Enhanced Postsurgical Cancer Treatment Using Methacrylated Glycol Chitosan Hydrogel for Sustained DNA/Doxorubicin Delivery and Immunotherapy

Background: Cancer recurrence and metastasis are major contributors to treatment failure following tumor resection surgery. We developed a novel implantable drug delivery system utilizing glycol chitosan to address these issues. Glycol chitosan is a natural adjuvant, inducing dendritic cell activation to promote T helper 1 cell immune responses, macrophage activation, and cytokine production. Effective antigen production by dendritic cells initiates T-cell-mediated immune responses, aiding tumor growth control. Methods: In this study, we fabricated multifunctional methacrylated glycol chitosan (MGC) hydrogels with extended release of DNA/doxorubicin (DOX) complex for cancer immunotherapy. We constructed the resection model of breast cancer to verify the anticancer effects of MGC hydrogel with DNA/DOX complex. Results: This study demonstrated the potential of MGC hydrogel with extended release of DNA/DOX complex for local and efficient cancer therapy. The MGC hydrogel was implanted directly into the surgical site after tumor resection, activating tumor-related immune cells both locally and over a prolonged period of time through immune-reactive molecules. Conclusions: The MGC hydrogel effectively suppressed tumor recurrence and metastasis while enhancing immunotherapeutic efficacy and minimizing side effects. This biomaterial-based drug delivery system, combined with cancer immunotherapy, can substantial improve treatment outcomes and patient prognosis.

Polymeric DNase-I nanozymes targeting neutrophil extracellular traps for the treatment of bowel inflammation

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a family of chronic disorders along the gastrointestinal tract. Because of its idiopathic nature, IBD does not have a fundamental cure; current available therapies for IBD are limited to prolonged doses of immunomodulatory agents. While these treatments may reduce inflammation, limited therapeutic efficacy, inconsistency across patients, and adverse side effects from aggressive medications remain as major drawbacks. Recently, excessive production and accumulation of neutrophil extracellular traps (NETs) also known as NETosis have been identified to exacerbate inflammatory responses and induce further tissue damage in IBD. Such discovery invited many researchers to investigate NETs as a potential therapeutic target. DNase-I is a natural agent that can effectively destroy NETs and, therefore, potentially reduce NETs-induced inflammations even without the use of aggressive drugs. However, low stability and rapid clearance of DNase-I remain as major limitations for further therapeutic applications. In this research, polymeric nanozymes were fabricated to increase the delivery and therapeutic efficacy of DNase-I. DNase-I was immobilized on the surface of polymeric nanoparticles to maintain its enzymatic properties while extending its activity in the colon. Delivery of DNase-I using this platform allowed enhanced stability and prolonged activity of DNase-I with minimal toxicity. When administered to animal models of IBD, DNase-I nanozymes successfully alleviated various pathophysiological symptoms of IBD. More importantly, DNase-I nanozyme administration successfully attenuated neutrophil infiltration and NETosis in the colon compared to free DNase-I or mesalamine.

Biofunctional Inorganic Layered Double Hydroxide Nanohybrid Enhances Immunotherapeutic Effect on Atopic Dermatitis Treatment

Atopic dermatitis (AD) is a widespread, recurrent, and chronic inflammatory skin condition that imposes a major burden on patients. Conventional treatments, such as corticosteroids, are associated with various side effects, underscoring the need for innovative therapeutic approaches. In this study, the possibility of using indole-3-acetic acid-loaded layered double hydroxides (IAA-LDHs) is evaluated as a novel treatment for AD. IAA is an auxin-class plant hormone with antioxidant and anti-inflammatory effects. Following the synthesis of IAA-LDH nanohybrids, their ability to induce M2-like macrophage polarization in macrophages obtained from mouse bone marrow is assessed. The antioxidant activity of IAA-LDH is quantified by assessing the decrease in intracellular reactive oxygen species levels. The anti-inflammatory and anti-atopic characteristics of IAA-LDH are evaluated in a mouse model of AD by examining the cutaneous tissues, immunological organs, and cells. The findings suggest that IAA-LDH has great therapeutic potential as a candidate for AD treatment based on its in vitro and in vivo modulation of AD immunology, enhancement of macrophage polarization, and antioxidant activity. This inorganic drug delivery technology represents a promising new avenue for the development of safe and effective AD treatments.

Uniform Gold Nanostructure Formation via Weakly Adsorbed Gold Films and Thermal Annealing for Reliable Localized Surface Plasmon Resonance-Based Detection of DNase-I

Deoxyribonuclease-I (DNase-I), a representative endonuclease, is an important biomarker for the diagnosis of infectious diseases and cancer progression. However, enzymatic activity decreases rapidly ex vivo, which highlights the need for precise on-site detection of DNase-I. Here, a localized surface plasmon resonance (LSPR) biosensor that enables the simple and rapid detection of DNase-I is reported. Moreover, a novel technique named electrochemical deposition and mild thermal annealing (EDMIT) is applied to overcome signal variations. By taking advantage of the low adhesion of gold clusters on indium tin oxide substrates, both the uniformity and sphericity of gold nanoparticles are increased under mild thermal annealing conditions via coalescence and Ostwald ripening. This ultimately results in an approximately 15-fold decrease in LSPR signal variations. The linear range of the fabricated sensor is 20-1000 ng mL-1 with a limit of detection (LOD) of 127.25 pg mL-1 , as demonstrated by spectral absorbance analyses. The fabricated LSPR sensor stably measured DNase-I concentrations from samples collected from both an inflammatory bowel disease (IBD) mouse model, as well as human patients with severe COVID-19 symptoms. Therefore, the proposed LSPR sensor fabricated via the EDMIT method can be used for early diagnosis of other infectious diseases.

Lipid nanoparticle-based mRNA delivery systems for cancer immunotherapy

Cancer immunotherapy, which harnesses the power of the immune system, has shown immense promise in the fight against malignancies. Messenger RNA (mRNA) stands as a versatile instrument in this context, with its capacity to encode tumor-associated antigens (TAAs), immune cell receptors, cytokines, and antibodies. Nevertheless, the inherent structural instability of mRNA requires the development of effective delivery systems. Lipid nanoparticles (LNPs) have emerged as significant candidates for mRNA delivery in cancer immunotherapy, providing both protection to the mRNA and enhanced intracellular delivery efficiency. In this review, we offer a comprehensive summary of the recent advancements in LNP-based mRNA delivery systems, with a focus on strategies for optimizing the design and delivery of mRNA-encoded therapeutics in cancer treatment. Furthermore, we delve into the challenges encountered in this field and contemplate future perspectives, aiming to improve the safety and efficacy of LNP-based mRNA cancer immunotherapies.

Reprogramming the tumor microenvironment with biotechnology

The tumor microenvironment (TME) is a unique environment that is developed by the tumor and controlled by tumor-induced interactions with host cells during tumor progression. The TME includes immune cells, which can be classified into two types: tumor- antagonizing and tumor-promoting immune cells. Increasing the tumor treatment responses is associated with the tumor immune microenvironment. Targeting the TME has become a popular topic in research, which includes polarizing macrophage phenotype 2 into macrophage phenotype 1 using Toll-like receptor agonists with cytokines, anti-CD47, and anti-SIPRα. Moreover, inhibiting regulatory T cells through blockades and depletion restricts immunosuppressive cells in the TME. Reprogramming T cell infiltration and T cell exhaustion improves tumor infiltrating lymphocytes, such as CD8⁺ or CD4⁺ T cells. Targeting metabolic pathways, including glucose, lipid, and amino acid metabolisms, can suppress tumor growth by restricting the absorption of nutrients and adenosine triphosphate energy into tumor cells. In conclusion, these TME reprogramming strategies exhibit more effective responses using combination treatments, biomaterials, and nanoparticles. This review highlights how biomaterials and immunotherapy can reprogram TME and improve the immune activity.

Impact of the conjugation of antibodies to the surfaces of polymer nanoparticles on the immune cell targeting abilities

Antibodies have been widely used to provide targeting ability and to enhance bioactivity owing to their high specificity, availability, and diversity. Recent advances in biotechnology and nanotechnology permit site-specific engineering of antibodies and their conjugation to the surfaces of nanoparticles (NPs) in various orientations through chemical conjugations and physical adhesions. This study proposes the conjugation of poly(lactic-co-glycolic acid) (PLGA) NPs with antibodies by using two distinct methods, followed by a comparison between the cell-targeting efficiencies of both techniques. Full-length antibodies were conjugated to the PLGA-poly(ethylene glycol)-carboxylic acid (PLGA-PEG-COOH) NPs through the conventional carbodiimide coupling reaction, and f(ab')2 antibody fragments were conjugated to the PLGA-poly(ethylene glycol)-maleimide(PLGA-PEG-Mal) NPs through interactions between the f(ab')2 fragment thiol groups and the maleimide located on the nanoparticle surface. The results demonstrate that the PLGA nanoparticles conjugated with the f(ab')2 antibody fragments had a higher targeting efficiency in vitro and in vivo than that of the PLGA nanoparticles conjugated with the full-length antibodies. The results of this study can be built upon to design a delivery technique for drugs through biocompatible nanoparticles.