Enhanced Liposomal Drug Delivery Via Membrane Fusion Triggered by Dimeric Coiled-Coil Peptides

Combating cisplatin-resistant lung cancer using a coiled-coil lipopeptides modified membrane fused drug delivery system

Drug resistance to chemotherapy in treating cancers becomes an increasingly serious challenge, which leads to treatment failure and poor patient survival. Drug-resistant cancer cells normally reduce intracellular accumulation of drugs by controlling drug uptake and promoting drug efflux, which severely limits the efficacy of chemotherapy. To overcome this problem, a membrane fused drug delivery system (MF-DDS) was constructed to treat cisplatin (DDP)-resistant lung cancer (A549-DDP) by delivering DDP via membrane fusion using a complementary coiled-coil forming peptides (CP8K4/CP8E4). The lipopeptide CP8K4 was pre-incubated firstly and decorated on the surface of A549-DDP cells, and then the cells interacted with the lipopeptide CP8E4 modified on the lipid bilayer (LB) coated PLGA nanoparticles loading DDP (PLGA-DDP@LB-CP8E4), leaded to the direct cytosolic DDP delivery and cancer cell death. Compared with free DDP, this MF-DDS achieved a 13.42-folds reduced IC50 value of A549-DDP cells in vitro, and tumor size was down-regulated, showing only 1/5.26 of the original weight in vivo. Meanwhile, the anti-drug resistant mechanism was explored, where the MF-DDS inhibited the expression of efflux protein genes, including MRP1, MRP2, and ABCG2, leading to increased intracellular drug accumulations. Altogether, this MF-DDS effectively delivered DDP into DDP-resistant cancer cells, making it a promising and improved pharmacological therapeutic approach for drug-resistant tumor treatment.

Liposomal-Based Nanoarchitectonics as Bispecific T Cell Engagers in Neuroblastoma Therapy

Neuroblastoma (NB) is an aggressive pediatric solid tumor that lacks efficient treatment. In the past few years, the use of engineered lymphocytes endowed with chimeric antigen receptors (CAR T), which improve their natural search and destroy skills against tumoral cells, has provided a highly valuable strategy to eradicate tumors in a specific and safe manner. Unfortunately, despite the excellent results achieved by these cell-based therapies in liquid tumors, their efficacy in the treatment of solid malignancies is usually modest due to the existence of several biological barriers which compromise their efficacy. Herein, a strategy to guide CAR T toward NB cells based on the use of nanometric bispecific T engagers (NBTEs) is presented. These novel bispecific nanoplatforms are based on liposomes and protocells doubly functionalized with synthetic targeting moieties (para-aminobenzylguanidine and fluorescein) able to selectively bind to membrane cell receptors of NB and anti-FITC CAR T, respectively. The binding process of NBTEs to NB cells was monitored by confocal fluorescence microscopy showing the excellent capacity of these nanodevices to place fluorescence labels on the surface of the malignant cells. Then, NB cells previously incubated in the presence of NBTEs were rapidly detected and destroyed by anti-FITC CAR T, which confirmed the excellent capacity of these nanoplatforms to improve the natural capacity of CAR T to eradicate malignant cells. Finally, the high versatility of the NBTE design and its easy-to-tune nature would allow their rapid application to different types of solid tumors.

Microfluidic Chip for Cell Fusion and In Situ Separation of Fused Cells

Electrofusion is an effective method for fusing two cells into a hybrid cell, and this method is widely used in immunomedicine, gene recombination, and other related fields. Although cell pairing and electrofusion techniques have been accomplished with microfluidic devices, the purification and isolation of fused cells remains limited due to expensive instruments and complex operations. In this study, through the optimization of microstructures and electrodes combined with buffer substitution, the entire cell electrofusion process, including cell capture, pairing, electrofusion, and precise separation of the targeted fused cells, is achieved on a single chip. The proposed microfluidic cell electrofusion achieves an efficiency of 80.2 ± 7.5%, and targeted cell separation could be conveniently performed through the strategic activation of individual microelectrodes via negative dielectrophoresis, which ensures accurate release of the fused cells with an efficiency of up to 91.1 ± 5.1%. Furthermore, the survival rates of the cells after electrofusion and release are as high as 94.7 ± 0.6% and 91.7 ± 1.2%, respectively. These results demonstrate that the in situ cell electrofusion and separation process did not affect the cell activity. This chip offers integrated multifunctional manipulation of cells in situ, and can be applied to multiple fields in the future, thus laying the foundation for the field of precise single-cell analysis.

Developing Cell-Membrane-Associated Liposomes for Liver Diseases

Over the past decade, a marked escalation in the prevalence of hepatic pathologies has been observed, adversely impacting the quality of life for many. The predominant therapeutic strategy for liver diseases has been pharmacological intervention; however, its efficacy is often constrained. Currently, liposomes are tiny structures that can deliver drugs directly to targeted areas, enhancing their effectiveness. Specifically, cell membrane-associated liposomes have gained significant attention. Despite this, there is still much to learn about the binding mechanism of this type of liposome. Thus, this review comprehensively summarizes relevant information on cell membrane-associated liposomes, including their clinical applications and future development directions. First, we will briefly introduce the composition and types of cell membrane-associated liposomes. We will provide an overview of their structure and discuss the various types of liposomes associated with cell membranes. Second, we will thoroughly discuss various strategies of drug delivery using these liposomes. Lastly, we will discuss the application and clinical challenges associated with using cell membrane-associated liposomes in treating liver diseases. We will explore their potential benefits while also addressing the obstacles that need to be overcome. Furthermore, we will provide prospects for future development in this field. In summary, this review underscores the promise of cell membrane-associated liposomes in enhancing liver disease treatment and highlights the need for further research to optimize their utilization. In summary, this review underscores the promise of cell membrane-associated liposomes in enhancing liver disease treatment and highlights the need for further research to optimize their utilization.

The art of designed coiled-coils for the regulation of mammalian cells

Synthetic biology aims to engineer complex biological systems using modular elements, with coiled-coil (CC) dimer-forming modules are emerging as highly useful building blocks in the regulation of protein assemblies and biological processes. Those small modules facilitate highly specific and orthogonal protein-protein interactions, offering versatility for the regulation of diverse biological functions. Additionally, their design rules enable precise control and tunability over these interactions, which are crucial for specific applications. Recent advancements showcase their potential for use in innovative therapeutic interventions and biomedical applications. In this review, we discuss the potential of CCs, exploring their diverse applications in mammalian cells, such as synthetic biological circuit design, transcriptional and allosteric regulation, cellular assemblies, chimeric antigen receptor (CAR) T cell regulation, and genome editing and their role in advancing the understanding and regulation of cellular processes.

Deconvolving Passive and Active Targeting of Liposomes Bearing LDL Receptor Binding Peptides Using the Zebrafish Embryo Model

Improving target versus off-target ratio in nanomedicine remains a major challenge for increasing drug bioavailability and reducing toxicity. Active targeting using ligands on nanoparticle surfaces is a key approach but has limited clinical success. A potential issue is the integration of targeting ligands also changes the physicochemical properties of nanoparticles (passive targeting). Direct studies to understand the mechanisms of active targeting and off-targeting in vivo are limited by the lack of suitable tools. Here, the biodistribution of a representative active targeting liposome is analyzed, modified with an apolipoprotein E (ApoE) peptide that binds to the low-density lipoprotein receptor (LDLR), using zebrafish embryos. The ApoE liposomes demonstrated the expected liver targeting effect but also accumulated in the kidney glomerulus. The ldlra-/- zebrafish is developed to explore the LDLR-specificity of ApoE liposomes. Interestingly, liver targeting depends on the LDLR-specific interaction, while glomerular accumulation is independent of LDLR and peptide sequence. It is found that cationic charges of peptides and the size of liposomes govern glomerular targeting. Increasing the size of ApoE liposomes can avoid this off-targeting. Taken together, the study shows the potential of the zebrafish embryo model for understanding active and passive targeting mechanisms, that can be used to optimize the design of nanoparticles.

Lipid-Based Nanoparticle Functionalization with Coiled-Coil Peptides for In Vitro and In Vivo Drug Delivery

For the delivery of drugs, different nanosized drug carriers (e.g., liposomes, lipid nanoparticles, and micelles) have been developed in order to treat diseases that afflict society. Frequently, these vehicles are formed by the self-assembly of small molecules to encapsulate the therapeutic cargo of interest. Over decades, nanoparticles have been optimized to make them more efficient and specific to fulfill tailor-made tasks, such as specific cell targeting or enhanced cellular uptake. In recent years, lipid-based nanoparticles in particular have taken center stage; however, off-targeting side effects and poor endosomal escape remain major challenges since therapies require high efficacy and acceptable toxicity.To overcome these issues, many different approaches have been explored to make drug delivery more specific, resulting in reduced side effects, to achieve an optimal therapeutic effect and a lower required dose. The fate of nanoparticles is largely dependent on size, shape, and surface charge. A common approach to designing drug carriers with targeting capability is surface modification. Different approaches to functionalize nanoparticles have been investigated since the attachment of targeting moieties plays a significant role in whether they can later interact with surface-exposed receptors of cells. To this end, various strategies have been used involving different classes of biomolecules, such as small molecules, nucleic acids, antibodies, aptamers, and peptides.Peptides in particular are often used since there are many receptors overexpressed in different specific cell types. Furthermore, peptides can be produced and modified at a low cost, enabling high therapeutic screening. Cell-penetrating peptides (CPPs) and cell-targeting peptides (CTPs) are frequently used for this purpose. Less studied in this context are fusogenic coiled-coil peptides. Lipid-based nanoparticles functionalized with these peptides are able to avoid the endolysosomal pathway; instead such particles can be taken up by membrane fusion, resulting in increased delivery of payload. Furthermore, they can be used for targeting cells/organs but are not directed at surface-exposed receptors. Instead, they recognize complementary peptide sequences, facilitating their uptake into cells.In this Account, we will discuss peptides as moieties for enhanced cytosolic delivery, targeted uptake, and how they can be attached to lipid-based nanoparticles to alter their properties. We will discuss the properties imparted to the particles by peptides, surface modification approaches, and recent examples showing the power of peptides for in vitro and in vivo drug delivery. The main focus will be on the functionalization of lipid-based nanoparticles by fusogenic coiled-coil peptides, highlighting the relevance of this concept for the development of future therapeutics.

Rigid-flexible nanocarriers loaded with active peptides for antioxidant and anti-inflammatory applications in skin

Peptides are recognized as highly effective and safe bioactive ingredients. However, t their practical application is limited and hampered by harsh conditions for practical drug delivery. Hence, a novel peptide nanocarrier of copper peptide (GHK-Cu) encapsulation developed by liposome technology combined with the classical Chinese concept of rigidity and flexibility. Different polyols were selected as modification ligands for phospholipid bilayers to construct a nano drug-carrying system with high loading rate, good stability and biocompatibility. In vitro, this complex not only significantly retarded the release ability of copper peptides, but also enabled copper peptides to be effectively resistant to enzymatic degradation. Furthermore, cellular experiments showed that this system mainly regulates Nrf2, SIRT1, and PEG2/COX-2-related signaling pathways, thus effectively counteracting cellular inflammation, senescence, and apoptosis from oxidative damage. Interestingly, a green, non-toxic, efficient and convenient antioxidant system was developed for the prevention and deceleration of skin aging.

Vortex fluidic regulated phospholipid equilibria involving liposomes down to sub-micelle size assemblies

Conventional channel-based microfluidic platforms have gained prominence in controlling the bottom-up formation of phospholipid based nanostructures including liposomes. However, there are challenges in the production of liposomes from rapidly scalable processes. These have been overcome using a vortex fluidic device (VFD), which is a thin film microfluidic platform rather than channel-based, affording ∼110 nm diameter liposomes. The high yielding and high throughput continuous flow process has a 45° tilted rapidly rotating glass tube with an inner hydrophobic surface. Processing is also possible in the confined mode of operation which is effective for labelling pre-VFD-prepared liposomes with fluorophore tags for subsequent mechanistic studies on the fate of liposomes under shear stress in the VFD. In situ small-angle neutron scattering (SANS) established the co-existence of liposomes ∼110 nm with small rafts, micelles, distorted micelles, or sub-micelle size assemblies of phospholipid, for increasing rotation speeds. The equilibria between these smaller entities and ∼110 nm liposomes for a specific rotational speed of the tube is consistent with the spatial arrangement and dimensionality of topological fluid flow regimes in the VFD. The prevalence for the formation of ∼110 nm diameter liposomes establishes that this is typically the most stable structure from the bottom-up self-assembly of the phospholipid and is in accord with dimensions of exosomes.

Fusogenic Coiled-Coil Peptides Enhance Lipid Nanoparticle-Mediated mRNA Delivery upon Intramyocardial Administration

Heart failure is a serious condition that results from the extensive loss of specialized cardiac muscle cells called cardiomyocytes (CMs), typically caused by myocardial infarction (MI). Messenger RNA (mRNA) therapeutics are emerging as a very promising gene medicine for regenerative cardiac therapy. To date, lipid nanoparticles (LNPs) represent the most clinically advanced mRNA delivery platform. Yet, their delivery efficiency has been limited by their endosomal entrapment after endocytosis. Previously, we demonstrated that a pair of complementary coiled-coil peptides (CPE4/CPK4) triggered efficient fusion between liposomes and cells, bypassing endosomal entrapment and resulting in efficient drug delivery. Here, we modified mRNA-LNPs with the fusogenic coiled-coil peptides and demonstrated efficient mRNA delivery to difficult-to-transfect induced pluripotent stem-cell-derived cardiomyocytes (iPSC-CMs). As proof of in vivo applicability of these fusogenic LNPs, local administration via intramyocardial injection led to significantly enhanced mRNA delivery and concomitant protein expression. This represents the successful application of the fusogenic coiled-coil peptides to improve mRNA-LNPs transfection in the heart and provides the potential for the advanced development of effective regenerative therapies for heart failure.

Efficient mRNA delivery using lipid nanoparticles modified with fusogenic coiled-coil peptides

Gene delivery has great potential in modulating protein expression in specific cells to treat diseases. Such therapeutic gene delivery demands sufficient cellular internalization and endosomal escape. Of various nonviral nucleic acid delivery systems, lipid nanoparticles (LNPs) are the most advanced, but still, are very inefficient as the majority are unable to escape from endosomes/lysosomes. Here, we develop a highly efficient gene delivery system using fusogenic coiled-coil peptides. We modified LNPs, carrying EGFP-mRNA, and cells with complementary coiled-coil lipopeptides. Coiled-coil formation between these lipopeptides induced fast nucleic acid uptake and enhanced GFP expression. The cellular uptake of coiled-coil modified LNPs is likely driven by membrane fusion thereby omitting typical endocytosis pathways. This direct cytosolic delivery circumvents the problems commonly observed with the limited endosomal escape of mRNA. Therefore fusogenic coiled-coil peptide modification of existing LNP formulations to enhance nucleic acid delivery efficiency could be beneficial for several gene therapy applications.