing immunotherapeutic efficacy and minimizing side effects. Integration of "smart" bioresponsive materials with immunoactive agents including small molecules, biomacromolecules, and cells can achieve on-demand release of agents at targeted sites to reduce overdose-related toxicity and alleviate off-target effects. This review highlights the design principles of bioresponsive immunotherapeutic materials and discusses the critical roles of controlled release of immunoactive agents from bioresponsive materials in recruiting, housing, and manipulating immune cells for evoking desired immune responses. Challenges and future directions from the perspective of clinical translation are also discussed.