Micellar structure of decenyl succinic anhydride modified pullulan with degree of substitution dependence in aqueous solution

A broad distribution pullulan (PUL) sample was hydrophobically modified by a relative longer decenyl succinic anhydride (DCSA) side chains with seven different degree of substitution (DS) to obtain the PUL-DCSA. The micellar structure of PUL-DCSA with DS dependence was investigated by pyrene-probe fluorescence and small-angle X-ray scattering (SAXS) in 0.05 M aqueous NaCl. While PUL-DCSA with DS > 0.26, both the SAXS and fluorescence results can be explained by the flower necklace model, when DS < 0.26, PUL-DCSA forms the loose flower necklace model. Moreover, the micellar structure of PUL-DCSA characterized by SAXS and fluorescence was different from that of the PUL-bearing shorter alkyl (octenyl or nonenyl) chains. The smaller chain stiffness qFN and larger number of monomer (glucose residues) per unit flower micelle N0u of PUL-DCSA, mainly due to the difference in the different hydrophobic alkyl side chains. This research will provide a theoretical guidance for designing biomedical materials with appropriate scale and characteristic functions in drug delivery system.

Enhanced diabetic foot ulcer treatment with a chitosan-based thermosensitive hydrogel loaded self-assembled multi-functional nanoparticles for antibacterial and angiogenic effects

Inhibiting bacterial growth and promoting angiogenesis are essential for enhancing wound healing in diabetic patients. Excessive oxidative stress at the wound site can also lead to an accumulation of reactive oxygen species. To address these challenges, a smart thermosensitive hydrogel loaded with therapeutic agents was developed. This formulation features self-assembled nanoparticles named CIZ, consisting of chlorogenic acid (CA), indocyanine green (ICG), and zinc ions (Zn2+). These nanoparticles are loaded into a chitosan-β-glycerophosphate hydrogel, named CIZ@G, which enables rapid gel formation under photothermal effects. The hydrogel demonstrates good biocompatibility and effectively releases drugs into diabetic foot ulcers (DFU) wound. Benefiting from the dual actions of CA and zinc ions, the hydrogel exhibits potent antioxidative and anti-inflammatory effects, enhances the expression of vascular endothelial growth factor (VEGF) and Platelet endothelial cell adhesion molecule-1 (CD31), and promotes angiogenesis. Both in vitro and in vivo experiments confirm that CIZ@G can effectively inhibit the growth of Staphylococcus aureus post-laser irradiation and accelerate wound remodeling within 14 days. This approach offers a new strategy for the treatment of diabetic foot ulcers (DFU), potentially transforming patient care in this challenging clinical area.

Multilayered hydrogel scaffold construct with native tissue matched elastic modulus: A regenerative microenvironment for urethral scar-free healing

The unsuitable deformation stimulus, harsh urine environment, and lack of a regenerative microenvironment (RME) prevent scaffold-based urethral repair and ultimately lead to irreversible urethral scarring. The researchers clarify the optimal elastic modulus of the urethral scaffolds for urethral repair and design a multilayered PVA hydrogel scaffold for urethral scar-free healing. The inner layer of the scaffold has self-healing properties, which ensures that the wound effectively resists harsh urine erosion, even when subjected to sutures. In addition, the scaffold's outer layer has an extracellular matrix-like structure that synergizes with adipose-derived stem cells to create a favorable RME. In vivo experiments confirm successful urethral scar-free healing using the PVA multilayered hydrogel scaffold. Further mechanistic study shows that the PVA multilayer hydrogel effectively resists the urine-induced inflammatory response and accelerates the transition of urethral wound healing to the proliferative phase by regulating macrophage polarization, thus providing favorable conditions for urethral scar-free healing. This study provides mechanical criteria for the fabrication of urethral tissue-engineered scaffolds, as well as important insights into their design.

A computer-aided, heterodimer-based "triadic" carrier-free drug delivery platform to mitigate multidrug resistance in lung cancer and enhance efficiency

Co-delivering multiple drugs or circumventing the drug efflux mechanism can significantly decrease multidrug resistance (MDR), a major cause of cancer treatment failure. In this study, we designed and fabricated a universal "three-in-one" self-delivery system for synergistic cancer therapy using a computer-aided strategy. First, we engineered two glutathione (GSH)-responsive heterodimers, ERL-SS-CPT (erlotinib [ERL] linked with camptothecin [CPT] via a disulfide bond [SS]) and CPT-SS-ERI (CPT conjugated with erianin [ERI]), which serve as both cargo and carrier material. Next, molecular dynamics simulations indicated that multiple noncovalent molecular forces, including π-π stacking, hydrogen bonds, hydrophobic interactions, and sulfur bonds, drive the self-assembly process of these heterodimers. We then explored the universality of the heterodimers and developed a "triadic" drug delivery platform comprising 40 variants. Subsequently, we conducted case studies on docetaxel (DTX)-loaded ERL-SS-CPT nanoparticles (denoted as DTX@ERL-SS-CPT NPs) and curcumin (CUR)-loaded ERL-SS-CPT NPs (identified as CUR@CPT-SS-ERI NPs) to comprehensively investigate their self-assembly mechanism, physicochemical properties, storage stability, GSH-responsive drug release, cellular uptake, apoptosis effects, biocompatibility, and cytotoxicity. Both NPs exhibited well-defined spherical structures, high drug loading rates, and excellent storage stability. DTX@ERL-SS-CPT NPs exhibited the strongest cytotoxicity in A549 cells, following the order of DTX@ERL-SS-CPT NPs > ERL-SS-CPT NPs > CPT > DTX > ERL. Conversely, DTX@ERL-SS-CPT NPs showed negligible cytotoxicity in normal human bronchial epithelium cell line (BEAS-2B), indicating good biocompatibility and safety. Similar observations were made for CUR@CPT-SS-ERI NPs regarding biocompatibility and cytotoxicity. Upon endocytosis and encountering intracellular overexpressed GSH, the disulfide-bond linker is cleaved, resulting in the release of the versatile NPs into three parts. The spherical NPs enhance water solubility, reduce the required dosage of free drugs, and increase cellular drug accumulation while suppressing P-glycoprotein (P-gp) expression, leading to apoptosis. This work provides a computer-aided universal strategy-a heterodimer-based "triadic" drug delivery platform-to enhance anticancer efficiency while reducing multidrug resistance.

Vaccine approaches to treat urothelial cancer

Bladder cancer (BC) accounts for about 4% of all malignancies. Non-muscle-invasive BC, 75% of cases, is treated with transurethral resection and adjuvant intravesical instillation, while muscle-invasive BC warrants cisplatin-based perioperative chemotherapy. Although immune-checkpoint inhibitors, antibody drug conjugates and targeted agents have provided dramatic advances, metastatic BC remains a generally incurable disease and clinical trials continue to vigorously evaluate novel molecules. Cancer vaccines aim at activating the patient's immune system against tumor cells. Several means of delivering neoantigens have been developed, including peptides, antigen-presenting cells, virus, or nucleic acids. Various improvements are constantly being explored, such as adjuvants use and combination strategies. Nucleic acids-based vaccines are increasingly gaining attention in recent years, with promising results in other malignancies. However, despite the recent advantages, numerous obstacles persist. This review is aimed at describing the different types of cancer vaccines, their evaluations in UC patients and the more recent innovations in this field.

Lipid Nanovesicle Platforms for Hepatocellular Carcinoma Precision Medicine Therapeutics: Progress and Perspectives

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality globally. HCC is highly heterogenous with diverse etiologies leading to different driver mutations potentiating unique tumor immune microenvironments. Current therapeutic options, including immune checkpoint inhibitors and combinations, have achieved limited objective response rates for the majority of patients. Thus, a precision medicine approach is needed to tailor specific treatment options for molecular subsets of HCC patients. Lipid nanovesicle platforms, either liposome- (synthetic) or extracellular vesicle (natural)-derived present are improved drug delivery vehicles which may be modified to contain specific cargos for targeting specific tumor sites, with a natural affinity for liver with limited toxicity. This mini-review provides updates on the applications of novel lipid nanovesicle-based therapeutics for HCC precision medicine and the challenges associated with translating this therapeutic subclass from preclinical models to the clinic.

Long-term stability and immunogenicity of lipid nanoparticle COVID-19 mRNA vaccine is affected by particle size

Messenger ribonucleic acid (mRNA) technology has been rapidly applied for the development of the COVID-19 vaccine. However, naked mRNA itself is inherently unstable. Lipid nanoparticles (LNPs) protect mRNAs from extracellular ribonucleases and facilitate mRNA trafficking. For mRNA vaccines, antigen-presenting cells utilize LNPs through uptake to elicit antigen-specific immunity. There are reports on the impact of various physical characteristics of LNPs, particularly those with sizes less than 200 nm, especially 50 to 150 nm, on the overall stability and protective efficacy of mRNA vaccines. To address this, a single change in the size of LNPs using the same mRNA stock solution was assessed for the physicochemical characterization of the resulting mRNA-LNPs vaccine, along with the evaluation of their protective efficacy. Particles of smaller sizes generally disperse more effectively in solutions, with minimized occurrence of particle precipitation and aggregation. Here, we demonstrate that the vaccine containing 80-100 nm mRNA-LNPs showed the best stability and protection at 4°C and -20°C. Furthermore, we can conclude that freezing the vaccine at -20°C is more appropriate for maintaining stability over the long term. This effort is poised to provide a scientific basis for improving the quality of ongoing mRNA vaccine endeavors and providing information on the development of novel products.

A highly neutralizing human monoclonal antibody targeting a novel linear epitope on staphylococcal enterotoxin B

Staphylococcal Enterotoxin B (SEB), produced by Staphylococcus aureus (S. aureus), is a powerful superantigen that induces severe immune disruption and toxic shock syndrome (TSS) upon binding to MHC-II and TCR. Despite its significant impact on the pathogenesis of S. aureus, there are currently no specific therapeutic interventions available to counteract the mechanism of action exerted by this toxin. In this study, we have identified a human monoclonal antibody, named Hm0487, that specifically targets SEB by single-cell sequencing using PBMCs isolated from volunteers enrolled in a phase I clinical trial of the five-antigen S. aureus vaccine. X-ray crystallography studies revealed that Hm0487 exhibits high affinity for a linear B cell epitope in SEB (SEB138-147), which is located distantly from the site involved in the formation of the MHC-SEB-TCR ternary complex. Furthermore, in vitro studies demonstrated that Hm0487 significantly impacts the interaction of SEB with both receptors and the binding to immune cells, probably due to an allosteric effect on SEB rather than competing with receptors for binding sites. Moreover, both in vitro and in vivo studies validated that Hm0487 displayed efficient neutralizing efficacy in models of lethal shock and sepsis induced by either SEB or bacterial challenge. Our findings unveil an alternative mechanism for neutralizing the pathogenesis of SEB by Hm0487, and this antibody provides a novel strategy for mitigating both SEB-induced toxicity and S. aureus infection.

Toll-like receptor agonists as cancer vaccine adjuvants

Cancer immunotherapy has emerged as a promising strategy to treat cancer patients. Among the wide range of immunological approaches, cancer vaccines have been investigated to activate and expand tumor-reactive T cells. However, most cancer vaccines have not shown significant clinical benefit as monotherapies. This is likely due to the antigen targets of vaccines, "self" proteins to which there is tolerance, as well as to the immunosuppressive tumor microenvironment. To help circumvent immune tolerance and generate effective immune responses, adjuvants for cancer vaccines are necessary. One representative adjuvant family is Toll-Like receptor (TLR) agonists, synthetic molecules that stimulate TLRs. TLRs are the largest family of pattern recognition receptors (PRRs) that serve as the sensors of pathogens or cellular damage. They recognize conserved foreign molecules from pathogens or internal molecules from cellular damage and propel innate immune responses. When used with vaccines, activation of TLRs signals an innate damage response that can facilitate the development of a strong adaptive immune response against the target antigen. The ability of TLR agonists to modulate innate immune responses has positioned them to serve as adjuvants for vaccines targeting infectious diseases and cancers. This review provides a summary of various TLRs, including their expression patterns, their functions in the immune system, as well as their ligands and synthetic molecules developed as TLR agonists. In addition, it presents a comprehensive overview of recent strategies employing different TLR agonists as adjuvants in cancer vaccine development, both in pre-clinical models and ongoing clinical trials.

3D evaluation of the extracellular matrix of hypoxic pancreatic islets using light sheet fluorescence microscopy

Pancreatic islet transplantation is a promising treatment for type 1 diabetes, but the survival and function of transplanted islets are hindered by the loss of extracellular matrix (ECM) during islet isolation and by low oxygenation upon implantation. This study aimed to evaluate the impact of hypoxia on ECM using a cutting-edge imaging approach based on tissue clearing and 3D microscopy. Human and rat islets were cultured under normoxic (O2 21%) or hypoxic (O2 1%) conditions. Immunofluorescence staining targeting insulin, glucagon, CA9 (a hypoxia marker), ECM proteins (collagen 4, fibronectin, laminin), and E-cadherin (intercellular adhesion protein) was performed on fixed whole islets. The cleared islets were imaged using Light Sheet Fluorescence Microscopy (LSFM) and digitally analyzed. The volumetric analysis of target proteins did not show significant differences in abundance between the experimental groups. However, 3D projections revealed distinct morphological features that differentiated normoxic and hypoxic islets. Under normoxic conditions, ECM could be found throughout the islets. Hypoxic islets exhibited areas of scattered nuclei and central clusters of ECM proteins, indicating central necrosis. E-cadherin was absent in these areas. Our results, demonstrating a diminution of islets' functional mass in hypoxia, align with the functional decline observed in transplanted islets experiencing low oxygenation after grafting. This study provides a methodology combining tissue clearing, multiplex immunofluorescence, Light Sheet Fluorescence Microscopy, and digital image analysis to investigate pancreatic islet morphology. This 3D approach allowed us to highlight ECM organizational changes during hypoxia from a morphological perspective.

WYC-209 inhibited GC malignant progression by down-regulating WNT4 through RARα

Gastric cancer (GC) has been a major health burden all over the world but there are fewer promising chemotherapeutic drugs due to its multidrug resistance. It has been reported that WYC-209 suppresses the growth and metastasis of tumor-repopulating cells but the effect on GC was not explored. MTT, colony formation, and transwell assays were performed to examine the effects of WYC-209 on the proliferation, colony growth, and mobility of GC cells. Western blotting and qRT-PCR were used to detect the expression of proteins and mRNA. RNA-seq and enrichment analyses were conducted for the differentially expressed genes and enriched biological processes and pathways. The rescue experiments were carried out for further validation. Besides, we constructed xenograft model to confirm the effect of WYC-209 in vivo. The dual-luciferase reporter and Chromatin immunoprecipitation were implemented to confirm the underlying mechanism. WYC-209 exerted excellent anti-cancer effects both in vitro and in vivo. Based on RNA-seq and enrichment analyses, we found that Wnt family member 4 (WNT4) was significantly down-regulated. More importantly, WNT4 overexpression breached the inhibitory effect of WYC-209 on GC progression. Mechanically, WYC-209 significantly promoted the binding between retinoic acid receptor α (RARα) and WNT4 promoter. WYC-209 exerts anti-tumor effects in GC by down-regulating the expression of WNT4 via RARα.

Decoding trends in mRNA vaccine research: A comprehensive bibliometric study

BACKGROUND

In recent years, infectious diseases like COVID-19 have had profound global socio-economic impacts. mRNA vaccines have gained prominence due to their rapid development, industrial adaptability, simplicity, and responsiveness to new variants. Notably, the 2023 Nobel Prize in Physiology or Medicine recognized significant contributions to mRNA vaccine research.

METHODS

Our study employed a comprehensive bibliometric analysis using the Web of Science Core Collection (WoSCC) database, encompassing 5,512 papers on mRNA vaccines from 2003 to 2023. We generated cooperation maps, co-citation analyses, and keyword clustering to evaluate the field's developmental history and achievements.

RESULTS

The analysis yielded knowledge maps highlighting countries/institutions, influential authors, frequently published and highly cited journals, and seminal references. Ongoing research hotspots encompass immune responses, stability enhancement, applications in cancer prevention and treatment, and combating infectious diseases using mRNA technology.

CONCLUSIONS

mRNA vaccines represent a transformative development in infectious disease prevention. This study provides insights into the field's growth and identifies key research priorities, facilitating advancements in vaccine technology and addressing future challenges.

Exosome may be the next generation of promising cell-free vaccines

Traditional vaccines have limits against some persistent infections and pathogens. The development of novel vaccine technologies is particularly critical for the future. Exosomes play an important role in physiological and pathological processes. Exosomes present many advantages, such as inherent capacity being biocompatible, non-toxic, which make them a more desirable candidate for vaccines. However, research on exosomes are in their infancy and the barriers of low yield, low purity, and weak targeting of exosomes limit their applications in vaccines. Accordingly, further exploration is necessary to improve these problems and subsequently facilitate the functional studies of exosomes. In this study, we reviewed the origin, classification, functions, modifications, separation and purification, and characterization methods of exosomes. Meanwhile, we focused on the role and mechanism of exosomes for cancer and COVID-19 vaccines.

Equivalence of freeze-dried and liquid-frozen formulations of MVA-BN as smallpox and mpox vaccine

Modified Vaccinia Ankara Bavarian Nordic (MVA-BN) as a smallpox and mpox vaccine has been approved in its liquid-frozen (LF) formulation in the US, Canada, and EU. A freeze-dried (FD) formulation may offer additional benefits, such as a longer shelf life and reduced dependence on cold chain storage and transport. In a phase 2 clinical trial, 651 vaccinia-naïve participants were vaccinated with two doses of MVA-BN LF or FD, 4 weeks apart. The objectives were to compare MVA-BN FD with LF in terms of vaccine-induced immune responses, safety, and reactogenicity. Non-inferiority of the immune response was assessed by the 95% CI of the geometric mean ratios. Both formulations induced robust vaccinia-specific humoral and cellular immune responses. At peak humoral responses (Week 6), geometric means of total antibody titers were 1096 (95% CI 1013, 1186) from the FD group and 877 (95% CI 804, 956) from the LF group, achieving the primary endpoint of non-inferiority of MVA-BN FD compared to MVA-BN LF. At peak cellular responses (Week 2), geometric means of T cell spot forming units were 449 (95% CI 341, 590) from the FD group and 316 (95% CI 234, 427) from the LF group. Both formulations of MVA-BN were well tolerated, with similar unsolicited AEs and solicited systemic reactions in both groups but slightly more local reactions in the FD group. No vaccine-related serious adverse events (SAEs) or vaccine-related AE of special interest were reported. The FD formulation of MVA-BN was shown to be equivalent to MVA-BN LF.

Immunotherapy and delivery systems for melanoma

Melanoma is a highly malignant tumor of melanocyte origin that is prone to early metastasis and has a very poor prognosis. Early melanoma treatment modalities are mainly surgical, and treatment strategies for advanced or metastatic melanoma contain chemotherapy, radiotherapy, targeted therapy and immunotherapy. The efficacy of chemotherapy and radiotherapy has been unsatisfactory due to low sensitivity and strong toxic side effects. And targeted therapy is prone to drug resistance, so its clinical application is limited. Melanoma has always been the leader of immunotherapy for solid tumors, and how to maximize the role of immunotherapy and how to implement immunotherapy more accurately are still urgent to be explored. This review summarizes the common immunotherapies and applications for melanoma, illustrates the current research status of melanoma immunotherapy delivery systems, and discusses the advantages and disadvantages of each delivery system and its prospects for clinical application.

The contributions of T cell-mediated immunity to protection from vaccine-preventable diseases: A primer

In the face of the ever-present burden of emerging and reemerging infectious diseases, there is a growing need to comprehensively assess individual- and population-level immunity to vaccine-preventable diseases (VPDs). Many of these efforts, however, focus exclusively on antibody-mediated immunity, ignoring the role of T cells. Aimed at clinicians, public health practioners, and others who play central roles in human vaccine research but do not have formal training in immunology, we review how vaccines against infectious diseases elicit T cell responses, what types of vaccines elicit T cell responses, and how T cell responses are measured. We then use examples to demonstrate six ways that T cells contribute to protection from VPD, including directly mediating protection, enabling antibody responses, reducing disease severity, increasing cross-reactivity, improving durability, and protecting special populations. We conclude with a discussion of challenges and solutions to more widespread consideration of T cell responses in clinical vaccinology.

Clinical development of SpikoGen®, an Advax-CpG55.2 adjuvanted recombinant spike protein vaccine

Recombinant protein vaccines represent a well-established, reliable and safe approach for pandemic vaccination. SpikoGen® is a recombinant spike protein trimer manufactured in insect cells and formulated with Advax-CpG55.2 adjuvant. In murine, hamster, ferret and non-human primate studies, SpikoGen® consistently provided protection against a range of SARS-CoV-2 variants. A pivotal Phase 3 placebo-controlled efficacy trial involving 16,876 participants confirmed the ability of SpikoGen® to prevent infection and severe disease caused by the virulent Delta strain. SpikoGen® subsequently received a marketing authorization from the Iranian FDA in early October 2021 for prevention of COVID-19 in adults. Following a successful pediatric study, its approval was extended to children 5 years and older. Eight million doses of SpikoGen® have been delivered, and a next-generation booster version is currently in development. This highlights the benefits of adjuvanted protein-based approaches which should not overlook when vaccine platforms are being selected for future pandemics.

Biomarkers of mature neuronal differentiation and related diseases

The nervous system regulates perception, cognition and behavioral responses by serving as the body's primary communication system for receiving, regulating and transmitting information. Neurons are the fundamental structures and units of the nervous system. Their differentiation and maturation processes rely on the expression of specific biomarkers. Neuron-specific intracellular markers can be used to determine the degree of neuronal maturation. Neuronal cytoskeletal proteins dictate the shape and structure of neurons, while synaptic plasticity and signaling processes are intricately associated with neuronal synaptic markers. Furthermore, abnormal expression levels of biomarkers can serve as diagnostic indicators for nervous system diseases. This article reviews the markers of mature neuronal differentiation and their relationship with nervous system diseases.

Intranasal delivery of Salmonella OMVs decorated with Chlamydia trachomatis antigens induces specific local and systemic immune responses

Chlamydia trachomatis is an obligate intracellular pathogen responsible for the most prevalent bacterial sexually transmitted disease globally. The high prevalence of chlamydial infections underscores the urgent need for licensed and effective vaccines to prevent transmission in populations. Bacterial outer membrane vesicles (OMVs) have emerged as promising mucosal vaccine carriers due to their inherent adjuvant properties and the ability to display heterologous antigens. In this proof-of-concept study, we evaluated the immunogenicity of Salmonella OMVs decorated with C. trachomatis MOMP-derived CTH522 or HtrA antigens in mice. Following a prime-boost intranasal vaccination approach, two OMV-based C. trachomatis vaccines elicited significant humoral responses specific to the antigens in both systemic and vaginal compartments. Furthermore, we demonstrated strong antigen-specific IFN-γ and IL17a responses in splenocytes and cervical lymph node cells of vaccinated mice, indicating CD4+ Th1 and Th17 biased immune responses. Notably, the OMV-CTH522 vaccine also induced the production of spleen-derived CD8+ T cells expressing IFN-γ. In conclusion, these results highlight the potential of OMV-based C. trachomatis vaccines for successful use in future challenge studies and demonstrate the suitability of our modular OMV platform for intranasal vaccine applications.

Recent progress in mRNA cancer vaccines

The research and development of messenger RNA (mRNA) cancer vaccines have gradually overcome numerous challenges through the application of personalized cancer antigens, structural optimization of mRNA, and the development of alternative RNA-based vectors and efficient targeted delivery vectors. Clinical trials are currently underway for various cancer vaccines that encode tumor-associated antigens (TAAs), tumor-specific antigens (TSAs), or immunomodulators. In this paper, we summarize the optimization of mRNA and the emergence of RNA-based expression vectors in cancer vaccines. We begin by reviewing the advancement and utilization of state-of-the-art targeted lipid nanoparticles (LNPs), followed by presenting the primary classifications and clinical applications of mRNA cancer vaccines. Collectively, mRNA vaccines are emerging as a central focus in cancer immunotherapy, offering the potential to address multiple challenges in cancer treatment, either as standalone therapies or in combination with current cancer treatments.

Research hotspots and trends regarding microRNAs in hypertension: a bibliometric analysis

To investigate the research levels, hotspots, and development trends regarding microRNAs in hypertension, this study conducted a visual analysis of studies on miRNA in hypertension based on the Web of Science core collection database using CiteSpace and VOSviewer analysis software along with literature from 2005-2023 as information data. Using citation frequency, centrality, and starting year as metrics, this study analyzed the research objects. It revealed the main research bodies and hotspots and evaluated the sources of literature and the distribution of knowledge from journals and authors. Finally, the potential research directions for miRNAs in hypertension are discussed. The results showed that the research field is in a period of vigorous development, and scholars worldwide have shown strong interest in this research field. A comprehensive summary and analysis of the current research status and application trends will prove beneficial for the advancement of this field.

The interplay between the tumor microenvironment and tumor-derived small extracellular vesicles in cancer development and therapeutic response

The tumor microenvironment (TME) plays an essential role in tumor cell survival by profoundly influencing their proliferation, metastasis, immune evasion, and resistance to treatment. Extracellular vesicles (EVs) are small particles released by all cell types and often reflect the state of their parental cells and modulate other cells' functions through the various cargo they transport. Tumor-derived small EVs (TDSEVs) can transport specific proteins, nucleic acids and lipids tailored to propagate tumor signals and establish a favorable TME. Thus, the TME's biological characteristics can affect TDSEV heterogeneity, and this interplay can amplify tumor growth, dissemination, and resistance to therapy. This review discusses the interplay between TME and TDSEVs based on their biological characteristics and summarizes strategies for targeting cancer cells. Additionally, it reviews the current issues and challenges in this field to offer fresh insights into comprehending tumor development mechanisms and exploring innovative clinical applications.

Exploring the dichotomy of the mesenchymal stem cell secretome: Implications for tumor modulation via cell-signaling pathways

Current cancer therapeutic strategies for the treatment of cancer are often unsuccessful due to unwanted side effects and drug resistance. Therefore, the design and development of potent, new anticancer platforms, such as stem-cell treatments, have attracted much attention. Distinctive biological properties of stem cells include their capacity to secrete bioactive factors, their limited immunogenicity, and their capacity for renewing themselves. Mesenchymal stem cells (MSCs) are one of several kinds of stem cells that are conveniently extracted and are able to be cultivated in vitro utilizing various sources. The secretome of stem cells contains many trophic factors, including cytokines, chemokines, growth factors, and microRNA molecules that can either promote or inhibit the formation of tumors, based on the cell environment. In the current review, we focused on the secretome of mesenchymal stem cells. These stem cells act as a double-edged sword in the regulation of cell signal transduction pathways in that they can either suppress or promote tumors.

Perspectives on the extracellular matrix in inflammatory bowel disease and bowel decellularization protocols

The extracellular matrix (ECM) is a non-cellular three-dimensional structure present in all tissues that is essential for the intestinal maintenance, function and structure, as well as for providing physical support for tissue integrity and elasticity. ECM enables the regulation of various processes involved in tissue homeostasis, being vital for healing, growth, migration and cell differentiation. Structurally, ECM is composed of water, polysaccharides and proteins, such as collagen fibers and proteoglycans, which are specifically arranged for each tissue. In pathological scenarios, such as inflammatory bowel disease (IBD), the deposition and remodeling of the ECM can be altered in relation to the homeostatic composition. IBD, such as Ulcerative colitis and Crohn’s disease, can be differentiated according to ECM alterations, such as circulating levels of collagen, laminin and vimentin neoepitopes. In this context, ECM presents particularities in both physiological and pathological processes, however, exploring methods of tissue decellularization is emerging as a promising frontier for new therapeutic interventions and clinical protocols, promoting the development of new approaches to intestinal diseases.

Catalase-positive Staphylococcus epidermidis based cryo-millineedle platform facilitates the photo-immunotherapy against colorectal cancer via hypoxia improvement

The synergistic anti-tumor impact of phototherapy and a cascading immune response are profoundly limited by hypoxia and a weakened immune response. Intravenous and intratumoral injection of therapeutic drugs also cause pain, rapid drug clearance and low utilization rates. Here, a novel cryo-millineedle platform for intratumoral delivery of a phototherapy system, S.epi@IR820, is developed in this work, combining the properties of Staphylococcus epidermidis (S. epidermidis) and IR820 for photo-immunotherapy of colorectal cancer. In this cryo-millineedle platform, S. epidermidis enhances the near-infrared absorption and light stability of IR820 and catalyzes the decomposition of H2O2 into O2 via an endogenous catalase to relieve tumor hypoxia, improve phototherapy and enhance immunogenic cell death (ICD). More interestingly, the native immunogenicity of S. epidermidis and ICD elicited by phototherapy achieved a potent anti-tumor immune response. To the best of our knowledge, this is the first study to utilize native S. epidermidis to relieve hypoxia and facilitate phototherapy. Both in vitro and in vivo experiments showed that the millineedle based phototherapy system can efficiently catalyse the decomposition of H2O2 into O2, facilitate phototherapeutic killing of CT26 tumor cells by S.epi@IR820 and enhance ICD, thus successfully activated the immune response and achieved the photo-immunotherapy against colorectal cancer. In conclusion, this study provides a novel strategy for enhanced anti-tumor efficiency of photo-immunotherapy, and develops an effective method for orthotopic administration of tumors.

Correlation between serum levels of circ_0001879 and circ_0004104, coronary microcirculation disorders and prognosis after percutaneous coronary intervention (PCI) in patients with stable coronary heart disease

OBJECTIVE

This study aims to elucidate the association between serum levels of circular RNAs circ_0001879 and circ_0004104 and the occurrence of coronary microcirculation disorders along with post-PCI prognosis in individuals with stable coronary heart disease.

METHODS

A cohort of 92 patients diagnosed with stable coronary heart disease and subjected to PCI between June 2020 and June 2022 at our institution was assembled. Patients were categorized into an exposed group (n = 60) and a non-exposed group (n = 32), predicated on the coronary angiography-derived microcirculation resistance index (caIMR).

RESULTS

Comparative analysis revealed significantly elevated levels of circ_0001879 and circ_0004104 in the serum of the exposed group compared to the non-exposed group, with statistical significance (P < 0.05). Post-PCI, both caFFR and caIMR values demonstrated a marked increase in comparison to pre-surgical measurements within both groups, with the exposed group exhibiting lower indices post-surgery relative to the non-exposed group, indicative of superior microcirculatory outcomes (P < 0.05). Furthermore, serum levels of circ_0001879 and circ_0004104 were inversely correlated with favorable prognosis, with lower levels observed in patients with positive outcomes (P < 0.05). The predictive accuracy for poor prognosis, as indicated by the area under the curve (AUC), was enhanced when circ_0001879 and circ_0004104 were considered in tandem (AUC = 0.934), surpassing the predictive power of individual assessments (Z combination vs circ_0001879 = 2.439, Z combination vs circ_0004104 = 2.317, P < 0.05).

CONCLUSION

Elevated serum levels of circ_0001879 and circ_0004104 are observed in stable coronary heart disease patients and are significantly associated with the presence of coronary microcirculation disorders and post-PCI prognosis, underscoring their potential as prognostic biomarkers.

Thermosensitive injectable fibrillar gels based on cellulose nanocrystals grafted with poly(N-isopropylacrylamide) as biocompatible brain implants

Drug treatment of glioblastoma, the most aggressive and widespread form of brain cancer, is complicated due to the difficulty of penetration of chemotherapeutic drugs through the blood-brain barrier (BBB). Moreover, with surgical removal of tumors, in 90 % of cases they reappear near the original focus. To solve this problem, we propose to use hydrogel based on cellulose nanocrystals grafted with poly(N-isopropylacrylamide) (CNC-g-PNIPAM) as a promising material for filling postoperative cavities in the brain with the release of antitumor drugs. The CNC-g-PNIPAM is formed by "grafting to" method for precise control of molecular weight and grafting density. This colloidal system is liquid under injection conditions (at r. t.) and turns into a gel at human body temperature (when filling the postoperative area). It was shown for the first time that due to the rod-shaped of CNC, the gel has a fibrillar structure and, thus, mechanical properties similar to those of brain tissue, including nonlinear mechanics (strain-stiffening and compression softening). The biocompatibility of the hydrogel with primary brain cells is demonstrated. In addition, the release of the antitumor drug paclitaxel from the hydrogel and its antitumor activity is shown. The resulting nanocolloid system provides an innovative alternative approach to filling postoperative cavities and can be used for postoperative treatment due to the programmable release of drugs, as well as for in vitro modeling of tumor interaction with the BBB affecting drug transport in the brain.

Raman microscopy allows to follow internalization, subcellular accumulation and fate of iron oxide nanoparticles in cells

An important issue in the context of both potenial toxicity of iron oxide nanoparticles (IONP) and their medical applications is tracking of the internalization process of these nanomaterials into living cells, as well as their localization and fate within them. The typical methods used for this purpose are transmission electron microscopy, confocal fluorescence microscopy as well as light-scattering techniques including dark-field microscopy and flow cytometry. All the techniques mentioned have their advantages and disadvantages. Among the problems it is necessary to mention complicated sample preparation, difficult interpretation of experimental data requiring qualified and experienced personnel, different behavior of fluorescently labeled IONP comparing to those label-free or finally the lack of possibility of chemical composition characteristics of nanomaterials. The purpose of the present investigation was the assessment of the usefulness of Raman microscopy for the tracking of the internalization of IONP into cells, as well as the optimization of this process. Moreover, the study focused on identification of the potential differences in the cellular fate of superparamagnetic nanoparticles having magnetite and maghemite core. The Raman spectra of U87MG cells which internalized IONP presented additional bands which position depended on the used laser wavelength. They occurred at the wavenumber range 1700-2400 cm-1 for laser 488 nm and below the wavenumber of 800 cm-1 in case of laser 532 nm. The intensity of the mentioned Raman bands was higher for the green laser (532 nm) and their position, was independent and not characteristic on the primary core material of IONP (magnetite, maghemite). The obtained results showed that Raman microscopy is an excellent, non-destructive and objective technique that allows monitoring the process of internalization of IONP into cells and visualizing such nanoparticles and/or their metabolism products within them at low exposure levels. What is more, the process of tracking IONP using the technique may be further improved by using appropriate wavelength and power of the laser source.

A coumarin-naphthalimide-based ratiometric fluorescent probe for nitroxyl (HNO) based on an ICT-FRET mechanism

Nitroxyl (HNO) is an important reactive nitrogen that is associated with various states in physiology and pathology and plays a unique function in living systems. So, it is important to exploit fluorescent probes with high sensitivity and selectivity for sensing HNO. In this paper, a novel ratiometric fluorescent probe for HNO was developed utilizing intramolecular charge transfer (ICT) and fluorescence resonance energy transfer (FRET) mechanisms. The probe selected coumarin as energy donor, naphthalimide as energy receptor and 2-(diphenylphosphino)benzoate as the sensing site for detecting HNO. When HNO was not present, the 2-(diphenylphosphino)benzoate unit of the probe restricted electron transfer and the ICT process could not occur, leading to the inhibition of FRET process as well. Thus, in the absence of HNO the probe displayed the intrinsic blue fluorescence of coumarin. When HNO was added, the HNO reacted with the 2-(diphenylphosphino)benzoate unit of the probe to yield a hydroxyl group which resulting in the opening of ICT process and the occurring of FRET process. Thus, after providing HNO the probe displayed yellow fluorescence. In addition, the probe showed good linearity in the ratio of fluorescence intensity at 545 nm and 472 nm (I545 nm/I472 nm) with a concentration of HNO (0.1-20 μM). The probe processed a detection limit of 0.014 μM and a response time of 4 min. The probe also specifically identified HNO over a wide pH scope (pH = 4.00-10.00), including physiological conditions. Cellular experiments had shown that this fluorescent probe was virtually non-cytotoxic and could be applied for ratiometric sensing of HNO in A549 cells.

Spatiotemporal dynamics of microscopic biological barrier visualized by electric-double-layer modulation imaging

Live-cell label-free imaging of a microscopic biological barrier, generally referred to as 'tight junction', was realized by a recently developed electric-double-layer modulation imaging (EDLMI). The method allowed quantitative imaging of barrier integrity in real time, thus being an upper compatible of transepithelial electrical resistance (TEER) which is a conventional standard technique to evaluate spatially averaged barrier integrity. We demonstrate that the quantitative and real-time imaging capability of EDLMI unveils fundamental dynamics of biological barrier, some of which are totally different from conventional understandings.

Sodium butyrate improves cognitive dysfunction in high-fat diet/ streptozotocin-induced type 2 diabetic mice by ameliorating hippocampal mitochondrial damage through regulating AMPK/PGC-1α pathway

Cognitive dysfunction is an important comorbidity of type 2 diabetes mellitus (T2DM). Sodium butyrate (NaB) is a short-chain fatty acid and has an effect improving T2DM-associated cognitive dysfunction. Using a high-fat diet (HFD)/streptozotocin (STZ)-induced T2DM mouse model, the present study investigated the mechanism involved in the beneficial effect of butyrate on diabetic cognitive dysfunction, with a focus on ameliorating mitochondrial damage through regulating the adenosine monophosphate-activated protein kinase/peroxisome proliferator-activated receptor gamma coactivator 1α (AMPK/PGC-1α) pathway considering the important role of mitochondrial impairments in the occurrence of T2DM-associated cognitive dysfunction. We found, based on reconfirmation of the improvement of NaB on cognitive impairment, that NaB treatment improved damaged synaptic structural plasticity including the decrease in dendritic spine density and downregulation in the expression of postsynaptic density protein 95 and synaptophysin in the hippocampus in the model mice. NaB treatment also ameliorated mitochondrial ultrastructural damage, increased mitochondrial membrane potential and adenosine 5'-triphosphate content, and improved mitochondrial biogenesis and dynamics in the model mice. Furthermore, the expression of phosphorylated AMPK and PGC-1α was upregulated after NaB treatment in the model mice. In particular, the above beneficial effects of NaB were blocked by the inhibition of either AMPK or PGC-1α. In conclusion, NaB treatment improved cognitive impairment and damaged synaptic structural plasticity in the hippocampus by ameliorating damage to mitochondrial morphology and function through regulating the AMPK/PGC-1α pathway in HFD/STZ-induced T2DM mice.

Chitosan/dextran-based organohydrogel delivers EZH2 inhibitor to epigenetically reprogram chemo/immuno-resistance in unresectable metastatic melanoma

Melanoma either intrinsically possesses resistance or rapidly acquires resistance to anti-tumor therapy, which often leads to local recurrence or distant metastasis after resection. In this study, we found histone 3 lysine 27 (H3K27) demethylated by an inhibitor of histone methyltransferase EZH2 could epigenetically reverse the resistance to chemo-drug paclitaxel (PTX), or enhance the efficacy of immune checkpoint inhibitor anti-TIGIT via downregulating TIGIT ligand CD155. Next, to address the complexity in the combination of multiple bioactive molecules with distinct therapeutic properties, we developed a polysaccharides-based organohydrogel (OHG) configured with a heterogenous network. Therein, hydroxypropyl chitosan (HPC)-stabilized emulsions for hydrophobic drug entrapment were crosslinked with oxidized dextran (Odex) to form a hydrophilic gel matrix to facilitate antibody accommodation, which demonstrated a tunable sustained release profile by optimizing emulsion/gel volume ratios. As results, local injection of OHG loaded with EZH2 inhibitor UNC1999, PTX and anti-TIGIT did not only synergistically enhance the cytotoxicity of PTX, but also reprogrammed the immune resistance via bi-directionally blocking TIGIT/CD155 axis, leading to the recruitment of cytotoxic effector cells into tumor and conferring a systemic immune memory to prevent lung metastasis. Hence, this polysaccharides-based OHG represents a potential in-situ epigenetic-, chemo- and immunotherapy platform to treat unresectable metastatic melanoma.

Berberine-doped montmorillonite nanosheet for photoenhanced antibacterial therapy and wound healing

Bacterial infections pose a substantial threat to human health, particularly with the emergence of antibiotic-resistant strains. Therefore, it is essential to develop novel approaches for the efficient treatment of bacterial diseases. This study presents a therapeutic approach involving BBR@MMT nanosheets (NSs), wherein montmorillonite (MMT) was loaded with berberine (BBR) through an ion intercalation reaction to sterilize and promote wound healing. BBR@MMT exhibits nano-enzymatic-like catalytic activity, is easy to synthesize, and requires low reaction conditions. This nanocomplex showed photodynamic properties and superoxide dismutase (SOD) activity. The in vitro experiments indicated that BBR@MMT was able to effectively inhibit the growth of Gram-positive bacteria (S. aureus) and Gram-negative bacteria (E. coli) through the production of ROS when exposed to white light. Meanwhile, BBR@MMT inhibited the secretion of pro-inflammatory factors and scavenged free radicals via its SOD-like activity. In vivo results showed that BBR@MMT NSs were capable of effectively promoting the wound-healing process in infected mice under white light irradiation. Hence, it can be concluded that photodynamic therapy based on BBR@MMT NSs with nano-enzymatic activity has the potential to be used in treating infections and tissue repair associated with drug-resistant microorganisms.

Aggregation-induced emission: Application in diagnosis and therapy of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a serious health issue due to its low early diagnosis rate, resistance to chemotherapy, and poor five-year survival rate. Therefore, it is crucial to explore novel diagnostic and therapeutic approaches tailored to the characteristics of HCC. Aggregation-induced emission (AIE) is a phenomenon where the luminescence of certain molecules, typically non-luminescent or weakly luminescent in solution, is significantly enhanced upon aggregation. AIE has been extensively applied in bioimaging, biosensors, and therapy. Fluorophore materials based on AIE (AIEgens) have a wide range of application scenarios and potential for clinical translation. This review focuses on recent advances in AIE-based strategies for diagnosing and treating HCC. First, the specific functional mechanism of AIE is described. Next, we summarize recent progress in the application of AIE for multimodal imaging, biosensor detection, and phototherapy. Finally, prospects and challenges for the AIE-based application in the diagnosis and therapy of HCC are discussed.

Nanofiber-boosted retrograded starch/pectin microparticles for targeted 5-Aminosalicylic acid delivery in inflammatory bowel disease: In vitro and in vivo non-toxicity evaluation

Incorporating 5-aminosalicylic acid (5-ASA) into a colon-specific carrier is crucial for treating inflammatory bowel diseases (IBD), as it enhances therapeutic efficacy, targets the affected regions directly, and minimizes side effects. This study evaluated the impact of incorporating cellulose nanofibers (CNF) on the in vitro and in vivo biological performance of retrograded starch/pectin (RS/P) microparticles (MPs) containing 5-ASA. Using Fourier Transform Infrared (FTIR) Spectroscopy, shifts in the spectra of retrograded samples containing CNF were observed with increasing CNF proportions, suggesting the establishment of new supramolecular interactions. Liquid absorption exhibited pH-dependent behaviors, with reduced absorption in simulated gastric fluid (∼269 %) and increased absorption in simulated colonic fluid (∼662 %). Increasing CNF concentrations enhanced mucoadhesion in porcine colonic sections, with a maximum force of 3.4 N at 50 % CNF. Caco-2 cell viability tests showed biocompatibility across all tested concentrations (0.0625-2.0000 mg/mL). Evaluation of intestinal permeability in Caco-2 cell monolayers demonstrated up to a tenfold increase in 5-ASA permeation, ranging from 29 % to 48 %. An in vivo study using Galleria mellonella larvae, with inflammation induced by LPS, showed reduction of inflammation. Given the scalability of spray-drying, these findings suggest the potential of CNF-incorporated RS/P microparticles for targeted 5-ASA delivery in IBD.

Smart nanozymes coupled with dynamic magnet field and laser exposures for cancer therapy

Developing nanozymes for cancer therapy has attracted great attention from researchers. However, enzymes-loaded magnetic particles triggered by both a low-frequency vibrating magnetic field (VMF) and laser for inhibiting tumor growth have never been reported. Herein, we developed a magnetic nanozyme with 3D flower-like nanostructures for cancer therapy. Specifically, the flower-like nanozymes exposed to a VMF could efficiently damage the mitochondrial membrane and cell structure, and inhibit tumor growth through magneto-mechanical force. In parallel, magnetic nanozymes in a weak acid environment containing glucose could generate abundant hydrogen peroxide through glucose oxidase-catalyzed oxidation of glucose, and further significantly promote the Fenton reaction. Interestingly, both glucose oxidase- and Fenton-based catalytic reactions were significantly promoted by the VMF exposure. Flower-like magnetic nanospheres upon a near-infrared laser irradiation could also damage cancer cells and tumor tissues through photothermal effect. The cell-killing efficiency of magnetic nanozymes triggered by the VMF or laser significantly increased in comparison with that of nanozymes without exposures. Mouse tumors grown after injection with magnetic nanozymes was inhibited in a significant way or the tumors disappeared after exposure to a VMF and laser due to the synergistic effect of four major stimuli, viz., magneto-mechanical force, photothermal conversion, improved Fenton reaction, and intratumoral glucose consumption-based starvation effect. This is a great platform that may be suitable for treating many solid tumors.

Enhancing tumor endothelial permeability using MUC18-targeted gold nanorods and mild hyperthermia

The Enhanced Permeability and Retention (EPR) effect, an elevated accumulation of drugs and nanoparticles in tumors versus in normal tissues, is a widely used concept in the field of cancer therapy. It assumes that the vasculature of solid tumors would possess abnormal, leaky endothelial cell barriers, allowing easy access of intravenous-delivered drugs and nanoparticles to tumor regions. However, the EPR effect is not always effective owing to the heterogeneity of tumor endothelium over time, location, and species. Herein, we introduce a unique nanoparticle-based approach, using MUC18-targeted gold nanorods coupled with mild hyperthermia, to specifically enhance tumor endothelial permeability. This improves the efficacy of traditional cancer therapy including photothermal therapy and anticancer drug delivery by increasing the transport of photo-absorbers and drugs across the tumor endothelium. Using single cell imaging tools and classic analytical approaches in molecular biology, we demonstrate that MUC18-targeted gold nanorods and mild hyperthermia enlarge the intercellular gaps of tumor endothelium by inducing circumferential actin remodeling, stress fiber formation, and cell contraction of adjacent endothelial cells. Considering MUC18 is overexpressed on a variety of tumor endothelium and cancer cells, this approach paves a new avenue to improve the efficacy of cancer therapy by actively enhancing the tumor endothelial permeability.

Molecular weight-mediated interaction changes for enhancing structural stability, release behavior and M cells-targeting transport efficacy of starch-based nanoparticles

Molecular weight (Mw) of ligand-mediated nanocarriers plays a pivotal role in their architecture and properties. In this study, self-assembled ovalbumin (OVA)-loaded nanoparticles were meticulously engineered by starch polyelectrolytes with different Mw. Results unveiled that, tailoring Mw of GRGDS pentapeptides-grafted carboxymethyl starch (G-CMS) displayed strong binding-affinity and transport efficiency through microfold cells (M cells) pathway in the simulated intestinal epithelial cell monolayer in which M cells were randomly located in the Caco-2 cells monolayer. Notably, nanoparticles assembled from G-CMS with relatively higher Mw exhibited more compact structures due to the stronger interactions between layers compared to that with relatively lower Mw, which rendered remarkably stable and only 19.01 % in vitro OVA leakage under conditions of the upper gastrointestinal tract. Subsequently, more intact nanoparticles reached M cells after in vitro digestion and exhibited higher transport efficiency through the M cells pathways (apparent permeability: 9.38 × 10-5 cm/s) than Caco-2 cells, attributing to specific- and non-specific binding affinity towards M cells. Therefore, optimal Mw tailoring of starch polyelectrolytes can mediate the molecular interactions among their assembled layers and the interactions with M cells to balance the structural compactness, release and transport efficacy of nanoparticles, holding promise for advancing M cells-targeting oral delivery technologies.

Identification of a novel neutralization epitope in rhesus AAVs

Adeno-associated viruses (AAVs) are popular gene therapy delivery vectors, but their application can be limited by anti-vector immunity. Both preexisting neutralizing antibodies (NAbs) and post-administration NAbs can limit transgene expression and reduce the clinical utility of AAVs. The development of novel AAVs will advance our understanding of AAV immunity and may also have practical applications. In this study, we identified five novel AAV capsids from rhesus macaques. RhAAV4282 exhibited 91.4% capsid sequence similarity with AAV7 and showed similar tissue tropism with slightly diminished overall signal. Despite this sequence homology, RhAAV4282 and AAV7 showed limited cross-neutralization. We determined a cryo-EM structure of the RhAAV4282 capsid at 2.57 Å resolution and identified a small segment within the hypervariable region IV, involving seven amino acids that formed a shortened external loop in RhAAV4282 compared with AAV7. We generated RhAAV4282 and AAV7 mutants that involved swaps of this region and showed that this region partially determined neutralization phenotype. We termed this region the hypervariable region IV neutralizing epitope (HRNE). Our data suggests that modification of the HRNE can lead to AAVs with altered neutralization profiles.

l-Type amino acid transporter 1-targeting nanoparticles for antisense oligonucleotide delivery to the CNS

l-Type amino acid transporter 1 (LAT1)-specific ligands and polyion complexes are used as brain-specific targets to deliver RNA-based drugs across the blood-brain barrier. We characterized an LAT1-targeting antisense oligonucleotide (ASO)-encapsulated nanoparticle, Phe-NPs/ASO. A 25% density of phenylalanine effectively binds to the surface of LAT1-targeting NPs in the GL261-Luc cells, and Phe-NPs/ASO shows higher binding affinity compared to that without phenylalanine by cellular binding assay. To further characterize the blood-brain barrier-targeting effect and tissue distribution following a single-dose intravenous injection in mice, we performed in vivo biodistribution studies using fluorescence imaging. The Phe-NPs/ASOs were detected in the brain tissue 1 h post-intravenous injection at an approximately 64-fold higher ratio than that of the same ASOs administered in the absence of any NP carrier. The brain tissue delivery of ASO-loaded Phe-NPs was also confirmed in a fluorescence imaging study performed in non-human primates. These results demonstrate that Phe-NPs may successfully deliver an ASO to the brain tissue across brain regions. Phe-NPs loaded with RNA-based drugs have the potential to treat diseases of the CNS, including all forms of neurodegenerative diseases.

Optimization of a lentivirus-mediated gene therapy targeting HIV-1 RNA to eliminate HIV-1-infected cells

Persistence of HIV-1 in cellular reservoirs results in lifelong infection, with cure achieved only in rare cases through ablation of marrow-derived cells. We report on optimization of an approach that could potentially be aimed at eliminating these reservoirs, hijacking the HIV-1 alternative splicing process to functionalize the herpes simplex virus thymidine kinase (HSVtk)/ganciclovir (GCV) cell suicide system through targeted RNA trans-splicing at the HIV-1 D4 donor site. AUG1-deficient HSVtk therapeutic pre-mRNA was designed to gain an in-frame start codon from HIV-1 tat1. D4-targeting lentiviral vectors were produced and used to transduce HIV-1-expressing cells, where trans-spliced HIV-1 tat/HSVtk mRNA was successfully detected. However, translation of catalytically active HSVtk polypeptides from internal AUGs in HSVtk ΔAUG1 caused GCV-mediated cytotoxicity in uninfected cells. Modifying these sites in the D4 opt 2 lentiviral vector effectively mitigated this major off-target effect. Promoter choice was optimized for increased transgene expression. Affinity for HIV-1 RNA predicted in silico correlated with the propensity of opt 2 payloads to induce HIV-1 RNA trans-splicing and killing of HIV-1-expressing cells with no significant effect on uninfected cells. Following latency reversing agent (LRA) optimization and treatment, 45% of lymphocytes in an HIV-1-infected latency model could be eliminated with D4 opt 2/GCV. Further development would be warranted to exploit this approach.

Targeting ocular tissues with intravenously administered aptamers selected by in vivo SELEX

Ocular diseases create a significant economic burden and decrease in quality of life worldwide. Drugs and carrier molecules that penetrate ocular tissues after intravenous administration are needed for more efficient and patient-friendly treatment of ocular diseases. Here, ocular barrier-penetrating aptamers were selected through the utilization of in vivo SELEX and intravenous injection in rats. Three aptamers-Apt1, Apt2, and Apt5-were chosen based on their specific accumulation in vascularized ocular tissues and further characterized for their in vivo biodistribution using quantitative reverse-transcription PCR (RT-qPCR). A statistically significant difference between ΔCt values of ocular and control tissues with Apt2 (p < 0.0001) and Apt5 (p < 0.0001) was observed. Interestingly, Apt1 was the most abundant aptamer in the sequencing pool, but it did not show a statistically significant difference in in vivo biodistribution between ocular and control tissues. Overall, this study established a functional in vivo SELEX method for discovering ocular tissue targeting aptamers.

Inhibition of SARS-CoV-2 growth in the lungs of mice by a peptide-conjugated morpholino oligomer targeting viral RNA

Further development of direct-acting antiviral agents against human SARS-CoV-2 infections remains a public health priority. Here, we report that an antisense peptide-conjugated morpholino oligomer (PPMO) named 5'END-2, targeting a highly conserved sequence in the 5' UTR of SARS-CoV-2 genomic RNA, potently suppressed SARS-CoV-2 growth in vitro and in vivo. In HeLa-ACE 2 cells, 5'END-2 produced IC50 values of between 40 nM and 1.15 μM in challenges using six genetically disparate strains of SARS-CoV-2, including JN.1. In vivo, using K18-hACE2 mice and the WA-1/2020 virus isolate, two doses of 5'END-2 at 10 mg/kg, administered intranasally on the day before and the day after infection, produced approximately 1.4 log10 virus titer reduction in lung tissue at 3 days post-infection. Under a similar dosing schedule, intratracheal administration of 1.0-2.0 mg/kg 5'END-2 produced over 3.5 log10 virus growth suppression in mouse lungs. Electrophoretic mobility shift assays characterized specific binding of 5'END-2 to its complementary target RNA. Furthermore, using reporter constructs containing SARS-CoV-2 5' UTR leader sequence, in an in-cell system, we observed that 5'END-2 could interfere with translation in a sequence-specific manner. The results demonstrate that direct pulmonary delivery of 5'END-2 PPMO is a promising antiviral strategy against SARS-CoV-2 infections and warrants further development.

Sanqi oral solution ameliorates renal fibrosis by suppressing fibroblast activation via HIF-1α/PKM2/glycolysis pathway in chronic kidney disease

ETHNOPHARMACOLOGICAL RELEVANCE

Sanqi oral solution (SQ) is a traditional Chinese patent medicine, widely used to treat chronic kidney diseases (CKD) in the clinic in China. Previous studies have confirmed its anti-renal fibrosis effect, but the specific pharmacological mechanism is still unclear.

AIM OF THE STUDY

Focusing on energy metabolism in fibroblasts, the renoprotective mechanism of SQ was investigated in vitro and in vivo.

METHODS

Firstly, the fingerprint of SQ was constructed and its elementary chemical composition was analyzed. In the 5/6Nx rats experiment, the efficacy of SQ on the kidney was evaluated by detecting serum and urine biochemical indexes and pathological staining of renal tissues. Lactic acid and pyruvic acid levels in serum and renal tissues were detected. PCNA protein expression in kidney tissue was detected by immunofluorescence assay and Western blot. Expression levels of HIF-1α, PKM2 and HK2 were determined by immunohistochemistry, Western blot or RT-qPCR assay. In addition, the effect of SQ intervention on cell proliferation and glycolysis was evaluated in TGF-β1-induced NRK-49F cells, and the role of SQ exposure and HIF-1α/PKM2/glycolysis pathway were further investigated by silencing and overexpressing HIF-1α gene in NRK-49F cells.

RESULTS

In 5/6 Nx rats, SQ effectively improved renal function and treated renal injury. It reduced the levels of lactic acid and pyruvic acid in kidney homogenates from CKD rats and decreased the expression levels of HIF-1α, PKM2, HK2, α-SMA, vimentin, collagen I and PCNA in kidney tissues. Similar results were observed in vitro. SQ inhibited NRK-49F cell proliferation, glycolysis and the expression levels of HIF-1α, PKM2 induced by TGF-β1. Furthermore, we established NRK-49F cells transfected with siRNA or pDNA to silence or overexpress the HIF-1α gene. Overexpression of HIF-1α promoted cellular secretion of lactic acid and pyruvic acid in TGF-β1-induced NRK-49F cells, however, this change was reversed by intervention with SQ or silencing the HIF-1α gene. Overexpression of HIF-1α can further induce increased PKM2 expression, while SQ intervention can reduce PKM2 expression. Moreover, PKM2 expression was also inhibited after silencing HIF-1α gene, and SQ was not effective even when given.

CONCLUSION

The mechanism of action of SQ was explored from the perspective of energy metabolism, and it was found to regulate PKM2-activated glycolysis, inhibit fibroblast activation, and further ameliorate renal fibrosis in CKD by targeting HIF-1α.

Current status of nucleic acid therapy and its new progress in cancer treatment

Nucleic acid is an essential biopolymer in all living cells, performing the functions of storing and transmitting genetic information and synthesizing protein. In recent decades, with the progress of science and biotechnology and the continuous exploration of the functions performed by nucleic acid, more and more studies have confirmed that nucleic acid therapy for living organisms has great medical therapeutic potential. Nucleic acid drugs began to become independent therapeutic agents. As a new therapeutic method, nucleic acid therapy plays an important role in the treatment of genetic diseases, viral infections and cancers. There are currently 19 nucleic acid drugs approved by the Food and Drug Administration (FDA). In the following review, we start from principles and advantages of nucleic acid therapy, and briefly describe development history of nucleic acid drugs. And then we give examples of various RNA therapeutic drugs, including antisense oligonucleotides (ASO), mRNA vaccines, small interfering RNA (siRNA) and microRNA (miRNA), aptamers, and small activating RNA (saRNA). In addition, we also focused on the current status of nucleic acid drugs used in cancer therapy and the breakthrough in recent years. Clinical trials of nucleic acid drugs for cancer treatment are under way, conventional radiotherapy and chemotherapy combined with the immunotherapies such as checkpoint inhibitors and nucleic acid drugs may be the main prospects for successful cancer treatment.

Current status of nanoparticle-mediated immunogenic cell death in cancer immunotherapy

Immunogenic cell death (ICD) encompasses various forms of cell death modalities, including apoptosis, necroptosis, ferroptosis, and pyroptosis. It arises from a harmonious interplay of adjuvant (damage-associated molecular patterns-DAMPs and chemokines/cytokines) and antigenicity (tumor-associated antigens-TAA) to induce immune-reaction toward cancer cells. Inducing ICD stands out as a promising approach in cancer immunotherapy, capable of directly eliminating cancer cells and of eliciting enduring antitumor immune responses. Conventional tumor therapies like radiation therapy, photodynamic therapy, and chemotherapy can also induce ICD which could amplify their activities. The development of effective ICD inducers like nano-systems is crucial for ensuring safe and efficacious immunotherapy. Nanoparticles hold considerable promise in cancer therapy, offering enhanced therapeutic outcomes and mitigated side effects. They could be the capacity to adjust systemic biodistribution, augment the accumulation of therapeutic agents at the intended site and protect active agents from the complexity of human biofluid. This review aims to outline the role of nanoparticles in triggering ICD for cancer immunotherapy that potentially pave the way for cancer treatment.

Design and synthesis of pyrano[2,3-c]pyrazole-4-aminoquinoline hybrids as effective antimalarial compounds

In this work, a series of nineteen novel pyrano[2,3-c]pyrazole-4-aminoquinoline hybrids were synthesized as potent antimalarial agents by covalently linking the scaffolds of 4-aminoquinoline and pyrano[2,3-c]pyrazoles via an ethyl linker and characterized using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR). Molecular docking was used to test each hybrid's and standard chloroquine's ability to bind to Plasmodium falciparum lactate dehydrogenase enzyme (PfLDH), an important enzyme in the parasite's glycolytic pathway. The hybrid compounds had a stronger binding affinity than the standard chloroquine (CQ). The schizontical antimalarial test of pyrano[2,3-c]pyrazole-4-aminoquinoline hybrid compound shows that all nineteen hybrid compounds were potent with the IC50 values ranging from 0.0151 to 0.301 μM against the CQ-sensitive 3D7 P. falciparum strain, and were active against the CQ-resistant K1 P. falciparum strain with the IC50 values ranging from 0.01895 to 2.746 μM. All the tested hybrid compounds were less potent than the standard drug chloroquine dipaspate (CQDP) against the CQ-sensitive 3D7 strain. In contrast, nine of the nineteen hybrids (16d, 16g, 16h, 16i, 16l, 16n, 16o, 16r, and 16s) displayed superior antimalarial activity than the CQDP against the CQ-resistant K1 P. falciparum strain. Among all the tested hybrids, 16c against the 3D7 strain and 16h against the K1 strain were the most promising antimalarial agents with 0.0151 and 0.01895 μM of IC50 values, respectively. In addition, the compounds were selective, showing moderate to low cytotoxic activity against a human normal liver WRL68 cell line. The synthesis of pyrano[2,3-c]pyrazole-4-aminoquinoline hybrids introduces new chemical entities that have the potential to exhibit potent antimalarial activity. It could address the ongoing challenge of drug resistance in malaria treatment.

Raman spectroscopic investigation of polymer based magnetic multicomponent scaffolds

Scaffolds acting as an artificial matrix for cell proliferation are one of the bone tissue engineering approaches to the treatment of bone tissue defects. In the presented study, novel multicomponent scaffolds composed of a poly(ε-caprolactone) (PCL), phenolic compounds such as tannic (TA) and gallic acids (GA), and nanocomponents such as silica-coated magnetic iron oxide nanoparticles (MNPs-c) and functionalized multi-walled carbon nanotubes (CNTs) have been produced as candidates for such artificial substitutes. Well-developed interconnected porous structures were observed using scanning electron microscopy (SEM). Raman spectra showed that the highly crystalline nature of PCL was reduced by the addition of nanoadditives. In the case of scaffolds containing MNPs-c and TA, the formation of a Fe-TA complex was concluded because characteristic bands of chelation of the Fe3+ ion by phenolic catechol oxygen appeared. It was found that the necessary conditions for the crystallization of the PCL/MNPs-c/TA are for the catechol groups to be able to penetrate the porous silica shell of MNPs-c, as during experiment with MNPs-c and TA without polymer, no such complexation was observed. Moreover, the number of catechol groups, the spatial structure and molecular size of this phenolic compound are also crucial for complexation process because GA does not form complexes. Therefore, the PCL/CNTs/MNPs-c/TA scaffolds are interesting candidates to consider for their possible medical applications.

MCC950 promotes diabetic wound healing through modulating macrophage polarization in an MDSC-dependent manner

Diabetic foot ulcers (DFUs) are serious skin injuries whereby the wound healing process is frequently stalled in the inflammatory phase. Currently, there is a lack of effective therapeutic strategies. MCC950, a highly selective nod-like receptor family pyrin domain containing 3 (NLRP3) inhibitor, has been reported to show strong anti-inflammation effects in many diseases. In this study, we unveiled the role of MCC950 in DFU mice model and its underlying molecular mechanisms. MCC950 could significantly accelerate diabetic wound healing, as shown by shortened healing time and better healing quality. Moreover, increased M2 phenotype macrophages and decreased pro-inflammatory genes were observed in MCC950-treated DFU mice. Additionally, myeloid-derived suppressor cells (MDSCs) were significantly increased in blood, spleen and wound tissues at different time courses. Specifically, MCC950 could recruit more MDSCs in an early phase in DFU mice, exerting an anti-inflammation effect. We identified the cell crosstalk between macrophages and MDSCs with MCC950 treatment process. Depleting MDSCs in vivo could eliminate the therapeutic effect of MCC950 on diabetic wound healing through inhibiting M2 macrophage polarization. Besides, MDSCs isolated from the wounds of MCC950 or saline treated mice were cocultured with bone marrow derived macrophage (BMDM) in a transwell system. Results confirmed that MDSCs sorted from MCC950 treated mice caused a significant increased percentage of M2 macrophages. Collectively, our findings suggest that the administration of MCC950 has the potential to accelerate diabetic wound healing by promoting M2 macrophage polarization in an MDSC-dependent manner. This study provides valuable insights into the utilization of pharmacological agents for DFU treatment.