PEGylated nanoparticles interact with macrophages independently of immune response factors and trigger a non-phagocytic, low-inflammatory response

PEGylation technology: addressing concerns, moving forward

PEGylation technology, that is grafting of poly(ethylene glycol)(PEG) to biologics, vaccines and nanopharmaceuticals, has become a cornerstone of modern medicines with over thirty products used in the clinic. PEGylation of therapeutic proteins, nucleic acids and nanopharmaceuticals improves their stability, pharmacokinetic and biodistribution. While PEGylated medicines are safe in the majority of patients, there are growing concerns about the emergence of anti-PEG antibodies and their impact on the therapeutic efficacy of PEGylated medicines as well as broader immune responses, particularly in complement activation and hypersensitivity reactions. These concerns are beginning to scrutinize the future viability of PEGylation technology in medicine design. Here, we outline these concerns, encourage more efforts into looking for comprehensive scientific evidence on the role of anti-PEG antibodies in hypersensitivity reactions, discuss alternatives to PEG and propose strategies for moving PEGylation technology forward.

Recent advances in nanocrystals for arthritis drug delivery

INTRODUCTION

More than 500 million people worldwide suffer from arthritis, experiencing daily pain and inflammation. Current treatments for osteoarthritis (OA) and rheumatoid arthritis (RA) are palliative, offering only symptom relief. No disease-modifying OA drugs (DMOADs) capable of restoring joint functionality and regenerating the cartilage matrix have yet been approved by the FDA or EMA.

AREAS COVERED

This review highlights recent advances in nanocrystals (NCs) for arthritis drug delivery, including conventional nanosuspensions and novel transdermal microneedles. Special attention is given to intra-articular DMOADs formulated as NC-in-microparticles, designed to extend drug release over months. Papers and reviews with the mentioned contents and published over the last 5 years were included in the review process.

EXPERT OPINION

New DMOADs and disease-modifying antirheumatic drugs (DMARDs) are often poorly water-soluble, limiting their clinical progress. The versatility of NCs and nanosuspensions offers a potential advantage over other types of nanoparticles, as they can be adapted to various delivery systems, administration routes, and types of arthritis. Due to the avascular nature of cartilage, exploring the intra-articular route for OA management is essential. Implementing cartilage-targeted strategies or using stimuli-responsive hydrogels can further enhance their therapeutic potential.

Nanotechnology Assisted Drug Delivery Strategies for Chemotherapy: Recent Advances and Future Prospects

In pursuit of the treatment of cancer, nanotechnology engineering has emerged as the simplest and most effective means, with the potential to deliver antitumor chemotherapeutics at the targeted site. Employing nanotechnology for drug delivery provides diverse nanosize particles ranging from one to a thousand nanometers. Reduced size improves drug bioavailability by increasing drug diffusion and decreasing the efflux rate. These nanocarriers offer an enormous scope for modification following the chemical and biological properties of both the drug and its disease. Moreover, these nanoformulations assist in targeting pharmaceutically active drug molecules to the desired site and have gained importance in recent years. Their modern use has revolutionized the antitumor action of many therapeutic agents. Higher drug loading efficiency, thermal stability, easy fabrication, low production cost, and large-scale industrial production draw attention to the application of nanotechnology as a better platform for the delivery of drug molecules. Furthermore, the interaction of nanocarrier technology-assisted agents lowers a drug's toxicity and therapeutic dosage, reduces drug tolerance, and enhances active drug concentration in neoplasm tissue, thus decreasing the concentration in healthy tissue. Nanotechnology-based medications are being widely explored and have depicted effective cancer management in vivo and in vitro systems, leading to many clinical trials with promising results. This review summarizes the innovative impact and application of different nanocarriers developed in recent years in cancer therapy. Subsequently, it also describes the essential findings and methodologies and their effects on cancer treatment. Compared with conventional therapy, nanomedicines can significantly improve the therapeutic effectiveness of antitumor drugs. Thus, the adverse effects associated with healthy tissues are decreased, and adverse effects are scaled back through enhanced permeability and retention effects. Lastly, future insights assisting nanotechnology in active therapeutics delivery and their scope in cancer chemotherapeutics have also been discussed.

Design and Biodistribution of PEGylated Core-Shell X-ray Fluorescent Nanoparticle Contrast Agents

Nanoparticle (NP) uptake by macrophages and their accumulation in undesired organs such as the liver and spleen constitute a major barrier to the effective delivery of NPs to targeted tissues for bioimaging and therapeutics. Surface functionalization with polyethylene glycol (PEG) has been demonstrated to be a promising strategy to limit NP sequestration, although its longitudinal stability under physiological conditions and impact on the NP biodistribution have not been investigated with an in vivo quantitative approach. X-ray fluorescence (XRF) imaging has been employed to noninvasively map the in vivo biodistribution of purposely designed molybdenum-based contrast agents, leading to submillimeter resolution, elemental specificity, and high penetration depth. In the present work, we design a stepwise layering approach for NP synthesis to investigate the role of chemisorbed and physisorbed PEG on silica-coated molybdenum-based contrast agents in affecting their in vivo biodistribution, using whole-body XRF imaging. Comparative quantitative in vivo studies indicated that physisorbed PEG (1.5 kDa) did not substantially affect the biodistribution, while the chemisorption route with mPEG-Si (6-9 PEG units) led to significant macroscopic variations in the biodistribution, leading to a reduction in NP uptake by the liver. Furthermore, the results highlighted the major role of the spleen in compensating for the limited sequestration by the liver, microscopically validated with a multiscale imaging approach with fluorophore doping of the silica shell. These findings demonstrated the promising role of XRF imaging for the rapid assessment of surface-functionalized contrast agents with whole-body in vivo quantitative pharmacokinetic studies, establishing the groundwork for developing strategies to identify and bypass undesired NP uptake.

Inhalable Nano Formulation of Cabazitaxel: A Comparative Study with Intravenous Route

Chemotherapy is generally given by intravenous (IV) administration which provides higher bioavailability than other systemic routes. However, in the case of lung cancer, the pulmonary (INH) route is the other choice for inhalable formulations. In the study, biochemical and histological parameters of Cabazitaxel (CBZ) free (2 mg kg-1) and nanoparticle (NP) (2 mg kg-1 CBZ equivalent) formulations are investigated after IV and INH administration in rats. The nanoformulation of CBZ is obtained using PEGylated polystyrene (PEG-PST) nanoparticles obtained by PISA. While a nose and head-only device is used for INH administration, a jugular vein is used as the IV route. Blood samples (blank, 24 h, and 48 h) are collected via carotid artery cannulas without handling in metabolism cages. According to biochemical parameters, free CBZ formulation applied via IV or INH route shows higher systemic toxicity. On the other hand, the nanoformulation of CBZ showed no signs of toxicity in both IV or INH routes. Higher and longer retention is observed in the case of inhaled nanoformulation. Histological analysis showed higher alveolar macrophage migration for inhaled nanoformulation due to enhanced retention. Results showed that nanotechnology and the lung defense system gave the advantage to end up with an inhalable nanomedicine formulation for lung cancer.

Advancements in nanoparticle-based vaccine development against Japanese encephalitis virus: a systematic review

Vaccination remains the sole effective strategy for combating Japanese encephalitis (JE). Both inactivated and live attenuated vaccines exhibit robust immunogenicity. However, the production of these conventional vaccine modalities necessitates extensive cultivation of the pathogen, incurring substantial costs and presenting significant biosafety risks. Moreover, the administration of live pathogens poses potential hazards for individuals or animals with compromised immune systems or other health vulnerabilities. Subsequently, ongoing research endeavors are focused on the development of next-generation JE vaccines utilizing nanoparticle (NP) platforms. This systematic review seeks to aggregate the research findings pertaining to NP-based vaccine development against JE. A thorough literature search was conducted across established English-language databases for research articles on JE NP vaccine development published between 2000 and 2023. A total of twenty-eight published studies were selected for detailed analysis in this review. Of these, 16 studies (57.14%) concentrated on virus-like particles (VLPs) employing various structural proteins. Other approaches, including sub-viral particles (SVPs), biopolymers, and both synthetic and inorganic NP platforms, were utilized to a lesser extent. The results of these investigations indicated that, despite variations in the usage of adjuvants, dosages, NP types, antigenic proteins, and animal models employed across different studies, the candidate NP vaccines developed were capable of eliciting enhanced humoral and cellular adaptive immune responses, providing effective protection (70-100%) for immunized mice against lethal challenges posed by virulent Japanese encephalitis virus (JEV). In conclusion, prospective next-generation JE vaccines for humans and animals may emerge from these candidate formulations following further evaluation in subsequent vaccine development phases.

Polyethylene Glycols Stimulate Ca2+ Signaling, Cytokine Production, and the Formation of Neutrophil Extracellular Traps

Purpose

Given the increased use of polyethylene glycol (PEG) in refining the therapeutic activity of medicines, our research focuses on explaining the potential mechanism of immune reactions associated with this polymer. We aim to investigate the interaction of different types of PEG with mouse and human immune cells, thereby contributing to understanding PEG interactions with the immune system and verifying the proinflammatory activity of the tested polymers.

Patients and Methods

Mouse macrophage and neutrophil cell lines, human peripheral blood mononuclear cells, and polymorphonuclear cells isolated from healthy donors were exposed to various PEGs. ROS, NO, and cytokine production were analyzed using fluorescence intensity, absorbance, or cytometric measurements. Toll-like receptor (TLR) signaling was verified using HEK-blue-reporter cell lines. Finally, neutrophil trap formation was studied using immunofluorescence labeling, and calcium imaging was performed using a Ca2+-sensitive indicator and fluorescence microscope.

Results

Our findings show that specific PEG and mPEG are not toxic to tested mouse and human cells. However, they exert proinflammatory activity against human immune cells, as evidenced by the increased secretion of proinflammatory cytokines, such as IFN-a2, IFN-γ, TNF-α, MCP-1, IL-8, IL-17A, and IL-23. This phenomenon is independent of PEG signaling via TLR. Additionally, mPEG10 induced the formation of neutrophil extracellular traps and intracellular calcium signaling.

Conclusion

Our finding suggests that some PEG types have proinflammatory activity against human immune cells, manifesting in the upregulated production of cytokines and neutrophils trap releasing.

Age-dependent changes in phagocytic activity: in vivo response of mouse pulmonary antigen presenting cells to direct lung delivery of charged PEGDA nanoparticles

BACKGROUND

Current needle-based vaccination for respiratory viruses is ineffective at producing sufficient, long-lasting local immunity in the elderly. Direct pulmonary delivery to the resident local pulmonary immune cells can create long-term mucosal responses. However, criteria for drug vehicle design rules that can overcome age-specific changes in immune cell functions have yet to be established.

RESULTS

Here, in vivo charge-based nanoparticle (NP) uptake was compared in mice of two age groups (2- and 16-months) within the four notable pulmonary antigen presenting cell (APC) populations: alveolar macrophages (AM), interstitial macrophages (IM), CD103+ dendritic cells (DCs), and CD11b+ DCs. Both macrophage populations exhibited preferential uptake of anionic nanoparticles but showed inverse rates of phagocytosis between the AM and IM populations across age. DC populations demonstrated preferential uptake of cationic nanoparticles, which remarkably did not significantly change in the aged group. Further characterization of cell phenotypes post-NP internalization demonstrated unique surface marker expression and activation levels for each APC population, showcasing heightened DC inflammatory response to NP delivery in the aged group.

CONCLUSION

The age of mice demonstrated significant preferences in the charge-based NP uptake in APCs that differed greatly between macrophages and DCs. Carefully balance of the targeting and activation of specific types of pulmonary APCs will be critical to produce efficient, age-based vaccines for the growing elderly population.

Entry of nanoparticles into cells and tissues: status and challenges

In this article we discuss how nanoparticles (NPs) of different compositions may interact with and be internalized by cells, and the consequences of that for cellular functions. A large number of NPs are made with the intention to improve cancer treatment, the goal being to increase the fraction of injected drug delivered to the tumor and thereby improve the therapeutic effect and decrease side effects. Thus, we discuss how NPs are delivered to tumors and some challenges related to investigations of biodistribution, pharmacokinetics, and excretion. Finally, we discuss requirements for bringing NPs into clinical use and aspects when it comes to usage of complex and slowly degraded or nondegradable NPs.

Understanding nanoparticle-liver interactions in nanomedicine

INTRODUCTION

Understanding the interactions between administered nanoparticles and the liver is crucial for developing safe and effective nanomedicines. As the liver can sequester up to 99% of these particles due to its major phagocytic role, understanding these interactions is vital for clinical translation.

AREAS COVERED

This review highlights recent studies on nanoparticle-liver interactions, including the influence of nanoparticle physicochemical properties on delivery, strategies to enhance delivery efficiency by modulating liver Kupffer cells, and their potential for treating certain hepatic diseases. Additionally, we discuss how aging impacts the liver's phagocytic functions.

EXPERT OPINION

While liver accumulation can hinder nanomedicine safety and effectiveness, it also presents opportunities for treating certain liver diseases. A thorough understanding of nanoparticle-liver interactions is essential for advancing the clinical application of nanomedicines.