Biomimetic strategies for targeted nanoparticle delivery

Application of biomimetic nanovaccines in cancer immunotherapy: A useful strategy to help combat immunotherapy resistance

Breakthroughs in actual clinical applications have begun through vaccine-based cancer immunotherapy, which uses the body's immune system, both humoral and cellular, to attack malignant cells and fight diseases. However, conventional vaccine approaches still face multiple challenges eliciting effective antigen-specific immune responses, resulting in immunotherapy resistance. In recent years, biomimetic nanovaccines have emerged as a promising alternative to conventional vaccine approaches by incorporating the natural structure of various biological entities, such as cells, viruses, and bacteria. Biomimetic nanovaccines offer the benefit of targeted antigen-presenting cell (APC) delivery, improved antigen/adjuvant loading, and biocompatibility, thereby improving the sensitivity of immunotherapy. This review presents a comprehensive overview of several kinds of biomimetic nanovaccines in anticancer immune response, including cell membrane-coated nanovaccines, self-assembling protein-based nanovaccines, extracellular vesicle-based nanovaccines, natural ligand-modified nanovaccines, artificial antigen-presenting cells-based nanovaccines and liposome-based nanovaccines. We also discuss the perspectives and challenges associated with the clinical translation of emerging biomimetic nanovaccine platforms for sensitizing cancer cells to immunotherapy.

Effect of Polymer and Cell Membrane Coatings on Theranostic Applications of Nanoparticles: A Review

The recent decade has witnessed a remarkable surge in the field of nanoparticles, from their synthesis, characterization, and functionalization to diverse applications. At the nanoscale, these particles exhibit distinct physicochemical properties compared to their bulk counterparts, enabling a multitude of applications spanning energy, catalysis, environmental remediation, biomedicine, and beyond. This review focuses on specific nanoparticle categories, including magnetic, gold, silver, and quantum dots (QDs), as well as hybrid variants, specifically tailored for biomedical applications. A comprehensive review and comparison of prevalent chemical, physical, and biological synthesis methods are presented. To enhance biocompatibility and colloidal stability, and facilitate surface modification and cargo/agent loading, nanoparticle surfaces are coated with different synthetic polymers and very recently, cell membrane coatings. The utilization of polymer- or cell membrane-coated nanoparticles opens a wide variety of biomedical applications such as magnetic resonance imaging (MRI), hyperthermia, photothermia, sample enrichment, bioassays, drug delivery, etc. With this review, the goal is to provide a comprehensive toolbox of insights into polymer or cell membrane-coated nanoparticles and their biomedical applications, while also addressing the challenges involved in translating such nanoparticles from laboratory benchtops to in vitro and in vivo applications. Furthermore, perspectives on future trends and developments in this rapidly evolving domain are provided.

Cell Membrane Camouflaged Biomimetic Nanoparticles as a Versatile Platform for Brain Diseases Treatment

Although there are various advancements in biomedical in the past few decades, there are still challenges in the treatment of brain diseases. The main difficulties are the inability to deliver a therapeutic dose of the drug to the brain through the blood-brain barrier (BBB) and the serious side effects of the drug. Thus, it is essential to select biocompatible drug carriers and novel therapeutic tools to better enhance the effect of brain disease treatment. In recent years, biomimetic nanoparticles (BNPs) based on natural cell membranes, which have excellent biocompatibility and low immunogenicity, are widely used in the treatment of brain diseases to enable the drug to successfully cross the BBB and target brain lesions. BNPs can prolong the circulation time in vivo, are more conducive to drug aggregation in brain lesions. Cell membranes (CMs) from cancer cells (CCs), red blood cells (RBCs), white blood cells (WBCs), and so on are used as biomimetic coatings for nanoparticles (NPs) to achieve the ability to target, evade clearance, or stimulate the immune system. This review summarizes the application of different cell sources as BNPs coatings in the treatment of brain diseases and discusses the possibilities and challenges of clinical translation.

Engineered Nanomaterials for Immunomodulation: A Review

The immune system usually provides a defense against invading pathogenic microorganisms and any other particulate contaminants. Nonetheless, it has been recently reported that nanomaterials can evade the immune system and modulate immunological responses due to their unique physicochemical characteristics. Consequently, nanomaterial-based activation of immune components, i.e., neutrophils, macrophages, and other effector cells, may induce inflammation and alter the immune response. Here, it is essential to distinguish the acute and chronic modulations triggered by nanomaterials to determine the possible risks to human health. Nanomaterials size, shape, composition, surface charge, and deformability are factors controlling their uptake by immune cells and the resulting immune responses. The exterior corona of molecules adsorbed over nanomaterials surfaces also influences their immunological effects. Here, we review current nanoengineering trends for targeted immunomodulation with an emphasis on the design, safety, and potential toxicity of nanomaterials. First, we describe the characteristics of engineered nanomaterials that trigger immune responses. Then, the biocompatibility and immunotoxicity of nanoengineered particles are debated, because these factors influence applications. Finally, future nanomaterial developments in terms of surface modifications, synergistic approaches, and biomimetics are discussed.

The Chimera of TPGS and Nanoscale Lipid Carriers as Lymphatic Drug Delivery Vehicles to Fight Metastatic Cancers

The lymphatic system (LS) plays a crucial role in fluid balance, transportation of macromolecules, and immune response. Moreover, LS is a channel for microbial invasion and cancer metastasis. Particularly, solid tumors, including lung, breast, melanoma, and prostate cancers, are metastasized across highways of LS. Subsequently, the fabrication of chimeric lymphatic drug delivery systems (LDDS) is a promising strategy to fight cancer metastasis and control microbial pandemics. In this regard, LDDS, in terms of PEG-nanoscaled lipid carriers, elicited a revolution during the COVID-19 pandemic as cargoes for mRNA vaccines. The drug delivered by the lymphatic pathway escapes first-pass metabolism and enhances the drug's bioavailability. Ample approaches, including synthesis of prodrugs, trigging of chylomicron biosynthesis, and fabrication of nanocarriers, facilitate lymphatic drug delivery. Specifically, nanoscales lipid cargoes have the propensity to lymphatic trafficking. Interestingly, TPGSengineered nanoscale lipid cargoes enhance lymphatic trafficking, increase tissue permeation, and, specifically, uptake. Moreover, they overcome biological barriers, control biodistribution, and enhance organelles localization. Most anticancer agents are non-specific, have low bioavailability, and induced drug resistance. Therefore, TPGS-engineered nanoscale lipid chimeras improve the therapeutic impact of anticancer agents. This review highlights lymphatic cancer metastasis, nanoscales lipid cargoes as LDDS, and their influence on lymphatic trafficking, besides the methods of LDD studies.

Exploring the Biomedical Applications of Biosynthesized Silver Nanoparticles Using Perilla frutescens Flavonoid Extract: Antibacterial, Antioxidant, and Cell Toxicity Properties against Colon Cancer Cells

The present study reports the biomimetic synthesis of silver nanoparticles (AgNPs) using a simple, cost effective and eco-friendly method. In this method, the flavonoid extract of Perilla frutescens (PFFE) was used as a bioreduction agent for the reduction of metallic silver into nanosilver, called P. frutescens flavonoid extract silver nanoparticles (PFFE-AgNPs). The Ultraviolet-Visible (UV-Vis) spectrum showed a characteristic absorption peak at 440 nm that confirmed the synthesis of PFFE-AgNPs. A Fourier transform infrared spectroscopic (FTIR) analysis of the PFFE-AgNPs revealed that flavonoids are involved in the bioreduction and capping processes. X-ray diffraction (XRD) and selected area electron diffraction (SAED) patterns confirmed the face-centered cubic (FCC) crystal structure of PFFE-AgNPs. A transmission electron microscopic (TEM) analysis indicated that the synthesized PFFE-AgNPs are 20 to 70 nm in size with spherical morphology and without any aggregation. Dynamic light scattering (DLS) studies showed that the average hydrodynamic size was 44 nm. A polydispersity index (PDI) of 0.321 denotes the monodispersed nature of PFFE-AgNPs. Further, a highly negative surface charge or zeta potential value (-30 mV) indicates the repulsion, non-aggregation, and stability of PFFE-AgNPs. PFFE-AgNPs showed cytotoxic effects against cancer cell lines, including human colon carcinoma (COLO205) and mouse melanoma (B16F10), with IC50 concentrations of 59.57 and 69.33 μg/mL, respectively. PFFE-AgNPs showed a significant inhibition of both Gram-positive (Listeria monocytogens and Enterococcus faecalis) and Gram-negative (Salmonella typhi and Acinetobacter baumannii) bacteria pathogens. PFFE-AgNPs exhibited in vitro antioxidant activity by quenching 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydrogen peroxide (H2O2) free radicals with IC50 values of 72.81 and 92.48 µg/mL, respectively. In this study, we also explained the plausible mechanisms of the biosynthesis, anticancer, and antibacterial effects of PFFE-AgNPs. Overall, these findings suggest that PFFE-AgNPs have potential as a multi-functional nanomaterial for biomedical applications, particularly in cancer therapy and infection control. However, it is important to note that further research is needed to determine the safety and efficacy of these nanoparticles in vivo, as well as to explore their potential in other areas of medicine.

Biomolecule-functionalized nanoformulations for prostate cancer theranostics

BACKGROUND

Even with the advancement in the areas of cancer nanotechnology, prostate cancer still poses a major threat to men's health. Nanomaterials and nanomaterial-derived theranostic systems have been explored for diagnosis, imaging, and therapy for different types of cancer still, for prostate cancer they have not delivered at full potential because of the limitations like in vivo biocompatibility, immune responses, precise targetability, and therapeutic outcome associated with the nanostructured system.

AIM OF REVIEW

Functionalizing nanomaterials with different biomolecules and bioactive agents provides advantages like specificity towards cancerous tumors, improved circulation time, and modulation of the immune response leading to early diagnosis and targeted delivery of cargo at the site of action.

KEY SCIENTIFIC CONCEPTS OF REVIEW

In this review, we have emphasized the classification and comparison of various nanomaterials based on biofunctionalization strategy and source of biomolecules such that it can be used for possible translation in clinical settings and future developments. This review highlighted the opportunities for embedding highly specific biological targeting moieties (antibody, aptamer, oligonucleotides, biopolymer, peptides, etc.) on nanoparticles which can improve the detection of prostate cancer-associated biomarkers at a very low limit of detection, direct visualization of prostate tumors and lastly for its therapy. Lastly, special emphasis was given to biomimetic nanomaterials which include functionalization with extracellular vesicles, exosomes and viral particles and their application for prostate cancer early detection and drug delivery. The present review paves a new pathway for next-generation biofunctionalized nanomaterials for prostate cancer theranostic application and their possibility in clinical translation.

A Review of Single-Cell Microrobots: Classification, Driving Methods and Applications

Single-cell microrobots are new microartificial devices that use a combination of single cells and artificial devices, with the advantages of small size, easy degradation and ease of manufacture. With externally driven strategies such as light fields, sound fields and magnetic fields, microrobots are able to carry out precise micromanipulations and movements in complex microenvironments. Therefore, single-cell microrobots have received more and more attention and have been greatly developed in recent years. In this paper, we review the main classifications, control methods and recent advances in the field of single-cell microrobot applications. First, different types of robots, such as cell-based microrobots, bacteria-based microrobots, algae-based microrobots, etc., and their design strategies and fabrication processes are discussed separately. Next, three types of external field-driven technologies, optical, acoustic and magnetic, are presented and operations realized in vivo and in vitro by applying these three technologies are described. Subsequently, the results achieved by these robots in the fields of precise delivery, minimally invasive therapy are analyzed. Finally, a short summary is given and current challenges and future work on microbial-based robotics are discussed.

Advances in treatment strategies based on scavenging reactive oxygen species of nanoparticles for atherosclerosis

The development of atherosclerosis (AS) is closely linked to changes in the plaque microenvironment, which consists primarily of the cells that form plaque and the associated factors they secrete. The onset of inflammation, lipid deposition, and various pathological changes in cellular metabolism that accompany the plaque microenvironment will promote the development of AS. Numerous studies have shown that oxidative stress is an important condition that promotes AS. The accumulation of reactive oxygen species (ROS) is oxidative stress's most important pathological change. In turn, the effects of ROS on the plaque microenvironment are complex and varied, and these effects are ultimately reflected in the promotion or inhibition of AS. This article reviews the effects of ROS on the microenvironment of atherosclerotic plaques and their impact on disease progression over the past five years and focuses on the progress of treatment strategies based on scavenging ROS of nanoparticles for AS. Finally, we also discuss the prospects and challenges of AS treatment.

Lipid-based nanoparticles for cancer immunotherapy

As the fourth most important cancer management strategy except surgery, chemotherapy and radiotherapy, cancer immunotherapy has been confirmed to elicit durable antitumor effects in the clinic by leveraging the patient's own immune system to eradicate the cancer cells. However, the limited population of patients who benefit from the current immunotherapies and the immune related adverse events hinder its development. The immunosuppressive microenvironment is the main cause of the failure, which leads to cancer immune evasion and immunity cycle blockade. Encouragingly, nanotechnology has been engineered to enhance the efficacy and reduce off-target toxicity of their therapeutic cargos by spatiotemporally controlling the biodistribution and release kinetics. Among them, lipid-based nanoparticles are the first nanomedicines to make clinical translation, which are now established platforms for diverse areas. In this perspective, we discuss the available lipid-based nanoparticles in research and market here, then describe their application in cancer immunotherapy, with special emphasis on the T cells-activated and macrophages-targeted delivery system. Through perpetuating each step of cancer immunity cycle, lipid-based nanoparticles can reduce immunosuppression and promote drug delivery to trigger robust antitumor response.

Genetically engineered cellular nanoparticles for biomedical applications

In recent years, nanoparticles derived from cellular membranes have been increasingly explored for the prevention and treatment of human disease. With their flexible design and ability to interface effectively with the surrounding environment, these biomimetic nanoparticles can outperform their traditional synthetic counterparts. As their popularity has increased, researchers have developed novel ways to modify the nanoparticle surface to introduce new or enhanced capabilities. Moving beyond naturally occurring materials derived from wild-type cells, genetic manipulation has proven to be a robust and flexible method by which nanoformulations with augmented functionalities can be generated. In this review, an overview of genetic engineering approaches to express novel surface proteins is provided, followed by a discussion on the various biomedical applications of genetically modified cellular nanoparticles.

Design Strategies for Cellular Nanosponges as Medical Countermeasures

The interest in using therapeutic nanoparticles to bind with harmful molecules or pathogens and subsequently neutralize their bioactivity has grown tremendously. Among various nanomedicine platforms, cell membrane-coated nanoparticles, namely, "cellular nanosponges," stand out for their broad-spectrum neutralization capability challenging to achieve in traditional countermeasure technologies. Such ability is attributable to their cellular function-based rather than target structure-based working principle. Integrating cellular nanosponges with various synthetic substrates further makes their applications exceptionally versatile and adaptive. This review discusses the latest cellular nanosponge technology focusing on how the structure-function relationship in different designs has led to versatile and potent medical countermeasures. Four design strategies are discussed, including harnessing native cell membrane functions for biological neutralization, functionalizing cell membrane coatings to enhance neutralization capabilities, combining cell membranes and functional cores for multimodal neutralization, and integrating cellular nanosponges with hydrogels for localized applications. Examples in each design strategy are selected, and the discussion is to highlight their structure-function relationships in complex disease settings. The review may inspire additional design strategies for cellular nanosponges and fulfill even broader medical applications.

Photothermal-accelerated urease-powered human serum albumin nanomotor for rapid and efficient photothermal and photodynamic cancer combination therapy

Nanomotors, as a new type of micro-device, show good performance in terms of rapid transportation and deep penetration through their autonomous motion. However, their ability to efficiently break physiological barriers still remains a great challenge. Herein, we first developed a thermal-accelerated urease driven human serum albumin (HSA) nanomotor based on photothermal intervention (PTI) to achieve chemotherapy drugfree-phototherapy. The HANM@FI (HSA-AuNR@FA@Ur@ICG) is composed of a main body of biocompatible HSA, modified by gold nanorods (AuNR) and loaded with functional molecules of folic acid (FA) and indocyanine green (ICG). It promotes its own motion by breaking down urea to produce carbon dioxide and ammonia. In particular, the nanomotor is conveniently operated via near-infrared combined photothermal therapy (PTT)/ photodynamic therapy (PDT) to achieve an accelerated De value from 0.73 μm²s^-1 to 1.01μm²s^-1, and ideal tumor ablation at the same time. In contrast to customary urease-driven nanodrug-stacked engine, this HANM@FI has both targeting and imaging-guided capabilities, and finally achieves superior anti-tumor effects without chemotherapy drugs, through a "two-in-one" (motor mobility plus unique phototherapy in chemotherapy-drugfree phototherapy) strategy. This PTI effect with urease-driven nanomotors may offer further possibilities for future clinical applications of nanomedicines by enabling deep penetration and a subsequent chemotherapy-drugfree combination therapy strategy.

Versatile biomimetic nanomedicine for treating cancer and inflammation disease

Nanosized drug delivery systems (NDDSs) have emerged as a powerful tool to optimize drug delivery in complex diseases, including cancer and inflammation. However, the therapeutic effect of NDDSs is still far from satisfactory due to their poor circulation time, low delivery efficiency, and innate toxicity. Fortunately, biomimetic approaches offer new opportunities to develop nanomedicine, which is derived from a variety of native biomolecules including cells, exosomes, bacteria, and so on. Since inheriting the superior biocompatibility and versatile functions of natural materials, biomimetic nanomedicine can mimic biological processes, prolong blood circulation, and lower immunogenicity, serving as a desired platform for precise drug delivery for treating cancer and inflammatory disease. In this review, we outline recent advances in biomimetic NDDSs, which consist of two concepts: biomimetic exterior camouflage and bioidentical molecule construction. We summarize engineering strategies that further functionalized current biomimetic NDDSs. A series of functional biomimetic NDDSs created by our group are introduced. We conclude with an outlook on remaining challenges and possible directions for biomimetic NDDSs. We hope that better technologies can be inspired and invented to advance drug delivery systems for cancer and inflammation therapy.

Polylactic-co-glycolic acid-based nanoparticles modified with peptides and other linkers cross the blood-brain barrier for targeted drug delivery

Because of the blood-brain barrier, only a limited fraction of drugs can penetrate the brain. As a result, there is a need to take larger doses of the drug, which may result in numerous undesirable side effects. Over the past few decades, a plethora of research has been conducted to address this issue. In recent years, the field of nanomedicine research has reported promising findings. Currently, numerous types of polylactic-co-glycolic acid-based drug-delivery systems are being studied, and great progress has been made in the modification of their surfaces with a variety of ligands. In this review, the authors highlight the preparation of polylactic-co-glycolic acid-based nanoparticles and single- and dual-targeted peptide modifications for site-specific drug delivery into the brain.

Cyclodextrin-Based Arsenal for Anti-Cancer Treatments

Anti-cancer drugs are mostly limited in their use due to poor physicochemical and biopharmaceutical properties. Their lower solubility is the most common hurdle limiting their use upto their potential. In the recent years, the cyclodextrin (CD) complexation have emerged as existing approach to overcome the problem of poor solubility. CD-based nano-technological approaches are safe, stable and showed well in vivo tolerance and greater payload for encapsulation of hydrophobic drugs for the targeted delivery. They are generally chosen due to their ability to get self-assembled to form liposomes, nanoparticles, micelles and nano-sponges etc. This review paper describes a birds-eye view of the various CD-based nano-technological approaches applied for the delivery of anti-cancer moieties to the desired target such as CD based liposomes, niosomes, niosoponges, micelles, nanoparticles, monoclonal antibody, magnetic nanoparticles, small interfering RNA, nanorods, miscellaneous formulation of anti-cancer drugs containing CD. Moreover, the author also summarizes the various shortcomings of such a system and their way ahead.

The role of cell membrane-coated nanoparticles as a novel treatment approach in glioblastoma

Glioblastoma multiform (GBM) is the most prevalent and deadliest primary brain malignancy in adults, whose median survival rate does not exceed 15 months after diagnosis. The conventional treatment of GBM, including maximal safe surgery followed by chemotherapy and radiotherapy, usually cannot lead to notable improvements in the disease prognosis and the tumor always recurs. Many GBM characteristics make its treatment challenging. The most important ones are the impermeability of the blood-brain barrier (BBB), preventing chemotherapeutic drugs from reaching in adequate amounts to the tumor site, intratumoral heterogeneity, and roles of glioblastoma stem cells (GSCs). To overcome these barriers, the recently-developed drug-carrying approach using nanoparticles (NPs) may play a significant role. NPs are tiny particles, usually less than 100 nm showing various diagnostic and therapeutic medical applications. In this regard, cell membrane (CM)-coated NPs demonstrated several promising effects in GBM in pre-clinical studies. They benefit from fewer adverse effects due to their specific targeting of tumor cells, biocompatibility because of their CM surfaces, prolonged half-life, easy penetrating of the BBB, and escaping from the immune reaction, making them an attractive option for GBM treatment. To date, CM-coated NPs have been applied to enhance the effectiveness of major therapeutic approaches in GBM treatment, including chemotherapy, immunotherapy, gene therapy, and photo-based therapies. Despite the promising results in pre-clinical studies regarding the effectiveness of CM-coated NPs in GBM, significant barriers like high expenses, complex preparation processes, and unknown long-term effects still hinder its mass production for the clinic. In this regard, the current study aims to provide an overview of different characteristics of CM-coated NPs and comprehensively investigate their application as a novel treatment approach in GBM.

Advancement and Applications of Platelet-inspired Nanoparticles: A Paradigm for Cancer Targeting

Platelet-inspired nanoparticles have ignited the possibility of new opportunities for producing similar biological particulates, such as structural cellular and vesicular components, as well as various viral forms, to improve biocompatible features that could improve the nature of biocompatible elements and enhance therapeutic efficacy. The simplicity and more effortless adaptability of such biomimetic techniques uplift the delivery of the carriers laden with cellular structures, which has created varied opportunities and scope of merits like; prolongation in circulation and alleviating immunogenicity improvement of the site-specific active targeting. Platelet-inspired nanoparticles or medicines are the most recent nanotechnology-based drug targeting systems used mainly to treat blood-related disorders, tumors, and cancer. The present review encompasses the current approach of platelet-inspired nanoparticles or medicines that have boosted the scientific community from versatile fields to advance biomedical sciences. Surprisingly, this knowledge has streamlined to development of newer diagnostic methods, imaging techniques, and novel nanocarriers, which might further help in the treatment protocol of the various diseased conditions. The review primarily focuses on the novel advancements and recent patents in nanoscience and nanomedicine that could be streamlined in the future for the management of progressive cancers and tumor targeting. Rigorous technological advancements like biomimetic stem cells, pH-sensitive drug delivery of nanoparticles, DNA origami devices, virosomes, nano cells like exosomes mimicking nanovesicles, DNA nanorobots, microbots, etc., can be implemented effectively for target-specific drug delivery.

“Motile-targeting” drug delivery platforms based on micro/nanorobots for tumor therapy

Traditional drug delivery systems opened the gate for tumor-targeted therapy, but they generally took advantage of enhanced permeability and retention or ligand-receptor mediated interaction, and thus suffered from limited recognition range (<0.5 nm) and low targeting efficiency (0.7%, median). Alternatively, micro/nanorobots (MNRs) may act as emerging “motile-targeting” drug delivery platforms to deliver therapeutic payloads, thereby making a giant step toward effective and safe cancer treatment due to their autonomous movement and navigation in biological media. This review focuses on the most recent developments of MNRs in “motile-targeting” drug delivery. After a brief introduction to traditional tumor-targeted drug delivery strategies and various MNRs, the representative applications of MNRs in “motile-targeting” drug delivery are systematically streamlined in terms of the propelling mechanisms. Following a discussion of the current challenges of each type of MNR in biomedical applications, as well as future prospects, several promising designs for MNRs that could benefit in “motile-targeting” drug delivery are proposed. This work is expected to attract and motivate researchers from different communities to advance the creation and practical application of the “motile-targeting” drug delivery platforms.

Exploring the role of nanomedicines for the therapeutic approach of central nervous system dysfunction: At a glance

In recent decades, research scientists, molecular biologists, and pharmacologists have placed a strong emphasis on cutting-edge nanostructured materials technologies to increase medicine delivery to the central nervous system (CNS). The application of nanoscience for the treatment of neurodegenerative diseases (NDs) such as Alzheimer’s disease (AD), Parkinson’s disease (PD), multiple sclerosis (MS), Huntington’s disease (HD), brain cancer, and hemorrhage has the potential to transform care. Multiple studies have indicated that nanomaterials can be used to successfully treat CNS disorders in the case of neurodegeneration. Nanomedicine development for the cure of degenerative and inflammatory diseases of the nervous system is critical. Nanoparticles may act as a drug transporter that can precisely target sick brain sub-regions, boosting therapy success. It is important to develop strategies that can penetrate the blood–brain barrier (BBB) and improve the effectiveness of medications. One of the probable tactics is the use of different nanoscale materials. These nano-based pharmaceuticals offer low toxicity, tailored delivery, high stability, and drug loading capacity. They may also increase therapeutic effectiveness. A few examples of the many different kinds and forms of nanomaterials that have been widely employed to treat neurological diseases include quantum dots, dendrimers, metallic nanoparticles, polymeric nanoparticles, carbon nanotubes, liposomes, and micelles. These unique qualities, including sensitivity, selectivity, and ability to traverse the BBB when employed in nano-sized particles, make these nanoparticles useful for imaging studies and treatment of NDs. Multifunctional nanoparticles carrying pharmacological medications serve two purposes: they improve medication distribution while also enabling cell dynamics imaging and pharmacokinetic study. However, because of the potential for wide-ranging clinical implications, safety concerns persist, limiting any potential for translation. The evidence for using nanotechnology to create drug delivery systems that could pass across the BBB and deliver therapeutic chemicals to CNS was examined in this study.

Developing FRET Networks for Sensing

Förster resonance energy transfer (FRET) is a widely used fluorescence-based sensing mechanism. To date, most implementations of FRET sensors have relied on a discrete donor-acceptor pair for detection of each analytical target. FRET networks are an emerging concept in which target recognition perturbs a set of interconnected FRET pathways between multiple emitters. Here, we review the energy transfer topologies and scaffold materials for FRET networks, propose a general nomenclature, and qualitatively summarize the dynamics of the competitive, sequential, homoFRET, and heteroFRET pathways that constitute FRET networks. Implementations of FRET networks for sensing are also described, including concentric FRET probes, other single-vector multiplexing, and logic gates and switches. Unresolved questions and future research directions for current systems are discussed, as are potential but currently unexplored applications of FRET networks in sensing.

Emerging vaccine nanotechnology: From defense against infection to sniping cancer

Looking retrospectively at the development of humanity, vaccination is an unprecedented medical landmark that saves lives by harnessing the human immune system. During the ongoing coronavirus disease 2019 (COVID-19) pandemic, vaccination is still the most effective defense modality. The successful clinical application of the lipid nanoparticle-based Pfizer/BioNTech and Moderna mRNA COVID-19 vaccines highlights promising future of nanotechnology in vaccine development. Compared with conventional vaccines, nanovaccines are supposed to have advantages in lymph node accumulation, antigen assembly, and antigen presentation; they also have, unique pathogen biomimicry properties because of well-organized combination of multiple immune factors. Beyond infectious diseases, vaccine nanotechnology also exhibits considerable potential for cancer treatment. The ultimate goal of cancer vaccines is to fully mobilize the potency of the immune system as a living therapeutic to recognize tumor antigens and eliminate tumor cells, and nanotechnologies have the requisite properties to realize this goal. In this review, we summarize the recent advances in vaccine nanotechnology from infectious disease prevention to cancer immunotherapy and highlight the different types of materials, mechanisms, administration methods, as well as future perspectives.

Manipulation of the tumor immuno-microenvironment via TAM-targeted expression of transcription factors

An immunosuppressive tumor microenvironment (TME) leads to cancer growth, metastasis, and therapeutic resistance. Immunomodulatory immunotherapy aims to skew the immunosuppressive TME back to an immune active state. Tumor-associated macrophages (TAMs) are a critical component of the TME that are actively involved in tumor-specific inflammation and immunosuppression. TAMs exhibit a diverse range of phenotypes and functions, from pro-tumor to anti-tumor. The plasticity of TAMs makes them a promising target for immunotherapy, and TAM-targeted therapies via different strategies have shown great potential. This review discusses current TAM-specific delivery targets and genes of interest for TAM-reprogramming. As phagocytic cells, TAMs have several receptors that have been used to increase TAM-targeted in vivo delivery. Furthermore, a promising approach for reprogramming TAMs is to activate or suppress specific transcription factors in the signal transducers and activators of transcription (STAT) and interferon regulatory factor (IRF) families. Altering TAM transcription factor expression results in a potent shift in cytokine expression and overall TAM function potentially tipping the balance from an immunosuppressive to an immune active TME.

Organotropic Targeting of Biomimetic Nanoparticles to Treat Lung Disease

Active targeting strategies aimed at improving drug homing while reducing systemic toxicity are widely being pursued in the growing field of nanomedicine. While they can be effective, these approaches often require the identification of cell-specific targets and in-depth knowledge of receptor binding interactions. More recently, there has been significant interest in biomimetic nanoformulations capable of replicating the properties of naturally occurring systems. In particular, the advent of cell membrane coating nanotechnology has enabled researchers to leverage the inherent tropisms displayed by living cells, bypassing many of the challenges associated with traditional bottom-up nanoengineering. In this work, we report on a biomimetic organotropic nanodelivery system for localizing therapeutic payloads to the lungs. Metastatic breast cancer exosomes, which are lung tropic due to their unique surface marker expression profile, are used to coat nanoparticle cores loaded with the anti-inflammatory drug dexamethasone. In vivo, these nanoparticles demonstrate enhanced accumulation in lung tissue and significantly reduce proinflammatory cytokine burden in a lung inflammation model. Overall, this work highlights the potential of using biomimetic organ-level delivery strategies for the management of certain disease conditions.

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.

Re-engineered imaging agent using biomimetic approaches

Recent progress in biomedical technology, the clinical bioimaging, has a greater impact on the diagnosis, treatment, and prevention of disease, especially by early intervention and precise therapy. Varieties of organic and inorganic materials either in the form of small molecules or nano-sized materials have been engineered as a contrast agent (CA) to enhance image resolution among different tissues for the detection of abnormalities such as cancer and vascular occlusion. Among different innovative imaging agents, contrast agents coupled with biologically derived endogenous platform shows the promising application in the biomedical field, including drug delivery and bioimaging. Strategy using biocomponents such as cells or products of cells as a delivery system predominantly reduces the toxic behavior of its cargo, as these systems reduce non-specific distribution by navigating its cargo toward the targeted location. The hypothesis is that depending on the original biological role of the naïve cell, the contrast agents carried by such a system can provide corresponding natural designated behavior. Therefore, by combining properties of conventional synthetic molecules and nanomaterials with endogenous cell body, new solutions in the field of bioimaging to overcome biological barriers have been offered as innovative bioengineering. In this review, we will discuss the engineering of cell and cell-derived components as a delivery system for various contrast agents to achieve clinically relevant contrast for diagnosis and study underlining mechanism of disease progression. This article is categorized under: Nanotechnology Approaches to Biology > Cells at the Nanoscale Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Nanoparticles for vaccine and gene therapy: Overcoming the barriers to nucleic acid delivery

Nucleic acid therapeutics can be used to control virtually every aspect of cell behavior and therefore have significant potential to treat genetic disorders, infectious diseases, and cancer. However, while clinically approved to treat a small number of diseases, the full potential of nucleic acid therapeutics is hampered by inefficient delivery. Nucleic acids are large, highly charged biomolecules that are sensitive to degradation and so the approaches to deliver these molecules differ significantly from traditional small molecule drugs. Current studies suggest less than 1% of the injected nucleic acid dose is delivered to the target cell in an active form. This inefficient delivery increases costs and limits their use to applications where a small amount of nucleic acid is sufficient. In this review, we focus on two of the major barriers to efficient nucleic acid delivery: (1) delivery to the target cell and (2) transport to the subcellular compartment where the nucleic acids are therapeutically active. We explore how nanoparticles can be modified with targeting ligands to increase accumulation in specific cells, and how the composition of the nanoparticle can be engineered to manipulate or disrupt cellular membranes and facilitate delivery to the optimal subcellular compartments. Finally, we highlight how with intelligent material design, nanoparticle delivery systems have been developed to deliver nucleic acids that silence aberrant genes, correct genetic mutations, and act as both therapeutic and prophylactic vaccines. This article is categorized under: Nanotechnology Approaches to Biology > Cells at the Nanoscale Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Biology-Inspired Nanomaterials > Lipid-Based Structures.

Cell/Bacteria-Based Bioactive Materials for Cancer Immune Modulation and Precision Therapy

Numerous clinical trials for cancer precision medicine research are limited due to the drug resistance, side effects, and low efficacy. Unsatisfactory outcomes are often caused by complex physiologic barriers and abnormal immune events in tumors, such as tumor target alterations and immunosuppression. Cell/bacteria-derived materials with unique bioactive properties have emerged as attractive tools for personalized therapy in cancer. Naturally derived bioactive materials, such as cell and bacterial therapeutic agents with native tropism or good biocompatibility, can precisely target tumors and effectively modulate immune microenvironments to inhibit tumors. Here, the recent advances in the development of cell/bacteria-based bioactive materials for immune modulation and precision therapy in cancer are summarized. Cell/bacterial constituents, including cell membranes, bacterial vesicles, and other active substances have inherited their unique targeting properties and antitumor capabilities. Strategies for engineering living cell/bacteria to overcome complex biological barriers and immunosuppression to promote antitumor efficacy are also summarized. Moreover, past and ongoing trials involving personalized bioactive materials and promising agents such as cell/bacteria-based micro/nano-biorobotics are further discussed, which may become another powerful tool for treatment in the near future.

Role of proteins in the biosynthesis and functioning of metallic nanoparticles

Proteins are known to play important roles in the biosynthesis of metallic nanoparticles (NPs), which are biological substitutes for conventionally used chemical capping and stabilizing agents. When a pristine nanoparticle comes in contact with a biological media or system, a bimolecular layer is formed on the surface of the nanoparticle and is primarily composed of proteins. The role of proteins in the biosynthesis and further uptake, translocation, and bio-recognition of nanoparticles is documented in the literature. But, a complete understanding has not been achieved concerning the mechanism for protein-mediated nanoparticle biosynthesis and the role proteins play in the interaction and recognition of nanoparticles, aiding its uptake and assimilation into the biological system. This review critically evaluates the knowledge and gaps in the protein-mediated biosynthesis of nanoparticles. In particular, we review the role of proteins in multiple facets of metallic nanoparticle biosynthesis, the interaction of proteins with metallic nanoparticles for recognition and interaction with cells, and the toxic potential of protein-nanoparticle complexes when presented to the cell.

Human Cancer Cell Membrane-Cloaked Fe3O4 Nanocubes for Homologous Targeting Improvement

Surface modification of nanoparticles with cellular protein components is a new biomimetic modification strategy, which utilizes the inherent affinity between homologous cells to introduce the same surface molecules into nanoparticles to improve the targeting performance. In this study, oleic acid (OA)-coated Fe₃O₄ nanocubes were prepared by a high-temperature thermal decomposition method and modified by 3, 4-dihydroxyphenylpropionic acid (DHCA); then, HeLa cell membranes were introduced onto the surface of the nanocubes through mixed coextrusion to try to endow them with the targeting function of natural cells. The results show that the prepared Fe₃O₄ nanocubes have high monodispersity, excellent water solubility, and biocompatibility. Moreover, the Fe₃O₄ nanocubes encapsulated by cellular protein show an obvious core-shell structure and the specific targeting property to HeLa cells is improved significantly, which is expected to be used in clinical targeted diagnosis and treatment of cancer.

Genetically engineered cell membrane-coated nanoparticles for targeted delivery of dexamethasone to inflamed lungs

As numerous diseases are associated with increased local inflammation, directing drugs to the inflamed sites can be a powerful therapeutic strategy. One of the common characteristics of inflamed endothelial cells is the up-regulation of vascular cell adhesion molecule-1 (VCAM-1). Here, the specific affinity between very late antigen-4 (VLA-4) and VCAM-1 is exploited to produce a biomimetic nanoparticle formulation capable of targeting inflammation. The plasma membrane from cells genetically modified to constitutively express VLA-4 is coated onto polymeric nanoparticle cores, and the resulting cell membrane-coated nanoparticles exhibit enhanced affinity to target cells that overexpress VCAM-1 in vitro. A model anti-inflammatory drug, dexamethasone, is encapsulated into the nanoformulation, enabling improved delivery of the payload to inflamed lungs and significant therapeutic efficacy in vivo. Overall, this work leverages the unique advantages of biological membrane coatings to engineer additional targeting specificities using naturally occurring target-ligand interactions.

Bacteria-Inspired Nanomedicine

The natural world has provided a host of materials and inspiration for the field of nanomedicine. By taking design cues from naturally occurring systems, the nanoengineering of advanced biomimetic platforms has significantly accelerated over the past decade. In particular, the biomimicry of bacteria, with their motility, taxis, immunomodulation, and overall dynamic host interactions, has elicited substantial interest and opened up exciting avenues of research. More recently, advancements in genetic engineering have given way to more complex and elegant systems with tunable control characteristics. Furthermore, bacterial derivatives such as membrane ghosts, extracellular vesicles, spores, and toxins have proven advantageous for use in nanotherapeutic applications, as they preserve many of the features from the original bacteria while also offering distinct advantages. Overall, bacteria-inspired nanomedicines can be employed in a range of therapeutic settings, from payload delivery to immunotherapy, and have proven successful in combatting both cancer and infectious disease.

Orchestration of biomimetic membrane coating and nanotherapeutics in personalized anticancer therapy

Nanoparticle-based therapeutic and detectable modalities can augment anticancer efficiency, holding potential in capable target and suppressive metastases post administration. However, the individual discrepancies of the current "one-size-fits-all" strategies for anticancer nanotherapeutics have heralded the need for "personalized therapy". Benefiting from the special inherency of various cells, diverse cell membrane-coated nanoparticles (CMCNs) were established on a patient-by-patient basis, which would facilitate the personalized treatment of individual cancer patients. CMCNs in a complex microenvironment can evade the immune system and target homologous tumors with a suppressed immune response, as well as a prolonged circulation time, consequently increasing the drug accumulation at the tumor site and anticancer therapeutic efficacy. This review focuses on the emerging strategies and advances of CMCNs to synergistically integrate the merit of source cells with nanoparticulate delivery systems for the orchestration of personalized anticancer nanotherapeutics, thus discussing their rationalities in facilitating chemotherapy, imaging, immunotherapy, phototherapy, radiotherapy, sonodynamic, magnetocaloric, chemodynamic and gene therapy. Furthermore, the mechanism, challenges and opportunities of CMCNs in personalized anticancer therapy were highlighted to further boost cooperation from different fields, including materials science, chemistry, medicine, pharmacy and biology for the lab-to-clinic translation of CMCNs combined with the individual advantages of source cells and nanotherapeutics.

Emerging Approaches to Functionalizing Cell Membrane-Coated Nanoparticles

There has been significant interest in developing cell membrane-coated nanoparticles due to their unique abilities of biomimicry and biointerfacing. As the technology progresses, it becomes clear that the application of these nanoparticles can be drastically broadened if additional functions beyond those derived from the natural cell membranes can be integrated. Herein, we summarize the most recent advances in the functionalization of cell membrane-coated nanoparticles. In particular, we focus on emerging methods, including (1) lipid insertion, (2) membrane hybridization, (3) metabolic engineering, and (4) genetic modification. These approaches contribute diverse functions in a nondisruptive fashion while preserving the natural function of the cell membranes. They also improve on the multifunctional and multitasking ability of cell membrane-coated nanoparticles, making them more adaptive to the complexity of biological systems. We hope that these approaches will serve as inspiration for more strategies and innovations to advance cell membrane coating technology.

Intratumoral immunotherapy using platelet-cloaked nanoparticles enhances antitumor immunity in solid tumors

Intratumoral immunotherapy is an emerging modality for the treatment of solid tumors. Toll-like receptor (TLR) agonists have shown promise for eliciting immune responses, but systemic administration often results in the development of adverse side effects. Herein, we investigate whether localized delivery of the TLR agonist, resiquimod (R848), via platelet membrane-coated nanoparticles (PNP-R848) elicits antitumor responses. The membrane coating provides a means of enhancing interactions with the tumor microenvironment, thereby maximizing the activity of R848. Intratumoral administration of PNP-R848 strongly enhances local immune activation and leads to complete tumor regression in a colorectal tumor model, while providing protection against repeated tumor re-challenges. Moreover, treatment of an aggressive breast cancer model with intratumoral PNP-R848 delays tumor growth and inhibits lung metastasis. Our findings highlight the promise of locally delivering immunostimulatory payloads using biomimetic nanocarriers, which possess advantages such as enhanced biocompatibility and natural targeting affinities.

Recent Advances in Cell Membrane-Derived Biomimetic Nanotechnology for Cancer Immunotherapy

Immunotherapy will significantly impact the standard of care in cancer treatment. Recent advances in nanotechnology can improve the efficacy of cancer immunotherapy. However, concerns regarding efficiency of cancer nanomedicine, complex tumor microenvironment, patient heterogeneity, and systemic immunotoxicity drive interest in more novel approaches to be developed. For this purpose, biomimetic nanoparticles are developed to make innovative changes in the delivery and biodistribution of immunotherapeutics. Biomimetic nanoparticles have several advantages that can advance the clinical efficacy of cancer immunotherapy. Thus there is a greater push toward the utilization of biomimetic nanotechnology for developing effective cancer immunotherapeutics that demonstrate increased specificity and potency. The recent works and state-of-the-art strategies for anti-tumor immunotherapeutics are highlighted here, and particular emphasis has been given to the applications of cell-derived biomimetic nanotechnology for cancer immunotherapy.

Platelet membrane camouflaged nanoparticles: Biomimetic architecture for targeted therapy

Cell membrane coating strategy is one of the promising techniques for biomimetic functionalization of nanoparticle. The biomimetic nanoparticles camouflage themselves utilizing the fundamental properties of native cells. Cell membranes are extracted from various cells to cloak the nanoparticles for targeted drug delivery. Platelet membrane is one such cell membrane proposing itself as a potential camouflager to escape the immune surveillance and aid prolonged blood circulation with minimum systemic cytotoxicity. Platelets play a very important role in the physiological functions of the body and also feature in few pathological disorders like cancer, atherosclerosis and rheumatoid arthritis. This review comprises of preparation and characterization of platelet membrane camouflaged nanoparticles and also focuses on their recent developments towards targeted therapy in cancer, immune diseases, atherosclerosis and phototherapy. Although platelet membrane camouflaged nanoparticles are currently in the preliminary stage of development, there is huge potential to explore this biodegradable and biocompatible delivery system.

Nanobiotechnology for Agriculture: Smart Technology for Combating Nutrient Deficiencies with Nanotoxicity Challenges

Nanobiotechnology in agriculture is a driver for modern-day smart, efficient agricultural practices. Nanoparticles have been shown to stimulate plant growth and disease resistance. The goal of sustainable farming can be accomplished by developing and sustainably exploiting the fruits of nanobiotechnology to balance the advantages nanotechnology provides in tackling environmental challenges. This review aims to advance our understanding of nanobiotechnology in relevant areas, encourage interactions within the research community for broader application, and benefit society through innovation to realize sustainable agricultural practices. This review critically evaluates what is and is not known in the domain of nano-enabled agriculture. It provides a holistic view of the role of nanobiotechnology in multiple facets of agriculture, from the synthesis of nanoparticles to controlled and targeted delivery, uptake, translocation, recognition, interaction with plant cells, and the toxicity potential of nanoparticle complexes when presented to plant cells.

Targeted nano-delivery strategies for facilitating thrombolysis treatment in ischemic stroke

Ischemic stroke is one of the major causes of severe disability and death worldwide. It is mainly caused by a sudden reduction in cerebral blood flow due to obstruction of the supplying vessel by thrombi and subsequent initiation of a complex cascade of pathophysiological changes, which ultimately lead to brain ischemia and even irreversible infarction. Thus, timely and effective thrombolysis therapy remains a mainstay for acute ischemic stroke treatment. Tissue plasminogen activator (tPA), the only thrombolytic agent approved globally, provides substantial benefits by exerting a fibrinolysis effect, recovering the blood supply in occluded vessels and, thereby, salvaging the ischemic tissue. However, the clinical application of tPA was limited because of a few unsolved issues, such as a narrow therapeutic window, hemorrhagic complications, and limited thrombolytic efficacy, especially, for large thrombi. With the prosperous development of nanotechnology, a series of targeted delivery strategies and nanocomposites have been extensively investigated for delivering thrombolytic agents to facilitate thrombolysis treatment. Excitingly, numerous novel attempts have been reported to be effective in extending the half-life, targeting the thrombus site, and improving the thrombolytic efficacy in preclinical models. This article begins with a brief introduction to ischemic stroke, then describes the current state of thrombolysis treatment and, finally, introduces the application of various nanotechnology-based strategies for targeted delivery of thrombolytic agents. Representative studies are reviewed according to diverse strategies and nano-formulations, with the aim of providing integrated and up-to-date information and to improve the development of thrombolysis treatment for stroke patients.

Recent Advances and Implication of Bioengineered Nanomaterials in Cancer Theranostics

Cancer is one of the most common causes of death and affects millions of lives every year. In addition to non-infectious carcinogens, infectious agents contribute significantly to increased incidence of several cancers. Several therapeutic techniques have been used for the treatment of such cancers. Recently, nanotechnology has emerged to advance the diagnosis, imaging, and therapeutics of various cancer types. Nanomaterials have multiple advantages over other materials due to their small size and high surface area, which allow retention and controlled drug release to improve the anti-cancer property. Most cancer therapies have been known to damage healthy cells due to poor specificity, which can be avoided by using nanosized particles. Nanomaterials can be combined with various types of biomaterials to make it less toxic and improve its biocompatibility. Based on these properties, several nanomaterials have been developed which possess excellent anti-cancer efficacy potential and improved diagnosis. This review presents the latest update on novel nanomaterials used to improve the diagnostic and therapeutic of pathogen-associated and non-pathogenic cancers. We further highlighted mechanistic insights into their mode of action, improved features, and limitations.

Nano-Biomimetic Drug Delivery Vehicles: Potential Approaches for COVID-19 Treatment

The current COVID-19 pandemic has tested the resolve of the global community with more than 35 million infections worldwide and numbers increasing with no cure or vaccine available to date. Nanomedicines have an advantage of providing enhanced permeability and retention and have been extensively studied as targeted drug delivery strategies for the treatment of different disease. The role of monocytes, erythrocytes, thrombocytes, and macrophages in diseases, including infectious and inflammatory diseases, cancer, and atherosclerosis, are better understood and have resulted in improved strategies for targeting and in some instances mimicking these cell types to improve therapeutic outcomes. Consequently, these primary cell types can be exploited for the purposes of serving as a "Trojan horse" for targeted delivery to identified organs and sites of inflammation. State of the art and potential utilization of nanocarriers such as nanospheres/nanocapsules, nanocrystals, liposomes, solid lipid nanoparticles/nano-structured lipid carriers, dendrimers, and nanosponges for biomimicry and/or targeted delivery of bioactives to cells are reported herein and their potential use in the treatment of COVID-19 infections discussed. Physicochemical properties, viz., hydrophilicity, particle shape, surface charge, composition, concentration, the use of different target-specific ligands on the surface of carriers, and the impact on carrier efficacy and specificity are also discussed.

The Role of Natural Compounds and their Nanocarriers in the Treatment of CNS Inflammation

Neuroinflammation, which is involved in various inflammatory cascades in nervous tissues, can result in persistent and chronic apoptotic neuronal cell death and programmed cell death, triggering various degenerative disorders of the central nervous system (CNS). The neuroprotective effects of natural compounds against neuroinflammation are mainly mediated by their antioxidant, anti-inflammatory, and antiapoptotic properties that specifically promote or inhibit various molecular signal transduction pathways. However, natural compounds have several limitations, such as their pharmacokinetic properties and stability, which hinder their clinical development and use as medicines. This review discusses the molecular mechanisms of neuroinflammation and degenerative diseases of CNS. In addition, it emphasizes potential natural compounds and their promising nanocarriers for overcoming their limitations in the treatment of neuroinflammation. Moreover, recent promising CNS inflammation-targeted nanocarrier systems implementing lesion site-specific active targeting strategies for CNS inflammation are also discussed.

Clinical failure of nanoparticles in cancer: mimicking nature's solutions

The use of nanotechnology has become a promising approach in the treatment of cancer. However, most intravenously injected nanoparticles (NPs) do not effectively reach the tumor mass due to the biological barriers in the body. In an attempt to unify clinical criteria and basic research, we have collected the latest studies and described novel alternatives such as the use of NPs covered with cell membranes to increase NP delivery efficiency. Furthermore, we focus on the prospect of using the cell's natural messengers, exosomes, as vehicles to transport anti-cancer agents and we discuss the technical complications involved. Finally, we propose novel approaches to produce engineered exosomes which may overcome such technical limitations in order to achieve a proper anti-cancer nanotherapy.