Therapeutic synthetic and natural materials for immunoengineering

Nanodiamonds Interact with Primary Human Macrophages and Dendritic Cells Evoking a Vigorous Interferon Response

Nanodiamonds (NDs) display several attractive features rendering them useful for medical applications such as drug delivery. However, the interactions between NDs and the immune system remain poorly understood. Here, we investigated amino-, carboxyl-, and poly(ethylene glycol) (PEG)-terminated NDs with respect to primary human immune cells. We applied cytometry by time-of-flight (CyToF) to assess the impact on peripheral blood mononuclear cells at the single-cell level, and observed an expansion of plasmacytoid dendritic cells (pDCs) which are critically involved in antiviral responses. Subsequent experiments demonstrated that the NDs were actively internalized, leading to a vigorous type I interferon response involving endosomal Toll-like receptors. ND-NH2 and ND-COOH were more potent than ND-PEG, as evidenced by using TLR reporter cell lines. Computational studies demonstrated that NDs interacted with the ligand-binding domains of TLR7 and TLR9 with high affinity though this was less pronounced for ND-PEG. NDs with varying surface functionalities were also readily taken up by macrophages. To gain further insight, we performed RNA sequencing of a monocyte-like cell line exposed to NDs, and found that the phagosome maturation pathway was significantly affected. Indeed, evidence for lysosomal hyperacidification was obtained in dendritic cells and macrophages exposed to NDs. Moreover, using a reporter cell line, NDs were found to impinge on autophagic flux. However, NDs did not affect viability of any of the cell types studied. This study has shown that NDs subvert dendritic cells leading to an antiviral-like immune response. This has implications not only for drug delivery but also for anticancer vaccines using NDs.

Engineering an in vivo charging station for CAR-redirected invariant natural killer T cells to enhance cancer therapy

Invariant natural killer T (iNKT) cells are a distinct subset of T lymphocytes that possess unique properties making them highly suitable for addressing the challenges of solid tumor immunotherapy. Unlike conventional T cells, which are restricted by polymorphic major histocompatibility complex (MHC) molecules and recognize peptide antigens, iNKT cells are restricted by the non-polymorphic CD1d molecule and respond to lipid antigens. Chimeric antigen receptor (CAR)-redirected iNKT (CAR-iNKT) cells represent a significant advancement in cancer immunotherapy. However, optimizing sustained activation and long-term persistence of CAR-iNKT cells remains a critical need for effective solid tumor treatment. To address these limitations, we develop the iNKT cell-targeted microparticle recruitment and activation system (iMRAS), a biomimetic platform designed to enhance iNKT cell functionality through localized immunostimulation in vivo. This biomimetic platform is designed to function as an in vivo "charging station" containing chemotactic and activation signals for the recruitment, activation, and expansion of CAR-iNKT cells, leading to more effective tumor killing and longer persistence of CAR-iNKT cells, as demonstrated in the therapy of lymphoma and melanoma. Through its biomimetic design and localized immunostimulatory effects, iMRAS helps overcome the limitations of current therapies for solid tumors, establishing a robust platform for enhancing systemic CAR-iNKT cell-mediated immunotherapy.

Peptide hydrogel platform encapsulating manganese ions and high-density lipoprotein nanoparticle-mimicking nanovaccines for the prevention and treatment of gastric cancer

BACKGROUND

Advanced gastric cancer remains a significant global health challenge, with limited therapeutic options available. In contrast, immunotherapy have emerged as promising alternatives, offering greater potency in treating advanced gastric cancer. However, the development of novel and efficient immunotherapeutic strategy is crucial to enhance the body's immune response against gastric cancer.

METHODS

This study developed a single-injection peptide hydrogel-based nanovaccine therapy for gastric cancer treatment. The therapy utilizes a RADA32 peptide hydrogel, which is sensitive to metal ion concentration, to encapsulate manganese ions and HPPS nanovaccines. The HPPS nanovaccines contain antigen peptide and CpG-ODN, designed to activate both the toll-like receptor 9 (TLR9) and cGAS-STING signaling pathways in antigen-presenting cells. This design aims to facilitate a stable and sustained release of the nanovaccine, thereby enhancing the body's effective recognition and response to antigens.

RESULTS

The efficacy of the system was confirmed using the model antigen OVA and the gastric cancer-specific antigen MG7-related peptide. The results demonstrated that the nanovaccine effectively activated the immune response, leading to enhanced recognition and response to the antigens. This activation of both TLR9 and cGAS-STING pathways in antigen-presenting cells was crucial for the observed immune response, highlighting the potential of this approach to stimulate a robust and sustained immune response against gastric cancer.

CONCLUSIONS

This study presents a novel strategy for clinical anti-tumor vaccine administration, offering a promising approach for the prevention and treatment of gastric cancer. The single-injection peptide hydrogel-based nanovaccine system provides a convenient and effective method to enhance the body's immune response against gastric cancer. This approach could potentially be expanded to other types of cancer, providing a versatile platform for cancer immunotherapy.

Intrinsic immunomodulatory hydrogels for chronic inflammation

The immune system plays a pivotal role in maintaining physiological homeostasis and influencing disease processes. Dysregulated immune responses drive chronic inflammation, which in turn results in a range of diseases that are among the leading causes of death globally. Traditional immune interventions, which aim to regulate either insufficient or excessive inflammation, frequently entail lifelong comorbidities and the risk of severe side effects. In this context, intrinsic immunomodulatory hydrogels, designed to precisely control the local immune microenvironment, have recently attracted increasing attention. In particular, these advanced hydrogels not only function as delivery mechanisms but also actively engage in immune modulation, optimizing interactions with the immune system for enhanced tissue repair, thereby providing a sophisticated strategy for managing chronic inflammation. In this tutorial review, we outline key elements of chronic inflammation and subsequently explore the strategic design principles of intrinsic immunomodulatory hydrogels based on these elements. Finally, we examine the challenges and prospects of such immunomodulatory hydrogels, which are expected to inspire further preclinical research and clinical translation in addressing chronic inflammation.

Purification of Enzymatically Active Xrn1 for Removal of Non-capped mRNAs from In Vitro Transcription Reactions and Evaluation of mRNA Decapping Status In Vivo

The cap is a 7-methylguanosine attached to the first messenger RNA (mRNA) nucleotide with a 5'-5' triphosphate bridge. This conserved eukaryotic modification confers stability to the transcripts and is essential for translation initiation. The specific mechanisms that govern transcript cytoplasmic longevity and translatability were always of substantial interest. Multiple works aimed at modeling mRNA decay mechanisms, including the onset of decapping, which is the rate-limiting step of mRNA decay. Additionally, with the recent advances in RNA-based vaccines, the importance of efficient synthesis of fully functional mRNAs has increased. Non-capped mRNAs arising during in vitro transcription are highly immunogenic, and multiple approaches were developed to reduce their levels. Efficient and low-cost methods for elimination of non-capped mRNAs in vitro are therefore essential to basic sciences and to pharmaceutical applications. Here, we present a protocol for heterologous expression and purification of catalytically active recombinant Xrn1 from Thermothelomyces (Myceliophthora) thermophilus (Tt_Xrn1). We also describe protocols needed to verify the enzyme quality.

Polystyrene-Poly(acrylic acid) Block Copolymers for Encapsulation of Butyrylcholinesterase into Injectable Nanoreactors

The article is devoted to the creation of enzymatic nanoreactors based on polystyrene-block-poly(acrylic acid) (PS-b-PAA) copolymers containing bioscavengers capable of neutralizing toxic esters both in the body and in the environment. Block copolymers of different amphiphilicity, hydrophilicity and molecular weights were synthesized and characterized using gel permeation chromatography, NMR and UV spectroscopy. Polymeric nanocontainers in the absence and presence of human butyrylcholinesterase were made by film hydration and characterized by dynamic light scattering and microscopy methods. Enzyme activity was determined using the Ellman method. For the first time, factors that need to be taken into account for the creation of effective enzymatic nanoreactors based on PS-b-PAA are presented. The data obtained open up the possibility of PS-b-PAA nanoreactor use for future in vivo bioscavenger studies.

Biomedical Promise of Aspergillus Flavus-Biosynthesized Selenium Nanoparticles: A Green Synthesis Approach to Antiviral, Anticancer, Anti-Biofilm, and Antibacterial Applications

This study utilized Aspergillus flavus to produce selenium nanoparticles (Se-NPs) in an environmentally friendly and ecologically sustainable manner, targeting several medicinal applications. These biosynthesized Se-NPs were meticulously characterized using X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscope (TEM), and UV-visible spectroscopy (UV), revealing their spherical shape and size ranging between 28 and 78 nm. We conducted further testing of Se-NPs to evaluate their potential for biological applications, including antiviral, anticancer, antibacterial, antioxidant, and antibiofilm activities. The results indicate that biosynthesized Se-NPs could be effective against various pathogens, including Salmonella typhimurium (ATCC 14028), Bacillus pumilus (ATCC 14884), Staphylococcus aureus (ATCC 6538), Clostridium sporogenes (ATCC 19404), Escherichia coli (ATCC 8739), and Bacillus subtilis (ATCC 6633). Additionally, the biosynthesized Se-NPs exhibited anticancer activity against three cell lines: pancreatic carcinoma (PANC1), cervical cancer (Hela), and colorectal adenocarcinoma (Caco-2), with IC50 values of 177, 208, and 216 μg/mL, respectively. The nanoparticles demonstrated antiviral activity against HSV-1 and HAV, achieving inhibition rates of 66.4% and 15.1%, respectively, at the maximum non-toxic concentration, while also displaying antibiofilm and antioxidant properties. In conclusion, the biosynthesized Se-NPs by A. flavus present a promising avenue for various biomedical applications with safe usage.

Nanoparticle-based Gene Therapy for Neurodegenerative Disorders

Neurological disorders present a formidable challenge in modern medicine due to the intricate obstacles set for the brain and the multipart nature of genetic interventions. This review article delves into the promising realm of nanoparticle-based gene therapy as an innovative approach to addressing the intricacies of neurological disorders. Nanoparticles (NPs) provide a multipurpose podium for the conveyance of therapeutic genes, offering unique properties such as precise targeting, enhanced stability, and the potential to bypass blood-brain barrier (BBB) restrictions. This comprehensive exploration reviews the current state of nanoparticle-mediated gene therapy in neurological disorders, highlighting recent advancements and breakthroughs. The discussion encompasses the synthesis of nanoparticles from various materials and their conjugation to therapeutic genes, emphasizing the flexibility in design that contributes to specific tissue targeting. The abstract also addresses the low immunogenicity of these nanoparticles and their stability in circulation, critical factors for successful gene delivery. While the potential of NP-based gene therapy for neurological disorders is vast, challenges and gaps in knowledge persist. The lack of extensive clinical trials leaves questions about safety and potential side effects unanswered. Therefore, this abstract emphasizes the need for further research to validate the therapeutic applications of NP-mediated gene therapy and to address nanosafety concerns. In conclusion, nanoparticle-based gene therapy emerges as a promising avenue in the pursuit of effective treatments for neurological disorders. This abstract advocates for continued research efforts to bridge existing knowledge gaps, unlocking the full potential of this innovative approach and paving the way for transformative solutions in the realm of neurological health.

The zebrafish as a potential model for vaccine and adjuvant development

INTRODUCTION

Zebrafishes represent a proven model for human diseases and systems biology, exhibiting physiological and genetic similarities and having innate and adaptive immune systems. However, they are underexplored for human vaccinology, vaccine development, and testing. Here we summarize gaps and challenges.

AREAS COVERED

Zebrafish models have four potential applications: 1) Vaccine safety: The past successes in using zebrafishes to test xenobiotics could extend to vaccine and adjuvant formulations for general safety or target organs due to the zebrafish embryos' optical transparency. 2) Innate immunity: The zebrafish offers refined ways to examine vaccine effects through signaling via Toll-like or NOD-like receptors in zebrafish myeloid cells. 3) Adaptive immunity: Zebrafishes produce IgM, IgD,and two IgZ immunoglobulins, but these are understudied, due to a lack of immunological reagents for challenge studies. 4) Systems vaccinology: Due to the availability of a well-referenced zebrafish genome, transcriptome, proteome, and epigenome, this model offers potential here.

EXPERT OPINION

It remains unproven whether zebrafishes can be employed for testing and developing human vaccines. We are still at the hypothesis-generating stage, although it is possible to begin outlining experiments for this purpose. Through transgenic manipulation, zebrafish models could offer new paths for shaping animal models and systems vaccinology.