High Immunogenicity Research Articles

Cancer Stem Cells and the Renin–Angiotensin System in the Tumor Microenvironment of Melanoma: Implications on Current Therapies

Multiple signaling pathways are dysregulated in melanoma, notably the Ras/RAF/MAPK/ERK and PI3K/AKT/mTOR pathways, which can be targeted therapeutically. The high immunogenicity of melanoma has been exploited using checkpoint inhibitors. Whilst targeted therapies and immune checkpoint inhibitors have improved the survival of patients with advanced melanoma, treatment resistance, their side effect profiles, and the prohibitive cost remain a challenge, and the survival outcomes remain suboptimal. Treatment resistance has been attributed to the presence of cancer stem cells (CSCs), a small subpopulation of pluripotent, highly tumorigenic cells proposed to drive cancer progression, recurrence, metastasis, and treatment resistance. CSCs reside within the tumor microenvironment (TME) regulated by the immune system, and the paracrine renin–angiotensin system, which is expressed in many cancer types, including melanoma. This narrative review discusses the role of CSCs and the paracrine renin–angiotensin system in the melanoma TME, and its implications on the current treatment of advanced melanoma with targeted therapy and immune checkpoint blockers. It also highlights the regulation of the Ras/RAF/MAPK/ERK and PI3K/AKT/mTOR pathways by the renin–angiotensin system via pro-renin receptors, and how this may relate to CSCs and treatment resistance, underscoring the potential for improving the efficacy of targeted therapy and immunotherapy by concurrently modulating the renin–angiotensin system.

Designing a broad-spectrum multi-epitope subunit vaccine against leptospirosis using immunoinformatics and structural approaches

IntroductionLeptospirosis, caused by Leptospira interrogans, is a neglected zoonotic disease that poses a significant global health risk to both humans and animals. The rise of antimicrobial resistance and the inefficacy of existing vaccines highlight the urgent need for new preventive strategies.MethodsAn immunoinformatics approach was employed to design a multi-epitope subunit vaccine (MESV) against leptospirosis. B-cell, cytotoxic T lymphocyte (CTL), and helper T lymphocyte (HTL) epitopes were selected from five key Leptospira proteins. These epitopes were fused with a heparin-binding hemagglutinin (HBHA) adjuvant and appropriate linkers to construct the broad-spectrum vaccine. The physicochemical properties of the vaccine were assessed, including antigenicity, immunogenicity, allergenicity, and conservation. The vaccine’s 3D structure was modeled, optimized, and validated. Molecular docking, molecular dynamics simulations, and MM-GBSA analysis were performed to assess the vaccine's binding interactions with Toll-like receptors (TLR2 and TLR4). Immune simulations and in silico cloning were also conducted to evaluate the vaccine’s immune response and expression potential.ResultsThe MESV demonstrated high antigenicity, immunogenicity, non-allergenicity, and conservation across different Leptospira strains. Population coverage analysis revealed that T-cell epitopes significantly interacted with HLA molecules, covering 95.7% of the global population. Molecular docking showed strong and stable binding with TLR2 and TLR4, with binding energies of -1,357.1 kJ/mol and -1,163.7 kJ/mol, respectively. Molecular dynamics simulations and MM-GBSA analysis confirmed the stability of these interactions and accurately calculated the intermolecular binding free energies. Immune simulations indicated robust B and T cell responses, and in silico cloning demonstrated that the vaccine could be successfully expressed in E. coli.DiscussionThese findings suggest that MESV is a promising candidate for leptospirosis prevention, providing robust immune responses and broad population coverage. However, further in vivo studies are necessary to validate its efficacy and safety.

Immune cells in thyroid adenoma and carcinoma: uncovering a hidden value of assessing tumor-host interplay and its potential application in thyroid cytopathology

IntroductionAlthough the role of tumor immune microenvironment (TIME) in thyroid cancer is well established, little data exists about the differences in immune cell presence in thyroid adenomas and carcinomas. We assume that immune cell density could be an additional diagnostic criterion for differentiating benign and malignant tumors in thyroid aspirates.AimThe current study compared the immune contexture of thyroid adenoma (TA) and thyroid carcinoma (TC) in histological and cytological specimens of III-V categories.Materials and methodsThis pilot study included 72 cases (36 of TA and 36 of TC) with verified histological diagnosis and pre-operative cytology corresponding to categories III, IV and V according to the Bethesda system for reporting thyroid cytology. The number of CD8+, CD68+ and CD163+ cells was assessed in histological samples of TA and TC with further comparison to cytological specimens. Besides, the expression of STAT6 and SMAD4 as potential regulators of TIME was evaluated in the study.ResultsTC demonstrated an immune-rich profile representing abundant tumor-associated CD8+ lymphocytes, CD68 and CD163+ macrophages. In contrast, TA represented mostly a low immune cell infiltration. The higher immunogenicity of TC was accompanied by the more profound expression of STAT6 and SMAD4 in tumor cells. The number of immune cells in cytological specimens correlated with CD8+ (r = 0.693; p < 0.001) and CD163+ cells (r = 0.559; p < 0.001) in histological samples, reflecting the differences in the tumor immune microenvironment between benign and malignant thyroid neoplasms.ConclusionTC demonstrated high immunogenicity compared to TA, which correlated to the number of immune cells in cytological specimens. The number of immune cells in thyroid cytology samples could be an additional criterion in cytological diagnostics for III-V Bethesda categories. Further investigations are needed to validate the findings of the study.

Macrophage Membrane-Encapsulated Carbon Dots for Precise Targeting Diagnosis and Treatment of Bacterial Infections.

How to accurately diagnose and treat bacterial infections in vivo remains a huge challenge. Therefore, we have developed a targeted delivery nanosystem by coextruding the pretreated macrophage membrane of S. aureus with carbon dots (M@CD). The M@CD nanosystem demonstrates potent antibacterial effects both in vivo and in vitro through the generation of reactive oxygen species (ROS). Furthermore, M@CD exhibits enhanced targeting ability and stable fluorescence properties, addressing issues such as poor targeting efficiency and high immunogenicity in vivo. This innovative approach enables infection site specific aggregation and elimination of bacterial infections, thereby providing a promising strategy for the integrated diagnosis, treatment, and monitoring of bacterial infections.

An OMV-Based Nanovaccine as Antigen Presentation Signal Enhancer for Cancer Immunotherapy.

Antigen-presenting cells (APCs) process tumor vaccines and present tumor antigens as the first signals to T cells to activate anti-tumor immunity, which process requires the assistance of co-stimulatory second signals on APCs. The immune checkpoint programmed death ligand 1 (PD-L1) not only mediates the immune escape of tumor cells but also acts as a co-inhibitory second signal on APCs. The serious dysfunction of second signals due to the high expression of PD-L1 on APCs in the tumor body results in the inefficiency of tumor vaccines. To overcome this challenge, a previously established Plug-and-Display tumor vaccine platform based on bacterial outer membrane vesicles (OMVs) is developed into an "Antigen Presentation Signal Enhancer" (APSE) by surface-modifying PD-L1 antibodies (αPD-L1). While delivering tumor antigens, APSE can activate the expression of co-stimulatory second signals in APCs due to the high immunogenicity of OMVs. More importantly, the surface-modified αPD-L1 binds to the co-inhibitory signals PD-L1, potentially restoring CD80 function and ensuring efficient co-stimulatory second signals and activation of anti-tumor immunity. The results reveal the importance of PD-L1 blockage in the initiation process of anti-tumor immunity, and the second signal modulation capability of APSE can expand the application potential of cancer vaccines to less immunogenic malignancies.

A clinical study of the immunogenicity and protective potency of a live recombinant GamLPV vaccine for intranasal use for the prevention of whooping cough in adult volunteers

Introduction. The increase in incidence rate of pertussis worldwide, short-term insufficient immunity induced by acellular pertussis vaccines (TDaP) and their failure to provide antibacterial protection and to prevent transmission of infection in human population dictate the development of new pertussis vaccines. A new live recombinant pertussis vaccine for intranasal use (GamLPV) has completed preclinical studies in experiments on nonhuman primates and 2 phases of clinical trials involving adult healthy volunteers, in which the safety, immunogenicity and protective activity of the GamLPV were proven. Method and scheme of vaccine administration have been worked out. Aim. Confirmation of the immunogenicity and protective antibacterial potency of GamLPV in a randomized multicenter clinical trial on adult volunteers. Materials and methods. In this multicenter, clinical, randomized, placebo-controlled, double-blind study 260 healthy adults aged 18–65 years were divided into 2 groups: G1 — 210 volunteers (GamLPV) and G2 — 50 volunteers (placebo). 0.25 ml GamLPV delivered to each nostril (5 × 109 CFU) 60 days apart. Levels of Bordetella pertussis-specific IgG, IgA antibodies in blood serum and levels of B. pertussis-specific secretory IgA antibodies in nasopharyngeal aspirates were measured by ELISA method and agglutination test. The dynamics of elimination of attenuated B. pertussis bacteria after the first and second intranasal administration of GamLPV to volunteers was estimated by using qPCR. Results. Significant seroconversion of B. pertussis-specific IgG and IgA antibodies and growth of B. pertussis-specific secretory IgA antibody levels in nasal aspirates of volunteers were demonstrated. The dynamics of changes in the levels of IgG and IgA antibodies indicates a booster effect after second vaccination. Attenuated B. pertussis bacteria persist in the nose/oropharynx of vaccinated volunteers. The period of elimination after second vaccination is more than 2 times shorter than the period after the first one. The number of persistent B. pertussis bacteria after the second vaccination is less than 3% of the values after the first vaccination. Conclusion. High immunogenicity and the formation of antibacterial protection after single and double intranasal vaccination of GamLPV have been proven.

Plasticity of BioPhi-driven humanness optimization in ScFv-CD99 binding affinity validated through AlphaFold, HADDOCK, and MD simulations.

BioPhi-guided humanization was utilized to enhance the humanness of a humanized single-chain variable fragment targeting CD99, leading to the development of two variants: HuScFvMT99/3BP and HuScFvMT99/3HY. The HuScFvMT99/3BP variant incorporated framework region modifications, leading to modest improvements in humanness, particularly in the VH domain, although the VL domain remained suboptimal. To address this limitation, HuScFvMT99/3HY was designed by combining the VL domain of wild-type with the VH domain of HuScFvMT99/3BP. Molecular dynamics simulations employing AlphaFold2, AlphaFold3, and HADDOCK were performed to evaluate the HuScFv-CD99 peptide complexes. AF2-based simulations demonstrated enhanced binding free energy (ΔGbinding) for both variants compared to HuScFvMT99/3WT. However, ΔGbinding values obtained from AF3 and HD simulations were inconsistent, with HuScFvMT99/3BP exhibiting the weakest binding affinity. While ΔGbinding patterns derived from AlphaFold3 and HADDOCK simulations aligned, amino acid decomposition analysis revealed variations in the interaction coordinates of the predicted complexes. Root-mean-square deviation analysis indicated improved structural stability for HuScFvMT99/3BP (0.975 Å) and HuScFvMT99/3HY (1.075 Å) relative to HuScFvMT99/3WT (1.225 Å). Biolayer interferometry further confirmed that HuScFvMT99/3WT exhibited the highest binding affinity (KD = 1.35 × 10⁻⁷ M) compared to HuScFvMT99/3BP (KD = 2.64 × 10⁻⁷ M) and HuScFvMT99/3HY (KD = 3.95 × 10⁻⁷ M). Supporting evidence was provided by ELISA and flow cytometry experiments. PITHA analysis revealed a high immunogenicity risk for all variants, despite HuScFvMT99/3HY displaying improved humanness, a larger complementarity-determining region (CDR) cavity, and a more hydrophobic CDR-H3 loop. These findings highlight the delicate balance between enhancing humanness and preserving the structural and functional integrity critical for therapeutic antibody development.

Research progress and application of nanobodies

Nanobodies (Nbs), the unique single-domain antibodies discovered in the species of Camelidae and sharks, are also known as the variable domain of the heavy chain of heavy-chain antibody (VHH). They offer strong antigen targeting and binding capabilities and overcome the drawbacks such as large size, low stability, high immunogenicity, and slow clearance of conventional antibodies. Nbs can be boosted by bioconjugation with toxins, enzymes, radioactive nucleotides, fluorophores, and other functional groups, demonstrating potential applications in the diagnosis and treatment of human and animal diseases. This article introduces the structures and characteristics of Nbs, the construction and screening of Nb libraries, and the strategies for affinity maturation and then reviews the current applications of Nbs in diagnosis and treatment, providing a reference for the development of diagnostic reagents and clinical therapies for infectious diseases.

The Mechanism of Adeno-associated Virus (AAV) Gene Therapy

Adeno-associated Virus (AAV) vector has become an important tool for vivo gene therapy due to its high specificity, low immunogenicity and long-term expressibility. There are multiple novel pharmaceuticals utilizing recombinant AAV vectors to treat genetic defect disease or disease related to gene expression disorder that are undergoing clinical trials. In this review, the basic biological features of AAV viruses are introduced, including their structure, classification, and interactions with hosts. This paper aims to elucidate the commonalities and differences among several AAV viruses used in clinical treatment by analyzing existing literature. The relevant genes for transduction of various types of AAV viruses are specifically analyzed in this article. By elaborating the process and mechanism of AAV virus transduction-related gene expression, this paper also attempts to summarize the current achievements of AAV therapy and explain the limitations still existing. It is hoped to contribute to the development and progress of AAV therapy in the future.

Immunoarchitectural Pattern and Its Potential Prognostic Value in Mucoepidermoid Carcinoma.

To define tumor immunoarchitectural patterns (IPs) and characterize the immune profile in salivary gland mucoepidermoid carcinoma (MEC) toward assessing MEC prognostic significance and implications for immunotherapy. This study analyzed 41 MEC cases, evaluating the tumor IPs and tumor-infiltrating lymphocyte (TIL) parameters by using whole-slide imaging and AI-assisted assessment. Immunohistochemistry of CD3 and CD8 markers was performed to assess key lymphocyte subpopulations. Immune-rich (I-rich) tumors were characterized by high TIL density and were associated with aggressive tumor behavior, particularly in histological high-grade MEC, with a significant increase in TIL density observed in the inner invasive margin compartment (p < 0.05). I-rich tumor cases were linked to poorer disease-free survival (DFS) (Breslow = 4.686, p = 0.03). Aggressive MEC cases displayed a highly heterogeneous TIL profile, however, no TIL patterns showed a significant impact on DFS (p > 0.05). Despite the high immunogenicity suggested by the abundance of T lymphocytes, the protective role of CD8+ T lymphocytes was not prominent in MEC. I-rich tumors appeared more aggressive and unfavorable MEC cases exhibited high heterogeneity in their TIL profiles. Interrogating the role of TILs in the inner invasive tumor margin may offer a new mechanistic understanding for future immunotherapy discovery.

Tumor-infiltrating lymphocytes in melanoma: from prognostic assessment to therapeutic applications.

Malignant melanoma, the most aggressive form of skin cancer, is characterized by unpredictable growth patterns, and its mortality rate has remained alarmingly high over recent decades, despite various treatment approaches. One promising strategy for improving outcomes in melanoma patients lies in the early use of biomarkers to predict prognosis. Biomarkers offer a way to gauge patient outlook early in the disease course, facilitating timely, targeted intervention. In recent years, considerable attention has been given to the immune response's role in melanoma, given the tumor's high immunogenicity and potential responsiveness to immunologic treatments. Researchers are focusing on identifying predictive biomarkers by examining both cancer cell biology and immune interactions within the tumor microenvironment (TME). This approach has shed light on tumor-infiltrating lymphocytes (TILs), a type of immune cell found within the tumor. TILs have emerged as a promising area of study for their potential to serve as both a prognostic indicator and therapeutic target in melanoma. The presence of TILs in melanoma tissue can often signal a positive immune response to the cancer, with numerous studies suggesting that TILs may improve patient prognosis. This review delves into the prognostic value of TILs in melanoma, assessing how these immune cells influence patient outcomes. It explores the mechanisms through which TILs interact with melanoma cells and the potential clinical applications of leveraging TILs in treatment strategies. While TILs present a hopeful avenue for prognostication and treatment, there are still challenges. These include understanding the full extent of TIL dynamics within the TME and overcoming limitations in TIL-based therapies. Advancements in TIL characterization methods are also critical to refining TIL-based approaches. By addressing these hurdles, TIL-focused research may pave the way for improved diagnostic and therapeutic options, ultimately offering better outcomes for melanoma patients.

Designing and immunomolecular analysis of a new broad-spectrum multiepitope vaccine against divergent human papillomavirus types.

Human papillomavirus (HPV), which is transmitted through sexual activity, is the primary cause of cervical cancer and the fourth most common type of cancer in women. In this study, an immunoinformatics approach was employed to predict immunodominant epitopes from a diverse array of antigens with the ultimate objective of designing a potent multiepitope vaccine against multiple HPV types. Immunodominant B cell, cytotoxic T cell (CTL), and helper T cell (HTL) epitopes were predicted using bioinformatics tools These epitopes were subsequently analyzed using various immunoinformatics tools, and those that exhibited high antigenicity, immunogenicity, non-allergenicity, non-toxicity, and excellent conservation were selected. The selected epitopes were linked with appropriate linkers and adjuvants to formulate a broad-spectrum multiepitope vaccine candidate against HPV. The stability of the multiepitope vaccine candidate was confirmed through structural analysis, and docking results indicated a high affinity for Toll-like receptors (TLR2 and TLR4). Molecular dynamics simulations demonstrated a persistent interaction of TLR2 and TLR4 with the multiepitope vaccine candidate. In silico immunological simulations showed that three injections of the multiepitope vaccine candidate resulted in high levels of B- and T-cell immune responses. Moreover, the in silico cloning results indicated that the multiepitope vaccine candidate could be expressed in substantial amounts in E. coli. The results of this study imply that designing a broad-spectrum vaccine against various HPV types using computational methods is plausible; however, experimental validation and safety testing to confirm the findings is essential.

Neoantigen sequestrated autophagosomes as therapeutic cancer vaccines

Neoantigens serve as ideal personalized cancer vaccines because of their high immunogenicity, ability to evade central thymic tolerance, and minimal risk of eliciting autoimmune responses. Herein, we describe a genetically engineered autophagosome-based neoantigen vaccine (APNV) in combination with an immune checkpoint inhibitor (anti-PD-1 antibody) for cancer immunotherapy. The APNV was derived from engineered NIH 3T3 cells, which co-express melanoma neoantigens and autophagosome maker microtubule-associated proteins 1 A/1B light chain 3B (LC3), from which the LC3-labeled neoantigen-autophagosomes were isolated. These purified autophagosomes, in conjunction with vaccine adjuvants high-mobility group box 1 (HMGB1) and granulocyte-macrophage colony-stimulating factor (GM-CSF), were integrated into a hydrogel to create an APNV. The APNV effectively activated dendritic cells both in vitro and in vivo. Moreover, APNV, in combination with checkpoint blockade therapy, significantly hampered post-surgical tumor recurrence in a subcutaneous melanoma tumor model and effectively impeded metastatic progression in a melanoma lung metastasis model. This APNV may be conducive to making personalized therapeutic neoantigen vaccines for cancer immunotherapy.

CD7-targeting pro-apoptotic extracellular vesicles: A novel approach for T-cell haematological malignancy therapy.

T-cell haematological malignancies progress rapidly and have a high mortality rate and effective treatments are still lacking. Here, we developed a drug delivery system utilizing 293T cell-derived extracellular vesicles (EVs) modified with an anti-CD7 single-chain variable fragment (αCD7/EVs). Given the challenges of chemotherapy resistance in patients with T-cell malignancy, we selected cytochrome C (CytC) and Bcl2 siRNA (siBcl2) as therapeutic agents and loaded them into αCD7/EVs (αCD7/EVs/CytC/siBcl2). We found that αCD7/EVs efficiently targeted and were internalized by human T-ALL Molt-4 cells. In addition, the interaction between αCD7 and CD7 switched the EV entry pathway in Molt-4 cells from macropinocytosis-dependent endocytosis to clathrin-mediated endocytosis, thereby reducing EV-lysosome colocalization, ultimately improving CytC delivery efficiency and increasing the cytotoxicity of nascent EVs from EV-treated Molt-4 cells. Notably, αCD7/EVs/CytC/siBcl2 demonstrated similar efficacy against both Molt-4 and chemotherapy-resistant Molt-4 cells (CR-Molt-4). Furthermore, αCD7/EVs/CytC/siBcl2 exhibited high safety, low immunogenicity and minimal impact on human T cells. Therefore, αCD7/EVs/CytC/siBcl2 are promising therapeutic approaches for treating CD7+ T-cell malignancies.

PD-1 blockade treatment in melanoma: Mechanism of response and tumor-intrinsic resistance.

Malignant melanoma is characterized by high immunogenicity, genetic heterogeneity, and diverse pathological manifestations, affecting both skin and mucosa over the body. Pembrolizumab and nivolumab, both anti-PD-1 monoclonal antibodies, were approved by the US FDA for unresectable or metastatic melanoma in 2011 and 2014, respectively, with enduring and transformative outcomes. Despite marked clinical achievements, only a subset of patients manifested a complete response. Approximately 55% of melanoma patients exhibited primary resistance to PD-1 antibodies, with nearly 25% developing secondary resistance within 2 years of treatment. Thus, there is a critical need to comprehensively elucidate the mechanisms underlying the efficacy and resistance to PD-1 blockade. This review discusses the fundamental mechanisms of PD-1 blockade, encompassing insights from T cells and B cells, and presents resistance to anti-PD-1 with a particular focus on tumoral-intrinsic mechanisms in melanoma.

Strategies for Modifying Adenoviral Vectors for Gene Therapy.

Adenoviral vectors (AdVs) are effective vectors for gene therapy due to their broad tropism, large capacity, and high transduction efficiency, making them widely used as oncolytic vectors and for creating vector-based vaccines. This review also considers the application of adenoviral vectors in oncolytic virotherapy and gene therapy for inherited diseases, analyzing strategies to enhance their efficacy and specificity. However, despite significant progress in this field, the use of adenoviral vectors is limited by their high immunogenicity, low specificity to certain cell types, and limited duration of transgene expression. Various strategies and technologies aimed at improving the characteristics of adenoviral vectors are being developed to overcome these limitations. Significant attention is being paid to the creation of tissue-specific promoters, which allow for the controlled expression of transgenes, as well as capsid modifications that enhance tropism to target cells, which also play a key role in reducing immunogenicity and increasing the efficiency of gene delivery. This review focuses on modern approaches to adenoviral vector modifications made to enhance their effectiveness in gene therapy, analyzing the current achievements, challenges, and prospects for applying these technologies in clinical practice, as well as identifying future research directions necessary for successful clinical implementation.

Attenuated Getah virus confers protection against multiple arthritogenic alphaviruses.

Alphaviruses are important arthropod-transmitted pathogens of humans and livestock. Getah virus (GETV) is an arthritogenic alphavirus that causes disease in horses and piglets; it also poses a potential threat to humans. A live attenuated vaccine candidate named GETV-3ΔS2-CM1, harbouring a deletion in nonstructural protein 3 and substitutions in the capsid protein, is genetically stable and exhibits robust immunogenicity. It was shown to confer passive protection to piglets born to immunized sows. In mice, a single dose of GETV-3ΔS2-CM1 protected against infection with different strains of GETV, Semliki Forest virus, Ross River virus, o'nyong'nyong virus, chikungunya virus, and Barmah Forest virus. Chimaeras based on the GETV-3ΔS2-CM1 backbone maintained both the attenuated phenotype and high immunogenicity. The safety, efficacy, and ability to induce protection against multiple alphaviruses highlights the potential of GETV-3ΔS2-CM1 and chimaeras using this backbone as promising vaccine candidates. By contributing simultaneously to the wellbeing of animals and humans, our universal next generation vaccine strategy helps to achieve "One Health" goals.

Research on the TSPAN6 regulating the secretion of ADSCs-Exos through syntenin-1 and promoting wound healing

BackgroundExosomes (Exos) from adipose-derived stem cells (ADSCs) have a high inclusion content and low immunogenicity, which helps to control inflammation and accelerate the healing of wounds. Unfortunately, the yield of exosomes is poor, which raises the expense and lengthens the treatment period in addition to impairing exosomes’ therapeutic impact. Thus, one of the key problems that needs to be resolved in the current exosome study is increasing the exosome yield.MethodsTetraspanin-6 (TSPAN6) overexpression and knockdown models of ADSCs were constructed to determine the number of exosomes secreted by each group of cells as well as the number of multivesicular bodies (MVBs) and intraluminal vesicles (ILVs) within the cells. Subsequently, the binding region of the interaction between TSPAN6 and syntenin-1 was identified using the yeast two-hybrid assay, and the interaction itself was identified by immunoprecipitation. Finally, cellular and animal studies were conducted to investigate the role of each class of exosomes.ResultsWhen compared to the control group, the number of intracellular MVBs and ILVs was significantly larger, and the number of ADSCsTSPAN6+-Exos was more than three times higher. However, TSPAN6’s ability to stimulate exosome secretion was reduced as a result of syntenin-1 knockdown. Additional yeast two-hybrid assay demonstrated that the critical structures for their interaction were the N-terminal, Postsynaptic density protein 95/Discs large protein/Zonula occludens 1 (PDZ1), and PDZ2 domains of syntenin-1, and the C-terminal of TSPAN6. In animal trials, the wound healing rate was best in the ADSCsTSPAN6+-Exos group, while cellular experiments demonstrated that ADSCsTSPAN6+-Exos better enhanced the proliferation and migration of human skin fibroblasts (HSFs) and human umbilical vein endothelial cells (HUVECs).ConclusionTSPAN6 stimulates exosome secretion and formation, as well as the creation of MVBs and ILVs in ADSCs. Syntenin-1 is essential for TSPAN6’s stimulation of ADSCs-Exos secretion. Furthermore, ADSCsTSPAN6+-Exos has a greater ability to support wound healing, angiogenesis, and the proliferation and migration of a variety of cells.

The unexpected PD-L1 suppression function of celery-derived extracellular vesicles improves lung cancer chemotherapy efficacy.

Aim: The article explores celery-derived extracellular vesicles (CDEVs), characterized by high cellular uptake, low immunogenicity, and high stability, as a therapeutic strategy for antitumor nanomedicines. Methods: The methods employed in this study include in vitro cell experiments such as co-culture, Western Blot, and flow cytometry. In vivo experiments were conducted in C57BL/6 tumor-bearing mice subcutaneously injected with Lewis lung carcinoma (LLC) cells. The experiments encompassed parameters such as survival rate, body weight, tumor size, flow cytometry, immunohistochemistry, and spectral live imaging system. Results: Our study revealed that CDEVs could be used as drugs to effectively downregulate the phosphorylated signal transducer and activator of transcription 3 (p-STAT3)/programmed cell death ligand 1 (PD-L1) axis in lung cancer cells. In co-culture experiments, CDEVs were observed to impede the expression of PD-L1, thereby interfering with the interaction between PD-L1 and programmed death 1 (PD-1) and subsequently preventing the suppression of T cells. In in vivo distribution experiments, CDEVs loaded with paclitaxel (PTX) demonstrated better tumor targeting capabilities. Remarkably, following CDEVs-PTX treatment, CD8+ T cell levels in mice were increased, presumably leading to improved antitumor effects. Conclusion: CDEVs not only serve as drug carriers but also function as drugs themselves; as such, through a single administration of CDEVs, it is possible to combine immunotherapy and chemotherapy to achieve better effects between the two, providing a more comprehensive and effective cancer treatment strategy that promises to improve treatment outcomes and reduce the adverse effects of therapy.

Impact of Ligand Concentration on the Properties of Nucleic-Acid-Encapsulated MOFs and Inflammation Modulation in Prostate Cancer Cells.

The zeolitic imidazolate framework (ZIF) is one of the most explored metal-organic-framework-based systems for nucleic acid delivery to cancer cells. Current nucleic acid delivery tools exhibit several drawbacks, such as high manufacturing costs, endosomal entrapment, toxicity, and immunogenicity. However, the biomimetic mineralization of Zn-based ZIFs offers a low-cost and facile encapsulation of nucleic acids at room temperature in aqueous conditions. The efficiency of nucleic acid delivery and its subsequent impact on inflammation in cells are influenced by the physicochemical properties of the material. The imidazole content determines the formation and crystallinity of ZIF, and an optimal ratio ensures the formation of well-defined and highly crystalline structures. In this study, a series of siRNA-encapsulated ZIFs (siRNA@ZIF) were systematically prepared by varying ligand-to-metal (L/M) molar ratios. Our study demonstrates that variations in ligand concentrations influence the crystalline structures, particle size, and shape of siRNA@ZIF particles. At low L/M, two-dimensional siRNA@ZIF particles form with a size of 1 μm. As the L/M ratio increases gradually, the particle size decreases, resulting in three-dimensional particles ∼200 nm in size. We also observed better stability of siRNA@ZIF in water prepared using high L/M values and time-dependent cellular uptake by the cells. Additionally, no significant impact of the biocomposites on inflammation was found, indicating the lack of an unwanted immune response and nonimmunotoxic nature over longer periods (96 h). These findings highlight the necessity of fine-tuning ligand concentrations and synthesis chemistry in designing efficient and optimal ZIF-based systems as versatile delivery platforms for nucleic acids.