Search Results (572)

Next-generation vaccines are being developed to elicit durable and cross-protective immune responses against diverse pathogens, particularly those targeting the respiratory and enteric systems. By strategically engaging T cell-centric antigen design, mucosal immune engagement, and induction of trained innate immunity, these innovative platforms are expected to reshape the paradigm of immunoprophylaxis and to offer promising avenues for enhanced protection against complex infectious diseases. Conventional antibody-based vaccines, though effective against many infections, often lack the capacity to induce durable or cross-protective immunity at mucosal surfaces. Advances in antigen design, delivery platforms, and adjuvant technologies now facilitate precise activation of tissue-resident memory T cells and enhancement of mucosal secretory IgA responses, thereby achieving sterilizing immunity at barrier surfaces while reinforcing systemic immune protection. Advanced delivery platforms, including lipid nanoparticles, viral vectors, and nano or liposomal carriers, further refine antigen presentation, enhancing stability, targeting, and overall immunogenicity. Concurrently, progress in understanding trained innate immunity highlights opportunities to induce broad, non-antigen-specific protection through epigenetic and metabolic reprogramming of innate cells. The integration of these adaptive and innate mechanisms may enhance early pathogen control, limits transmission, and strengthens defense against variant and antimicrobial-resistant pathogens across diverse populations. However, translating these immunological insights into safe, scalable, and globally accessible vaccines remains a major challenge. This review explores the emerging conceptual framework of next-generation vaccines that demonstrate partial integration of these axes in preclinical models, though human translation and functional synergy require Phase II validation. It highlights progress toward next-generation vaccines leveraging integrated adaptive and innate immune reprogramming for superior protection against respiratory and enteric pathogens. Full article

Highly pathogenic avian influenza A (H7N9) remains a threat to poultry health and poses a zoonotic risk, highlighting the need for vaccine antigens capable of inducing both systemic and mucosal immunity. In this study, we evaluated X33CLS-H7, a clarified cell-lysate supernatant derived from glycoengineered Pichia pastoris expressing H7 hemagglutinin, in BALB/c mice following intramuscular(i.m.) injection, nebulized inhalation, or intranasal instillation. H7 expression and hemagglutination activity were confirmed by Western blotting and hemagglutination assay, respectively. Serum HA7-specific IgG and IgA responses, hemagglutination inhibition(HI) activity, H7N9 pseudovirus neutralization, bronchoalveolar lavage fluid (BALF) antibodies, and safety readouts were assessed. After two i.m. immunizations, X33CLS-H7 induced the strongest systemic antibody responses, with an HI geometric mean titer of 1:1622 95% CI, 1:1108–1:2348 and a mean log10 NT₅₀ of 4.62. Respiratory immunization also elicited antibody responses. After four doses, high-dose nebulized delivery produced the strongest responses among the respiratory delivery regimens, with serum IgG and IgA titers of 1.02 × 10⁵ and 2.24 × 10³, respectively, an endpoint HI GMT r of 1:457 95% CI, 1:211–1:971, and a mean log10 NT₅₀ of 3.77 compared with 2.02 in saline controls. High-dose nebulized delivery also generated detectable HA7-specific IgG and IgA responses in bronchoalveolar lavage fluid. No overt local or systemic toxicity signals were observed under the tested conditions. These findings indicate that X33CLS-H7 retains HA7-associated antigenicity and can induce systemic and respiratory mucosal antibody responses, supporting its further evaluation as a simplified and scalable H7N9 vaccine antigen candidate. Full article

Background: Effective vaccines are essential to overcome the limitations of livestock immunisation, particularly in low- and middle-income countries (LMICs), where scalable, thermostable, and easy-to-administer solutions are needed. Nanoparticle-based delivery systems, such as the Spontaneous Nanoliposome Antigen Particle (SNAP) technology using CoPoP liposomes, offer a promising alternative for subunit vaccine development, although their performance in large animal species remains poorly characterised. CoPoP enables the rapid non-covalent multimeric display of His-tagged protein antigens combined with immunomodulators on liposomes incorporating cobalt porphyrin–phospholipid (CoPoP). Objective: To evaluate the immunogenicity of CoPoP-based liposomes delivering the Theileria parva p67C antigen in cattle and compare their performance in murine models. Methods: Cattle and mice were immunised with p67C formulated in CoPoP liposomes incorporating QS-21 and/or PHAD immunomodulators. Humoral and cellular responses were assessed. Parallel in vitro stimulation of bovine PBMC with Quil-A was used to investigate the mechanistic effects of saponins on bovine cells. Results: CoPoP liposome formulations did not improve p67C immunogenicity in cattle, with antibody responses at least two-fold lower than previously reported results and no detectable cellular responses. In contrast, the same platform induced up to 2000-fold higher antibody titres in mice. This disparity is likely driven by differences in antigen dose relative to body mass, tissue architecture, lymphatic accessibility, and innate immune signalling differences. PHAD-mediated TLR4 activation appeared less effective in cattle, whereas QS-21 induced a broader immune activation, likely through conserved inflammasome pathways. Despite limited immunogenicity, antigen presentation by CoPoP liposomes was preserved. Conclusions: SNAP-based CoPoP liposomes showed strong immunogenicity in mice but limited efficacy in cattle, highlighting the challenges of cross-species translation. Optimisation of antigen dose and adjuvant selection for the targeted species is required, with QS-21 representing a more promising candidate than the TLR4 agonist. The scalability and versatility of SNAP technology support its continued development for multivalent livestock vaccines. Full article

Bacterial membrane vesicles (BMVs), encompassing outer membrane vesicles (OMVs) released from Gram-negative bacteria and extracellular vesicles (EVs) released from Gram-positive bacteria, have emerged as promising vaccine platforms owing to their intrinsic immunostimulatory properties and capacity to deliver a wide range of antigens. Although conventional vaccines effectively prevent infectious diseases, their long-term efficacy is often limited by antigenic variation and reliance on a restricted number of licensed adjuvants. BMVs, as self-adjuvanting systems, enable both antigen delivery and innate immune activation. BMVs are nanoscale lipid bilayer structures enriched with pathogen-associated molecular patterns (PAMPs), facilitating their recognition and uptake by antigen-presenting cells. This leads to the activation of pattern recognition receptors and the induction of pro-inflammatory cytokines, type I interferons, and adaptive immune responses, including antibody production and Th1- and Th17-biased cellular immunity. Recent studies highlight the versatility of BMVs as vaccine platforms across bacterial, fungal, and viral infection models. BMVs induce protective immunity by promoting both systemic and mucosal immune responses, thereby reducing bacterial burden and limiting pathogen colonization across diverse infection models. These properties have supported their application in viral vaccine development, including influenza and SARS-CoV-2, with the potential to enhance mucosal immunity. Despite these advantages, challenges remain in standardization, safety, and antigen-loading efficiency. Engineered BMVs incorporating protein or mRNA antigens may further enhance antigen presentation and CD8⁺ T cell responses. This review summarizes the biological features, immunological mechanisms, and future potential of BMVs in vaccine development. Full article

Living therapies, including chimeric antigen receptor T (CAR-T) cells, oncolytic viruses (OVs), and bacteria-based platforms, are emerging as promising approaches in cancer treatment because they can directly target tumors and modulate anti-tumor immunity. This narrative review summarizes current knowledge on these therapies, focusing on their mechanisms of action, therapeutic applications, major limitations, and recent advances in genetic engineering, synthetic biology, and delivery systems. CAR-T cell therapy has shown substantial clinical success in hematological malignancies through the genetic redirection of T cells against tumor-associated antigens, although its efficacy in solid tumors remains limited by antigen heterogeneity and the immunosuppressive tumor microenvironment (TME). OVs selectively infect and lyse malignant cells while also stimulating local and systemic immune responses, and engineered OVs may further enhance therapeutic activity by reshaping the TME. Bacteria-based therapies exploit the natural tumor-targeting ability of selected strains, particularly in hypoxic regions, to deliver therapeutic agents and activate immune responses. Despite encouraging progress, safety concerns, immune-related barriers, and tumor complexity remain major challenges. Overall, integrating living therapies with modern biotechnological advances and existing treatment modalities may support more personalized and synergistic strategies for cancer management. Full article

Bone metastases remain one of the most clinically devastating complications of advanced cancer, particularly in breast, prostate, and lung malignancies, where they drive pain, fractures, hypercalcemia, and progressive functional decline. Their management is further complicated by a highly immunosuppressive bone microenvironment characterized by osteoclast-driven bone destruction, myeloid cell dominance, impaired antigen presentation, and weak effector T-cell infiltration, all of which limit the activity of conventional immunotherapies. In this setting, nanoparticles are emerging not merely as passive drug carriers but as programmable platforms capable of reshaping the metastatic niche. This review discusses how bone-targeted and immune-responsive nanocarriers can improve therapeutic precision through hydroxyapatite-binding ligands, dual-targeting strategies, stealth coatings, enzyme- and pH-responsive release systems, and externally guided platforms. We further examine how these systems modulate key immune compartments within bone metastases, including reprogramming tumor-associated macrophages and myeloid-derived suppressor cells, restoring cytotoxic T-cell activity, enhancing dendritic-cell activation, and enabling in situ vaccination through photothermal or photodynamic immunogenic cell death. Particular attention is given to the delivery of checkpoint inhibitors, cytokines, siRNA/miRNA, mRNA, and clustered regularly interspaced short palindromic repeats (CRISPR)-based payloads, as well as to the rational combination of these with chemotherapy, bone-modifying agents, and radiotherapy. Finally, we highlight major translational barriers, including lesion heterogeneity, limited penetration into mineralized tissue, off-target immune effects, manufacturing complexity, and the continued lack of bone-specific preclinical and clinical validation. Collectively, immunomodulatory nanoparticles represent a promising strategy to convert bone metastases from immune-refractory sites into more therapeutically responsive lesions. Full article

Antibody–drug conjugates (ADCs) are a rapidly evolving class of oncology therapeutics that enable precise delivery of potent cytotoxic agents to tumor cells while minimizing systemic toxicity. While HER2-targeted ADCs such as trastuzumab deruxtecan (T-DXd) in HER2-mutant, Datopotamab deruxtecan (Dato-Dxd) in EGFR-mutant, and telisotumumab vedotin (Teliso-V) in MET IHC 3+ expressing lung cancer have already established a clinical role in non-small cell lung cancer (NSCLC), multiple ADCs targeting alternative antigens, including additional TROP2 ADCs, HER3, MET, CEACAM5, B7-H3, Nectin-4, and others, are now in advanced clinical development. This review synthesizes the current evidence for non-HER2 ADCs in NSCLC, highlighting mechanisms of action, clinical efficacy, safety profiles, biomarker strategies, and emerging resistance mechanisms. Key safety concerns, including interstitial lung disease (ILD), ocular toxicity, and peripheral neuropathy, are emphasized alongside approaches for re-challenge following toxicity. We further discuss next-generation ADC platforms, including bispecific and conditionally activated constructs, as well as combination strategies with immunotherapy. Collectively, ADCs beyond HER2 are poised to reshape treatment paradigms in NSCLC, offering hope for patients with limited therapeutic options. This review identifies current gaps, highlights ongoing research priorities, and proposes practical considerations for integrating these therapies into clinical practice. Full article

Background: Edwardsiella piscicida is a significant intracellular pathogen of channel catfish (Ictalurus punctatus) and a major threat to U.S. aquaculture. A recently developed recombinant attenuated vaccine strain (χ16016) uses arabinose-regulated murA expression to trigger delayed cell wall lysis in vivo, ensuring biological containment while conferring strong protection against virulent challenge. Although its efficacy has been demonstrated, the host immune programs underlying protection remain incompletely defined. Methods: We used RNA sequencing to characterize tissue-specific transcriptomic responses in the intestines and kidneys of channel catfish at 7 days post-vaccination. Fish were vaccinated with χ16016 by either bath immersion or intracoelomic (IC) injection, and differentially expressed genes and enriched immune pathways were analyzed to determine how the vaccine delivery route shapes systemic and mucosal immune responses. Results: Across comparisons, 19,101 differentially expressed genes revealed pronounced route- and tissue-dependent immune remodeling. As aquaculture vaccination strategies increasingly prioritize scalability and practical deployment, understanding how the delivery route shapes immune outcomes is critical. Here, IC vaccination induced broader systemic transcriptional changes, particularly in the intestine, whereas bath immunization elicited a more focused yet coordinated mucosal response. Overall, intestinal tissue exhibited greater transcriptional responsiveness than kidney tissue, underscoring its central role in early vaccine-induced immunity. Functional enrichment analyses identified the activation of innate recognition pathways, MAPK and calcium signaling cascades, complement components, antigen processing machinery, and cell adhesion networks. Notably, bath immunization enriched the intestinal immune network for IgA production pathway, which represents an orthology-based mapping of conserved mucosal immune components, alongside the upregulation of IL-6, CXCL12–CXCR4, integrins (α4β7), MHC class II, complement C3, and polymeric immunoglobulin receptor (pIgR). Given that catfish rely primarily on IgM in mucosal immunity, these findings indicate the induction of IgM-mediated mucosal defense rather than classical mammalian IgA responses. Concurrent complement and scavenger receptor signatures suggest a transition toward efficient opsonophagocytic clearance with controlled inflammation at this subacute stage. Conclusions: This study provides the first systems-level view of host transcriptomic responses to a regulated-lysis E. piscicida vaccine in channel catfish. The findings demonstrate that immersion vaccination, although transcriptionally less expansive than injection, effectively activates coordinated mucosal innate and adaptive immune programs, supporting its practical use as a scalable vaccination strategy for aquaculture. Full article

Chronic inflammatory diseases and autoimmune diseases are overlapping but distinct immune-mediated disorders that represent a growing worldwide health concern, characterised by persistent inflammation, tissue damage, and progressive organ dysfunction. In the United States alone, more than $180 billion is spent annually on managing these conditions, yet fewer than 10% of patients achieve long-term remission. These figures highlight the limitations of conventional therapies, which often control symptoms rather than adequately modify the underlying disease process. This review provides a focused and comparative overview of emerging therapeutic strategies across representative immune-mediated disorders, with particular emphasis on mesenchymal stem cells, Janus kinase-signal transducer and activator of transcription (JAK-STAT) inhibitors, chimeric antigen receptor T-cell therapies, therapeutic vaccines, microbiome-modulating interventions, and nanotechnology-based drug delivery systems. In parallel, artificial intelligence (AI) is increasingly contributing to biomarker discovery, drug repurposing, and treatment stratification, thereby supporting the development of predictive and personalised medicine. Overall, these advances support a shift toward mechanism-based, multimodal, and more durable treatment strategies, although further clinical validation remains necessary. Full article

Background/Objectives: Vaccination is a critical public health intervention, yet its global implementation is hindered by high production costs and cold-chain requirements. This review aims to evaluate plant-based systems as sustainable, cost-efficient alternatives for vaccine production. Methods: A comprehensive literature search was conducted across major databases (PubMed, Scopus, Web of Science). The peer-reviewed references were critically assessed, focusing on molecular expression strategies, phytochemical immunomodulators, and plant-mediated oral delivery. Results: Plant and microalgae systems effectively support nuclear, chloroplast, and transient expression of diverse antigens. Furthermore, specific plant-derived compounds were found to act as potent adjuvants and immunostimulants, enhancing the immunogenicity of vaccine formulations. Edible plant tissues also provide a viable platform for oral delivery, reducing the need for extensive purification and refrigerated logistics. Conclusions: Integrating recombinant expression technologies with bioactive plant metabolites offers a flexible and scalable foundation for next-generation vaccines. These biological platforms show promise for addressing some immunization challenges, particularly in low-resource settings. Full article

Background: The end of the COVID-19 public health emergency of international concern (PHEIC) in May 2023 marked a transition from disruption to recovery and rebuilding of health systems. The WHO African Region entered this period with declining routine immunization coverage, widening inequities, and fragile surveillance systems. We conducted a critical narrative synthesis of post-PHEIC recovery and the transformation of immunization systems in the region from 2023 to 2025. Methods: We thematically analyzed publicly available data from the WHO and other sources using a systems-oriented framework covering immunization coverage, equity, vaccine introductions, disease control, governance, financing, and data systems. Results: Regional coverage for most antigens was restored to 2019 pre-pandemic levels by 2024, e.g., three doses of diphtheria-tetanus-pertussis-containing vaccines at 76%. However, progress remains insufficient to meet the Immunization Agenda 2030 (IA2030) target of 90% coverage. In addition, there were 6.7 million zero-dose children in the 2024 birth cohort (6.3% higher than the 6.3 million in 2019), concentrated in a few countries. The IA2030 target is a 50% reduction in the number of zero-dose children by 2030, compared to 2019. Recovery initiatives have restored services, while accelerated introductions (e.g., malaria vaccines introduced in 20 new countries in 2024–2025) signal renewed system momentum. Yet, progress has plateaued at pre-pandemic levels, reflecting structural constraints rather than sustained transformation. Concurrently, recurrent outbreaks of measles, yellow fever, and other vaccine-preventable diseases highlight persistent immunity gaps and surveillance limitations. Structural constraints (including financing fragility, subnational inequities, and system fragmentation) continue to limit sustained progress. Conclusion: This study offers important insights that can inform immunization policymaking in the WHO African Region and beyond. Current post-PHEIC trends reflect recovery without transformation. Achieving IA2030 targets will require a shift from broad coverage expansion to precision delivery approaches that prioritize zero-dose and underserved populations. Immunization must be positioned as a central pillar of primary health care and health security systems. Full article

Genetically modified (GM) lactic acid bacteria (LAB) are gaining attention as tools for innovation in the food sector, health applications, and industrial processes. LAB have long been used safely due to their GRAS/QPS status, making them suitable for improving fermentation and synthesizing specific and beneficial metabolites. Advances in genomics and gene editing have significantly expanded the available tools, ranging from classical mutagenesis to site-specific recombination, homologous recombination in non-coding regions, CRISPR-based systems, and food-grade chromosomal integration. These approaches enable the insertion of desired genes and the development of engineered strains with tailored functionalities. GM-LAB are also being studied as live delivery systems for therapeutic molecules, including cytokines, hormones, antimicrobial peptides, and vaccine antigens. Engineered strains of Lactococcus lactis and Lactobacillus spp. have yielded promising outcomes in applications such as mucosal immunization, modulation of inflammatory and metabolic responses, and inhibition of pathogenic microorganisms, including multidrug-resistant bacteria. From an industrial perspective, several studies highlight their potential for cost-effective recombinant protein production and the synthesis of high-value metabolites through fermentation. However, within the European Union, their use is subject to stringent regulatory oversight, requiring comprehensive molecular and environmental risk assessments, careful evaluation of horizontal gene transfer, and a preference for markerless chromosomal integrations. Despite these constraints, GM-LAB offer significant potential to improve food quality, sustainability, and human health. Full article

Diffuse midline gliomas (DMGs) are rare but highly aggressive central nervous system (CNS) tumors that can present in both pediatric and adult populations. These tumors were redefined in the 2016 WHO classification of CNS tumors based on integrated histopathological and molecular features, and were initially designated as “DMG, H3 K27M-mutant”. In the 2021 WHO update, DMGs were incorporated into the newly defined category of primarily pediatric-type diffuse high-grade gliomas, and nomenclature was changed to “DMG, H3 K27-altered” to encompass additional molecular drivers beyond the canonical H3 K27M mutation. Clinically, DMGs arise as expansile, infiltrating tumors within midline structures and may present as non-enhancing or enhancing lesions on imaging. Diagnosis is based on neuroimaging and molecular confirmation by immunohistochemistry or sequencing when tissue is available. DMGs are categorized as WHO grade 4 malignant tumors due to their aggressive biology leading to rapid and infiltrative growth. Owing to their deep and midline location, surgical resection is typically not feasible. Radiation therapy is the backbone of treatment, but there is no standard regimen of chemotherapy that has demonstrated durable efficacy. Recent progress in therapeutic approaches has led to a major breakthrough on 6 August 2025 when the U.S. Food and Drug Administration granted the accelerated approval of dordaviprone (ONC201), marking it as the first systemic therapy for progressive DMG harboring H3 K27M mutation. Other novel approaches, including chimeric antigen receptor (CAR) T-cell directed therapies and convection-enhanced delivery, are actively under investigation. We aim to comprehensively review DMGs, including the recent insights into their biology, the evolving therapeutic landscape, and the opportunities to fuel this new momentum against one of the most formidable gliomas. Full article

Alveolar echinococcosis (AE), caused by Echinococcus multilocularis larvae, is a severe zoonotic disease mimicking tumors, primarily affecting the liver with high mortality if untreated. Host immunity plays a pivotal role, shifting from Th1/Th17-mediated clearance to Th2/Treg-driven tolerance, enabling parasite survival. Liver macrophages, including Kupffer cells, polarize towards M2 phenotype under parasite antigens (e.g., phytic acid, exosomes), promoting immunosuppression, fibrosis, and T cell exhaustion via IL-10/TGF-β. This reshapes the tumor-like immune microenvironment with M2 macrophages recruiting Tregs, suppressing NK/DC functions, and fostering angiogenesis/fibrosis. Current treatment remains centered on surgery and benzimidazole therapy, both of which have notable limitations. Experimental immunomodulatory strategies, drug repurposing approaches, and targeted delivery systems may offer future therapeutic opportunities, but these concepts remain largely preclinical, unproven in AE, and require careful evaluation for safety and efficacy. Full article

Background: Crimean-Congo hemorrhagic fever (CCHF) is a severe tick-borne viral disease with a high fatality rate, and no licensed vaccines are currently available. The nucleoprotein (NP) of the Crimean-Congo hemorrhagic fever virus (CCHFV) plays a critical role in viral replication and immune recognition, making it a promising target for vaccine development. This study aimed to design and evaluate a multiepitope recombinant DNA vaccine targeting the NP of CCHFV. Methods: Cytotoxic T lymphocyte (CTL) epitopes from the NP were predicted via immunoinformatics approaches and systematically assessed for antigenicity, allergenicity, toxicity, hydrophobicity, and global population coverage. The selected epitopes were incorporated into four DNA vaccine constructs driven by a cytomegalovirus promoter, adjuvanted with human β-defensin 3 (hBD3), and fused to the reporter protein mRuby3. The constructs were evaluated in vitro using a fluorescent reporter system designed to provide a readout of TCR signaling upon the co-culture of T lymphocytes with differentiated monocytic cells expressing antigens. In vivo immunogenicity and protective efficacy were assessed in BALB/c (exploratory pilot) and IFNAR^−/− mice, a highly susceptible model for viral infection. Cytokine responses were measured to assess immunogenicity. Results: In vitro assays showed predominantly antigen-independent T-cell activation, suggesting that nonspecific stimulation inherent to the reporter co-culture system likely obscured the detection of antigen-specific TCR signaling. In vivo analyses in BALB/c mice revealed that the constructs elicited only modest systemic cytokine profiles while CCHFV-specific IgG and IFN-γ secretion remained undetectable, indicating that antigen-specific T-cell and antibody responses were limited. In the IFNAR^−/− challenge model, several peptide groups achieved significant 2–3 log reductions in tissue viral RNA and infectious titers (p < 0.05 vs. sham). However, the observed viral modulations were insufficient to reach the protective threshold and did not translate to a survival benefit (0%). Conclusion: Despite a rational in silico foundation, the multiepitope DNA vaccine constructs demonstrated limitations in inducing potent, antigen-specific immunity across both mouse models. The lack of antigen-specific responses indicates limitations in epitope selection, construct design, and delivery strategies, requiring optimization of next-generation epitope-based vaccines. These findings highlight the complexity of translating computational epitope predictions into functional vaccines, and provide benchmark data as a framework to guide future optimizations. Full article