Design and Development of Biomimetic Nanovesicles Using a Microfluidic Approach

Engineering aspects of lipid-based delivery systems: In vivo gene delivery, safety criteria, and translation strategies

Defects in the genome cause genetic diseases and can be treated with gene therapy. Due to the limitations encountered in gene delivery, lipid-based supramolecular colloidal materials have emerged as promising gene carrier systems. In their non-functionalized form, lipid nanoparticles often demonstrate lower transgene expression efficiency, leading to suboptimal therapeutic outcomes, specifically through reduced percentages of cells expressing the transgene. Due to chemically active substituents, the engineering of delivery systems for genetic drugs with specific chemical ligands steps forward as an innovative strategy to tackle the drawbacks and enhance their therapeutic efficacy. Despite intense investigations into functionalization strategies, the clinical outcome of such therapies still needs to be improved. Here, we highlight and comprehensively review engineering aspects for functionalizing lipid-based delivery systems and their therapeutic efficacy for developing novel genetic cargoes to provide a full snapshot of the translation from the bench to the clinics. We outline existing challenges in the delivery and internalization processes and narrate recent advances in the functionalization of lipid-based delivery systems for nucleic acids to enhance their therapeutic efficacy and safety. Moreover, we address clinical trials using these vectors to expand their clinical use and principal safety concerns.

Biomimetic nanoparticles for effective Celastrol delivery to targeted treatment of rheumatoid arthritis through the ROS-NF-κB inflammasome axis

Previous study has indicated that Celastrol (Cel) has various physiological and pharmacological effects, including antibacterial, antioxidant, pro-apoptotic, anticancer and anti-rheumatoid arthritis (RA) effects. However, low water solubility, low oral bioavailability, narrow treatment window, and high incidence of systemic adverse reactions still limit the further clinical application of Cel. Here, aiming at effectively overcome those shortcomings of Cel to boost its beneficial effects for treating RA, we developed the leukosome (LEUKO) coated biomimetic nanoparticles (NPs) for the targeted delivery of Cel to arthritis injury area in RA. LEUKO were synthesized using membrane proteins purified from activated J774 macrophage. LEUKO and Cel-loaded LEUKO (Cel@LEUKO) were characterized using dynamic light scattering and transmission electron microscopy. Our results demonstrated that Cel@LEUKO can inhibit the inflammatory response of lipopolysaccharide (LPS) induced mouse monocyte macrophage leukemia cells (RAW264.7 cells) and human rheumatoid arthritis synovial fibroblasts (MH7A) cells through the inhibition of reactive oxygen species (ROS)-NF-κB pathway. In addition, research has shown that LEUKO effectively targets and transports Cel to the inflammatory site of RA, increased drug concentration in affected areas, reduced systemic toxicity of Cel, and reduced clinical symptoms, inflammatory infiltration, bone erosion, and serum inflammatory factors in collagen-induced arthritis (CIA) rats.

Unlocking the power of nanomedicine: Cell membrane-derived biomimetic cancer nanovaccines for cancer treatment

Over the past decades, nanomedicine researchers have dedicated their efforts to developing nanoscale platforms capable of more precisely delivering drug payloads to attack tumors. Cancer nanovaccines are exhibiting a distinctive capability in inducing tumor-specific antitumor responses. Nevertheless, there remain numerous challenges that must be addressed for cancer nanovaccines to evoke sufficient therapeutic effects. Cell membrane-derived nanovaccines are an emerging class of cancer vaccines that comprise a synthetic nanoscale core camouflaged by naturally derived cell membranes. The specific cell membrane has a biomimetic nanoformulation with several distinctive abilities, such as immune evasion, enhanced biocompatibility, and tumor targeting, typically associated with a source cell. Here, we discuss the advancements of cell membrane-derived nanovaccines and how these vaccines are used for cancer therapeutics. Translational endeavors are currently in progress, and additional research is also necessary to effectively address crucial areas of demand, thereby facilitating the future successful translation of these emerging vaccine platforms.

Biomimetic proteolipid vesicles for reverting GPI deficiency in paroxysmal nocturnal hemoglobinuria

Nano-vesicular carriers are promising tissue-specific drug delivery platforms. Here, biomimetic proteolipid vesicles (BPLVs) were used for delivery of glycosylphosphatidylinositol (GPI)-anchored proteins to GPI deficient paroxysmal nocturnal hemoglobinuria (PNH) cells. BPLVs were assembled as single unilamellar monodispersed (polydispersity index, 0.1) negatively charged (ζ-potential, -28.6 ± 5.6 mV) system using microfluidic technique equipped with Y-shaped chip. GPI-anchored and not-GPI proteins on BPLV surface were detected by flow cytometry. Peripheral blood mononuclear cells (PBMCs) from healthy and PNH subjects were treated with BPLVs (final concentration, 0.5 mg/mL), and cells displayed an excellent protein uptake, documented by flow cytometry immunophenotyping and confocal microscopy. BPLV-treated cells stressed with complement components showed an increased resistance to complement-mediated lysis, both healthy and PNH PBMCs. In conclusion, BPLVs could be effective nanocarriers for protein transfer to targeted cells to revert protein deficiency, like in PNH disease. However, further in vivo studies are required to validate our preclinical in vitro results.

Microfluidic Platforms for Real-Time In Situ Monitoring of Biomarkers for Cellular Processes

Cellular processes are mechanisms carried out at the cellular level that are aimed at guaranteeing the stability of the organism they comprise. The investigation of cellular processes is key to understanding cell fate, understanding pathogenic mechanisms, and developing new therapeutic technologies. Microfluidic platforms are thought to be the most powerful tools among all methodologies for investigating cellular processes because they can integrate almost all types of the existing intracellular and extracellular biomarker-sensing methods and observation approaches for cell behavior, combined with precisely controlled cell culture, manipulation, stimulation, and analysis. Most importantly, microfluidic platforms can realize real-time in situ detection of secreted proteins, exosomes, and other biomarkers produced during cell physiological processes, thereby providing the possibility to draw the whole picture for a cellular process. Owing to their advantages of high throughput, low sample consumption, and precise cell control, microfluidic platforms with real-time in situ monitoring characteristics are widely being used in cell analysis, disease diagnosis, pharmaceutical research, and biological production. This review focuses on the basic concepts, recent progress, and application prospects of microfluidic platforms for real-time in situ monitoring of biomarkers in cellular processes.

Red blood cell-derived materials for cancer therapy: Construction, distribution, and applications

Cancer has become an increasingly important public health issue owing to its high morbidity and mortality rates. Although traditional treatment methods are relatively effective, they have limitations such as highly toxic side effects, easy drug resistance, and high individual variability. Meanwhile, emerging therapies remain limited, and their actual anti-tumor effects need to be improved. Nanotechnology has received considerable attention for its development and application. In particular, artificial nanocarriers have emerged as a crucial approach for tumor therapy. However, certain deficiencies persist, including immunogenicity, permeability, targeting, and biocompatibility. The application of erythrocyte-derived materials will help overcome the above problems and enhance therapeutic effects. Erythrocyte-derived materials can be acquired via the application of physical and chemical techniques from natural erythrocyte membranes, or through the integration of these membranes with synthetic inner core materials using cell membrane biomimetic technology. Their natural properties such as biocompatibility and long circulation time make them an ideal choice for drug delivery or nanoparticle biocoating. Thus, red blood cell-derived materials are widely used in the field of biomedicine. However, further studies are required to evaluate their efficacy, in vivo metabolism, preparation, design, and clinical translation. Based on the latest research reports, this review summarizes the biology, synthesis, characteristics, and distribution of red blood cell-derived materials. Furthermore, we provide a reference for further research and clinical transformation by comprehensively discussing the applications and technical challenges faced by red blood cell-derived materials in the treatment of malignant tumors.

Microfluidic development and biological evaluation of targeted therapy-loaded biomimetic nano system to improve the metastatic melanoma treatment

Optimizing current therapies is among next steps in metastatic melanoma (MM) treatment landscape. The innovation of this study is the design of production process by microfluidics of cell membrane (CM)-modified nanoparticles (NPs), as an emerging biomimetic platform that allows for reduced immune clearance, long blood circulation time and improved specific tumor targeting. To achieve melanoma selectivity, direct membrane fusion between synthetic liposomes and CMs extracted from MM cell line was performed by microfluidic sonication approach, then the hybrid liposomes were loaded with cobimetinib (Cob) or lenvatinib (Lenva) targeting agents and challenged against MM cell lines and liver cancer cell line to evaluate homotypic targeting and antitumor efficacy. Characterization studies demonstrated the effective fusion of CM with liposome and the high encapsulation efficiency of both drugs, showing the proficiency of microfluidic-based production. By studying the targeting of melanoma cells by hybrid liposomes versus liposomes, we found that both NPs entered cells through endocytosis, whereas the former showed higher selectivity for MM cells from which CM was extracted, with 8-fold higher cellular uptake than liposomes. Hybrid liposome formulation of Cob and Lenva reduced melanoma cells viability to a greater extent than liposomes and free drug and, notably, showed negligible toxicity as demonstrated by bona fide haemolysis test. The CM-modified NPs presented here have the potential to broaden the choice of therapeutic options in MM treatment.

Targeting Lewis X oligosaccharide-modified liposomes encapsulated with house dust mite allergen Der f 2 to dendritic cells inhibits Th2 immune response

Allergen-specific immunotherapy (AIT) is the only curative treatment for allergic diseases. However, the long desensitization phase and potentially dangerous allergic side effects limit its broad application. Therefore, safer and more effective vaccines are required. Targeting dendritic cells (DCs) with novel allergen conjugates is a promising strategy for AIT. In this study, a novel vaccine with a DC-targeting effect for AIT was constructed. Liposomes were used as vehicles, and a targeted nanovaccine (Lex-lip-Der f 2) was constructed by loading the recombinant group 2 allergen of Dermatophagoides farinae (Der f 2) and conjugating with the DC-SIGN ligand Lewis X. The effect of the vaccine on DCs and T cell responses and the safety of the vaccine were investigated in vitro. The results showed that the Lex-lip-Der f 2 vaccine was spherical, with size of approximately 128 nm. The protein-loading capacity of the vaccine was 0.106 ± 0.001 mg per mg liposome and protein was gradually released from the liposomes during the first 12 h. Lex-lip-Der f 2 was taken up more efficiently by DCs than non-targeted liposomes or free Der f 2. Besides, Lex-lip-Der f 2 significantly inhibited the release of IL-4, IL-6, and TNF-a from DCs. Accordingly, Der f 2-lip loaded DCs significantly decreased IL-4 levels in autologous naïve CD4+T cells. Moreover, Lex-lip-Der f 2-treated basophils showed lower activation levels. These results suggest that DC-SIGN targeting mediated by Lewis X could inhibit the Th2 cell response and improve vaccine safety, and may be a novel vaccination strategy.

Preparation of Uniform Nano Liposomes Using Focused Ultrasonic Technology

Liposomes are microspheres produced by placing phospholipids in aqueous solutions. Liposomes have the advantage of being able to encapsulate both hydrophilic and hydrophobic functional substances and are thus important mediators used in cosmetics and pharmaceuticals. It is important for liposomes to have small sizes, uniform particle size distribution, and long-term stability. Previously, liposomes have been prepared using a homo mixer, microfluidizer, and horn and bath types of sonicators. However, it is difficult to produce liposomes with small sizes and uniform particle size distribution using these methods. Therefore, we have developed a focused ultrasound method to produce nano-sized liposomes with better size control. In this study, the liposome solutions were prepared using the focused ultrasound method and conventional methods. The liposome solutions were characterized for their size distribution, stability, and morphology. Results showed that the liposome solution prepared using focused ultrasonic equipment had a uniform particle size distribution with an average size of 113.6 nm and a polydispersity index value of 0.124. Furthermore, the solution showed good stability in dynamic light scattering measurements for 4 d and Turbiscan measurements for 1 week.

Microfluidic approaches for producing lipid-based nanoparticles for drug delivery applications

The importance of drug delivery for disease treatment is supported by a vast literature and increasing ongoing clinical studies. Several categories of nano-based drug delivery systems have been considered in recent years, among which lipid-based nanomedicines, both artificial and cell-derived, remain the most approved. The best artificial systems in terms of biocompatibility and low toxicity are liposomes, as they are composed of phospholipids and cholesterol, the main components of cell membranes. Extracellular vesicles-biological nanoparticles released from cells-while resembling liposomes in size, shape, and structure, have a more complex composition with up to hundreds of different types of lipids, proteins, and carbohydrates in their membranes, as well as an internal cargo. Although nanoparticle technologies have revolutionized drug delivery by enabling passive and active targeting, increased stability, improved solubilization capacity, and reduced dose and adverse effects, the clinical translation remains challenging due to manufacturing limitations such as laborious and time-consuming procedures and high batch-to-batch variability. A sea change occurred when microfluidic strategies were employed, offering advantages in terms of precise particle handling, simplified workflows, higher sensitivity and specificity, and good reproducibility and stability over bulk methods. This review examines scientific advances in the microfluidics-mediated production of lipid-based nanoparticles for therapeutic applications. We will discuss the preparation of liposomes using both hydrodynamic focusing of microfluidic flow and mixing by herringbone and staggered baffle micromixers. Then, an overview on microfluidic approaches for producing extracellular vesicles and extracellular vesicles-mimetics for therapeutic applications will describe microfluidic extrusion, surface engineering, sonication, electroporation, nanoporation, and mixing. Finally, we will outline the challenges, opportunities, and future directions of microfluidic investigation of lipid-based nanoparticles in the clinic.

Current aspects of small extracellular vesicles in pain process and relief

Small extracellular vesicles (sEVs) have been identified as a noteworthy paracrine mechanism of intercellular communication in diagnosing and managing neurological disorders. Current research suggests that sEVs play a pivotal role in the pathological progression of pain, emphasizing their critical function in the pathological progression of pain in acute and chronic pain models. By facilitating the transfer of diverse molecules, such as proteins, nucleic acids, and metabolites, sEVs can modulate pain signaling transmission in both the central and peripheral nervous systems. Furthermore, the unique molecules conveyed by sEVs in pain disorders indicate their potential as diagnostic biomarkers. The application of sEVs derived from mesenchymal stem cells (MSCs) in regenerative pain medicine has emerged as a promising strategy for pain management. Moreover, modified sEVs have garnered considerable attention in the investigation of pathological processes and therapeutic interventions. This review presents a comprehensive overview of the current knowledge regarding the involvement of sEVs in pain pathogenesis and treatment. Nevertheless, additional research is imperative to facilitate their clinical implementation. Schematic diagram of sEVs in the biogenesis, signal transmission, diagnosis, and treatment of pain disorders. Small extracellular vesicles (sEVs) are secreted by multiple cells, loading with various biomolecules, such as miRNAs, transmembrane proteins, and amino acids. They selectively target other cells and regulating pain signal transmission. The composition of sEVs can serve as valuable biomarkers for pain diagnosis. In particular, mesenchymal stem cell-derived sEVs have shown promise as regenerative medicine for managing multiple pain disorders. Furthermore, by modifying the structure or contents of sEVs, they could potentially be used as a potent analgesic method.

A Sustained-Release Nanosystem with MRSA Biofilm-Dispersing and -Eradicating Abilities Accelerates Diabetic Ulcer Healing

Introduction

Drug-resistant bacterial infections and biofilm formation play important roles in the pathogenesis of diabetic refractory wounds. Tea tree oil (TTO) exhibits antimicrobial, antimycotic, and antiviral activities, especially against common clinically resistant strains, such as methicillin-resistant Staphylococcus aureus (MRSA), making it a potential natural antimicrobial for the treatment of acute and chronic wounds. However, TTO is insoluble in water, volatile, light-sensitive, and cytotoxic. While previous macroscopic studies have focused on sterilization with TTO, none have sought to alter its structure or combine it with other materials to achieve sustained release.

Methods

Electrospun TTO nanoliposomes (TTO-NLs), arranged linearly via high-pressure homogenization, could stabilize the structure and performance of TTO to achieve slow drug release. Herein, we established a composite nano-sustained release system, TTO-NL/polyvinyl alcohol/chitosan (TTO-NL@PCS), using high-voltage electrospinning.

Results

Compared with the control, TTO-NL@PCS exhibits higher concentrations of the active TTO drug components, terpinen-4-ol and 1,8-cineole. Owing to its increased stability and slow release, early exposure to TTO-NL@PCS increases the abundance of reactive oxygen species in vitro, ultimately causing the biofilm to disperse and completely killing MRSA without inducing cytotoxic effects to the host. Moreover, in BKS-Leprem2Cd479/Gpt mice with a whole-layer skin infection, untargeted metabolomics analysis of wound exudates reveals upregulated PGF2α/FP receptor signaling and interleukin (IL)-1β and IL-6 expression following application of the composite system. The composite also ameliorates the chemotaxis disorder in early treatment and attenuates the wound inflammatory response during the repair stage of diabetic inflammatory wounds, and upregulates VEGF expression in the wound bed.

Conclusion

TTO-NL@PCS demonstrates the remarkable potential for accelerating diabetic and MRSA-infected wound healing.

Exploring the Microfluidic Production of Biomimetic Hybrid Nanoparticles and Their Pharmaceutical Applications

Nanomedicines have made remarkable advances in recent years, addressing the limitations of traditional therapy and treatment methods. Due to their improved drug solubility, stability, precise delivery, and ability to target specific sites, nanoparticle-based drug delivery systems have emerged as highly promising solutions. The successful interaction of nanoparticles with biological systems, on the other hand, is dependent on their intentional surface engineering. As a result, biomimetic nanoparticles have been developed as novel drug carriers. In-depth knowledge of various biomimetic nanoparticles, their applications, and the methods used for their formulation, with emphasis on the microfluidic production technique, is provided in this review. Microfluidics has emerged as one of the most promising approaches for precise control, high reproducibility, scalability, waste reduction, and faster production times in the preparation of biomimetic nanoparticles. Significant advancements in personalized medicine can be achieved by harnessing the benefits of biomimetic nanoparticles and leveraging microfluidic technology, offering enhanced functionality and biocompatibility.

Recent Advances in Cell Membrane Coated-Nanoparticles as Drug Delivery Systems for Tackling Urological Diseases

Recent studies have revealed the functional roles of cell membrane coated-nanoparticles (CMNPs) in tackling urological diseases, including cancers, inflammation, and acute kidney injury. Cells are a fundamental part of pathology to regulate nearly all urological diseases, and, therefore, naturally derived cell membranes inherit the functional role to enhance the biopharmaceutical performance of their encapsulated nanoparticles on drug delivery. In this review, methods for CMNP synthesis and surface engineering are summarized. The application of different types of CMNPs for tackling urological diseases is updated, including cancer cell membrane, stem cell membrane, immune cell membrane, erythrocytes cell membranes, and extracellular vesicles, and their potential for clinical use is discussed.

Immunomodulatory biomimetic nanoparticles target articular cartilage trauma after systemic administration

Post-traumatic osteoarthritis (PTOA) is one of the leading causes of disability in developed countries and accounts for 12% of all osteoarthritis cases in the United States. After trauma, inflammatory cells (macrophages amongst others) are quickly recruited within the inflamed synovium and infiltrate the joint space, initiating dysregulation of cartilage tissue homeostasis. Current therapeutic strategies are ineffective, and PTOA remains an open clinical challenge. Here, the targeting potential of liposome-based nanoparticles (NPs) is evaluated in a PTOA mouse model, during the acute phase of inflammation, in both sexes. NPs are composed of biomimetic phospholipids or functionalized with macrophage membrane proteins. Intravenous administration of NPs in the acute phase of PTOA and advanced in vivo imaging techniques reveal preferential accumulation of NPs within the injured joint for up to 7 days post injury, in comparison to controls. Finally, imaging mass cytometry uncovers an extraordinary immunomodulatory effect of NPs that are capable of decreasing the amount of immune cells infiltrating the joint and conditioning their phenotype. Thus, biomimetic NPs could be a powerful theranostic tool for PTOA as their accumulation in injury sites allows their identification and they have an intrinsic immunomodulatory effect.

Advances in nanomaterial-based targeted drug delivery systems

Nanomaterial-based drug delivery systems (NBDDS) are widely used to improve the safety and therapeutic efficacy of encapsulated drugs due to their unique physicochemical and biological properties. By combining therapeutic drugs with nanoparticles using rational targeting pathways, nano-targeted delivery systems were created to overcome the main drawbacks of conventional drug treatment, including insufficient stability and solubility, lack of transmembrane transport, short circulation time, and undesirable toxic effects. Herein, we reviewed the recent developments in different targeting design strategies and therapeutic approaches employing various nanomaterial-based systems. We also discussed the challenges and perspectives of smart systems in precisely targeting different intravascular and extravascular diseases.

Tyrosine kinase inhibitor-loaded biomimetic nanoparticles as a treatment for osteosarcoma

Small-molecule tyrosine kinase inhibitors (TKIs) represent a potentially powerful approach to the treatment of osteosarcoma (OS). However, dose-limiting toxicity, therapeutic efficacy, and targeting specificity are significant barriers to the use of TKIs in the clinic. Notably among TKIs, ponatinib demonstrated potent anti-tumor activity; however, it received an FDA black box warning for potential side effects. We propose ponatinib-loaded biomimetic nanoparticles (NPs) to repurpose ponatinib as an efficient therapeutic option for OS. In this study, we demonstrate enhanced targeting ability and maintain potent ponatinib nano-therapeutic activity, while also reducing toxicity. In in vitro two- and three-dimensional models, we demonstrate that ponatinib-loaded biomimetic NPs maintain the efficacy of the free drug, while in vivo we show that they can improve tumor targeting, slow tumor growth, and reduce evidence of systemic toxicities. Though there is limited Pon encapsulation within NPs, this platform may improve current therapeutic approaches and reduce dosage-related side effects to achieve better clinical outcomes in OS patients.

Graphical Abstract

Biomimetic Nanovesicles—Sources, Design, Production Methods, and Applications

Despite all the progress in the field of liposomes and nanoparticles for applications as drug and gene delivery systems, the specific targeting and immune system escape capabilities of these systems are still limited. Biomimetic nanovesicles emerged as a strategy to overcome these and other limitations associated with synthetic carriers, such as short circulation time, cytotoxicity, and difficulty in crossing biological barriers, since many of the desirable abilities of drug delivery systems are innate characteristics of biological vesicles. Thus, the question arises: would biomimetic nanovesicles be responsible for addressing these advances? It is currently known that biomimetic nanovesicles (BNV) can combine the intrinsic advantages of natural materials with the well-known production methods and controllability of synthetic systems. Besides, the development of the biotechnology and nanotechnology fields has provided a better understanding of the functionalities of biological vesicles and the means for the design and production of biomimetic nanovesicles (BNV). Based on this, this work will focus on tracking the main research on biomimetic nanovesicles (BNV) applied as drug and gene delivery systems, and for vaccines applications. In addition, it will describe the different sources of natural vesicles, the technical perspectives on obtaining them, and the possibility of their hybridization with synthetic liposomes.

Stem cell membrane-coated abiotic nanomaterials for biomedical applications

Nanoscale materials have been extensively employed for diagnostic and therapeutic purposes. However, the developed nanosystems still suffer from some limitations, namely the rapid elimination by the immune system, lack of targeting to specific cells, and insufficient biocompatibility. Therefore, novel strategies based upon a biomimetic approach have received attention to improving the pharmacokinetics and safety profile of nanosystems. One promising strategy is the application of a biomimetic coating consisting of cell membranes derived from different cell types onto nanoparticle cores. Stem cells have been investigated to develop targeted nanodevices owing to their excellent intrinsic tissue-specific homing features, protecting them from the immune system to reach the sites of inflammation. This targeting ability is conferred by a surface repertoire of stem cell-associated biomolecules. Such nanoscopical materials offer sustained circulation and boosted drug accumulation at target sites, augmenting therapeutic efficacy and safety. Additionally, the coating of nanoparticles with cell membranes acts as a camouflage mechanism to increase their circulation time. The current review explores the particular features of stem cell membrane coating as multifunctional biomimetic surface functionalization agents to camouflage nanoparticle cores. Biomedical applications of engineered stem cell membrane-coated nanoparticles, challenges in clinical translation, and their future prospects are addressed.

Harnessing Protein Corona for Biomimetic Nanomedicine Design

Nanoparticles (NPs) are usually treated as multifunctional agents combining several therapeutical applications, like imaging and targeting delivery. However, clinical translation is still largely hindered by several factors, and the rapidly formed protein corona on the surface of NPs is one of them. The formation of protein corona is complicated and irreversible in the biological environment, and protein corona will redefine the “biological identity” of NPs, which will alter the following biological events and therapeutic efficacy. Current understanding of protein corona is still limited and incomplete, and in many cases, protein corona has adverse impacts on nanomedicine, for instance, losing targeting ability, activating the immune response, and rapid clearance. Due to the considerable role of protein corona in NPs’ biological fate, harnessing protein corona to achieve some therapeutic effects through various methods like biomimetic approaches is now treated as a promising way to meet the current challenges in nanomedicine such as poor pharmacokinetic properties, off-target effect, and immunogenicity. This review will first introduce the current understanding of protein corona and summarize the investigation process and technologies. Second, the strategies of harnessing protein corona with biomimetic approaches for nanomedicine design are reviewed. Finally, we discuss the challenges and future outlooks of biomimetic approaches to tune protein corona in nanomedicine.

Microfluidic Nanoparticles for Drug Delivery

Nanoparticles (NPs) have attracted tremendous interest in drug delivery in the past decades. Microfluidics offers a promising strategy for making NPs for drug delivery due to its capability in precisely controlling NP properties. The recent success of mRNA vaccines using microfluidics represents a big milestone for microfluidic NPs for pharmaceutical applications, and its rapid scaling up demonstrates the feasibility of using microfluidics for industrial-scale manufacturing. This article provides a critical review of recent progress in microfluidic NPs for drug delivery. First, the synthesis of organic NPs using microfluidics focusing on typical microfluidic methods and their applications in making popular and clinically relevant NPs, such as liposomes, lipid NPs, and polymer NPs, as well as their synthesis mechanisms are summarized. Then, the microfluidic synthesis of several representative inorganic NPs (e.g., silica, metal, metal oxide, and quantum dots), and hybrid NPs is discussed. Lastly, the applications of microfluidic NPs for various drug delivery applications are presented.

Research update on cell membrane camouflaged nanoparticles for cancer therapy

Cell membrane-camouflaged biomimetic functionalization of nanoparticles has emerged as a promising strategy for cancer theranostics. These cell membranes used for camouflaging are generally isolated from natural or engineered erythrocytes, neutrophils, macrophages, T lymphatic cells, stem cells, and cancer cells. The camouflaging strategy of coating nanoparticles with cell membranes allows for tumor homotypic targeting through self-recognition as source cells, immune evasion, and a prolonged blood circulation time, thereby improving the effective payload delivery and tumor therapy. More so, some engineered cell membranes with functionalized peptides, proteins and moieties on membrane surface can be transferred for therapy in the same time. In this review, we summarize the latest research on various types of cell membrane-camouflaged nanoparticles aimed at anti-cancer therapy, focusing on the biological advantages of different cell membranes, constitutions of nanoparticles, fabrication processes, key findings, potential therapies, and discuss the major challenges and future opportunities.

Recent advances in erythrocyte membrane-camouflaged nanoparticles for the delivery of anti-cancer therapeutics

INTRODUCTION

Red blood cell (or erythrocyte) membrane-camouflaged nanoparticles (RBC-NPs) not only have a superior circulation life and do not induce accelerated blood clearance, but also possess special functions, which offers great potential in cancer therapy.

AREAS COVERED

This review focuses on the recent advances of RBC-NPs for delivering various agents to treat cancers in light of their vital role in improving drug delivery. Meanwhile, the construction and in vivo behavior of RBC-NPs are discussed to provide an in-depth understanding of the basis of RBC-NPs for improved cancer drug delivery.

EXPERT OPINION

Although RBC-NPs are quite prospective in delivering anti-cancer therapeutics, they are still in their infancy stage and many challenges need to be overcome for successful translation into the clinic. The preparation and modification of RBC membranes, the optimization of coating methods, the scale-up production and the quality control of RBC-NPs, and the drug loading and release should be carefully considered in the clinical translation of RBC-NPs for cancer therapy.

Biomimetic Nanomaterials: Diversity, Technology, and Biomedical Applications

Biomimetic nanomaterials (BNMs) are functional materials containing nanoscale components and having structural and technological similarities to natural (biogenic) prototypes. Despite the fact that biomimetic approaches in materials technology have been used since the second half of the 20th century, BNMs are still at the forefront of materials science. This review considered a general classification of such nanomaterials according to the characteristic features of natural analogues that are reproduced in the preparation of BNMs, including biomimetic structure, biomimetic synthesis, and the inclusion of biogenic components. BNMs containing magnetic, metal, or metal oxide organic and ceramic structural elements (including their various combinations) were considered separately. The BNMs under consideration were analyzed according to the declared areas of application, which included tooth and bone reconstruction, magnetic and infrared hyperthermia, chemo- and immunotherapy, the development of new drugs for targeted therapy, antibacterial and anti-inflammatory therapy, and bioimaging. In conclusion, the authors’ point of view is given about the prospects for the development of this scientific area associated with the use of native, genetically modified, or completely artificial phospholipid membranes, which allow combining the physicochemical and biological properties of biogenic prototypes with high biocompatibility, economic availability, and scalability of fully synthetic nanomaterials.

Artificial stem cells mediated inflammation-tropic delivery of antiviral drugs for pneumonia treatment

Background

Cytomegalovirus (CMV) pneumonia is a major cause of morbidity and mortality in immunodeficiency individuals, including transplant recipients and Acquired Immune Deficiency Syndrome patients. Antiviral drugs ganciclovir (GCV) and phosphonoformate (PFA) are first-line agents for pneumonia caused by herpesvirus infection. However, the therapy suffers from various limitations such as low efficiency, drug resistance, toxicity, and lack of specificity.

Methods

The antiviral drugs GCV and PFA were loaded into the pH-responsive nanoparticles fabricated by poly(lactic-co-glycolic acid) (PLGA) and 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), and further coated with cell membranes derived from bone marrow mesenchymal stem cells to form artificial stem cells, namely MPDGP. We evaluated the viral suppression effects of MPDGP in vitro and in vivo.

Results

MPDGP showed significant inflammation tropism and efficient suppression of viral replication and virus infection-associated inflammation in the CMV-induced pneumonia model. The synergistic effects of the combination of viral DNA elongation inhibitor GCV and viral DNA polymerase inhibitor PFA on suppressing the inflammation efficiently.

Conclusion

The present study develops a novel therapeutic intervention using artificial stem cells to deliver antiviral drugs at inflammatory sites, which shows great potential for the targeted treatment of pneumonia. To our best knowledge, we are the first to fabricate this kind of artificial stem cell to deliver antiviral drugs for pneumonia treatment.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01547-x.

Transformation of Amphiphilic Antiviral Drugs into New Dimensional Nanovesicles Structures

Improved techniques were applied to formulate drugs into dimensional nanostructures, doped "nanovesicles". These nanovesicles are solely composed of self-assembled amphiphilic antiviral agents used for the treatment of viral infections caused by flaviviruses, such as Zika virus. Studies were done to evaluate the effectiveness of the syntheses, formation, and performance under different experimental conditions, and behavior of the drug nanovesicles in vitro and in vivo. These studies demonstrated that assembling the hydrophobic antiviral drug molecules into nanodrugs is a successful technique for the delivery of the therapeutic agents, otherwise difficult to be supplied. Our studies confirmed that this nanodrug preserved and, in many cases, enhanced the embedded cellular activity of the parental free drug molecules, both in vitro and in vivo. This proposed formulation is highly important as it addresses the issue of insolubility and low bioavailabiity of a wide range of highly potent pharmaceutical drugs-not limited to a specific class of antiviral drugs-that are of high demand for the treatment of medical conditions and emerging pathogens.

Optimization of Biomimetic, Leukocyte-Mimicking Nanovesicles for Drug Delivery Against Colorectal Cancer Using a Design of Experiment Approach

The development of biomimetic nanoparticles (NPs) has revolutionized the concept of nanomedicine by offering a completely new set of biocompatible materials to formulate innovative drug delivery systems capable of imitating the behavior of cells. Specifically, the use of leukocyte-derived membrane proteins to functionalize nanovesicles (leukosomes) can enable their long circulation and target the inflamed endothelium present in many inflammatory pathologies and tumors, making them a promising and versatile drug delivery system. However, these studies did not elucidate the critical experimental parameters involved in leukosomes formulation. In the present study, we approached the preparation of leukosomes using a design of experiment (DoE) method to better understand the influence of experimental parameters on leukosomes features such as size, size distribution, and protein loading. We also validated this formulation technologically and tested its behavior in in vitro colorectal cancer (CRC) models, including CRC patient-derived tumor organoids (PDOs). We demonstrated leukosomes biocompatibility, endothelium adhesion capability, and tumor target in three-dimensional (3D) settings using CRC cell lines. Overall, our study offers a novel conceptual framework for biomimetic NPs using a DoE strategy and consolidates the high therapeutic potential of leukosomes as a viable drug delivery system for anti-inflammatory and antineoplastic applications.

COVID-19 inflammation and implications in drug delivery

Growing evidence indicates that hyperinflammatory syndrome and cytokine storm observed in COVID-19 severe cases are narrowly associated with the disease's poor prognosis. Therefore, targeting the inflammatory pathways seems to be a rational therapeutic strategy against COVID-19. Many anti-inflammatory agents have been proposed; however, most of them suffer from poor bioavailability, instability, short half-life, and undesirable biodistribution resulting in off-target effects. From a pharmaceutical standpoint, the implication of COVID-19 inflammation can be exploited as a therapeutic target and/or a targeting strategy against the pandemic. First, the drug delivery systems can be harnessed to improve the properties of anti-inflammatory agents and deliver them safely and efficiently to their therapeutic targets. Second, the drug carriers can be tailored to develop smart delivery systems able to respond to the microenvironmental stimuli to release the anti-COVID-19 therapeutics in a selective and specific manner. More interestingly, some biosystems can simultaneously repress the hyperinflammation due to their inherent anti-inflammatory potency and endow their drug cargo with a selective delivery to the injured sites.

Novel microfluidic swirl mixers for scalable formulation of curcumin loaded liposomes for cancer therapy

Liposomes have been widely used in nanomedicine for the delivery of hydrophobic and hydrophilic anticancer agents. The most common applications of these formulations are vaccines and anticancer formulations (e.g., mRNA, small molecule drugs). However, large-scale production with precise control of size and size distribution of the lipid-based drug delivery systems (DDSs) is one of the major challenges in the pharmaceutical industry. In this study, we used newly designed microfluidic swirl mixers with simple 3D mixing chamber structures to prepare liposomes at a larger scale (up to 320 mL/min or 20 L/h) than the commercially available devices. This design demonstrated high productivity and better control of liposome size and polydispersity index (PDI) than conventional liposome preparation methods. The microfluidic swirl mixer devices were used to produce curcumin-loaded liposomes under different processing conditions which were later characterized and studied in vitro to evaluate their efficiency as DDSs. The obtained results demonstrated that the liposomes can effectively deliver curcumin into cancer cells. Therefore, the microfluidic swirl mixers are promising devices for reproducible and scalable manufacturing of DDSs.

Latest Advances in Biomimetic Cell Membrane-Coated and Membrane-Derived Nanovectors for Biomedical Applications

In the last decades, many nanovectors were developed for different diagnostic or therapeutic purposes. However, most nanosystems have been designed using a “bottom-up” approach, in which the basic components of the nanovector become assembled to achieve complex and specific behaviors. Despite the fine control of formulative conditions, the complexity of these systems often results cumbersome and difficult to scale-up. Recently, biomimetic materials emerged as a complementary or alternative design approach through a “top-down strategy”, using cell-derived materials as building blocks to formulate innovative nanovectors. The use of cell membranes as nanoparticle coatings endows nanomaterials with the biological identity and some of the functions of the cells they are derived from. In this review, we discuss some of the latest examples of membrane coated and membrane-derived biomimetic nanomaterials and underline the common general functions offered by the biomaterials used. From these examples, we suggest a systematic classification of these biomimetic materials based on their biological sources and formulation techniques, with their respective advantages and disadvantages, and summarize the current technologies used for membranes isolation and integration on nanovectors. We also discuss some current technical limitations and hint to future direction of the improvement for biomimetics.

Engineering extracellular vesicles for Alzheimer's disease: An emerging cell-free approach for earlier diagnosis and treatment

Alzheimer's disease (AD) is a debilitating neurodegenerative disorder affecting over five million people globally and has no established cure. Current AD-related treatments only alleviate cognitive and behavioral symptoms and do not address disease onset or progression, underlining the unmet need to create an effective, innovative AD therapeutic. Extracellular vesicles (EVs) have emerged as a new class of nanotherapeutics. These secreted, lipid-bound cellular signaling carriers show promise for potential clinical applications for neurodegenerative diseases like AD. Additionally, analyzing contents and characteristics of patient-derived EVs may address the unmet need for earlier AD diagnostic techniques, informing physicians of altered genetic expression or cellular communications specific to healthy and diseased physiological states. There are numerous recent advances in regenerative medicine using EVs and include bioengineering perspectives to modify EVs, target glial cells in neurodegenerative diseases like AD, and potentially use EVs to diagnose and treat AD earlier. This article is categorized under: Neurological Diseases > Biomedical Engineering Neurological Diseases > Molecular and Cellular Physiology Neurological Diseases > Stem Cells and Development.

Engineered Cell Membrane-Derived Nanocarriers: The Enhanced Delivery System for Therapeutic Applications

There has been a rapid development of biomimetic platforms using cell membranes as nanocarriers to camouflage nanoparticles for enhancing bio-interfacial capabilities. Various sources of cell membranes have been explored for natural functions such as circulation and targeting effect. Biomedical applications of cell membranes-based delivery systems are expanding from cancer to multiple diseases. However, the natural properties of cell membranes are still far from achieving desired functions and effects as a nanocarrier platform for various diseases. To obtain multi-functionality and multitasking in complex biological systems, various functionalized modifications of cell membranes are being developed based on physical, chemical, and biological methods. Notably, many research opportunities have been initiated at the interface of multi-technologies and cell membranes, opening a promising frontier in therapeutic applications. Herein, the current exploration of natural cell membrane functionality, the design principles for engineered cell membrane-based delivery systems, and the disease applications are reviewed, with a special focus on the emerging strategies in engineering approaches.

Nanoparticle protein corona evolution: from biological impact to biomarker discovery

Nanoparticles exposed to biological fluids such as blood, quickly interact with their surrounding milieu resulting in a biological coating that results in large part as a function of the physicochemical properties of the nanomaterial. The large nanoparticle surface area-to-volume ratio further augments binding of biological molecules and the resulting biomolecular or protein corona, once thought of as problematic biofouling, is now viewed as a rich source of biological information that can guide the development of nanomedicines. This review gives an overview of the utility of the protein corona in proteomic profiling and discusses how a better understanding of nano-bio interactions can accelerate the clinical translation of nanomedicines and facilitate the identification of disease-specific biomarkers. With the FDA requirement of the protein corona analysis of nanoparticles in place, it is envisaged that analyzing the protein corona of nanoparticles on a case-by-case basis can provide highly valuable nano-bio interface information that can aid and improve their clinical translation.

Extracellular Vesicle-Based Hybrid Systems for Advanced Drug Delivery

The continuous technological advancement of nanomedicine has enabled the development of novel vehicles for the effective delivery of therapeutic substances. Synthetic drug delivery systems are nano-sized carriers made from various materials that can be designed to deliver therapeutic cargoes to cells or tissues. However, rapid clearance by the immune system and the poor targeting profile of synthetic drug delivery systems are examples of the pressing obstacles faced in nanomedicine, which have directed the field toward the development of alternative strategies. Extracellular vesicles (EVs) are nanoscale particles enclosed by a protein-rich lipid bilayer; they are released by cells and are considered to be important mediators of intercellular communication. Owing to their natural composition, EVs have been suggested to exhibit good biocompatibility and to possess homing properties to specific cell types. Combining EVs with synthetic nanoparticles by defined hybridization steps gives rise to a novel potential drug delivery tool, i.e., EV-based hybrid systems. These novel therapeutic vehicles exhibit potential advantageous features as compared to synthetic drug delivery systems such as enhanced cellular uptake and cargo delivery, immuno-evasive properties, capability of crossing biological barriers, and tissue targeting profile. Here, we provide an overview of the various strategies practiced to produce EV-based hybrid systems and elucidate those advantageous features obtained by synthetic drug delivery systems upon hybridization with EVs.

Advanced Microfluidic Technologies for Lipid Nano-Microsystems from Synthesis to Biological Application

Microfluidics is an emerging technology that can be employed as a powerful tool for designing lipid nano-microsized structures for biological applications. Those lipid structures can be used as carrying vehicles for a wide range of drugs and genetic materials. Microfluidic technology also allows the design of sustainable processes with less financial demand, while it can be scaled up using parallelization to increase production. From this perspective, this article reviews the recent advances in the synthesis of lipid-based nanostructures through microfluidics (liposomes, lipoplexes, lipid nanoparticles, core-shell nanoparticles, and biomimetic nanovesicles). Besides that, this review describes the recent microfluidic approaches to produce lipid micro-sized structures as giant unilamellar vesicles. New strategies are also described for the controlled release of the lipid payloads using microgels and droplet-based microfluidics. To address the importance of microfluidics for lipid-nanoparticle screening, an overview of how microfluidic systems can be used to mimic the cellular environment is also presented. Future trends and perspectives in designing novel nano and micro scales are also discussed herein.

Nanoplateletsomes restrain metastatic tumor formation through decoy and active targeting in a preclinical mouse model

Platelets buoy up cancer metastasis via arresting cancer cells, enhancing their adhesion, and facilitating their extravasation through the vasculature. When deprived of intracellular and granular contents, platelet decoys could prevent metastatic tumor formation. Inspired by these, we developed nanoplatesomes by fusing platelet membranes with lipid membranes (P-Lipo) to restrain metastatic tumor formation more efficiently. It was shown nanoplateletsomes bound with circulating tumor cells (CTC) efficiently, interfered with CTC arrest by vessel endothelial cells, CTC extravasation through endothelial layers, and epithelial-mesenchymal transition of tumor cells as nanodecoys. More importantly, in the mouse breast tumor metastasis model, nanoplateletsomes could decrease CTC survival in the blood and counteract metastatic tumor growth efficiently by inhibiting the inflammation and suppressing CTC escape. Therefore, nanoplatelesomes might usher in a new avenue to suppress lung metastasis.

LDL-Based Lipid Nanoparticle Derived for Blood Plasma Accumulates Preferentially in Atherosclerotic Plaque

Apolipoprotein-based drug delivery is a promising approach to develop safe nanoparticles capable of targeted drug delivery for various diseases. In this work, we have synthesized a lipid-based nanoparticle (NPs) that we have called “Aposomes” presenting native apolipoprotein B-100 (apoB-100), the primary protein present in Low-Density Lipoproteins (LDL) on its surface. The aposomes were synthesized from LDL isolated from blood plasma using a microfluidic approach. The synthesized aposomes had a diameter of 91 ± 4 nm and a neutral surface charge of 0.7 mV ± mV. Protein analysis using western blot and flow cytometry confirmed the presence of apoB-100 on the nanoparticle’s surface. Furthermore, Aposomes retained liposomes’ drug loading capabilities, demonstrating a prolonged release curve with ∼80% cargo release at 4 hours. Considering the natural tropism of LDL towards the atherosclerotic plaques, we evaluated the biological properties of aposomes in a mouse model of advanced atherosclerosis. We observed a ∼20-fold increase in targeting of plaques when comparing aposomes to control liposomes. Additionally, aposomes presented a favorable biocompatibility profile that showed no deviation from typical values in liver toxicity markers (i.e., LDH, ALT, AST, Cholesterol). The results of this study demonstrate the possibilities of using apolipoprotein-based approaches to create nanoparticles with active targeting capabilities and could be the basis for future cardiovascular therapies.

Label-Free Isolation of Exosomes Using Microfluidic Technologies

Exosomes are cell-derived structures packaged with lipids, proteins, and nucleic acids. They exist in diverse bodily fluids and are involved in physiological and pathological processes. Although their potential for clinical application as diagnostic and therapeutic tools has been revealed, a huge bottleneck impeding the development of applications in the rapidly burgeoning field of exosome research is an inability to efficiently isolate pure exosomes from other unwanted components present in bodily fluids. To date, several approaches have been proposed and investigated for exosome separation, with the leading candidate being microfluidic technology due to its relative simplicity, cost-effectiveness, precise and fast processing at the microscale, and amenability to automation. Notably, avoiding the need for exosome labeling represents a significant advance in terms of process simplicity, time, and cost as well as protecting the biological activities of exosomes. Despite the exciting progress in microfluidic strategies for exosome isolation and the countless benefits of label-free approaches for clinical applications, current microfluidic platforms for isolation of exosomes are still facing a series of problems and challenges that prevent their use for clinical sample processing. This review focuses on the recent microfluidic platforms developed for label-free isolation of exosomes including those based on sieving, deterministic lateral displacement, field flow, and pinched flow fractionation as well as viscoelastic, acoustic, inertial, electrical, and centrifugal forces. Further, we discuss advantages and disadvantages of these strategies with highlights of current challenges and outlook of label-free microfluidics toward the clinical utility of exosomes.

Humanized Biomimetic Nanovesicles for Neuron Targeting

Nanovesicles (NVs) are emerging as innovative, theranostic tools for cargo delivery. Recently, surface engineering of NVs with membrane proteins from specific cell types has been shown to improve the biocompatibility of NVs and enable the integration of functional attributes. However, this type of biomimetic approach has not yet been explored using human neural cells for applications within the nervous system. Here, this paper optimizes and validates the scalable and reproducible production of two types of neuron-targeting NVs, each with a distinct lipid formulation backbone suited to potential therapeutic cargo, by integrating membrane proteins that are unbiasedly sourced from human pluripotent stem-cell-derived neurons. The results establish that both endogenous and genetically engineered cell-derived proteins effectively transfer to NVs without disruption of their physicochemical properties. NVs with neuron-derived membrane proteins exhibit enhanced neuronal association and uptake compared to bare NVs. Viability of 3D neural sphere cultures is not disrupted by treatment, which verifies the utility of organoid-based approaches as NV testing platforms. Finally, these results confirm cellular association and uptake of the biomimetic humanized NVs to neurons within rodent cranial nerves. In summary, the customizable NVs reported here enable next-generation functionalized theranostics aimed to promote neuroregeneration.

Cell membrane coating integrity affects the internalization mechanism of biomimetic nanoparticles

Cell membrane coated nanoparticles (NPs) have recently been recognized as attractive nanomedical tools because of their unique properties such as immune escape, long blood circulation time, specific molecular recognition and cell targeting. However, the integrity of the cell membrane coating on NPs, a key metrics related to the quality of these biomimetic-systems and their resulting biomedical function, has remained largely unexplored. Here, we report a fluorescence quenching assay to probe the integrity of cell membrane coating. In contradiction to the common assumption of perfect coating, we uncover that up to 90% of the biomimetic NPs are only partially coated. Using in vitro homologous targeting studies, we demonstrate that partially coated NPs could still be internalized by the target cells. By combining molecular simulations with experimental analysis, we further identify an endocytic entry mechanism for these NPs. We unravel that NPs with a high coating degree (≥50%) enter the cells individually, whereas the NPs with a low coating degree (<50%) need to aggregate together before internalization. This quantitative method and the fundamental understanding of how cell membrane coated NPs enter the cells will enhance the rational designing of biomimetic nanosystems and pave the way for more effective cancer nanomedicine.

Epigenetic inhibition assisted chemotherapeutic treatment of lung cancer based on artificial exosomes

We adopted a novel strategy by combining histone deacetylase (HDAC) inhibitors with traditional chemotherapeutics to treat solid tumors. However, chemotherapeutics often have a narrow therapeutic index and need multiple administrations with undesired side effects that lead to the intolerance. To reduce the non-specificity of chemotherapeutics, targeted therapy was introduced to restrict such agents in the tumor with minimum effects on other tissues. We developed bioinspired artificial exosomes (AE), which enabled to deliver chemotherapeutics to the tumors effectively after systemic administration. AE were produced by incorporating membrane proteins from cancer cells into phospholipid liposomes that mimicked the plasma membrane. The synthesized AE were used for the delivery of broad-spectrum chemotherapeutic doxorubicin (DOX) and vorinostat (SAHA), an epigenetic inhibitor. The combination of DOX and SAHA showed synergistic effects on suppressing non-small cell lung cancer cells and xenograft tumors without apparent adverse effects. AE facilitated the delivery of drugs to tumor tissue and extended the retention time of drugs within tumors. Taken together, these studies suggest that the bioengineered artificial exosomes may serve as novel delivery strategy for chemotherapeutics to treat non-small cell lung cancer.

Biomimetic Nanoparticles as a Theranostic Tool for Traumatic Brain Injury

Traumatic brain injury (TBI) triggers both central and peripheral inflammatory responses. Existing pharmacological drugs are unable to effectively and quickly target the brain inflamed regions, setting up a major roadblock towards effective brain trauma treatments. Nanoparticles (NPs) have been used in multiple diseases as drug delivery tools with remarkable success due to their rapid diffusion and specificity in the target organ. Here, leukocyte-based biomimetic NPs are fabricated as a theranostic tool to directly access inflamed regions in a TBI mouse model. This NP systemic delivery is visualized using advanced in vivo imaging techniques, including intravital microscopy and in vivo imaging system. The results demonstrate selective targeting of NPs to the injured brain and increased NPs accumulation among the peripheral organs 24 h after TBI. Interestingly, increased microglial proliferation, decreased macrophage infiltration, and reduced brain lesion following the NPs treatments compared to sham vehicle-treated mice are also found. In summary, the results suggest that NPs represent a promising future theranostic tool for TBI treatment.

Cell membrane cloaked nanomedicines for bio-imaging and immunotherapy of cancer: Improved pharmacokinetics, cell internalization and anticancer efficacy

Despite enormous advancements in the field of oncology, the innocuous and effectual treatment of various types of malignancies remained a colossal challenge. The conventional modalities such as chemotherapy, radiotherapy, and surgery have been remained the most viable options for cancer treatment, but lacking of target-specificity, optimum safety and efficacy, and pharmacokinetic disparities are their impliable shortcomings. Though, in recent decades, numerous encroachments in the field of onco-targeted drug delivery have been adapted but several limitations (i.e., short plasma half-life, early clearance by reticuloendothelial system, immunogenicity, inadequate internalization and localization into the onco-tissues, chemoresistance, and deficient therapeutic efficacy) associated with these onco-targeted delivery systems limits their clinical viability. To abolish the aforementioned inadequacies, a promising approach has been emerged in which stealthing of synthetic nanocarriers has been attained by cloaking them into the natural cell membranes. These biomimetic nanomedicines not only retain characteristics features of the synthetic nanocarriers but also inherit the cell-membrane intrinsic functionalities. In this review, we have summarized preparation methods, mechanism of cloaking, and pharmaceutical and therapeutic superiority of cell-membrane camouflaged nanomedicines in improving the bio-imaging and immunotherapy against various types of malignancies. These pliable adaptations have revolutionized the current drug delivery strategies by optimizing the plasma circulation time, improving the permeation into the cancerous microenvironment, escaping the immune evasion and rapid clearance from the systemic circulation, minimizing the immunogenicity, and enabling the cell-cell communication via cell membrane markers of biomimetic nanomedicines. Moreover, the preeminence of cell-membrane cloaked nanomedicines in improving the bio-imaging and theranostic applications, alone or in combination with phototherapy or radiotherapy, have also been pondered.

Enhancing Inflammation Targeting Using Tunable Leukocyte-Based Biomimetic Nanoparticles

Biomimetic nanoparticles aim to effectively emulate the behavior of either cells or exosomes. Leukocyte-based biomimetic nanoparticles, for instance, incorporate cell membrane proteins to transfer the natural tropism of leukocytes to the final delivery platform. However, tuning the protein integration can affect the in vivo behavior of these nanoparticles and alter their efficacy. Here we show that, while increasing the protein:lipid ratio to a maximum of 1:20 (w/w) maintained the nanoparticle's structural properties, increasing protein content resulted in improved targeting of inflamed endothelium in two different animal models. Our combined use of a microfluidic, bottom-up approach and tuning of a key synthesis parameter enabled the synthesis of reproducible, enhanced biomimetic nanoparticles that have the potential to improve the treatment of inflammatory-based conditions through targeted nanodelivery.

Topical Unsaturated Fatty Acid Vesicles Improve Antioxidant Activity of Ammonium Glycyrrhizinate

Linoleic and oleic acids are natural unsaturated fatty acids involved in several biological processes and recently studied as structural components of innovative nanovesicles. The use of natural components in the pharmaceutical field is receiving growing attention from the scientific world. The aim of this research work is to design, to perform physico-chemical characterization and in vitro/in vivo studies of unsaturated fatty acids vesicles containing ammonium glycyrrhizinate, obtaining a new topical drug delivery system. The chosen active substance is well known as an anti-inflammatory compound, but its antioxidant activity is also noteworthy. In this way, the obtained nanocarriers are totally natural vesicles and they have shown to have suitable physico-chemical features for topical administration. Moreover, the proposed nanocarriers have proven their ability to improve the in vitro percutaneous permeation and antioxidant activity of ammonium glycyrrhizinate on human keratinocytes (NCTC 2544 cells). In vivo studies, carried out on human volunteers, have demonstrated the biocompatibility of unsaturated fatty acid vesicles toward skin tissue, indicating a possible clinical application of unsaturated fatty acid vesicles for the treatment of topical diseases.

Biomimetic bacterial and viral-based nanovesicles for drug delivery, theranostics, and vaccine applications

Smart nanocarriers obtained from bacteria and viruses offer excellent biomimetic properties which has led to significant research into the creation of advanced biomimetic materials. Their versatile biomimicry has application as biosensors, biomedical scaffolds, immobilization, diagnostics, and targeted or personalized treatments. The inherent natural traits of biomimetic and bioinspired bacteria- and virus-derived nanovesicles show potential for their use in clinical vaccines and novel therapeutic drug delivery systems. The past few decades have seen significant progress in the bioengineering of bacteria and viruses to manipulate and enhance their therapeutic benefits. From a pharmaceutical perspective, biomimetics enable the safe integration of naturally occurring bacteria and virus particles to achieve high, stable rates of cellular transfection/infection and prolonged circulation times. In addition, biomimetic technologies can overcome safety concerns associated with live-attenuated and inactivated whole bacteria or viruses. In this review, we provide an update on the utilization of bacterial and viral particles as drug delivery systems, theranostic carriers, and vaccine/immunomodulation modalities.

Prunus spinosa Extract Loaded in Biomimetic Nanoparticles Evokes In Vitro Anti-Inflammatory and Wound Healing Activities

Prunus spinosa fruits (PSF) contain different phenolic compounds showing antioxidant and anti-inflammatory activities. Innovative drug delivery systems such as biomimetic nanoparticles could improve the activity of PSF extract by promoting (i) the protection of payload into the lipidic bilayer, (ii) increased accumulation to the diseased tissue due to specific targeting properties, (iii) improved biocompatibility, (iv) low toxicity and increased bioavailability. Using membrane proteins extracted from human monocyte cell line THP-1 cells and a mixture of phospholipids, we formulated two types of PSF-extract-loaded biomimetic vesicles differing from each other for the presence of either 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DOPG). The biological activity of free extract (PSF), compared to both types of extract-loaded vesicles (PSF-DOPCs and PSF-DOPGs) and empty vesicles (DOPCs and DOPGs), was evaluated in vitro on HUVEC cells. PSF-DOPCs showed preferential incorporation of the extract. When enriched into the nanovesicles, the extract showed a significantly increased anti-inflammatory activity, and a pronounced wound-healing effect (with PSF-DOPCs more efficient than PSF-DOPG) compared to free PSF. This innovative drug delivery system, combining nutraceutical active ingredients into a biomimetic formulation, represents a possible adjuvant therapy for the treatment of wound healing. This nanoplatform could be useful for the encapsulation/enrichment of other nutraceutical products with short stability and low bioavailability.

Biomimetic Nanoparticles Potentiate the Anti-Inflammatory Properties of Dexamethasone and Reduce the Cytokine Storm Syndrome: An Additional Weapon against COVID-19?

Recent studies on coronavirus infectious disease 2019 (COVID-19) pathophysiology indicated the cytokine release syndrome induced by the virus as the main cause of mortality. Patients with severe COVID-19 infection present a systemic hyper inflammation that can lead to lung and multi-organ injuries. Among the most recent treatments, corticosteroids have been identified to be effective in mitigating these catastrophic effects. Our group has recently developed leukocyte-derived nanovesicles, termed leukosomes, able to target in vivo the inflamed vasculature associated with pathological conditions including cancer, cardiovascular diseases, and sepsis. Herein, to gain insights on the anti-inflammatory properties of leukosomes, we investigated their ability to reduce uncontrolled inflammation in a lethal model of lipopolysaccharide (LPS)-induced endotoxemia, recapitulating the cytokine storm syndrome observed in COVID-19 infection after encapsulating dexamethasone. Treated animals showed a significant survival advantage and an improved immune response resolution, as demonstrated by a cytokine array analysis of pro- and anti-inflammatory cytokines, chemokines, and other immune-relevant markers. Our results showed that leukosomes enhance the therapeutic activity of dexamethasone and better control the inflammatory response compared to the free drug. Such an approach could be useful for the development of personalized therapies in the treatment of hyperinflammation related to infectious diseases, including the ones caused by COVID-19.