Targeted Drug Delivery in Lipid-like Nanocages and Extracellular Vesicles

Targeted macrophage mannose receptor (CD206)-specific protein delivery via engineered extracellular vesicles

Extracellular vesicles (EVs) show great potential for therapeutic delivery to human cells, with a focus on modulating immune responses. The most promising targets for inducing humoral and cellular immunity against a specific antigen are macrophages (Mϕs) and dendritic cells (DCs). Targeting mannose receptors (CD206), which are highly expressed on these antigen-presenting cells, to promote the presentation of specific antigens through EV-mediated uptake, is a promising strategy in clinical immunotherapy. Our study compares two EV-fused anti-CD206 nanobodies in delivering cargo proteins to human activated antigen-presenting cells. We demonstrated that nanobody-functionalized EVs exhibit enhanced interaction and increased uptake by CD206+ cells compared to non-targeted EVs. Furthermore, replacing the full-length vesicular stomatitis virus protein G (VSV-G) with its truncated form, fused to a monoclonal anti-CD206 nanobody, significantly improves the specificity of EV uptake by CD206+ cells. Our study outlines an optimized platform for the production of targeted EVs designed for specific protein delivery to CD206-positive human cells.

Tumor-derived small extracellular vesicles in cancer invasion and metastasis: molecular mechanisms, and clinical significance

The production and release of tumor-derived small extracellular vesicles (TDSEVs) from cancerous cells play a pivotal role in the propagation of cancer, through genetic and biological communication with healthy cells. TDSEVs are known to orchestrate the invasion-metastasis cascade via diverse pathways. Regulation of early metastasis processes, pre-metastatic niche formation, immune system regulation, angiogenesis initiation, extracellular matrix (ECM) remodeling, immune modulation, and epithelial-mesenchymal transition (EMT) are among the pathways regulated by TDSEVs. MicroRNAs (miRs) carried within TDSEVs play a pivotal role as a double-edged sword and can either promote metastasis or inhibit cancer progression. TDSEVs can serve as excellent markers for early detection of tumors, and tumor metastases. From a therapeutic point of view, the risk of cancer metastasis may be reduced by limiting the production of TDSEVs from tumor cells. On the other hand, TDSEVs represent a promising approach for in vivo delivery of therapeutic cargo to tumor cells. The present review article discusses the recent developments and the current views of TDSEVs in the field of cancer research and clinical applications.

Extracellular Vesicles in Chronic Demyelinating Diseases: Prospects in Treatment and Diagnosis of Autoimmune Neurological Disorders

Extracellular vesicles (EVs) represent membrane-enclosed structures that are likely to be secreted by all living cell types in the animal organism, including cells of peripheral (PNS) and central nervous systems (CNS). The ability to cross the blood-brain barrier (BBB) provides the possibility not only for various EV-loaded molecules to be delivered to the brain tissues but also for the CNS-to-periphery transmission of these molecules. Since neural EVs transfer proteins and RNAs are both responsible for functional intercellular communication and involved in the pathogenesis of neurodegenerative diseases, they represent attractive diagnostic and therapeutic targets. Here, we discuss EVs' role in maintaining the living organisms' function and describe deviations in EVs' structure and malfunctioning during various neurodegenerative diseases.

Mechanistic Approach of Nano Carriers for Targeted in Cancer Chemotherapy: A Newer Strategy for Novel Drug Delivery System

The application of nanomedicine represents an innovative approach for the treatment in the modern field of cancer chemotherapy. In the present research work, tamoxifen citrate loaded nanolipid vesicles were prepared conjugated with phosphoethanolamine as the linker molecule, and the specific antibody was tagged with the linker molecule on the bilayer surface of the vesicles. The main objective of this study is to determine the efficacy and biological behavior of antibody conjugated nanoliposome in breast cancer cell lines. Percentage of drug loading and loading efficiency was done and their results were compared to theoretical drug loading. The average diameter of those vesicles was within the 100 nm range, which is revealed in FESEM and TEM images and their lamellarity was observed in cryo-TEM images. The hydrodynamic diameter was done by particle size analysis and the surface charge was determined by the zeta potential parameter. Predominant cellular uptake was observed for antibody conjugated nanolipid vesicles in MCF-7 and MDA-MB-453 human breast cancer cell lines. A cellular apoptosis assay was conducted by flow cytometer (FACS). All experimental data would be more beneficial for the treatment of breast cancer chemotherapy. Further studies are warranted to investigate the efficacy and safety of antibody conjugated nanolipid vesicles in vivo for breast cancer animal model.

Hybrid Complexes of Photosensitizers with Luminescent Nanoparticles: Design of the Structure

Increasing the efficiency of the photodynamic action of the dyes used in photodynamic therapy is crucial in the field of modern biomedicine. There are two main approaches used to increase the efficiency of photosensitizers. The first one is targeted delivery to the object of photodynamic action, while the second one is increasing the absorption capacity of the molecule. Both approaches can be implemented by producing dye-nanoparticle conjugates. In this review, we focus on the features of the latter approach, when nanoparticles act as a light-harvesting agent and nonradiatively transfer the electronic excitation energy to a photosensitizer molecule. We will consider the hybrid photosensitizer-quantum dot complexes with energy transfer occurring according to the inductive-resonance mechanism as an example. The principle consisting in optimizing the design of hybrid complexes is proposed after an analysis of the published data; the parameters affecting the efficiency of energy transfer and the generation of reactive oxygen species in such systems are described.

Targeting Extracellular Vesicles to Dendritic Cells and Macrophages

Targeting protein therapeutics to specific cells and tissues is a major challenge in modern medicine. Improving the specificity of protein therapeutic delivery will significantly enhance efficiency in drug development. One of the promising tools for protein delivery is extracellular vesicles (EVs) that are enveloped by a complex lipid bilayer. EVs are secreted by almost all cell types and possess significant advantages: biocompatibility, stability, and the ability to penetrate the blood-brain barrier. Overexpression of the vesicular stomatitis virus protein G (VSV-G) was shown to promote EV formation by the producer cell. We have developed an EV-based system for targeted delivery of protein cargoes to antigen-presenting cells (APCs). In this study, we show that attachment of a recombinant llama nanobody α-CD206 to the N-terminus of a truncated VSV-G increases the selectivity of EV cargo delivery mainly to APCs. These results highlight the outstanding technological and biomedical potential of EV-based delivery systems for correcting the immune response in patients with autoimmune, viral, and oncological diseases.

Reprogramming Extracellular Vesicles for Protein Therapeutics Delivery

Delivering protein therapeutics specifically into target cells and tissues is a promising avenue in medicine. Advancing this process will significantly enhance the efficiency of the designed drugs. In this regard, natural membrane-based systems are of particular interest. Extracellular vesicles (EVs), being the bilayer lipid particles secreted by almost all types of cells, have several principal advantages: biocompatibility, carrier stability, and blood-brain barrier penetrability, which make them a perspective tool for protein therapeutic delivery. Here, we evaluate the engineered genetically encoded EVs produced by a human cell line, which allow efficient cargo loading. In the devised system, the protein of interest is captured by self-assembling structures, i.e., "enveloped protein nanocages" (EPN). In their turn, EPNs are encapsulated in fusogenic EVs by the overexpression of vesicular stomatitis virus G protein (VSV-G). The proteomic profiles of different engineered EVs were determined for a comprehensive evaluation of their therapeutic potential. EVs loading mediated by bio-safe Fos-Jun heterodimerization demonstrates an increased efficacy of active cargo loading and delivery into target cells. Our results emphasize the outstanding technological and biomedical potential of the engineered EV systems, including their application in adoptive cell transfer and targeted cell reprogramming.

Biomimetic nanovesicle design for cardiac tissue repair

Cardiovascular disease is a major cause of mortality and morbidity worldwide. Exosome therapies are promising for cardiac repair. Exosomes transfer cargo between cells, have high uptake by native cells and are ideal natural carriers for proteins and nucleic acids. Despite their proreparative potential, exosome production is dependent on parent cell state with typically low yields and cargo variability. Therefore, there is potential value in engineering exosomes to maximize their benefits by delivering customized, potent cargo for cardiovascular disease. Here, we outline several methods of exosome engineering focusing on three important aspects: optimizing cargo, homing to target tissue and minimizing clearance. Finally, we put these methods in context of the cardiac field and discuss the future potential of vesicle design.

PediTools Electronic Growth Chart Calculators: Applications in Clinical Care, Research, and Quality Improvement

BACKGROUND

Parameterization of pediatric growth charts allows precise quantitation of growth metrics that would be difficult or impossible with traditional paper charts. However, limited availability of growth chart calculators for use by clinicians and clinical researchers currently restricts broader application.

OBJECTIVE

The aim of this study was to assess the deployment of electronic calculators for growth charts using the lambda-mu-sigma (LMS) parameterization method, with examples of their utilization for patient care delivery, clinical research, and quality improvement projects.

METHODS

The publicly accessible PediTools website of clinical calculators was developed to allow LMS-based calculations on anthropometric measurements of individual patients. Similar calculations were applied in a retrospective study of a population of patients from 7 Massachusetts neonatal intensive care units (NICUs) to compare interhospital growth outcomes (change in weight Z-score from birth to discharge [∆Z weight]) and their association with gestational age at birth. At 1 hospital, a bundle of quality improvement interventions targeting improved growth was implemented, and the outcomes were assessed prospectively via monitoring of ∆Z weight pre- and postintervention.

RESULTS

The PediTools website was launched in January 2012, and as of June 2019, it received over 500,000 page views per month, with users from over 21 countries. A retrospective analysis of 7975 patients at 7 Massachusetts NICUs, born between 2006 and 2011, at 23 to 34 completed weeks gestation identified an overall ∆Z weight from birth to discharge of -0.81 (P<.001). However, the degree of ∆Z weight differed significantly by hospital, ranging from -0.56 to -1.05 (P<.001). Also identified was the association between inferior growth outcomes and lower gestational age at birth, as well as that the degree of association between ∆Z weight and gestation at birth also differed by hospital. At 1 hospital, implementing a bundle of interventions targeting growth resulted in a significant and sustained reduction in loss of weight Z-score from birth to discharge.

CONCLUSIONS

LMS-based anthropometric measurement calculation tools on a public website have been widely utilized. Application in a retrospective clinical study on a large dataset demonstrated inferior growth at lower gestational age and interhospital variation in growth outcomes. Change in weight Z-score has potential utility as an outcome measure for monitoring clinical quality improvement. We also announce the release of open-source computer code written in R to allow other clinicians and clinical researchers to easily perform similar analyses.