Spotlighting rising researcher Kasturi Siddhanta: Development of inhalable and parenteral platforms for lung-targeted delivery of oligonucleotides- from microRNAs to self-amplifying RNAs

As one of the world’s most devastating viruses, HIV-1 has killed more than 39 million people, and around two million cases of newly infected individuals are recorded every year. However, no effective vaccine has been developed to stop this pandemic since its onset in the 1980s. Since vaccine development is moving slowly, delivery platforms as an essential element to enhance both the efficiency and efficacy of vaccines have drawn increased attention. Gold nanoparticles (GNPs) as a novel delivery platform has been studied in drug and vaccine delivery. My research goal is to apply this delivery platform in the AIDS vaccine development field for HIV-1 envelope protein-based subunit antigens. We studied different conjugation methods to load antigens on GNPs. First, we tried to directly link an antigen onto GNPs through an introduced cysteine mutation in the antigen, since the thiol group of cysteine can form a covalent bond with GNP. In this direct-linking study, we made several antigen variants with cysteine introduced in different positions of the original antigen. All cysteine variants can be successfully loaded on GNPs, with neutralizing epitopes exposed after bond on GNPs. We found that the terminal cysteine variants (with the cysteine mutation on either end of the antigen) can elicit high antibody response in rabbits; however, the antibody responses from the internal cysteine variants (with the cysteine mutation inside of the antigen) are exceptionally low. We suspected that the antigens loaded on GNPs trough the internal linkage might be too close to the GNP surface, therefore, it might be difficult to cleave these

Viruses typically infiltrate host cells via specialized cellular receptors, a pivotal step that is challenging when suitable permissive cell lines or hosts are unavailable. Leveraging the unique internal replication machinery of negative-stranded (ns) RNA viruses, we demonstrate that purified nucleocapsid (NCs), their functional genomic templates, can directly initiate a complete viral life cycle upon intracellular delivery, bypassing conventional cell surface interaction. We successfully purified vesicular stomatitis virus (VSV) NCs, including those from a G-deleted pseudotyped variant (rVSV-ΔG-TFP). Exogenous delivery of these NCs into cells stimulated gene expression and generated infectious progeny virions (from full-length NCs). Critically, VSV-ΔG-TFP NCs, though self-amplifying, are inherently non-infectious, offering a safer, potentially more effective alternative for a vaccine development platform compared to live/attenuated viruses or mRNA-based systems. Furthermore, these NCs provide a secure method for transporting components of highly pathogenic nsRNA viruses (e.g., Nipah virus), acting as an inherent self-deactivating feature against accidental exposure. This study establishes NCs as a novel, intrinsically safer, and self-amplifying platform for antiviral screening, vaccine development, gene delivery, and biosafety in pathogen research.

Virus-like particles (VLPs) are empty, nanoscale structures morphologically resembling viruses. Internal cavity, noninfectious, and particulate nature with a high density of repeating epitopes, make them an ideal platform for vaccine development and drug delivery. Commercial use of Gardasil-9 and Cervarix showed the usefulness of VLPs in vaccine formulation. Further, chimeric VLPs allow the raising of an immune response against different immunogens and thereby can help reduce the generation of medical or clinical waste. The economically viable production of VLPs significantly impacts their usage, application, and availability. To this end, several hosts have been used and tested. The present review will discuss VLPs produced using different yeasts as fermentation hosts. We also compile a list of studies highlighting the expression and purification of VLPs using a yeast-based platform. We also discuss the advantages of using yeast to generate VLPs over other available systems. Further, the issues or limitations of yeasts for producing VLPs are also summarized. The review also compiles a list of yeast-derived VLP-based vaccines that are presently in public use or in different phases of clinical trials.

Next Generation Immunotherapies – Emerging Strategies for Immune Modulation against Cancer, Infections, and Beyond

Background: The treatment of solid tumours and angiogenic ocular diseases by photodynamic therapy (PDT) requires the injection of a photosensitiser (PS) to destroy target cells through a combination of visible light irradiation and molecular oxygen. There is currently great interest in the development of efficient and specific carrier delivery platforms for systemic PDT. Objective: This article aims to review recent developments in systemic carrier delivery platforms for PDT, with an emphasis on target specificity. Methods: Recent publications, spanning the last five years, concerning delivery carrier platforms for systemic PDT were reviewed, including PS conjugates, dendrimers, micelles, liposomes and nanoparticles. Results/conclusion: PS conjugates and supramolecular delivery platforms can improve PDT selectivity by exploiting cellular and physiological specificities of the targeted tissue. Overexpression of receptors in cancer and angiogenic endothelial cells allows their targeting by affinity-based moieties for the selective uptake of PS conjugates and encapsulating delivery carriers, while the abnormal tumour neovascularisation induces a specific accumulation of heavy weighted PS carriers by enhanced permeability and retention (EPR) effect. In addition, polymeric prodrug delivery platforms triggered by the acidic nature of the tumour environment or the expression of proteases can be designed. Promising results obtained with recent systemic carrier platforms will, in due course, be translated into the clinic for highly efficient and selective PDT protocols.

Development of a novel PTD-mediated IVT-mRNA delivery platform for potential protein replacement therapy of metabolic/genetic disorders

Transdermal insulin delivery in a painless, convenient, and on-demand way remains a long-standing challenge. A variety of smart microneedles (MNs) fabricated by glucose-responsive phenylboronic acid hydrogels have been previously developed to provide painless and autonomous insulin release in response to a glucose level change. However, like the majority of MNs, their transdermal delivery efficiency was still relatively low compared to that with subcutaneous injection. Herein, we report an iontophoresis (ITP)-integrated smart MNs delivery platform with enhanced transdermal delivery efficiency and delivery depth. Carbon nanotubes (CNTs) were induced in the boronate-containing hydrogel to develop a semi-interpenetrating network hydrogel with enhanced stiffness and conductivity. Remarkably, ITP not only facilitated efficient and deeper transdermal delivery of insulin via electroosmosis and electrophoresis but also well-maintained glucose responsiveness. This ITP-combined smart MNs delivery platform, which could provide on-demand insulin delivery in a painless, convenient, and safe way, is promising to achieve persistent glycemic control. Furthermore, transdermal delivery of payloads with a wide size range was achieved by this delivery platform and thus shed light on the development of an efficient transdermal delivery platform with deep skin penetration in a minimally invasive way.

Genomic therapy has emerged as a transformative strategy for the prevention, diagnosis and treatment of a wide array of diseases, including Alzheimer's disease, amyotrophic lateral sclerosis and other CNS-related diseases. Recent developments in chemical strategies and delivery platforms have enhanced the potential of genomic therapies for brain disorders. In this Review, we summarize such strategies, focusing on advances in delivery platforms such as lipid nanoparticles, polymers and oligonucleotide conjugates to facilitate the brain delivery of DNA-based or RNA-based therapeutics into the CNS. We present an overview of the chemical structures and functional moieties of lipids, polymers and oligonucleotides used in these platforms. Lastly, we provide an outlook on future chemical directions to further improve the delivery of genomic medicines to the brain.

Design and development of multi-walled carbon nanotube-liposome drug delivery platforms

Billions of people and many soils across the planet suffer from micronutrient (MN) deficiencies impairing human health. In general, fertilization of deficient soils, according to soil test, with MNs alone and in combination with nitrogen, phosphorous, and potassium (NPK) baseline treatment increases crop yield. The soil applied fertilizer-MN use efficiency (MUE) by crops is <5 % due to a lack of synchronization between the fertilizer-MN release and their crop demand during growth. Nanotechnology and biotechnology have the potential to play a prominent place in transforming agricultural systems and food production worldwide in the coming years. MNs added in microcapsules and nanocapsules, nanomaterials (NMs), and nanoparticles (NPs) are taken up and translocated within plants when grown to maturity, increasing crop yield and MN concentration in plants. Noteworthy, many of the effects of NPs and NMs on crop yield and quality, human health, and associated environmental risks remain to be explored. Increasing MUE requires synchronizing the release of nutrients from fertilizers with crop demand during the growing season. Development of intelligent MN fertilizer delivery platforms (IMNDP) may be possible on the basis of elucidating communication signals between plant roots and soil microorganisms. Important benefits from the development and farm adoption of intelligent MN delivery platforms include increased MUE, reduced fertilizer use, and minimal toxicity and environmental impacts. This article proposes for the first time a novel model for IMNDP to enhance MUE and food quality by enabling the synchronization of MN release from fertilizers according to crop demand.

Recombinant subunit vaccines in general are poor immunogens likely due to the small size of peptides and proteins, combined with the lack or reduced presentation of repetitive motifs and missing complementary signal(s) for optimal triggering of the immune response. Therefore, recombinant subunit vaccines require enhancement by vaccine delivery vehicles in order to attain adequate protective immunity. Particle-based delivery platforms, including particulate antigens and particulate adjuvants, are promising delivery vehicles for modifying the way in which immunogens are presented to both the innate and adaptive immune systems. These particle delivery platforms can also co-deliver non-specific immunostimodulators as additional adjuvants. This paper reviews efforts and advances of the Particle-based delivery platforms in development of vaccines against malaria, a disease that claims over 600,000 lives per year, most of them are children under 5 years of age in sub-Sahara Africa.

Towards alternative platform futures in post-pandemic cities? A case study on platformization and changing socio-spatial relations in on-demand food delivery

Event Abstract Back to Event Influence of molecular architecture in the design and development of a pH-responsive nanoscale hydrogel platform for tumor-targeted drug delivery Angela M. Wagner1, 2 and Nicholas A. Peppas1, 2, 3, 4* 1 The University of Texas at Austin, McKetta Department of Chemical Engineering, United States 2 The University of Texas at Austin, Institute for Biomaterials, Drug Delivery, and Regenerative Medicine, United States 3 The University of Texas at Austin, Biomedical Engineering, United States 4 The University of Texas at Austin, College of Pharmacy, United States The lack of specificity in traditional chemotherapeutic administration typically leads to significant dose-limiting toxicities and requires patients to wait for long periods between treatments. During this time, cancer cells have an opportunity to recover from the treatment and develop multi-drug resistance[1]. Our work holds promise to improve treatment specificity through the use of intelligent nanoscale hydrogels (nanogels) to localize the chemotherapeutic agents (CA) at targeted disease sites via the enhanced permeation and retention effect, ultimately limiting the toxicity to healthy tissues. Further, the nanogel molecular architecture can be tailored to carry a variety of cargos with widely varying physicochemical properties, promote cellular uptake, and release the cargo only in response to the intracellular environment. Nanoparticle-mediated combination therapy offers many advantages including the ability to signal different pathways in the cancer cells, maximize the therapeutic efficacy against specific targets, target different phases of the cell cycle, and overcome efflux-driven mechanisms of resistance[1]. Further, it allows PK/PD to be dictated by the in vivo distribution and cellular uptake of the nanogels rather than the physicochemical properties of the free CAs, ensuring optimal synergistic ratios are delivered to the cytosol[2]. As shown in Fig. 1A, the nanogels are comprised of: 1) a cationic monomer 2-(diethylamino)ethyl methacrylate that imparts the pH-response by ionization of amine pendant groups, 2) a tetraethylene glycol dimethacrylate crosslinker to improve CA retention, 3) an alkyl methacrylate monomer to improve CA-polymer interactions, 4) surface-grafted poly(ethylene glycol) methacrylate to impart serum stability. Nanogels were synthesized using a UV-initiated oil-in-water emulsion polymerization[3] with a 2.5 mol% crosslinking density. The impact of alkyl methacrylate monomer inclusion was investigated through systematic variation of monomer functionality and chain length (methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, butyl methacrylate, and hexyl methacrylate as shown in Fig. 1B). The physical properties of the resulting nanogels were compared using dynamic light scattering, zeta potential, titration, pyrene fluorescence, and red blood cell hemolysis as a function of pH to elicit the influence of polymer composition on swelling ratio, surface charge, pKa, relative hydrophobicity and hydrophile-hydrophobe phase transition, and erythrocyte membrane disruption capability. The therapeutic delivery potential was analyzed using hydrophobic (paclitaxel) and hydrophilic (carboplatin) chemotherapeutic agents. Nanogels were loaded by imbibition at pH 4.0, and the release kinetics were studied by incubating loaded nanogels at pH 7.4 for 2 hr followed by pH 5.5 for 24 hr. The nanogels resulted in well-defined and controllable particle size, morphology, and composition. We demonstrated the tunability of our multicomponent nanogel systems to entrap varied molecular cargos, and showed that the molecular architecture can be rationally designed to respond intelligently to different environments. As shown in Fig. 2a and 2b, inclusion of a hydrophobic monomer significantly altered the resulting nanogel physical properties. Varying both the chain length and steric bulk allowed for precise control over the thermodynamic response (relative swelling ratio), dynamic behavior (nanogel pKa and membrane disruption potential), and CA-polymer interaction (therapeutic delivery potential). Nanogels synthesized with hexyl methacrylate exhibited favorable behavior for intracellular delivery and demonstrated an increase in the therapeutic delivery potential of both hydrophobic and hydrophilic CAs. The 90-nm nanogels (hydrodynamic diameter) exhibited a neutral surface charge and no hemolytic activity in pH 7.4 PBS, indicating stability in a simulated physiological environment and ability to retain the CAs during circulation in the bloodstream. The nanogels swelled to 120-nm in response to acidic pH and demonstrated significant membrane disruption in PBS with pH < 6.8, demonstrating the ability to rapidly release the encapsulated CAs and mediate endosomal rupture in a pH-dependent manner. This work was supported by a grant from the National Institutes of Health (R01-EB-000246-22); The authors would like to acknowledge the assistance of Balark Chethan, Rishabh Shah, and Alina Schroeder

Hydrogels have been extensively used in agriculture to improve crop yields for their excellent properties. However, they are currently used either as pesticide delivery platforms or water retention agents alone; the combination of these two functions into one agricultural hydrogel formulation has never been reported, which is crucial to promote sustainable development in agriculture. Herein, using poly(β-cyclodextrin) and adamantane-grafted poly(acrylic acid) (PAA-Ada) as the host and guest, respectively, an easy operating, multi-responsive, and safer hydrogel delivery system for insecticides is fabricated by the host-guest interaction between cyclodextrin and adamantane, which can load uniformly dispersed insecticides (fipronil, imidacloprid, and thiamethoxam) up to 60%. Benefiting from the carboxyl and hydroxyl groups on polymer chains, different temperatures (25, 35, and 45 °C) and pH values (5.0, 6.8, and 10.0) change the intermolecular forces within the hydrogel network and then the diffusion of the content, finally resulting in controlled release behaviors. Besides, this platform can rapidly release the insecticides in the presence of amyloglucosidase due to its ring-opening effect on cyclodextrin. Moreover, this platform exhibits high water-retaining capacity toward soil, which can increase the maximum water absorption of nutrient soil and quartz sand by 31.6 and 13.9%, respectively, and slows down the water loss. Compared with commercial formulation, this smart system reduces the acute toxicity to non-target organism earthworms by 52.4% and improves the efficacy against target organism aphids by 47.3%, showing better durability, lower environmental toxicity, and higher efficiency. To our knowledge, this is the first idea that simultaneously adopts the water-retaining capacity and controlled release ability of hydrogels to improve insecticide efficacy. In this regard, this smart hydrogel platform holds great potentials as slow-release granules with water-holding ability for protection against insect pests, providing an alternative platform for the sustainable development in green agriculture.

BackgroundVirus-like particles have been regularly used as an antigen delivery system for a number of Plasmodium peptides or proteins. The present study reports the immunogenicity and protective efficacy of bacterium-like particles (BLPs) generated from Lactococcus lactis and loaded with Plasmodium berghei circumsporozoite protein (PbCSP) peptides.MethodsA panel of BLP-PbCSP formulations differing in composition and quantity of B-cell, CD4+ and CD8+ T-cell epitopes of PbCSP were tested in BALB/c mice.ResultsBLP-PbCSP1 induced specific humoral responses but no IFN-γ ELISPOT response, protecting 30-40% of the immunized mice. BLP-PbCSP2, with reduced length of the non-immunogenic part of the T-cell-epitopes construct, increased induction of IFN-γ responses as well as protection up to 60-70%. Compared to controls, lower parasitaemia was observed in unprotected mice immunized with BLP-PbCSP1 or 2, suggestive for partial immunity. Finally, further increase of the number of B-cell epitopes and codon optimization (BLP-PbCSP4) induced the highest anti-CSP antibody levels and number of IFN-γ spots, resulting in sterile immunity in 100% of the immunized mice.ConclusionPresentation of Plasmodium-derived antigens using BLPs as a delivery system induced complete protection in a murine malaria model. Eventually, BLPs have the potential to be used as a novel versatile delivery platform in malaria vaccine development.