Targeting Peptides: The New Generation of Targeted Drug Delivery Systems

In silico, in vitro and in vivo toxicity assessment of the antitumoral peptide GK-1

Peptide drugs have emerged as an attractive alternative for cancer treatment due to their potency, high specificity, general safety and low cost. GK-1 is a linear 18 amino acid peptide with proven immunomodulator, antitumor and antimetastatic capacity in animal models. Preclinical toxicity studies for its use as a vaccine adjuvant demonstrated its safety in various assay systems, but a comprehensive exploration of its toxicity profile is required to be used in cancer immunotherapy. Therefore, in the present work, the potential toxicity of GK-1 was predicted with ToxinPred 3.0 software, and its in vitro cytotoxicity, and single-dose and repeated-dose toxicity by subcutaneous route in mice were experimentally assessed. GK-1 peptide was predicted as a non-toxic and did not exhibit in vitro cytotoxicity for several non-tumor and tumor cell lines and primary cell cultures at concentrations up to 500 µM, reinforcing previous studies pointing that the antitumoral effect of GK-1 was not mediated by tumor cell cytotoxicity. The single-dose toxicity study did not evidence local or systemic toxicity up to the maximum tested dose of 1000 mg/kg. Moreover, no toxic effects were observed in the repeated-dose toxicity study based on four doses administered weekly at up to 300 mg/kg. Considering that GK-1 is effective in triple-negative breast cancer and melanoma models in mice at doses as low as 5 mg/kg, the present results support the safety of GK-1 as an antitumoral peptide candidate.

A comprehensive review on targeted therapies for triple negative breast cancer: an evidence-based treatment guideline

Triple-negative breast cancer (TNBC) is an aggressive malignancy characterized by limited therapeutic options and poor prognosis. Despite advancements in precision oncology, conventional chemotherapy remains the cornerstone of TNBC treatment, often accompanied by debilitating side effects and suboptimal outcomes. This review presents a comprehensive analysis of clinical trials on targeted therapies, aiming to establish a novel, evidence-based treatment strategy exclusively leveraging molecularly targeted agents. By integrating patient-specific genetic profiles with therapeutic responses observed across various clinical trial phases, this approach seeks to optimize efficacy while minimizing toxicity. The proposed targeted therapy combinations hold significant potential to revolutionize TNBC treatment, offering a paradigm shift toward precision medicine and improved patient outcomes.

Peptide-driven strategies against lung cancer

Lung cancer remains one of the most significant global health challenges, accounting for 18 % of all cancer-related deaths. While risk factors such as heavy metal exposure and cigarette smoking are well-known contributors, the limitations of conventional treatments including severe side effects and drug resistance highlight the urgent need for more targeted and safer therapeutic options. In this context, peptides have emerged as a novel, precise, and effective class of therapies for lung cancer treatment. They have shown promise in limiting lung cancer progression by targeting key molecular pathways involved in tumour growth. Anti-non-small cell lung cancer peptides that specifically target proteins such as EGFR, TP53, BRAF, MET, ROS1, and ALK have demonstrated potential in improving lung cancer outcomes. Additionally, anti-inflammatory and apoptosis-inducing peptides offer further therapeutic benefits. This review provides a comprehensive overview of the peptides currently in use or under investigation for the treatment of lung cancer, highlighting their mechanisms of action and therapeutic potential. As research continues to advance, peptides are poised to become a promising new therapeutic option in the fight against lung cancer.

Surface modified proteins and peptides for targeted drug delivery

Surface modification of proteins and peptides has emerged as a promising strategy to enhance their therapeutic efficacy and target specificity. This chapter delves into the various techniques employed to modify the surface properties of these biomolecules, including chemical conjugation, site-specific mutagenesis, and peptide synthesis. The focus is on strategies that improve drug delivery to specific target sites, such as tumor cells or inflamed tissues. By modifying surface properties, it is possible to enhance drug stability, reduce immunogenicity, and prolong circulation time. This chapter explores the latest advancements in this field and discusses the potential applications of surface-modified proteins and peptides in the development of novel therapeutic agents.

Peptide-Functionalized Lipid Nanoparticles for Targeted Systemic mRNA Delivery to the Brain

Systemic delivery of large nucleic acids, such as mRNA, to the brain remains challenging in part due to the blood-brain barrier (BBB) and the tendency of delivery vehicles to accumulate in the liver. Here, we design a peptide-functionalized lipid nanoparticle (LNP) platform for targeted mRNA delivery to the brain. We utilize click chemistry to functionalize LNPs with peptides that target receptors overexpressed on brain endothelial cells and neurons, namely the RVG29, T7, AP2, and mApoE peptides. We evaluate the effect of LNP targeting on brain endothelial and neuronal cell transfection in vitro, investigating factors such as serum protein adsorption, intracellular trafficking, endothelial transcytosis, and exosome secretion. Finally, we show that LNP peptide functionalization enhances mRNA transfection in the mouse brain and reduces hepatic delivery after systemic administration. Specifically, RVG29 LNPs improved neuronal transfection in vivo, establishing its potential as a nonviral platform for delivering mRNA to the brain.

The organoid modeling approach to understanding the mechanisms underlying neurodegeneration: A comprehensive review

Neurodegenerative diseases (NDs) are severe disorders of the nervous system, and their causes are still not completely understood. Modeling the complex pathological mechanisms underlying NDs has long posed a significant challenge, as traditional in vitro and animal models often fail to accurately recapitulate the disease phenotypes observed in humans; however, the rise of organoid technology has opened new approaches for developing innovative disease models that can better capture the nuances of the human nervous system. Organoid platforms hold promise for contributing to the design of future clinical trials and advancing our understanding of these devastating neurological conditions and accelerate the discovery of effective, personalized therapies. This comprehensive review discusses the recent advancements in neural organoid technology and explores the potential of patient-derived organoids for modeling NDs conditions and presents findings related to the mechanisms of their development or progress.

Poly(Epsilon-Lysine) Dendrons Inhibit Proliferation in HER2-Overexpressing SKBR3 Breast Cancer Cells at Levels Higher than the Low-Expressing MDA-MB-231 Phenotype and Independently from the Presentation of HER2 Bioligands in Their Structure

Among the known breast cancers, the subtype with HER2 receptors-overexpressing cells is associated with a poor prognosis. The adopted monoclonal antibody Trastuzumab has improved clinical outcomes, but it is associated with drug resistance and relatively high costs. The present work adopted the peptide solid-phase synthesis method to synthesise branched poly(ε-lysine) peptide dendrons with 8 branching arms integrating, at their carboxy terminal molecular root, either an arginine or the HER2 receptor-binding sequence LSYCCK or the scramble sequence CSCLYK. These dendrons were synthesised in quantities higher than 100 mg/batch and with a purity exceeding 95%. When tested with two types of breast cancer cells, the dendrons led to levels of inhibition in the HER2 receptor-overexpressing breast cancer cells (SKBR3) comparable to Trastuzumab and higher than breast cancer cells with low receptor expression (MDA-MB-231) where inhibition was more moderate. Noticeably, the presence of the amino acid sequence LSYCCK at the dendron molecular root did not appear to produce any additional inhibitory effect. This was demonstrated also when the scramble sequence CSCLYK was integrated into the dendron and by the lack of any antiproliferative effect by the control linear target sequence. The specific inhibitory effect on proliferation was finally proven by the absence of cytotoxicity and normal expression of the cell migration marker N-Cadherin. Therefore, the present study shows the potential of poly(ε-lysine) dendrons as a cost-effective alternative to Trastuzumab in the treatment of HER2-positive breast cancer.

Synthetic Nanoassemblies for Regulating Organelles: From Molecular Design to Precision Therapeutics

Each organelle referring to a complex multiorder architecture executes respective biological processes via its distinct spatial organization and internal microenvironment. As the assembly of biomolecules is the structural basis of living cells, creating synthetic nanoassemblies with specific physicochemical and morphological properties in living cells to interfere or couple with the natural organelle architectures has attracted great attention in precision therapeutics of cancers. In this review, we give an overview of the latest advances in the synthetic nanoassemblies for precise organelle regulation, including the formation mechanisms, triggering strategies, and biomedical applications in precision therapeutics. We summarize the emerging material systems, including polymers, peptides, and deoxyribonucleic acids (DNAs), and their respective intermolecular interactions for intercellular synthetic nanoassemblies, and highlight their design principles in constructing precursors that assemble into synthetic nanoassemblies targeting specific organelles in the complex cellular environment. We further showcase the developed intracellular synthetic nanoassemblies targeting specific organelles including mitochondria, the endoplasmic reticulum, lysosome, Golgi apparatus, and nucleus and describe their underlying mechanisms for organelle regulation and precision therapeutics for cancer. Last, the essential challenges in this field and prospects for future precision therapeutics of synthetic nanoassemblies are discussed. This review should facilitate the rational design of organelle-targeting synthetic nanoassemblies and the comprehensive recognition of organelles by materials and contribute to the deep understanding and application of the synthetic nanoassemblies for precision therapeutics.

Design and investigation of novel iridoid-based peptide conjugates for targeting EGFR and its mutants L858R and T790M/L858R/C797S: an in silico study

In this work, we designed novel peptide conjugates with plant-based iridoid and lichen-derived depside derivatives to target the wild-type EGFR (WT) and its mutants, L858R and T790M/L858R/C797S triple mutant. These mutations are often expressed in multiple cancers, particularly lung cancer. Specifically, the iridoids included 7-deoxyloganetic acid (7-DGA) and loganic acid (LG), while the depside derivative was sekikaic acid (SK). These compounds are known for their innate anticancer properties and were conjugated with two separate peptide sequences KLPGWSG (K) and YSIPKSS (Y). These sequences have been shown to target EGFR in previous phage display library screening, although the mechanism is unknown. Thus, we created the di-conjugates for dual targeting and investigated their interactions of the di-conjugates and that of the neat peptides with the kinase domain of EGFR (WT) and the two mutants using molecular docking, molecular dynamics (MD) simulations, and MM-GBSA analysis. Docking studies revealed that the (7-DGA)2-K showed the highest binding affinity at - 9.3 kcal/mol with the L858R mutant, while (LG)2-Y displayed the highest binding affinity at - 9.0 kcal/mol for the triple mutant receptor. Our results indicated that several of the conjugates interacted with crucial residues of the kinase domain, including ASP855 and THR854 (activation loop), MET793 and PRO794 (hinge region), ARG841 (catalytic loop), and LYS728 and LEU718 of the glycine-rich P-loop. Interestingly, strong hydrophobic interactions were also observed with the C-terminal tail residues, such as PHE997 and ALA1000 as well as with ARG999 for the YSIPKSS peptide and most of the conjugates. The hydroxyl group of the cyclopentane ring and the oxygen of the pyran ring of the (7-DGA)2-peptide conjugates contributed to binding particularly in the hinge region, while the peptide components formed an extended structure that bound well into the C-lobe. The (SK)2-Y di-conjugate and KLPGWSG peptide formed hydrogen bonds with the SER797 residue of the triple mutant. Overall, our results show that the (7-DGA)2-K, di-conjugate, the (7-DGA)2-Y di-conjugate, and the neat YSIPKSS demonstrated strong and stable binding with the L858R mutant and the highly resistant triple mutant EGFR, respectively. The novel designed conjugates demonstrate potential for further optimization for laboratory studies aimed at developing new therapeutics for targeting specific EGFR mutant expressing cells.

The future of genetic medicines delivered via targeted lipid nanoparticles to leukocytes

Genetic medicines hold vast therapeutic potential, offering the ability to silence or induce gene expression, knock out genes, and even edit DNA fragments. Applying these therapeutic modalities to leukocytes offers a promising path for treating various conditions yet overcoming the obstacles of specific and efficient delivery to leukocytes remains a major bottleneck in their clinical translation. Lipid nanoparticles (LNPs) have emerged as the leading delivery system for nucleic acids due to their remarkable versatility and ability to improve their in vivo stability, pharmacokinetics, and therapeutic benefits. Equipping LNPs with targeting moieties can promote their specific cellular uptake and internalization to leukocytes, making targeted LNPs (tLNPs) an inseparable part of developing leukocyte-targeted gene therapy. However, despite the significant advancements in research, genetic medicines for leukocytes using targeted delivery approaches have not been translated into the clinic yet. Herein, we discuss the important aspects of designing tLNPs and highlight the considerations for choosing an appropriate bioconjugation strategy and targeting moiety. Furthermore, we provide our insights on limiting challenges and identify key areas for further research to advance these exciting therapies for patient care.

Nanogels: Recent Advances in Synthesis and Biomedical Applications

In the context of advanced nanomaterials research, nanogels (NGs) have recently gained broad attention for their versatility and promising biomedical applications. To date, a significant number of NGs have been developed to meet the growing demands in various fields of biomedical research. Summarizing preparation methods, physicochemical and biological properties, and recent applications of NGs may be useful to help explore new directions for their development. This article presents a comprehensive overview of the latest NG synthesis methodologies, highlighting advances in formulation with different types of hydrophilic or amphiphilic polymers. It also underlines recent biomedical applications of NGs in drug delivery and imaging, with a short section dedicated to biosafety considerations of these innovative nanomaterials. In conclusion, this article summarizes recent innovations in NG synthesis and their numerous applications, highlighting their considerable potential in the biomedical field.

Nanoassemblies designed for efficient nuclear targeting

One of the key aspects of coping efficiently with complex pathological conditions is delivering the desired therapeutic compounds with precision in both space and time. Therefore, the focus on nuclear-targeted delivery systems has emerged as a promising strategy with high potential, particularly in gene therapy and cancer treatment. Here, we explore the design of supramolecular nanoassemblies as vehicles to deliver specific compounds to the nucleus, with the special focus on polymer and peptide-based carriers that expose nuclear localization signals. Such nanoassemblies aim at maximizing the concentration of genetic and therapeutic agents within the nucleus, thereby optimizing treatment outcomes while minimizing off-target effects. A complex scenario of conditions, including cellular uptake, endosomal escape, and nuclear translocation, requires fine tuning of the nanocarriers' properties. First, we introduce the principles of nuclear import and the role of nuclear pore complexes that reveal strategies for targeting nanosystems to the nucleus. Then, we provide an overview of cargoes that rely on nuclear localization for optimal activity as their integrity and accumulation are crucial parameters to consider when designing a suitable delivery system. Considering that they are in their early stages of research, we present various cargo-loaded peptide- and polymer nanoassemblies that promote nuclear targeting, emphasizing their potential to enhance therapeutic response. Finally, we briefly discuss further advancements for more precise and effective nuclear delivery.

A Dynamic and Effective Peptide-Based Strategy for Promptly Addressing Emerging SARS-CoV-2 Variants of Concern

Genomic surveillance based on sequencing the entire genetic code of SARS-CoV-2 involves monitoring and studying genetic changes and variations in disease-causing organisms such as viruses and bacteria. By tracing the virus, it is possible to prevent epidemic spread in the community, ensuring a 'precision public health' strategy. A peptide-based design was applied to provide an efficacious strategy that is able to counteract any emerging viral variant of concern dynamically and promptly to affect the outcomes of a pandemic at an early stage while waiting for the production of the anti-variant-specific vaccine, which require longer times. The inhibition of the interaction between the receptor-binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and one of the cellular receptors (DPP4) that its receptors routinely bind to infect human cells is an intriguing therapeutic approach to prevent the virus from entering human cells. Among the other modalities developed for this purpose, peptides surely offer unique advantages, including ease of synthesis, serum stability, low immunogenicity and toxicity, and small production and distribution chain costs. Here, we obtained a potent new inhibitor based on the rearrangement of a previously identified peptide that has been rationally designed on a cell dipeptidyl peptidase 4 (DPP4) sequence, a ubiquitous membrane protein known to bind the RBD-SPIKE domain of the virus. This novel peptide (named DPP4-derived), conceived as an endogenous "drug", is capable of targeting the latest tested variants with a high affinity, reducing the VSV* DG-Fluc pseudovirus Omicron's infection capacity by up to 14%, as revealed by in vitro testing in human Calu-3 cells. Surface plasmon resonance (SPR) confirmed the binding affinity of the new DPP4-derived peptide with Omicron variant RBD.

Peptide pharmacology: Pioneering interventions for alcohol use disorder

Alcohol use disorder (AUD) is a substantial public health issue, with few treatment choices and a high social cost. This review investigates the possibility of peptide pharmacology as a new treatment for AUD. Peptides, or short chains of amino acids, provide specific manipulation of neuronal pathways involved in addiction, such as the opioid, corticotropin-releasing factor (CRF), neuropeptide Y (NPY), and glutamate systems. Preclinical research has shown that peptide-based therapies can reduce alcohol intake, demand, and relapse in animal models of AUD. Opioid peptides like β-endorphin and enkephalins affect alcohol reward processing by interacting with µ, ∂, and κ opioid receptors. CRF peptides reduce stress-induced alcohol-seeking behavior by targeting the dysregulated CRF system. NPY and associated peptides reduce cravings and anxiety by regulating stress and emotional processing. Peptide-based therapies have strong translational potential, as evidenced by early clinical trial results. There are also challenges in converting preclinical discoveries into clinical practice, such as establishing the safety, tolerability, and effectiveness of peptide therapies in humans. Future initiatives include identifying new peptide targets, optimizing pharmacokinetics, and incorporating peptide-based therapies into established therapy methods. Overall, peptide pharmacology represents a potential prospect in AUD therapy, as it provides tailored therapies that address the complex neurobiological pathways that underpin addiction.

Anti-angiogenic biomolecules in neovascular age-related macular degeneration; therapeutics and drug delivery systems

Blindness in the elderly is often caused by age-related macular degeneration (AMD). The advanced type of AMD known as neovascular AMD (nAMD) has been linked to being the predominant cause of visual impairment in these people. Multiple neovascular structures including choroidal neovascular (CNV) membranes, fluid exudation, hemorrhages, and subretinal fibrosis, are diagnostic of nAMD. These pathological alterations ultimately lead to anatomical and visual loss. It is known that vascular endothelial growth factor (VEGF), a type of proangiogenic factor, mediates the pathological process underlying nAMD. Therefore, various therapies have evolved to directly target the disease. In this review article, an attempt has been made to discuss general explanations about this disease, all common treatment methods based on anti-VEGF drugs, and the use of drug delivery systems in the treatment of AMD. Initially, the pathophysiology, angiogenesis, and different types of AMD were described. Then we described current treatments and future treatment prospects for AMD and outlined the advantages and disadvantages of each. In this context, we first examined the types of therapeutic biomolecules and anti-VEGF drugs that are used in the treatment of AMD. These biomolecules include aptamers, monoclonal antibodies, small interfering RNAs, microRNAs, peptides, fusion proteins, nanobodies, and other therapeutic biomolecules. Finally, we described drug delivery systems based on liposomes, nanomicelles, nanoemulsions, nanoparticles, cyclodextrin, dendrimers, and composite vehicles that are used in AMD therapy.

Pioglitazone Phases and Metabolic Effects in Nanoparticle-Treated Cells Analyzed via Rapid Visualization of FLIM Images

Fluorescence lifetime imaging microscopy (FLIM) has proven to be a useful method for analyzing various aspects of material science and biology, like the supramolecular organization of (slightly) fluorescent compounds or the metabolic activity in non-labeled cells; in particular, FLIM phasor analysis (phasor-FLIM) has the potential for an intuitive representation of complex fluorescence decays and therefore of the analyzed properties. Here we present and make available tools to fully exploit this potential, in particular by coding via hue, saturation, and intensity the phasor positions and their weights both in the phasor plot and in the microscope image. We apply these tools to analyze FLIM data acquired via two-photon microscopy to visualize: (i) different phases of the drug pioglitazone (PGZ) in solutions and/or crystals, (ii) the position in the phasor plot of non-labelled poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), and (iii) the effect of PGZ or PGZ-containing NPs on the metabolism of insulinoma (INS-1 E) model cells. PGZ is recognized for its efficacy in addressing insulin resistance and hyperglycemia in type 2 diabetes mellitus, and polymeric nanoparticles offer versatile platforms for drug delivery due to their biocompatibility and controlled release kinetics. This study lays the foundation for a better understanding via phasor-FLIM of the organization and effects of drugs, in particular, PGZ, within NPs, aiming at better control of encapsulation and pharmacokinetics, and potentially at novel anti-diabetics theragnostic nanotools.

Design and applications of polymer-like peptides in biomedical nanogels

INTRODUCTION

Polymer nanogels are among the most promising nanoplatforms for use in biomedical applications. The substantial interest for these drug carriers is to enhance the transportation of bioactive substances, reduce the side effects, and achieve optimal action on the curative sites by targeting delivery and triggering the release of the drugs in a controlled and continuous mode.

AREA COVERED

The review discusses the opportunities, applications, and challenges of synthetic polypeptide nanogels in biomedicine, with an emphasis on the recent progress in cancer therapy. It is evidenced by the development of polypeptide nanogels for better controlled drug delivery and release, in complex in vivo microenvironments in biomedical applications.

EXPERT OPINION

Polypeptide nanogels can be developed by choosing the amino acids from the peptide structure that are suitable for the type of application. Using a stimulus - sensitive peptide nanogel, it is possible to obtain the appropriate transport and release of the drug, as well as to achieve desirable therapeutic effects, including safety, specificity, and efficiency. The final system represents an innovative way for local and sustained drug delivery at a specific site of the body.

Applications of peptides in nanosystems for diagnosing and managing bacterial sepsis

Sepsis represents a critical medical condition stemming from an imbalanced host immune response to infections, which is linked to a significant burden of disease. Despite substantial efforts in laboratory and clinical research, sepsis remains a prominent contributor to mortality worldwide. Nanotechnology presents innovative opportunities for the advancement of sepsis diagnosis and treatment. Due to their unique properties, including diversity, ease of synthesis, biocompatibility, high specificity, and excellent pharmacological efficacy, peptides hold great potential as part of nanotechnology approaches against sepsis. Herein, we present a comprehensive and up-to-date review of the applications of peptides in nanosystems for combating sepsis, with the potential to expedite diagnosis and enhance management outcomes. Firstly, sepsis pathophysiology, antisepsis drug targets, current modalities in management and diagnosis with their limitations, and the potential of peptides to advance the diagnosis and management of sepsis have been adequately addressed. The applications have been organized into diagnostic or managing applications, with the last one being further sub-organized into nano-delivered bioactive peptides with antimicrobial or anti-inflammatory activity, peptides as targeting moieties on the surface of nanosystems against sepsis, and peptides as nanocarriers for antisepsis agents. The studies have been grouped thematically and discussed, emphasizing the constructed nanosystem, physicochemical properties, and peptide-imparted enhancement in diagnostic and therapeutic efficacy. The strengths, limitations, and research gaps in each section have been elaborated. Finally, current challenges and potential future paths to enhance the use of peptides in nanosystems for combating sepsis have been deliberately spotlighted. This review reaffirms peptides' potential as promising biomaterials within nanotechnology strategies aimed at improving sepsis diagnosis and management.

Peptide-ligand conjugate based immunotherapeutic approach for targeted dismissal of non-structural protein 1 of dengue virus: A novel therapeutic solution for mild and severe dengue infections

Dengue virus infection has significantly increased, with reported cases soaring from 505,430 in 2000 to 2,809,818 in 2022, emphasizing the need for effective treatments. Among the eleven structural and non-structural proteins of DENV, Non-structural protein 1 (NS1) has emerged as a promising target due to its diverse role in modulating the immune response, inducing vascular leakage, and facilitating viral replication and assembly. Monoclonal antibodies are the sole therapeutics to target NS1, but concerns about their cross-reactivity persist. Given these concerns, our study focuses on designing a novel Peptide Ligand Conjugate (PLC) as a potential alternative immunotherapeutic agent against NS1. This PLC aims to mediate the immune elimination of soluble NS1 and NS1-presenting DENV-infected host cells by pre-existing vaccine-induced immunity. By employing the High Throughput Virtual Screening (HTVS) method, QikProp analysis, and Molecular Dynamics studies, we identified three hits from Asinex Biodesigned Ligands out of 220,177 compounds that show strong binding affinity towards the monoclonal binding site of NS1 protein. After a rigorous analysis of physicochemical characteristics, antigenicity, allergenicity, and toxicity using various servers, we selected two peptides: the minimum epitopic region of the Diphtheria and Tetanus toxins as the peptide components of the PLCs. A non-cleavable, non-reactive oxime linker connected the ligand with the peptide through oxime and amide bonds. DPT vaccine is widely used in dengue-endemic countries, and it has been reported that antibodies titer against MER of Diphtheria toxin and Tetanus toxins persist lifelong in DPT-vaccinated people. Therefore, once the rationally designed PLCs bind to NS1 through the ligands, the peptide will induce an immune response against NS1 by triggering pre-existing DPT antibodies and activating memory cells. This orchestrated immune response will destroy soluble NS1 and NS1-expressing DENV-infected cells, thereby reducing the illness of severe dengue hemorrhagic fever and the DENV infection, respectively. Given the increasing demand for new therapeutics for DENV treatment, further investigation into this novel immune-therapeutic strategy may offer a new avenue for treating mild and severe dengue infections.

Straight to the point: targeted mRNA-delivery to immune cells for improved vaccine design

With the deepening of our understanding of adaptive immunity at the cellular and molecular level, targeting antigens directly to immune cells has proven to be a successful strategy to develop innovative and potent vaccines. Indeed, it offers the potential to increase vaccine potency and/or modulate immune response quality while reducing off-target effects. With mRNA-vaccines establishing themselves as a versatile technology for future applications, in the last years several approaches have been explored to target nanoparticles-enabled mRNA-delivery systems to immune cells, with a focus on dendritic cells. Dendritic cells (DCs) are the most potent antigen presenting cells and key mediators of B- and T-cell immunity, and therefore considered as an ideal target for cell-specific antigen delivery. Indeed, improved potency of DC-targeted vaccines has been proved in vitro and in vivo. This review discusses the potential specific targets for immune system-directed mRNA delivery, as well as the different targeting ligand classes and delivery systems used for this purpose.

Targeted Bioluminescent Imaging of Pancreatic Ductal Adenocarcinoma Using Nanocarrier-Complexed EGFR-Binding Affibody-Gaussia Luciferase Fusion Protein

In vivo imaging has enabled impressive advances in biological research, both preclinical and clinical, and researchers have an arsenal of imaging methods available. Bioluminescence imaging is an advantageous method for in vivo studies that allows for the simple acquisition of images with low background signals. Researchers have increasingly been looking for ways to improve bioluminescent imaging for in vivo applications, which we sought to achieve by developing a bioluminescent probe that could specifically target cells of interest. We chose pancreatic ductal adenocarcinoma (PDAC) as the disease model because it is the most common type of pancreatic cancer and has an extremely low survival rate. We targeted the epidermal growth factor receptor (EGFR), which is frequently overexpressed in pancreatic cancer cells, using an EGFR-specific affibody to selectively identify PDAC cells and delivered a Gaussia luciferase (GLuc) bioluminescent protein for imaging by engineering a fusion protein with both the affibody and the bioluminescent protein. This fusion protein was then complexed with a G5-PAMAM dendrimer nanocarrier. The dendrimer was used to improve the protein stability in vivo and increase signal strength. Our targeted bioluminescent complex had an enhanced uptake into PDAC cells in vitro and localized to PDAC tumors in vivo in pancreatic cancer xenograft mice. The bioluminescent complexes could delineate the tumor shape, identify multiple masses, and locate metastases. Through this work, an EGFR-targeted bioluminescent-dendrimer complex enabled the straightforward identification and imaging of pancreatic cancer cells in vivo in preclinical models. This argues for the targeted nanocarrier-mediated delivery of bioluminescent proteins as a way to improve in vivo bioluminescent imaging.