Transdermal Immunization of Elastic Liposome-Laden Recombinant Chimeric Fusion Protein of P. falciparum (PfMSP-Fu24) Mounts Protective Immune Response

Protocol for oleuropein-induced autophagy mediating drug tolerance in P. falciparum

The anti-inflammatory activity of a phytocompound (oleuropein [OLP]) in the lipopolysaccharide (LPS)-mimicked macrophage model of inflammation demonstrates the importance of PI3K-Akt1 signaling in establishing "immune homeostasis." Here, we present a protocol for the cultivation of in vitro cultures of P. falciparum for carrying out drug sensitivity assays. We describe steps for parasite synchronization, drug treatment, DNA isolation, and starvation-induced autophagy. This protocol provides insights into autophagy and parasite tolerance to drug pressure. For complete details on the use and execution of this protocol, please refer to Sharma et al.1.

Biogenically synthesized green silver nanoparticles exhibit antimalarial activity

The suboptimal efficacies of existing anti-malarial drugs attributed to the emergence of drug resistance dampen the clinical outcomes. Hence, there is a need for developing novel drug and drug targets. Recently silver nanoparticles (AgNPs) constructed with the leaf extracts of Euphorbia cotinifolia were shown to possess antimalarial activity. Therefore, the synthesized AgNPs from Euphorbia cotinifolia (EcAgNPs) were tested for their parasite clearance activity. We determined the antimalarial activity in the asexual blood stage infection of 3D7 (laboratory strain) P. falciparum. EcAgNPs demonstrated the significant inhibition of parasite growth (EC50 of 0.75 µg/ml) in the routine in vitro culture of P. falciparum. The synthesized silver nanoparticles were seen to induce apoptosis in P. falciparum through increased reactive oxygen species (ROS) ROS production and activated programmed cell death pathways characterized by the caspase-3 and calpain activity. Also, altered transcriptional regulation of Bax/Bcl-2 ratio indicated the enhanced apoptosis. Moreover, inhibited expression of PfLPL-1 by EcAgNPs is suggestive of the dysregulated host fatty acid flux via parasite lipid storage. Overall, our findings suggest that EcAgNPs are a non-toxic and targeted antimalarial treatment, and could be a promising therapeutic approach for clearing malaria infection.

Adjuvants in cutaneous vaccination: A comprehensive analysis

Skin is the body's largest organ and serves as a protective barrier from physical, thermal, and mechanical environmental challenges. Alongside, the skin hosts key immune system players, such as the professional antigen-presenting cells (APCs) like the Langerhans cells in the epidermis and circulating macrophages in the blood. Further, the literature supports that the APCs can be activated by antigen or vaccine delivery via multiple routes of administration through the skin. Once activated, the stimulated APCs drain to the associated lymph nodes and gain access to the lymphatic system. This further allows the APCs to engage with the adaptive immune system and activate cellular and humoral immune responses. Thus, vaccine delivery via skin offers advantages such as reliable antigen delivery, superior immunogenicity, and convenient delivery. Several preclinical and clinical studies have demonstrated the significance of vaccine delivery using various routes of administration via skin. However, such vaccines often employ adjuvant/(s), along with the antigen of interest. Adjuvants augment the immune response to a vaccine antigen and improve the therapeutic efficacy. Due to these reasons, adjuvants have been successfully used with infectious disease vaccines, cancer immunotherapy, and immune-mediated diseases. To capture these developments, this review will summarize preclinical and clinical study results of vaccine delivery via skin in the presence of adjuvants. A focused discussion regarding the FDA-approved adjuvants will address the experiences of using such adjuvant-containing vaccines. In addition, the challenges and regulatory concerns with these adjuvants will be discussed. Finally, the review will share the prospects of adjuvant-containing vaccines delivered via skin.

Pseudovirus Nanoparticles Displaying Plasmodium Circumsporozoite Proteins Elicited High Titers of Sporozoite-Binding Antibody

BACKGROUND

malaria caused by Plasmodium parasites remains a public health threat. The circumsporozoite proteins (CSPs) of Plasmodium sporozoite play a key role in Plasmodium infection, serving as an excellent vaccine target.

METHODS

using a self-assembled S60 nanoparticle platform, we generated pseudovirus nanoparticles (PVNPs) displaying CSPs, named S-CSPs, for enhanced immunogenicity.

RESULTS

purified Hisx6-tagged or tag-free S-CSPs self-assembled into PVNPs that consist of a norovirus S60 inner shell and multiple surface-displayed CSPs. The majority of the PVNPs measured ~27 nm with some size variations, and their three-dimensional structure was modeled. The PVNP-displayed CSPs retained their glycan receptor-binding function. A mouse immunization study showed that PVNPs induced a high antibody response against CSP antigens and the PVNP-immunized mouse sera stained the CSPs of Plasmodium sporozoites at high titer.

CONCLUSIONS AND DISCUSSION

the PVNP-displayed CSPs retain their authentic antigenic feature and receptor-binding function. The CSP-specific antibody elicited by the S-CSP PVNPs binds original CSPs and potentially inhibits the attachment of Plasmodium sporozoites to their host cells, a key step for liver invasion by the sporozoites. Thus, S-CSP PVNPs may be an excellent vaccine candidate against malaria caused by Plasmodium parasites.

Immunogenic characterization of AlPO4 adsorbed Td vaccine and liposome-mediated Td vaccine

Purpose

The purpose of this study was to compare the antigenic potency and stability of tetanus and diphtheria (Td) vaccines when combined with aluminum phosphate (AlPO4) and liposome adjuvants.

Materials and Methods

In vitro and in vivo analyses were conducted using the single radial immunodiffusion method and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The Td vaccines were prepared with AlPO4 adsorption and liposome-mediated delivery, and protein antigens were characterized using these methods.

Results

The results revealed that the liposome-mediated Td vaccines exhibited higher immunogenicity compared to the AlPO4-adsorbed Td vaccines. Additionally, the liposome-mediated Td vaccines demonstrated higher stability as native antigens.

Conclusion

This study highlights the importance of utilizing liposome adjuvants in vaccine development. The liposome-mediated Td vaccines showed enhanced immunogenicity and stability, making them a promising approach for improving vaccine efficacy. Understanding and optimizing adjuvant strategies can contribute to the development of effective vaccines against various diseases.

Aceclofenac and methotrexate combination therapy could influence Th1/Th17 axis to modulate rheumatoid-arthritis-induced inflammation

Rheumatoid arthritis (RA) is an inflammatory, autoimmune and connective-tissue arthropathy. The methotrexate (MTX) and aceclofenac (ACL) combination drug regimen is known to regulate the immunological pathways. Also, RA-elicited inflammation is decreased by the combination drug treatment. ACL and MTX combination treatment has been shown to regulate the signaling pathway controlled by NF-κB and FOXO1. The present manuscript reviews the importance of the combination drug regimen to treat and/or manage RA. The combination drug regimen could affect the Th1/Th17 axis to switch the balance toward the immunoregulatory (Th1) phenotype for establishing immune homeostasis. In conclusion, we propose the study of the immunological signaling pathways in experimental humanized RA mice.

Mannose-modified erythrocyte membrane-encapsulated chitovanic nanoparticles as a DNA vaccine carrier against reticuloendothelial tissue hyperplasia virus

Introduction

The erythrocyte membranes used in nanovaccines include high membrane stability, long circulation life, adaptability and extremely good bio compatibility. Nanoparticles encapsulated by erythrocyte membranes are widely used as ideal drug delivery vehicles because of their high drug loading, long circulation time, and excellent biocompatibility. The mannose modification of delivery materials can help target mannose receptors (MRs) to deliver antigens to antigen-presenting cells (APCs).

Methods

In this study, the antigen gene gp90 of avian reticuloendotheliosis virus (REV) was encapsulated with carboxymethyl chitosan (CS) to obtain CSgp90 nanoparticles, which were coated with mannose-modied fowl erythrocyte membranes to yield CS-gp90@M-M nanoparticles. The physicochemical characterization and immune response of the CS-gp90@M-M nanoparticles were investigated in vitro and in vivo.

Results

CS-gp90@M-M nanoparticles were rapidly phagocytized in vitro by macrophages to induce the production of cytokines and nitric oxide. In vivo, CS-gp90@M-M nanoparticles increased cytokine levels, the CD4+/8+ ratio, REV-specific antibodies in the peripheral blood of chicks, and the mRNA levels of immune-related genes in the spleen and bursa of immunized chicks. CS-gp90@M-M nanoparticles could be targeted to lymphoid organs to prolong the retention time of the nanoparticles at the injection site and lymphatic organs, leading to a strong, sustained immune response. Moreover, the CS-gp90@M-M nano-vaccine showed a lasting immunoprotective effect and improved the body weight of chicks after the challenge.

Conclusion

Overall, CS-gp90@M-M nanoparticles can be used in vaccine designs as an effective delivery carrier with immune response-enhancing effects.

Novel Pharmaceutical Strategies for Enhancing Skin Penetration of Biomacromolecules

Skin delivery of biomacromolecules holds great advantages in the systemic and local treatment of multiple diseases. However, the densely packed stratum corneum and the tight junctions between keratinocytes stand as formidable skin barriers against the penetration of most drug molecules. The large molecular weight, high hydrophilicity, and lability nature of biomacromolecules pose further challenges to their skin penetration. Recently, novel penetration enhancers, nano vesicles, and microneedles have emerged as efficient strategies to deliver biomacromolecules deep into the skin to exert their therapeutic action. This paper reviews the potential application and mechanisms of novel skin delivery strategies with emphasis on the pharmaceutical formulations.

Nanocarrier-Based Approaches for the Efficient Delivery of Anti-Tubercular Drugs and Vaccines for Management of Tuberculosis

Drug-resistant species of tuberculosis (TB), which spread faster than traditiona TB, is a severely infectious disease. The conventional drug therapy used in the management of tuberculosis has several challenges linked with adverse effects. Hence, nanotherapeutics served as an emerging technique to overcome problems associated with current treatment. Nanotherapeutics helps to overcome toxicity and poor solubility issues of several drugs used in the management of tuberculosis. Due to their diameter and surface chemistry, nanocarriers encapsulated with antimicrobial drugs are readily taken up by macrophages. Macrophages play a crucial role as they serve as target sites for active and passive targeting for nanocarriers. The surface of the nanocarriers is coated with ligand-specific receptors, which further enhances drug concentration locally and indicates the therapeutic potential of nanocarriers. This review highlights tuberculosis's current facts, figures, challenges associated with conventional treatment, different nanocarrier-based systems, and its application in vaccine development.

From influenza to COVID-19: Lipid nanoparticle mRNA vaccines at the frontiers of infectious diseases

Vaccination represents the best line of defense against infectious diseases and is crucial in curtailing pandemic spread of emerging pathogens to which a population has limited immunity. In recent years, mRNA vaccines have been proposed as the new frontier in vaccination, owing to their facile and rapid development while providing a safer alternative to traditional vaccine technologies such as live or attenuated viruses. Recent breakthroughs in mRNA vaccination have been through formulation with lipid nanoparticles (LNPs), which provide both protection and enhanced delivery of mRNA vaccines in vivo. In this review, current paradigms and state-of-the-art in mRNA-LNP vaccine development are explored through first highlighting advantages posed by mRNA vaccines, establishing LNPs as a biocompatible delivery system, and finally exploring the use of mRNA-LNP vaccines in vivo against infectious disease towards translation to the clinic. Furthermore, we highlight the progress of mRNA-LNP vaccine candidates against COVID-19 currently in clinical trials, with the current status and approval timelines, before discussing their future outlook and challenges that need to be overcome towards establishing mRNA-LNPs as next-generation vaccines. STATEMENT OF SIGNIFICANCE: With the recent success of mRNA vaccines developed by Moderna and BioNTech/Pfizer against COVID-19, mRNA technology and lipid nanoparticles (LNP) have never received more attention. This manuscript timely reviews the most advanced mRNA-LNP vaccines that have just been approved for emergency use and are in clinical trials, with a focus on the remarkable development of several COVID-19 vaccines, faster than any other vaccine in history. We aim to give a comprehensive introduction of mRNA and LNP technology to the field of biomaterials science and increase accessibility to readers with a new interest in mRNA-LNP vaccines. We also highlight current limitations and future outlook of the mRNA vaccine technology that need further efforts of biomaterials scientists to address.

Nanostructured Lipid Carrier-Mediated Transdermal Delivery of Aceclofenac Hydrogel Present an Effective Therapeutic Approach for Inflammatory Diseases

Aceclofenac (ACE), a cyclooxygenase-2 inhibitor, is the derivative of the diclofenac group that has been in use for the symptomatic treatment of systemic inflammatory autoimmune disease, rheumatoid arthritis (RA). Partial solubility, high lipophilic nature, and stability challenge its use in developing topical formulations. Hence, we developed and characterized nanostructured lipid carrier (NLC)-based ACE (ACE-NLC) hydrogel for an efficient transdermal delivery. NLC microemulsion was prepared using different lipids by various methods and was characterized with respect to particle size, zeta potential, surface morphology, and drug encapsulation efficiency. The optimized NLC formulation was incorporated into Carbopol^® 940 gel, and this arrangement was characterized and compared with the existing marketed gel (Mkt-gel) formulation to assess in vitro drug release, rheology, texture profile, in vivo skin retention and permeation, and stability. Furthermore, prepared and characterized ACE-loaded NLC formulation was evaluated for skin integrity and fitted in a dermatokinetic model. The results of this study confirmed the spherical shape; smooth morphology and nanometric size attested by Zetasizer and scanning and transmission electron microcopy; and stability of the ACE-NLC formulation. The ACE-NLC-gel formulation showed good rheological and texture characteristics, and better skin distribution in the epidermis and dermis. Moreover, ACE-NLC permeated deeper in the skin layers and kept the skin integrity intact. Overall, NLC-based gel formulation of ACE might be a promising nanoscale lipid carrier for topical application when compared with the conventional Mkt-gel formulation.