Current targeting strategies and advanced nanoplatforms for atherosclerosis therapy

Atherosclerosis is one of the major causes of death worldwide, and it is closely related to many cardiovascular diseases, such as stroke, myocardial infraction and angina. Although traditional surgical and pharmacological interventions can effectively retard or slow down the progression of atherosclerosis, it is very difficult to prevent or even reverse this disease. In recent years, with the rapid development of nanotechnology, various nanoagents have been designed and applied to different diseases including atherosclerosis. The unique atherosclerotic microenvironment with signature biological components allows nanoplatforms to distinguish atherosclerotic lesions from normal tissue and to approach plaques specifically. Based on the process of atherosclerotic plaque formation, this review summarises the nanodrug delivery strategies for atherosclerotic therapy, trying to provide help for researchers to understand the existing atherosclerosis management approaches as well as challenges and to reasonably design anti-atherosclerotic nanoplatforms.

Combination Nano-Delivery Systems Remodel the Immunosuppressive Tumor Microenvironment for Metastatic Triple-Negative Breast Cancer Therapy

Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer for which effective therapies are lacking. Targeted remodeling of the immunosuppressive tumor microenvironment (TME) and activation of the body's immune system to fight tumors with well-designed nanoparticles have emerged as pivotal breakthroughs in tumor treatment. To simultaneously remodel the immunosuppressive TME and trigger immune responses, we designed two potential therapeutic nanodelivery systems to inhibit TNBC. First, the bromodomain-containing protein 4 (BRD4) inhibitor JQ1 and the cyclooxygenase-2 (COX-2) inhibitor celecoxib (CXB) were coloaded into chondroitin sulfate (CS) to obtain CS@JQ1/CXB nanoparticles (NPs). Then, the biomimetic nanosystem MM@P3 was prepared by coating branched polymer poly(β-amino ester) self-assembled NPs with melittin embedded macrophage membranes (MM). Both in vitro and in vivo, the CS@JQ1/CXB and MM@P3 NPs showed excellent immune activation efficiencies. Combination treatment exhibited synergistic cytotoxicity, antimigration ability, and apoptosis-inducing and immune activation effects on TNBC cells and effectively suppressed tumor growth and metastasis in TNBC tumor-bearing mice by activating the tumor immune response and inhibiting angiogenesis. In summary, this study offers a novel combinatorial immunotherapeutic strategy for the clinical TNBC treatment.

Efficient Delivery of Lomitapide using Hybrid Membrane-Coated Tetrahedral DNA Nanostructures for Glioblastoma Therapy

Glioblastoma (GBM) is the most aggressive and prevalent primary malignant tumor of the central nervous system. Traditional chemotherapy has poor therapeutic effects and significant side effects due to drug resistance, the natural blood-brain barrier (BBB), and nonspecific distribution, leading to a lack of clinically effective therapeutic drugs. Here, 1430 small molecule compounds are screened based on a high-throughput drug screening platform and a novel anti-GBM drug, lomitapide (LMP) is obtained. Furthermore, a bionic nanodrug delivery system (RFA NPs) actively targeting GBM is constructed, which mainly consists of tetrahedral DNA nanocages (tFNA NPs) loaded with LMP as the core and a folate-modified erythrocyte-cancer cell-macrophage hybrid membrane (FRUR) as the shell. FRUR camouflage conferred unique features on tFNA NPs, including excellent biocompatibility, improved pharmacokinetic profile, efficient BBB permeability, and tumor targeting ability. The results show that the LMP RFA NPs exhibited superior and specific anti-GBM activities, reduced off-target drug delivery, prolonged lifespan, and has negligible side effects in tumor-bearing mice. This study combines high-throughput drug screening with biomimetic nanodrug delivery system technology to provide a theoretical and practical basis for drug development and the optimization of clinical treatment strategies for GBM treatment.

Second Near-Infrared Macrophage-Biomimetic Nanoprobes for Photoacoustic Imaging of Neuroinflammation

Neuroinflammation is a significant pathological event involving the neurodegenerative process associated with many neurological disorders. Diagnosis and treatment of neuroinflammation in its early stage are essential for the prevention and management of neurological diseases. Herein, we designed macrophage membrane-coated photoacoustic (PA) probes (MSINPs), with targeting specificities based on naturally existing target-ligand interactions for the early diagnosis of neuroinflammation. The second near-infrared dye, IR1061, was doped into silica as the core and was encapsulated with a macrophage membrane. In vitro as well as in vivo, the MSINPs could target inflammatory cells via the inflammation chemotactic effect. PA imaging was used to trace the MSINPs in a neuroinflammation mouse model and showed a great targeted effect of MSINPs in the prefrontal cortex. Therefore, the biomimetic nanoprobe prepared in this study offers a new strategy for PA molecular imaging of neuroinflammation, which can enhance our understanding of the evolution of neuroinflammation in specific brain regions.

Hybrid Cellular Nanovesicles Block PD-L1 Signal and Repolarize M2 Macrophages for Cancer Immunotherapy

The PD1/PD-L1 immune checkpoint blocking is a promising therapy, while immunosuppressive tumor microenvironment (TME) and poor tumor penetration of therapeutic antibodies limit its efficacy. Repolarization of tumor-associated macrophages (TAMs) offers a potential method to ameliorate immunosuppression of TME and further boost T cell antitumor immunity. Herein, hybrid cell membrane biomimetic nanovesicles (hNVs) are developed by fusing M1 macrophage-derived nanovesicles (M1-NVs) and PD1-overexpressed tumor cell-derived nanovesicles (PD1-NVs) to improve cancer immunotherapy. The M1-NVs promote the transformation of M2-like TAMs to M1-like phenotype and further increase the release of pro-inflammatory cytokines, resulting in improved immunosuppressive TME. Concurrently, the PD1-NVs block PD1/PD-L1 pathway, which boosts cancer immunotherapy when combined with M1-NVs. In a breast cancer mouse model, the hNVs efficiently accumulate at the tumor site after intravenous injection and significantly inhibit the tumor growth. Mechanically, the M1 macrophages and CD8+ T lymphocytes in TME increase by twofold after the treatment, indicating effective immune activation. These results suggest the hNVs as a promising strategy to integrate TME improvement with PD1/PD-L1 blockade for cancer immunotherapy.

Platelet Membrane-Encapsulated Nanocomplexes Based on Profundity Scavenging ROS Strategy for Myocardial Infarction Therapy

Ischemia-induced myocardial injury has become a serious threat to human health, and its treatment remains a challenge. The occurrence of ischemic events leads to a burst release of reactive oxygen species (ROS), which triggers extensive oxidative damage and leads to dysfunctional autophagy, making it difficult for cells to maintain homeostasis. Antioxidants and modulation of autophagy have thus become promising strategies for the treatment of ischemic myocardial injury. This study proposes an antioxidant-activated autophagy therapeutic regimen based on combining melanin (Mel), an excellent antioxidant with metformin mimetic ploymetformin via electrostatic interactions, to obtain a nanocomplex (Met-Mel). The nanocomplex is finally encapsulated with platelet membranes (PMN) to construct a biomimetic nanoparticle (PMN@Met-Mel) capable of targeting injured myocardium. The prepared PMN@Met-Mel has good Mel loading capacity and optimal biosafety. It exhibits excellent antioxidant activity and autophagy activation, rapidly restoring mitochondrial function. Moreover, RNA sequencing (RNA-seq) analysis reveals that PMN@Met-Mel operates mechanistically by triggering the activation of the autophagy pathway. Subsequent in vivo experiments showcase promising cardioprotective effects of these nanoparticles. These discoveries present a newly devised nanoplatform with promising potential for the effective treatment of myocardial infarction.

Boosting Microglial Lipid Metabolism via TREM2 Signaling by Biomimetic Nanoparticles to Attenuate the Sevoflurane-Induced Developmental Neurotoxicity

Lipid metabolism has been considered as a potential therapeutic target in sevoflurane-induced neurotoxicity that can potentially affect the learning and memory function in the developmental brain. Recently, triggering receptor expressed on myeloid cells 2 (TREM2) is identified as a crucial step in regulating lipid metabolism and associated with the pathogenesis of neurodegenerative diseases. Herein, it is reported that quercetin modified Cu2- x Se (abbreviated as CSPQ) nanoparticles can ameliorate sevoflurane-induced neurotoxicity by tuning the microglial lipid metabolism and promoting microglial M2-like polarization via TREM2 signaling pathway, in which the apolipoprotein E (ApoE), and adenosine triphosphate-binding cassette transporters (ABCA1 and ABCG1) levels are upregulated. Furthermore, the protective effects of CSPQ nanoparticles against sevoflurane-induced neurotoxicity via TREM2 are further demonstrated by the small interfering RNA (siRNA)-TREM2 transfected BV2 cells, which are obviously not influenced by CSPQ nanoparticles. The cell membrane coated CSPQ (referred as CSPQ@CM) nanoparticles can significantly reduce sevoflurane-induced learning and memory deficits, improve lipid metabolism dysfunction, and promote the remyelination in the hippocampus of mice. The study shows great potential of targeting microglial lipid metabolism in promoting remyelination of neurons for treatment of neurotoxicity and neurodegenerative diseases.

Aggregation-Induced Emission-Based Macrophage-Like Nanoparticles for Targeted Photothermal Therapy and Virus Transmission Blockage in Monkeypox

The recent prevalence of monkeypox has led to the declaration of a Public Health Emergency of International Concern. Monkeypox lesions are typically ulcers or pustules (containing high titers of replication-competent virus) in the skin and mucous membranes, which allow monkeypox virus to transmit predominantly through intimate contact. Currently, effective clinical treatments for monkeypox are lacking, and strategies for blocking virus transmission are fraught with drawbacks. Herein, this work constructs a biomimetic nanotemplate (termed TBD@M NPs) with macrophage membranes as the coat and polymeric nanoparticles loading a versatile aggregation-induced emission featured photothermal molecule TPE-BT-DPTQ as the core. In a surrogate mouse model of monkeypox (vaccinia-virus-infected tail scarification model), intravenously injected TBD@M NPs show precise tracking and near-infrared region II fluorescence imaging of the lesions. Upon 808 nm laser irradiation, the virus is eliminated by the photothermal effect and the infected wound heals rapidly. More importantly, the inoculation of treated lesion tissue suspensions does not trigger tail infection or inflammatory activation in healthy mice, indicating successful blockage of virus transmission. This study demonstrates for the first time monkeypox theranostics using nanomedicine, and may bring a new insight into the development of a viable strategy for monkeypox management in clinical trials.

Orchestrating Precision within the Tumor Microenvironment by Biomimetic Nanoprodrugs for Effective Tumor Therapy

Malignant tumors are still one of the most deadly diseases that threaten human life and health. However, developing new drugs is challenging due to lengthy trials, funding constraints, and regulatory approval procedures. Consequently, researchers have devoted themselves to transforming some clinically approved old drugs into antitumor drugs with certain active ingredients, which have become an attractive alternative. Disulfiram (DSF), an antialcohol medication, can rapidly metabolize in the physiological environment into diethyldithiocarbamate (DTC) which can readily react with Cu2+ ions in situ to form the highly toxic bis(N,N-diethyldithiocarbamate)-copper(II) (CuET) complex. In this study, DSF is loaded into mesoporous dopamine nanocarriers and surface-chelated with tannin and Cu2+ to construct M-MDTC nanoprodrugs under the camouflage of K7 tumor cell membranes. After intravenous injection, M-MDTC nanoprodrugs successfully reach the tumor sites with the help of mediated cell membranes. Under slightly acidic pH and photothermal stimulation conditions, DSF and Cu2+ are simultaneously released, forming a highly toxic CuET to kill tumor cells in situ. The generated CuET can also induce immunogenic cell death of tumor cells, increase the proportion of CD86+ CD80+ cells, and promote dendritic cell maturation. In vitro and in vivo studies of M-MDTC nanoprodrugs have shown excellent tumor-cell-killing ability and solid tumor suppression. This approach enables in situ amplification of chemotherapy in the tumor microenvironment, achieving an effective antitumor treatment.

Targeted Delivery of Peptide Nucleic Acid by Biomimetic Nanoparticles Based on Extracellular Vesicle-coated Mesoporous Silica Nanoparticles

BACKGROUND

Peptide nucleic acid (PNA) plays an important role in antimicrobial activity, but its cellular permeability is poor. To overcome this limitation, we constructed biomimetic nanoparticles by using extracellular vesicle (EV)-coated mesoporous silicon nanoparticles (MSNs) to deliver PNA to Staphylococcus aureus (S. aureus) and improve its antisense therapeutic effect.

METHOD

MSN was prepared by the sol-gel method, and EV was extracted by affinity resin chromatography. EV was coated on MSN by simple sonication (50 W, 3 min) to prepare biomimetic nanoparticles with PNA-loaded MSN as the core and EV isolated from S. aureus as the shell.

RESULTS

The MSN prepared by the sol-gel method had a uniform particle size (100 nm) and well-defined pore size for loading PNA with good encapsulation efficiency (62.92%) and drug loading (7.74%). The concentration of EV extracted by affinity resin chromatography was about 1.74 mg/mL. EV could be well coated on MSN through simple ultrasonic treatment (50 W, 3 min), and the stability and blood compatibility of MSN@ EV were good. Internalization experiments showed that EV could selectively enhance the uptake of biomimetic nanoparticles by S. aureus. Preliminary in vitro antibacterial tests revealed that PNA@MSN@EV exhibited enhanced antibacterial activity against S. aureus and had stronger bactericidal activity than free PNA and PNA@MSN at equivalent PNA concentrations (8 μM).

CONCLUSION

Biomimetic nanoparticles based on EV-coated MSN offer a new strategy to improve the efficacy of PNA for the treatment of bacterial infections, and the technology holds promise for extension to the delivery of antibiotics that are traditionally minimally effective or prone to resistance.

Biomimetic Nanocarriers of Pro-Resolving Lipid Mediators for Resolution of Inflammation in Atherosclerosis

Atherosclerosis (ATH) is a systemic disease characterized by a chronic inflammatory process and lipid deposition in the arterial walls. The chronic inflammation within ATH lesions results, at least in part, from the failed resolution of inflammation. This process is controlled actively by specialized pro-resolving lipid mediators (SPMs), namely lipoxins, resolvins, protectins, and maresins. Herein, biomimetic nanocarriers are produced comprising a cocktail of SPMs-loaded lipid nanoemulsions (LN) covered with macrophage membranes (Bio-LN/SPMs). Bio-LN/SPMs retain on their surface the macrophage receptors involved in cellular interactions and the "marker of self" CD47, which impede their recognition and uptake by other macrophages. The binding of Bio-LN/SPMs to the surface of endothelial cells (EC) and smooth muscle cells (SMC) is facilitated by the receptors on the macrophage membranes and partly by SPMs receptors. In addition, Bio-LN/SPMs prove functional by reducing monocyte adhesion and transmigration to/through activated EC and by stimulating macrophage phagocytic activity. After intravenous administration, Bio-LN/SPMs accumulate in the aorta of ApoE-deficient mice at the level of atherosclerotic lesions. Also, the safety assessment testing reveals no side effects or immunotoxicity of Bio-LN/SPMs. Thus, the newly developed Bio-LN/SPMs represent a reliable targeted nanomedicine for the resolution of inflammation in atherosclerosis.

Cytoplasmic Escape of Mitochondrial DNA Mediated by Mfn2 Downregulation Promotes Microglial Activation via cGas-Sting Axis in Spinal Cord Injury

Neuroinflammation is associated with poor outcomes in patients with spinal cord injury (SCI). Recent studies have demonstrated that stimulator of interferon genes (Sting) plays a key role in inflammatory diseases. However, the role of Sting in SCI remains unclear. In the present study, it is found that increased Sting expression is mainly derived from activated microglia after SCI. Interestingly, knockout of Sting in microglia can improve the recovery of neurological function after SCI. Microglial Sting knockout restrains the polarization of microglia toward the M1 phenotype and alleviates neuronal death. Furthermore, it is found that the downregulation of mitofusin 2 (Mfn2) expression in microglial cells leads to an imbalance in mitochondrial fusion and division, inducing the release of mitochondrial DNA (mtDNA), which mediates the activation of the cGas-Sting signaling pathway and aggravates inflammatory response damage after SCI. A biomimetic microglial nanoparticle strategy to deliver MASM7 (named MSNs-MASM7@MI) is established. In vitro, MSNs-MASM7@MI showed no biological toxicity and effectively delivered MASM7. In vivo, MSNs-MASM7@MI improves nerve function after SCI. The study provides evidence that cGas-Sting signaling senses Mfn2-dependent mtDNA release and that its activation may play a key role in SCI. These findings provide new perspectives and potential therapeutic targets for SCI treatment.

Biomimetic Copper-Doped Polypyrrole Nanoparticles for Enhanced Cancer Low-Temperature Photothermal Therapy

Introduction

Photothermal therapy (PTT) has a significant potential for its application in precision tumour therapy. However, PTT-induced hyperthermia may damage healthy tissues and trigger the expression of heat shock proteins (HSPs), thereby compromising the long-term therapeutic efficacy of PTT.

Methods

In this study, a biomimetic drug delivery system comprising CuP nanozymes as the inner core and platelet membrane (PM) as the outer shell was successfully developed for administering synergistic chemodynamic therapy and mild PTT. PM is encapsulated on CuP to form this biomimetic nanoparticle (PM-coated CuP nanoparticles, PC). PC possesses peroxidase (POD) activity, can facilitate the conversion of hydrogen peroxide into ·OH, thereby inhibiting the expression of HSPs.

Results

Upon exposure to low-power laser irradiation (0.5 W/cm2, 1064 nm), PC can convert near-infrared II laser energy into heat energy, thereby enabling the administration of enhanced mild PTT. In vitro and in vivo experiments have demonstrated that this synergistic approach can induce over 90% tumour eradication with favourable biocompatibility.

Discussion

PC exhibits high efficacy and biocompatibility, making it a promising candidate for future applications.

Neuroprotective Effects of Microglial Membrane-Derived Biomimetic Particles for Spinal Cord Injury

Inhibition of oxidative stress and inflammatory responses caused by secondary injury following traumatic spinal cord injury (SCI) is an attractive strategy in treating traumatic SCI. However, the efficacy of drugs is severely limited owing to the poor penetration of the blood spinal cord barrier (BSCB). Here, inspired by cell chemotaxis and related chemokines production at the lesion sites of SCI, the microglial membrane is selected to construct a drug delivery system with the ability to cross the BSCB and target the lesions. PR@MM is prepared based on the assembly of polylactic-co-glycolic acid (PLGA) and resveratrol (RSV) followed by microglial membrane (MM) coating. Compared to that of the uncoated nanoparticles, the enrichment of PR@MM at the lesion sites of SCI increases, which is beneficial to achieve lesion targeting of RSV and exert therapeutic functions. Both in vitro and in vivo experiments demonstrate that PR@MM has the ability to scavenge reactive oxygen species and anti-inflammatory effects, which ultimately promotes the recovery of locomotory function after SCI. Therefore, this microglial membrane-based drug delivery system provides a promising biomimetic nanomedicine for targeted therapy for SCI.

Transient inhibition of lysosomal functions potentiates nucleic acid vaccines

Nucleic acid vaccines have shown promising results in the clinic against infectious diseases and cancers. To robustly improve the vaccine efficacy and safety, we developed an approach to increase the intracellular stability of nucleic acids by transiently inhibiting lysosomal function in targeted tissues using sucrose. To achieve efficient and localized delivery of sucrose in animals, we designed a biomimetic lipid nanoparticle (LNP) to target the delivery of sucrose into mouse muscle cells. Using this approach, viral antigen expression in mouse muscle after DNA vaccination was substantially increased and prolonged without inducing local or systemic inflammation or toxicity. The same change in antigen expression would be achieved if the vaccine dose could be increased by 3,000 folds, which is experimentally and clinically impractical due to material restrictions and severe toxicity that will be induced by such a high dose of nucleic acids. The increase in antigen expression augmented the infiltration and activation of antigen-presenting cells, significantly improved vaccine-elicited humoral and T cell responses, and fully protected mice against the viral challenge at a low dose of vaccine. Based on these observations, we conclude that transient inhibition of lysosome function in target tissue by sucrose LNPs is a safe and potent approach to substantially improve nucleic acid-based vaccines.

Recent Advances in Biomimetic Nanocarrier-Based Photothermal Therapy for Cancer Treatment

Nanomedicine presents innovative solutions for cancer treatment, including photothermal therapy (PTT). PTT centers on the design of photoactivatable nanoparticles capable of absorbing non-toxic near-infrared light, generating heat within target cells to induce cell death. The successful transition from benchside to bedside application of PTT critically depends on the core properties of nanoparticles responsible for converting light into heat and the surface properties for precise cell-specific targeting. Precisely targeting the intended cells remains a primary challenge in PTT. In recent years, a groundbreaking approach has emerged to address this challenge by functionalizing nanocarriers and enhancing cell targeting. This strategy involves the creation of biomimetic nanoparticles that combine desired biocompatibility properties with the immune evasion mechanisms of natural materials. This review comprehensively outlines various strategies for designing biomimetic photoactivatable nanocarriers for PTT, with a primary focus on its application in cancer therapy. Additionally, we shed light on the hurdles involved in translating PTT from research to clinical practice, along with an overview of current clinical applications.

Lipidic Formulations Inspired by COVID Vaccines as Smart Coatings to Enhance Nanoparticle-Based Cancer Therapy

Recent advances in nanomedicine have led to the introduction and subsequent establishment of nanoparticles in cancer treatment and diagnosis. Nonetheless, their application is still hindered by a series of challenges related to their biocompatibility and biodistribution. In this paper, we take inspiration from the recently produced and widely spread COVID vaccines, based on the combinational use of ionizable solid lipid nanoparticles, cholesterol, PEGylated lipids, and neutral lipids able to incorporate mRNA fragments. Here, we focus on the implementation of a lipidic formulation meant to be used as a smart coating of solid-state nanoparticles. The composition of this formulation is finely tuned to ensure efficient and stable shielding of the cargo. The resulting shell is a highly customized tool that enables the possibility of further functionalizations with targeting agents, peptides, antibodies, and fluorescent moieties for future in vitro and in vivo tests and validations. Finally, as a proof of concept, zinc oxide nanoparticles doped with iron and successively coated with this lipidic formulation are tested in a pancreatic cancer cell line, BxPC-3. The results show an astonishing increase in cell viability with respect to the same uncoated nanoparticles. The preliminary results presented here pave the way towards many different therapeutic approaches based on the massive presence of highly biostable and well-tolerated nanoparticles in tumor tissues, such as sonodynamic therapy, photodynamic therapy, hyperthermia, and diagnosis by means of magnetic resonance imaging.

Immunostimulatory DNA Hydrogel Enhances Protective Efficacy of Nanotoxoids against Bacterial Infection

While vaccines have been highly successful in protecting against various infections, there are still many high-priority pathogens for which there are no clinically approved formulations. To overcome this challenge, researchers have explored the use of nanoparticulate strategies for more effective antigen delivery to the immune system. Along these lines, nanotoxoids are a promising biomimetic platform that leverages cell membrane coating technology to safely deliver otherwise toxic bacterial antigens in their native form for antivirulence vaccination. Here, in order to further boost their immunogenicity, nanotoxoids formulated against staphylococcal α-hemolysin are embedded into a DNA-based hydrogel with immunostimulatory CpG motifs. The resulting nanoparticle-hydrogel composite is injectable and improves the in vivo delivery of vaccine antigens while simultaneously stimulating nearby immune cells. This leads to elevated antibody production and stronger antigen-specific cellular immune responses. In murine models of pneumonia and skin infection caused by methicillin-resistant Staphylococcus aureus, mice vaccinated with the hybrid vaccine formulation are well-protected. This work highlights the benefits of combining nanoparticulate antigen delivery systems with immunostimulatory hydrogels into a single platform, and the approach can be readily generalized to a wide range of infectious diseases.

Biomimetic Cell-Derived Nanoparticles: Emerging Platforms for Cancer Immunotherapy

Cancer immunotherapy can significantly prevent tumor growth and metastasis by activating the autoimmune system without destroying normal cells. Although cancer immunotherapy has made some achievements in clinical cancer treatment, it is still restricted by systemic immunotoxicity, immune cell dysfunction, cancer heterogeneity, and the immunosuppressive tumor microenvironment (ITME). Biomimetic cell-derived nanoparticles are attracting considerable interest due to their better biocompatibility and lower immunogenicity. Moreover, biomimetic cell-derived nanoparticles can achieve different preferred biological effects due to their inherent abundant source cell-relevant functions. This review summarizes the latest developments in biomimetic cell-derived nanoparticles for cancer immunotherapy, discusses the applications of each biomimetic system in cancer immunotherapy, and analyzes the challenges for clinical transformation.

A Stepwise Targeting and Antibacterial Strategy by Leukocyte Membrane-Based Conjugated Oligomer Nanoparticles

Bacterial infection poses an enormous threat to human life and health. The inability of drugs to be effectively delivered to the site of infection and the development of bacterial resistance make the treatment process more difficult. Herein, a stepwise targeted biomimetic nanoparticle (NPs@M-P) with inflammatory tendency and Gram-negative bacterial targeting was designed, which can achieve efficient antibacterial activity under near-infrared triggering. Leukocyte membranes and targeted molecules (PMB) are used to deliver NPs to the surface of Gram-negative bacteria. The heat and ROS released by NPs@M-P can efficiently kill Gram-negative bacteria under low-power near-infrared light. Thus, this multimodal combination therapy strategy has broad promise in fighting bacterial infection and avoiding drug resistance.

Mesenchymal Stem Cell Membrane-Coated TPCS2a-Loaded Nanoparticles for Breast Cancer Photodynamic Therapy

Despite substantial improvements in breast cancer (BC) treatment there is still an urgent need to find alternative treatment options to improve the outcomes for patients with advanced-stage disease. Photodynamic therapy (PDT) is gaining a lot of attention as a BC therapeutic option because of its selectivity and low off-target effects. However, the hydrophobicity of photosensitizers (PSs) impairs their solubility and limits the circulation in the bloodstream, thus representing a major challenge. The use of polymeric nanoparticles (NPs) to encapsulate the PS may represent a valuable strategy to overcome these issues. Herein, we developed a novel biomimetic PDT nanoplatform (NPs) based on a polymeric core of poly(lactic-co-glycolic)acid (PLGA) loaded with the PS meso-tetraphenylchlorin disulfonate (TPCS_2a). TPCS_2a@NPs of 98.89 ± 18.56 nm with an encapsulation efficiency percentage (EE%) of 81.9 ± 7.92% were obtained and coated with mesenchymal stem cells-derived plasma membranes (mMSCs) (mMSC-TPCS_2a@NPs, size of 139.31 ± 12.94 nm). The mMSC coating armed NPs with biomimetic features to impart long circulation times and tumor-homing capabilities. In vitro, biomimetic mMSC-TPCS_2a@NPs showed a decrease in macrophage uptake of 54% to 70%, depending on the conditions applied, as compared to uncoated TPCS_2a@NPs. Both NP formulations efficiently accumulated in MCF7 and MDA-MB-231 BC cells, while the uptake was significantly lower in normal breast epithelial MCF10A cells with respect to tumor cells. Moreover, encapsulation of TPCS_2a in mMSC-TPCS_2a@NPs effectively prevents its aggregation, ensuring efficient singlet oxygen (¹O₂) production after red light irradiation, which resulted in a considerable in vitro anticancer effect in both BC cell monolayers (IC₅₀ < 0.15 µM) and three-dimensional spheroids.

Ameliorating Mitochondrial Dysfunction of Neurons by Biomimetic Targeting Nanoparticles Mediated Mitochondrial Biogenesis to Boost the Therapy of Parkinson's Disease

Mitochondrial dysfunction of neurons is the core pathogenesis of incurable Parkinson's disease (PD). It is crucial to ameliorate the mitochondrial dysfunction of neurons for boosting the therapy of PD. Herein, the remarkable promotion of mitochondrial biogenesis to ameliorate mitochondrial dysfunction of neurons and improve the treatment of PD by using mitochondria-targeted biomimetic nanoparticles, which are Cu_{2- x} Se-based nanoparticles functionalized with curcumin and wrapped with DSPE-PEG₂₀₀₀ -TPP-modified macrophage membrane (denoted as CSCCT NPs), is reported. These nanoparticles can efficiently target mitochondria of damaged neurons in an inflammatory environment, and mediate the signaling pathway of NAD⁺ /SIRT1/PGC-1α/PPARγ/NRF1/TFAM to alleviate 1-methyl-4-phenylpyridinium (MPP⁺ )-induced neuronal toxicity. They can reduce the mitochondrial reactive oxygen species, restore mitochondrial membrane potential (MMP), protect the integrity of mitochondrial respiratory chain, and ameliorate mitochondrial dysfunction via promoting mitochondrial biogenesis, which synergistically improve the motor disorders and anxiety behavior of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice. This study demonstrates that targeting mitochondrial biogenesis to ameliorate mitochondrial dysfunction has a great potential in the treatment of PD and mitochondria-related diseases.

Recent progress in therapeutic strategies and biomimetic nanomedicines based on neutrophils for inflammation treatment

Inflammation is a defensive response that helps repair and restore damaged tissue by activating immune and nonimmune cells against pathogens. However, inflammation may cause chronic disease if it persists for a long time. Neutrophils recruit immediately to the lesion site and regulate the inflammatory process when inflammation occurs. Therefore, neutrophil-mediated therapy has been considered as a promising strategy for inflammatory diseases and has been extensively studied. In this review, we summarize the recent research progress of neutrophil-based personalized treatment strategies for inflammation. We also review the research progress of various neutrophil-mediated drug-delivery systems in combination with the inflammatory microenvironment.

Phytochemicals and Cancer Treatment: Cell-Derived and Biomimetic Vesicles as Promising Carriers

The majority of anticancer agents currently used derive from natural sources: plants, frequently the ones employed in traditional medicines, are an abundant source of mono- and diterpenes, polyphenols, and alkaloids that exert antitumor activity through diverse mechanisms. Unfortunately, many of these molecules are affected by poor pharmacokinetics and limited specificity, shortcomings that may be overcome by incorporating them into nanovehicles. Cell-derived nanovesicles have recently risen to prominence, due to their biocompatibility, low immunogenicity and, above all, targeting properties. However, due to difficult scalability, the industrial production of biologically-derived vesicles and consequent application in clinics is difficult. As an efficient alternative, bioinspired vesicles deriving from the hybridization of cell-derived and artificial membranes have been conceived, revealing high flexibility and appropriate drug delivery ability. In this review, the most recent advances in the application of these vesicles to the targeted delivery of anticancer actives obtained from plants are presented, with specific focus on vehicle manufacture and characterization, and effectiveness evaluation performed through in vitro and in vivo assays. The emerging overall outlook appears promising in terms of efficient drug loading and selective targeting of tumor cells, suggesting further engrossing developments in the future.

Long Circulating Cancer Cell-Targeted Bionic Nanocarriers Enable Synergistic Combinatorial Therapy in Colon Cancer

Cancer nanomedicine treatment aims to achieve highly specific targeting and localization to cancer cells. Coating of nanoparticles with cell membranes endows them with homologous cellular mimicry, enabling nanoparticles to acquire new functions and properties, including homologous targeting and long circulation in vivo, and can enhance internalization by homologous cancer cells. Herein, we fused a human-derived HCT116 colon cancer cell membrane (cM) with a red blood cell membrane (rM) to fabricate an erythrocyte-cancer cell hybrid membrane (hM). Oxaliplatin and chlorin e6 (Ce6) co-encapsulated reactive oxygen species-responsive nanoparticles (NPOC) were camouflaged by hM and obtained a hybrid biomimetic nanomedicine (denoted as hNPOC) for colon cancer therapy. hNPOC exhibited prolonged circulation time and recognized homologous targeting ability in vivo since both rM and HCT116 cM proteins were maintained on the hNPOC surface. hNPOC showed enhanced homologous cell uptake in vitro and considerable homologous self-localization in vivo, producing effective synergistic chemophotodynamic therapy efficacy under irradiation with a homologous HCT116 tumor compared to that with a heterologous tumor. Together, the biomimetic hNPOC nanoparticles showed prolonged blood circulation and preferential cancer cell-targeted function in vivo to provide a bioinspired strategy for chemophotodynamic synergistic therapy of colon cancer.

Reversing T Cell Dysfunction to Boost Glioblastoma Immunotherapy by Paroxetine-Mediated GRK2 Inhibition and Blockade of Multiple Checkpoints through Biomimetic Nanoparticles

T cell dysfunction-induced tumor immune escape is particularly severe in glioblastoma (GBM), and significantly affects the efficacy of immunotherapy. It is crucial to innovatively reverse the T cell dysfunction for improving GBM immunotherapy. Herein, T cell dysfunction is remarkably reversed and immunotherapy of GBM is boosted by repurposing the U. S. Food and Drug Administration-approved antidepressant paroxetine (PX) with biomimetic nanoparticles (CS-J@CM/6 NPs). The PX is successfully applied to abrogate T cell sequestration in the bone marrow of GBM-bearing mice and increase their infiltration in tumor. The biomimetic NPs are composed of ultrasmall Cu_{2- x} Se NPs, JQ1, and tumor cell membrane modified with CD6, and are efficiently delivered into tumor through the specific interactions between CD6 and activated leukocyte cell adhesion molecule. They ameliorate the T cell dysfunction through the double roles of loaded JQ1, which simultaneously decreases the expression of PD-1 and TIM-3 on T cells, and the expression of PD-L1 on tumor cells. The NP also induces the immunogenic cell death of tumor cells to activate immune response. The synergistic roles of PX and biomimetic CS-J@CM/6 NPs notably enhance the survival of GBM-bearing mice. This work provides new insights into tumor immunotherapy by repurposing "old drugs" with advanced NPs.

Arsenic-Loaded Biomimetic Iron Oxide Nanoparticles for Enhanced Ferroptosis-Inducing Therapy of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) has a poor response to most available systemic therapies due to intrinsic or acquired resistance to apoptosis. Ferroptosis-based therapy is expected to circumvent those limitations. Therefore, the rational design of ferroptosis-based therapies with targeted delivery of ferroptosis inducers for HCC is in need. In this study, we found that arsenic trioxide (ATO) can efficiently induce ferroptosis in HCC cells, and this effect could be reversed by the iron chelator deferoxamine. On this basis, a drug delivery system was constructed to enhance the therapeutic efficacy of ATO by camouflaging ATO-loaded magnetic nanoparticles (Fe3O4) with HCC cell membranes, termed AFN@CM. After AFN@CM treatment, glutathione peroxidase 4 was strongly inhibited and intracellular lipid peroxide species were significantly increased in HCC cells. In addition, enhanced ferroptosis and tumor suppression were observed both in vitro and in vivo. The bio-safety of AFN@CM was also demonstrated by the in vivo toxicity evaluation. In addition, benefiting from the cell membrane coating, AFN@CM showed enhanced accumulation at tumor sites and achieved continuous tumor elimination in the mouse model. In conclusion, AFN@CM exhibited satisfactory therapeutic efficacy in the treatment of HCC and provided a desirable ferroptosis-based strategy for safe and reliable HCC therapeutics.

Genetically engineered cell membrane-coated nanoparticles for antibacterial and immunoregulatory dual-function treatment of ligature-induced periodontitis

Purpose: In order to overcome the problem that conventional pharmacological treatments of periodontitis cannot effectively synergizing antimicrobial and immunomodulation, inspired by the critical role of toll-like receptor 4 (TLR4) in bacterial recognition and immune activation, we demonstrated a combined antibacterial-immunoregulatory strategy based on biomimetic nanoparticles. Methods: Functioned cell membranes and silk fibroin nanoparticles (SNs) loaded with minocycline hydrochloride (Mino) were used to prepare a biomimetic nanoparticle (MSNCs). SNs and MSNCs were characterized by Scanning Electron Microscope, size, zeta potential, dispersion index. At the same time, SNs were characterized by cell counting kit-8 and real-time Polymerase Chain Reaction (RT-PCR). TLR4-expressing cell membranes were characterized by RT-PCR and western blot (WB). Cell membrane coating was characterized by Transmission Electron Microscope (TEM), the Bradford staining and WB. Then, Laser confocal, flow cytometry and agar plate coating were evaluated in vitro with antibacterial effects, RT-PCR was simultaneously evaluated with immunoregulatory effects. Finally, Anti-inflammatory treatment of MSNCs was evaluated in a ligature-induced periodontitis (LIP) mouse model. Results: Successfully prepared cell membranes overexpressing TLR4 and constructed MSNCs. In vitro studies had shown that MSNCs effectively targeted bacteria via TLR4 and acted as molecular decoys to competitively neutralize lipopolysaccharide (LPS) in the microenvironment as well as inhibit inflammatory activation of macrophages. In vivo, MSNCs effectively attenuated periodontal tissue inflammation and alveolar bone loss in a LIP mouse model. Conclusion: MSNCs have good targeted antibacterial and immunoregulatory effects, and provide a new and effective strategy for the treatment of periodontitis and have good potential for application in various types of pathogenic bacterial infections.

Recent advances of cell membrane-coated nanoparticles for therapy of bacterial infection

The rapid evolution of antibiotic resistance and the complicated bacterial infection microenvironments are serious obstacles to traditional antibiotic therapy. Developing novel antibacterial agents or strategy to prevent the occurrence of antibiotic resistance and enhance antibacterial efficiency is of the utmost importance. Cell membrane-coated nanoparticles (CM-NPs) combine the characteristics of the naturally occurring membranes with those of the synthetic core materials. CM-NPs have shown considerable promise in neutralizing toxins, evading clearance by the immune system, targeting specific bacteria, delivering antibiotics, achieving responsive antibiotic released to the microenvironments, and eradicating biofilms. Additionally, CM-NPs can be utilized in conjunction with photodynamic, sonodynamic, and photothermal therapies. In this review, the process for preparing CM-NPs is briefly described. We focus on the functions and the recent advances in applications of several types of CM-NPs in bacterial infection, including CM-NPs derived from red blood cells, white blood cells, platelet, bacteria. CM-NPs derived from other cells, such as dendritic cells, genetically engineered cells, gastric epithelial cells and plant-derived extracellular vesicles are introduced as well. Finally, we place a novel perspective on CM-NPs' applications in bacterial infection, and list the challenges encountered in this field from the preparation and application standpoint. We believe that advances in this technology will reduce threats posed by bacteria resistance and save lives from infectious diseases in the future.

Biomimetic nanoparticles for tumor immunotherapy

Currently, tumor treatment research still focuses on the cancer cells themselves, but the fact that the immune system plays an important role in inhibiting tumor development cannot be ignored. The activation of the immune system depends on the difference between self and non-self. Unfortunately, cancer is characterized by genetic changes in the host cells that lead to uncontrolled cell proliferation and evade immune surveillance. Cancer immunotherapy aims to coordinate a patient's immune system to target, fight, and destroy cancer cells without destroying the normal cells. Nevertheless, antitumor immunity driven by the autoimmune system alone may be inadequate for treatment. The development of drug delivery systems (DDS) based on nanoparticles can not only promote immunotherapy but also improve the immunosuppressive tumor microenvironment (ITM), which provides promising strategies for cancer treatment. However, conventional nano drug delivery systems (NDDS) are subject to several limitations in clinical transformation, such as immunogenicity and the potential toxicity risks of the carrier materials, premature drug leakage at off-target sites during circulation and drug load content. In order to address these limitations, this paper reviews the trends and progress of biomimetic NDDS and discusses the applications of each biomimetic system in tumor immunotherapy. Furthermore, we review the various combination immunotherapies based on biomimetic NDDS and key considerations for clinical transformation.

A Macrophage Membrane-Polymer Hybrid Biomimetic Nanoplatform for Therapeutic Delivery of Somatostatin Peptide to Chronic Pancreatitis

The clinical translation of therapeutic peptides is generally challenged by multiple issues involving absorption, distribution, metabolism and excretion. In this study, a macrophage membrane-coated poly(lactic-co-glycolic acid) (PLGA) nanodelivery system was developed to enhance the bioavailability of the somatostatin (SST) peptide, which faces the hurdles of short half-life and potential side effects in the treatment of chronic pancreatitis. Using a facile nanoprecipitation strategy, SST was loaded in the nanoparticles with an encapsulation efficiency (EE) and a loading efficiency (LE) of 73.68 ± 3.56% and 1.47 ± 0.07%, respectively. The final formulation of SST-loaded nanoparticles with the camouflage of macrophage membrane (MP-SST) showed a mean diameter of 151 ± 4 nm and an average zeta potential of −29.6 ± 0.3 mV, which were stable long term during storage. With an above 90% cell viability, a hemolysis level of about 2% (<5%) and a preference for being ingested by activated endothelial cells compared to macrophages, the membrane−polymer hybrid nanoparticle showed biocompatibility and targeting capability in vitro. After being intravenously administered to mice with chronic pancreatitis, the MP-SST increased the content of SST in the serum (123.6 ± 13.6 pg/mL) and pancreas (1144.9 ± 206.2 pg/g) compared to the treatment of (Dulbecco’s phosphate-buffered saline) DPBS (61.7 ± 6.0 pg/mL in serum and 740.2 ± 172.4 pg/g in the pancreas). The recovery of SST by MP-SST downregulated the expressions of chronic pancreatitis-related factors and alleviated the histologic severity of the pancreas to the greatest extent compared to other treatment groups. This augmentation of SST therapeutic effects demonstrated the superiority of integrating the synthetic polymer with biological membranes in the design of nanoplatforms for advanced and smart peptide delivery. Other peptides like SST can also be delivered via the membrane−polymer hybrid nanosystem for the treatment of diseases, broadening and promoting the potential clinical applications of peptides as therapeutics.

Photoacoustic image-guided biomimetic nanoparticles targeting rheumatoid arthritis

The high level of reactive oxygen species (ROS) in the rheumatoid arthritis (RA) microenvironment (RAM) and its persistent inflammatory nature can promote damage to joints, bones, and the synovium. Targeting strategies that integrate effective RAM regulation with imaging-based monitoring could lead to improvements in the diagnosis and treatment of RA. Here, we report the combined use of small interfering RNAs (siRNAs^T/I) and Prussian blue nanoparticles (PBNPs) to silence the expression of proinflammatory cytokines TNF-α/IL-6 and scavenge the ROS associated with RAM. To enhance the in vitro and in vivo biological stability, biocompatibility, and targeting capability of the siRNAs^T/I and PBNPs, macrophage membrane vesicles were used to prepare biomimetic nanoparticles, M@P-siRNAs^T/I. The resulting constructs were found to suppress tumor necrosis factor-α/interleukin-6 expression and overcome the hypoxic nature of RAM, thus alleviating RA-induced joint damage in a mouse model. The M@P-siRNAs^T/I of this study could be monitored via near-infrared photoacoustic (PA) imaging. Moreover, multispectral PA imaging without the need for labeling permitted the real-time evaluation of M@P-siRNAs^T/I as a putative RA treatment. Clinical microcomputed tomography and histological analysis confirmed the effectiveness of the treatment. We thus suggest that macrophage-biomimetic M@P-siRNAs^T/I and their analogs assisted by PA imaging could provide a new strategy for RA diagnosis, treatment, and monitoring.

Macrophage-Membrane-Camouflaged Nonviral Gene Vectors for the Treatment of Multidrug-Resistant Bacterial Sepsis

Sepsis is a life-threatening disease caused by systemic bacterial infections, with high morbidity and mortality worldwide. As the standard treatment for sepsis, antibiotic therapy faces the challenge of impaired macrophages and drug-resistant bacteria. In this study, we developed a membrane-camouflaged metal-organic framework (MOF) system for plasmid DNA (pDNA) delivery to combat sepsis. The antimicrobial gene LL37 was efficiently encapsulated in the pH-sensitive MOF, and the nanoparticles were decorated with macrophage membranes in a compatible manner. Macrophage membrane coating allows targeted delivery of LL37 to macrophages and creates macrophage factories for the continuous generation of antimicrobial peptides. Compared to naked nanoparticles, primary bone marrow mesenchymal macrophage membrane-modified nanoparticles greatly improved the survival rate of immunodeficient septic mice through the synergistic effect of efficient gene therapy and inflammatory cytokine sequestration. This study demonstrates an effective membrane biomimetic strategy for efficiently delivering pDNA, offering an excellent option for overcoming sepsis.

Nanomedicines in oral cancer: inspiration comes from extracellular vesicles and biomimetic nanoparticles

Oral cancer is a common life-threatening malignancy having high mortality and morbidity rates. During the treatment process, individuals unavoidably experience severe side effects. It is essential to develop safer and more effective strategies. Currently, extracellular vesicles (EVs) and biomimetic nanoparticles are nanomedicines with long-term blood circulation and lower off-target toxicity that orchestrate immune responses and accumulate specifically in tumor sites. EVs create a synergetic effect by encapsulating drugs and collaborating with naturally loaded elements in the EVs. Biomimetic nanoparticles retain the characteristic features of the synthetic nanocarriers and inherit the intrinsic cell membrane functionalities. This review outlines the properties, applications, challenges, pros and cons of EVs and biomimetic nanoparticles, providing novel perspectives on oral cancer.

Coating a Self-Assembly Nanoconstruct with a Neutrophil Cell Membrane Enables High Specificity for Triple Negative Breast Cancer Treatment

Breast cancer is one of the most commonly diagnosed cancers in American women. Triple negative breast cancer is among the most advanced and aggressive forms of breast cancer. Treatment options are limited for such cancers, making chemotherapy a convenient and effective treatment. Although these therapies can reduce morbidity and mortality, it is often followed by systemic side effects or relapse. Nanoparticles (NPs) have been considered for drug delivery approaches due to their ability to target various disease sites. Herein, we aim to develop a biomimetic NP construct (cell membrane-cloaked NPs) that exhibits specific affinity with triple negative breast cancer cells. In this regard, we designed biomimetic supramolecular nanoconstructs composed of a poly(vinyl pyrrolidone)-tannic acid (PVP-TA NPs/ PVT NPs) core and biofunctionalized with neutrophil cell membranes (PVT-NEU NPs). In this study, we have synthesized a PVT-NEU NP construct, characterized it, and evaluated it for improved targeting and therapeutic benefits in in vitro and in vivo models. Analysis of PVT-NEU NPs confirms the presence of the core of PVP-TA NPs coated with activated human neutrophil membranes. The study results confirmed that PVT-NEU NPs demonstrated an enhanced interaction and targeting with the tumor cells, thus improving the therapeutic activity of a model therapeutic agent (paclitaxel). Altogether, this study suggests the potential of biomimetic NPs as a promising therapeutic option for targeted drug delivery for advanced-stage breast cancer and other similar diseased conditions.

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.

Macrophage Cell Membrane-Cloaked Nanoplatforms for Biomedical Applications

Biomimetic approaches utilize natural cell membrane-derived nanovesicles to camouflage nanoparticles to circumvent some limitations of nanoscale materials. This emergent cell membrane-coating technology is inspired by naturally occurring intercellular interactions, to efficiently guide nanostructures to the desired locations, thereby increasing both therapeutic efficacy and safety. In addition, the intrinsic biocompatibility of cell membranes allows the crossing of biological barriers and avoids elimination by the immune system. This results in enhanced blood circulation time and lower toxicity in vivo. Macrophages are the major phagocytic cells of the innate immune system. They are equipped with a complex repertoire of surface receptors, enabling them to respond to biological signals, and to exhibit a natural tropism to inflammatory sites and tumorous tissues. Macrophage cell membrane-functionalized nanosystems are designed to combine the advantages of both macrophages and nanomaterials, improving the ability of those nanosystems to reach target sites. Recent studies have demonstrated the potential of these biomimetic nanosystems for targeted delivery of drugs and imaging agents to tumors, inflammatory, and infected sites. The present review covers the preparation and biomedical applications of macrophage cell membrane-coated nanosystems. Challenges and future perspectives in the development of these membrane-coated nanosystems are addressed.

B16F10 Cell Membrane-Based Nanovesicles for Melanoma Therapy Are Superior to Hyaluronic Acid-Modified Nanocarriers

Some cancer cell membrane (CCM)-derived nanovesicles show strong homing effects and are used for targeted cancer therapy. By co-constructing the B16F10 cell membrane with a PEGylated phospholipid membrane, a new nanocarrier with a composite nanocrown structure was developed, which can evade immune recognition and actively target homologous melanoma. The nanocrowns have an encapsulation efficiency of more than 90% for paclitaxel and showed no significant difference (p > 0.05) from the PEGylated phospholipid membrane vesicles. Compared with the hyaluronic acid-modified PEGylated phospholipid membrane vesicles, the biomimetic nanocrowns enhanced the escape of nanovesicles from reticuloendothelial cells in vitro and extended the circulation time in vivo; moreover, the nanocrowns showed superior melanoma-targeted drug delivery capability and improved anticancer effects of paclitaxel as demonstrated by the inhibition of B16F10 cell proliferation and induction of apoptosis by interfering with microtubule formation. In contrast, the modification of hyaluronic acid did not increase the targeting capacity or antitumor effects of the nanocrowns, confirming that the superior targeting capacity was mediated by the exposed homologous CCMs rather than by hyaluronic acid. Our results demonstrate the potential of using biomimetic nanocrowns for active melanoma-targeted therapy.

DNA Base Pairing-Inspired Supramolecular Nanodrug Camouflaged by Cancer-Cell Membrane for Osteosarcoma Treatment

Osteosarcoma (OS) is one of the most common bone malignant tumors which mainly develops in adolescents. Although neoadjuvant chemotherapy has improved the prognosis of patients, numerous chemotherapeutic challenges still limit their use. Here, inspired by the Watson-Crick base pairing in nucleic acids, hydrophobic (methotrexate) and hydrophilic (floxuridine) chemo-drugs are mixed and self-assembled into M:F nanoparticles (M:F NPs) through molecular recognition. Then, the obtained NPs are co-extruded with membranes derived from OS cells to form cancer-cell membrane-coated NPs (CCNPs). With protected membranes at the outer layer, CCNPs are highly stable in both physiological and weak acid tumor conditions and possess homologous tumor targeted capability. Furthermore, the proteomic analysis first identifies over 400 proteins reserved in CCNPs, most of them participating in tumor cell targeting and adhesion processes. In vitro studies reveal that CCNPs significantly inhibit the PI3K/AKT/mTOR pathway, which promotes cell apoptosis and cell cycle arrest. More importantly, cell membrane camouflage significantly prolongs the circulation half-life of CCNPs, elevates the drug accumulation at tumor sites, and promotes anti-tumor efficacy in vivo. As a convenient and effective strategy to construct a biomimetic NP with high drug loading ratio, the CCNPs provide new potentials for precise and synergistic antitumor treatment.

Metabolic Reprogramming by Dual-targeting Biomimetic Nanoparticles for Enhanced Tumor Chemo-Immunotherapy

Cancer-associated fibroblasts (CAFs)-mediated metabolic support plays a vital role in tumorigenesis. The metabolic network between cancer cells and CAFs may serve as promising targets for cancer therapy. Here, aiming at targeted blockade of the metabolic support of CAFs to cancer cells, a biomimetic nanocarrier is designed by coating solid lipid nanoparticles containing chemotherapeutic paclitaxel (PTX) and glycolysis inhibitor PFK15 with hybrid membranes of cancer cells and activated fibroblasts. The nanoparticles possess outstanding dual-targeting ability which can simultaneously target cancer cells and CAFs. The encapsulated glycolysis inhibitor PFK15 can prevent the glycolysis of cancer cells and CAFs at the same time, thus increasing the chemosensitivity of cancer cells and blocking the metabolic support of CAFs to cancer cells. The results showed that the combination of PTX and PFK15 exhibited synergistic effects and inhibited tumor growth effectively. Moreover, the biomimetic nanoparticles obviously reduced the lactate production in the tumor microenvironment, leading to activated immune responses and enhanced tumor suppression. This work presents a facile strategy to destroy the metabolic network between cancer cells and CAFs, and proves the potential to elevate chemo-immunotherapy by glycolysis inhibition. STATEMENT OF SIGNIFICANCE: : In many solid tumors, most cancer cells produce energy and carry out biosynthesis through glycolysis, even in aerobic conditions. As the main tumor stromal cells, cancer-associated fibroblasts (CAFs) usually turn oxidative phosphorylation into aerobic glycolysis with metabolic reprogramming and provide high-energy glycolytic metabolites for cancer cells. The metabolic network between cancer cells and CAFs is regarded as the vulnerability among cancer cells. Moreover, lactate produced by cancer cells and CAFs through glycolysis often leads to the immunosuppressive tumor microenvironment. The present study provides an effective approach to destroy the metabolic network between cancer cells and CAFs and greatly improves the antitumor immune response by reducing lactate production, which serves as a promising strategy for combined chemo-immunotherapy mediated by glycolysis.

Biomimetic Nanoparticles Enabled by Cascade Cell Membrane Coating for Direct Cross-Priming of T Cells

Despite the activation of T lymphocytes by antigen-presenting cells being responsible for eliciting antigen-specific immune responses, their crosstalking suffers from temporospatial limitations and endogenous influencing factors, which restrict the generation of a strong antitumor immunity. Here, cascade cell membrane coating is reported to prepare biomimetic nanoparticles (BNs) that can manipulate the cross-priming of T cells. BNs are obtained from coating nanoparticulate substrates with cell membranes extracted from dendritic cells (DCs) that are pre-pulsed with cancer cell membrane-coated nanoparticles. With a DC membrane that presents an array of cancer cell membrane antigen epitopes, BNs inherit the intrinsic membrane function of DCs, which can directly cross-prime T cells and provoke robust yet antigen-specific antitumor responses in multiple mouse models. Combination with clinical anti-programmed death-1 antibodies demonstrates a robust way of BNs to achieve desirable tumor regression and survival rate. This work spotlights the impact of nanoparticles on direct cross-priming of T cells and supports a unique yet modulate platform for boosting an effective adaptive immunity for immunotherapy.

Berberine-Loaded Biomimetic Nanoparticles Attenuate Inflammation of Experimental Allergic Asthma via Enhancing IL-12 Expression

Asthma is one of the most common chronic pulmonary disorders, affecting more than 330 million people worldwide. Unfortunately, there are still no specific treatments for asthma so far. Therefore, it is very important to develop effective therapeutics and medicines to deal with this intractable disease. Berberine (Ber) has fabulous anti-inflammatory and antibacterial effects, while its low water solubility and bioavailability greatly limit its curative efficiency. To improve the nasal mucosa absorption of poorly water-soluble drugs, such as Ber, we developed a platelet membrane- (PM-) coated nanoparticle (NP) system (PM@Ber-NPs) for targeted delivery of berberine to the inflammatory lungs. In vivo, PM@Ber-NPs exhibited enhanced targeting retention in the inflammatory lungs compared with free Ber. In a mouse model of house dust mite- (HDM-) induced asthma, PM@Ber-NPs markedly inhibited lung inflammation, as evident by reduced inflammatory cells and inflammatory cytokines in the lung compared with free Ber. Collectively, our study demonstrated the inhibitory actions of nasally delivered nanomedicines on HDM-induced asthma, primarily through regulating Th1/Th2 balance by enhancing IL-12 expression which could potentially reduce lung inflammation and allergic asthma.

Biomimetic Nanoparticles Coated with Bacterial Outer Membrane Vesicles as a New-Generation Platform for Biomedical Applications

The biomedical field is currently reaping the benefits of research on biomimetic nanoparticles (NPs), which are synthetic nanoparticles fabricated with natural cellular materials for nature-inspired biomedical applications. These camouflage NPs are capable of retaining not only the physiochemical properties of synthetic nanoparticles but also the original biological functions of the cellular materials. Accordingly, NPs coated with cell-derived membrane components have achieved remarkable growth as prospective biomedical materials. Particularly, bacterial outer membrane vesicle (OMV), which is a cell membrane coating material for NPs, is regarded as an important molecule that can be employed in several biomedical applications, including immune response activation, cancer therapeutics, and treatment for bacterial infections with photothermal activity. The currently available cell membrane-coated NPs are summarized in this review. Furthermore, the general features of bacterial OMVs and several multifunctional NPs that could serve as inner core materials in the coating strategy are presented, and several methods that can be used to prepare OMV-coated NPs (OMV-NPs) and their characterization are highlighted. Finally, some perspectives of OMV-NPs in various biomedical applications for future potential breakthrough are discussed. This in-depth review, which includes potential challenges, will encourage researchers to fabricate innovative and improvised, new-generation biomimetic materials through future biomedical applications.

Macrophage-Disguised Manganese Dioxide Nanoparticles for Neuroprotection by Reducing Oxidative Stress and Modulating Inflammatory Microenvironment in Acute Ischemic Stroke

Reperfusion injury is still a major challenge that impedes neuronal survival in ischemic stroke. However, the current clinical treatments are remained on single pathological process, which are due to lack of comprehensive neuroprotective effects. Herein, a macrophage-disguised honeycomb manganese dioxide (MnO2 ) nanosphere loaded with fingolimod (FTY) is developed to salvage the ischemic penumbra. In particular, the biomimetic nanoparticles can accumulate actively in the damaged brain via macrophage-membrane protein-mediated recognition with cell adhesion molecules that are overexpressed on the damaged vascular endothelium. MnO2 nanosphere can consume excess hydrogen peroxide (H2 O2 ) and convert it into desiderated oxygen (O2 ), and can be decomposed in acidic lysosome for cargo release, so as to reduce oxidative stress and promote the transition of M1 microglia to M2 type, eventually reversing the proinflammatory microenvironment and reinforcing the survival of damaged neuron. This biomimetic nanomedicine raises new strategy for multitargeted combined treatment of ischemic stroke.

Biomimetic Nanoparticles Carrying a Repolarization Agent of Tumor-Associated Macrophages for Remodeling of the Inflammatory Microenvironment Following Photothermal Therapy

The complete regression of residual tumors after photothermal therapy (PTT) depends on the activation and recognition of the immune system. However, the inevitable local inflammation after PTT in residual tumor recruits abundant abnormal immune cells, especially the tumor-associated macrophages (TAMs) which further promote immune escape and survival of the remaining tumor cells, resulting in the tumor recurrence and progression. To solve this problem, herein we explored biomimetic nanoparticles carrying repolarization agent of TAMs to remodel the post-PTT inflammatory microenvironment. The polydopamine nanoparticles were used simultaneously as photothermal transduction agents to ablate tumor cells and the delivery vehicles for TMP195 which can repolarize the M2-like TAMs into an antitumor phenotype. In addition, a biomimetic decoration of macrophage membrane coating was designed to endow nanoparticles the ability to actively target the tumor site after PTT mediated by inflammation-mediated chemotaxis. In the breast tumor model, these biomimetic nanoparticles with immune-modulating ability significantly elevated the levels of M1-like TAMs, ultimately resulting in a tumor-elimination rate of 60%, increased from 10% after PTT. This synergistic treatment strategy of PTT and TAMs repolarization provides a promising approach to address the deteriorated tumor microenvironment after PTT and proposes a more effective way for combinational treatment option in clinic.

Biomimetic Black Phosphorus Nanosheet-Based Drug Delivery System for Targeted Photothermal-Chemo Cancer Therapy

As a biodegradable material, black phosphorus (BP) has been considered as an efficient agent for cancer photothermal therapy. However, its systemic delivery faces several hurdles, including rapid degradation in blood circulation, quick clearance by the immune system, and low delivery sufficiency to the tumor site. Here, we developed a biomimetic nanoparticle platform for in vivo tumor-targeted delivery of BP nanosheets (BP NSs). Through a biomimetic strategy, BP NSs were utilized to coordinate with the active species of oxaliplatin (1,2-diaminocyclohexane) platinum (II) (DACHPt) complexions, and the nanoparticles were further camouflaged with mesenchymal stem cell (MSC)–derived membranes. We showed that the incorporation of DACHPt not only decelerated the BP degradation but also enhanced the antitumor effect by combining the photothermal effect with chemotoxicity. Furthermore, MSC membrane coating increased the stability, dispersibility, and tumor-targeting properties of BP/DACHPt, significantly improving the antitumor efficacy. In short, our work not only provided a new strategy for in vivo tumor-targeted delivery of BP NSs but also obtained an enhanced antitumor effect by combining photothermal therapy with chemotherapy.

Biomaterials, biological molecules, and polymers in developing vaccines

Vaccines have been used to train the immune system to recognize pathogens, and prevent and treat diseases, such as cancer, for decades. However, there are continuing challenges in their manufacturing, large-scale production, and storage. Some of them also show suboptimal immunogenicity, requiring additional adjuvants and booster doses. As an alternate vaccination strategy, a new class of biomimetic materials with unique functionalities has emerged in recent years. Here, we explore the current bioengineering techniques that make use of hydrogels, modified polymers, cell membranes, self-assembled proteins, virus-like particles (VLPs), and nucleic acids to deliver and develop biomaterial-based vaccines. We also review design principles and key regulatory issues associated with their development. Finally, we critically assess their limitations, explore approaches to overcome these limitations, and discuss potential future applications for clinical translation.

Erythrocyte-cancer hybrid membrane-camouflaged mesoporous silica nanoparticles loaded with Gboxin for glioma-targeting therapy

OBJECTIVE

The purpose of this research is to formulate a biomimetic drug delivery system that can selectively target glioblastoma (GBM) to deliver the antitumor agent, Gboxin: a novel Complex V inhibitor. Gboxin can specifically inhibit GBM cell growth but not normal cells.

METHODS

In the present study, we utilized Red Blood Cell (RBC) membrane and U251 cell membrane to obtain a hybrid biomimetic membrane (RBC-U), and prepared RBC-U coated Gboxin-loaded mesoporous silica nanoparticles ((MSNs/Gboxin)@[RBC-U]) for GBM chemotherapy. The zeta potential, particle size, and morphology of (MSNs/Gboxin)@[RBC-U] were characterized. The cellular uptake, effect of cells growth inhibition, biocompatibility, and specific self-recognition of nanoparticles were evaluated.

RESULTS

The (MSNs/Gboxin)@[RBC-U] was successfully fabricated and possessed high stability in the circulation system. The drug loading of Gboxin was 13.9%. (MSNs/Gboxin)@[RBC-U], effectively retain drugs in the physiological environment and releasing Gboxin rapidly in the tumor cells. Compared to the MSNs/Gboxin, the (MSNs/Gboxin)@[RBC-U] exhibited highly specific self-recognition to the source cell line. Additionally, the (MSNs/Gboxin)@[RBC-U] showed excellent anti-proliferation efficiency (IC₅₀ = 0.21 μg/mL) in the tumor cell model and a few side effects in normal cells in vitro.

CONCLUSION

The (MSNs/Gboxin)@[RBC-U] exhibited significant anti-cancer effects in vitro and the specific self-recognition to GBM cells. Hence, (MSNs/Gboxin)@[RBC-U] could be a promising delivery system for GBM targeted therapy.

ROS-responsive biomimetic nanoparticles for potential application in targeted anti-atherosclerosis

The development of nanomedicines provides new opportunities for the treatment of atherosclerosis (AS) due to their great advantages such as the improved drug solubility, enhanced bioavailability and reduced side effects. Despite these advantages, nanomedicines are still facing some challenges. The problems remain in the short circulation life, lack of specific targeting and poor drug release controllability. In order to overcome the shortages of conventional nanomedicines, the combination of biomimetic strategy with smart nanoagents has been proposed. In light with the high reactive oxygen species (ROS) level in AS microenvironment and the fact that macrophages play a critical role in the pathogenesis of AS, we fabricated ROS-responsive biomimetic nanoparticles (NPs), which camouflaged macrophage membrane (MM) on ROS-responsive NPs loaded with rapamycin (RNPs) for potential application in AS therapy. The resulting ROS-responsive biomimetic NPs (MM/RNPs) exhibited favorable hydrodynamic size with negative surface charge, retained the functional proteins from MM, and showed ROS-responsive drug release. Because of the biomimetic camouflaging on surface, MM/RNPs could effectively escape from macrophages uptake and target to inflammatory endothelial cells. Meanwhile, MM/RNPs could inhibit the proliferation of macrophages and smooth muscle cells in vitro. Furthermore, the MM-coated NPs were found to be nontoxic in both cytotoxicity assay and in vivo toxicity evaluation. Consequently, these results demonstrated that MM/RNPs could be a potential candidate of drug delivery system for safe and effective anti-AS applications.

Antiviral and Anti‐Inflammatory Treatment with Multifunctional Alveolar Macrophage‐Like Nanoparticles in a Surrogate Mouse Model of COVID‐19

The pandemic of coronavirus disease 2019 (COVID‐19) is continually worsening. Clinical treatment for COVID‐19 remains primarily supportive with no specific medicines or regimens. Here, the development of multifunctional alveolar macrophage (AM)‐like nanoparticles (NPs) with photothermal inactivation capability for COVID‐19 treatment is reported. The NPs, made by wrapping polymeric cores with AM membranes, display the same surface receptors as AMs, including the coronavirus receptor and multiple cytokine receptors. By acting as AM decoys, the NPs block coronavirus from host cell entry and absorb various proinflammatory cytokines, thus achieving combined antiviral and anti‐inflammatory treatment. To enhance the antiviral efficiency, an efficient photothermal material based on aggregation‐induced emission luminogens is doped into the NPs for virus photothermal disruption under near‐infrared (NIR) irradiation. In a surrogate mouse model of COVID‐19 caused by murine coronavirus, treatment with multifunctional AM‐like NPs with NIR irradiation decreases virus burden and cytokine levels, reduces lung damage and inflammation, and confers a significant survival advantage to the infected mice. Crucially, this therapeutic strategy may be clinically applied for the treatment of COVID‐19 at early stage through atomization inhalation of the NPs followed by NIR irradiation of the respiratory tract, thus alleviating infection progression and reducing transmission risk.