Search Results (37)

Human papillomavirus type 53 (HPV53) is one of the most prevalent HPV genotypes in China, frequently detected in cervical intraepithelial neoplasia and cervical cancer, yet remains outside the coverage of all currently available prophylactic vaccines and is relatively understudied. This study performed a comprehensive analysis of HPV53 clinical infection profiles, genomic diversity, and T-cell epitopes to inform therapeutic vaccine development. Clinical analysis of 158 HPV53-positive patients showed that infections were most prevalent in women aged 40–59 years, with persistent infection identified in 13.3% participants and a subset of cases associated with cervical lesions. Genomic analysis of 134 HPV53 isolates identified four lineages (A-D, with lineage D further subdivided into four sublineages, and an overall nucleotide variability of 4.4%. E2 was the most variable protein while E7 was the most conserved. Immunoinformatic prediction identified 176 HLA class I-restricted T-cell epitopes across E6, E7, E1, and E2, from which 20 candidates were selected for experimental validation. Ten demonstrated strong HLA binding affinity in vitro, and murine immunization identified a E6 peptide VYNFAYTDL as an immunodominant epitope. Three validated epitopes exhibited sequence overlap with 12 to 13 of other 13 high-risk HPV genotypes, suggesting their potential as broadly cross-reactive targets. These findings clarify the genomic diversity and immunogenic epitope landscape of HPV53, providing a foundation for the rational design of therapeutic vaccines. Full article

Gold nanoparticles (AuNPs) have emerged as versatile antiviral nanoplatforms because their size, morphology, plasmonic properties, and surface chemistry can be precisely engineered. In this review, we summarize the core design principles of antiviral AuNPs from a structure–function–mechanism perspective. We first outline representative synthetic and interface-programming routes for AuNP preparation, including citrate reduction, Brust–Schiffrin synthesis, seed-mediated growth, green synthesis, direct thiol-conjugation, and mixed-ligand shell strategies, emphasizing how these approaches define particle size, morphology, surface accessibility, interfacial composition, and downstream biofunctionalization potential. We then discuss major surface engineering strategies, including polyethylene glycol, nucleic acids, antibodies and nanobodies, peptides, glycans, antiviral drugs, and biomimetic coatings, with particular attention to how ligand density, orientation, flexibility, and interfacial stability determine biological performance. Next, we examine how functionalized AuNPs inhibit different stages of the viral life cycle, including viral attachment and entry, intracellular replication, assembly and egress, photothermal inactivation, and immune modulation or vaccine delivery. Finally, we highlight current challenges, including incomplete structure–activity relationships, dynamic nano–bio interactions under physiological conditions, limited standardization across studies, and translational barriers related to safety, reproducibility, and scale-up. This review provides a conceptual framework for the rational development of next-generation AuNP-based antiviral nanotherapeutics. Full article

African swine fever in both domestic and wild pig populations is caused by the extremely infectious African swine fever virus (ASFV). It seriously endangers biodiversity and results in large financial losses for the worldwide pork sector. The major capsid protein p72 is molecularly chaperoned by the ASFV pB602L protein, which is essential to viral assembly. Furthermore, as a nonstructural protein expressed at late stages of infection, pB602L induces a distinct antibody response that may complement existing serological assays based on structural proteins. Given its strong immunogenicity, pB602L represents a promising antigen for developing supplementary diagnostic tools for African swine fever (ASF). In this study, we successfully generated and separated the ASFV pB602L protein, and we verified its responsiveness using serum from pigs infected with ASFV. Additionally, we produced four monoclonal antibody-specific hybridoma cell lines that targeted the pB602L protein exclusively. These cell lines demonstrated high immunoreactivity and responsiveness toward ASFV pB602L. These results highlight the potential enhancement of diagnostic skills. We have detected two previously unknown linear B-cell epitopes (¹³⁸TIDSFL¹⁴³ and ¹⁶⁴TNVDTC¹⁶⁹) using overlapping peptide and truncated protein fragment analysis. Due to their high degree of conservation across various ASFV strains, these epitopes offer trustworthy candidates for the creation of particular diagnostic instruments. This study expands the known ASFV antigenic repertoire by systematically mapping immunodominant epitopes of pB602L. The identified epitopes provide potential molecular targets for the rational design of multi-epitope subunit vaccines. Full article

α-synuclein (α-syn) aggregation in dopaminergic neurons is a central event in Parkinson’s disease (PD) pathogenesis. Immunotherapeutic strategies targeting α-syn, including passive and active approaches, aim to inhibit aggregation, propagation, and toxicity of pathological species while promoting their clearance via immune mechanisms. This review summarizes α-syn directed immunotherapies evaluated in in silico, in vitro, and in vivo models, as well as early phase clinical trials, focusing on how epitope selection and antibody formats influence efficacy, safety, and target engagement. Data on monoclonal antibody, peptide, and protein-based vaccines, and structure-guided immunogens were analyzed, integrating behavioral, neuropathological, proteomic, and structural outcomes alongside biomarker development for α-syn species in cerebrospinal fluid and peripheral compartments. Clinical evidence indicates that several candidates induce sustained anti-α-syn antibody responses with acceptable safety profiles and signs of pharmacodynamic engagement, including reductions in free or oligomeric α-syn. However, consistent long-term clinical benefits remain unproven, highlighting the gap between preclinical success and disease modification in humans. Advances in structural biology and proteomics support rational epitope selection and improved immunogen design, reinforcing α-syn-targeted immunotherapy as a promising yet experimental strategy for PD, and highlighting the need for mechanistically oriented, biomarker-driven clinical trials initiated in well-characterized prodromal and early-stage cohorts. Full article

Background: Tuberculosis (TB) remains a major global health challenge, highlighting the urgent need for more effective vaccines. This study aimed to develop an artificial intelligence-guided epitope prediction and prioritization pipeline to identify immunodominant peptides from Mycobacterium tuberculosis (Mtb) and to evaluate the immunogenicity and protective efficacy of the resulting vaccine candidates. Methods: An AI-guided framework was used to predict and prioritize immunodominant Mtb epitopes, leading to the generation of 72 recombinant immunogens. Among these, RI-13, RI-20, and RI-31 were selected as the leading candidates. Their protective efficacy was assessed in a zebrafish TB infection model and in BALB/c mice following DNA vaccination. Humoral and cellular immune responses were further evaluated in C57BL/6 mice. Results: RI-13, RI-20, and RI-31 markedly reduced infection-associated pathology and lowered bacterial burden by up to 1.5 log₁₀ in the zebrafish TB infection model, outperforming benchmark antigen combinations, including the Ag85A plus ESAT6/CFP10 cocktail used in the phase III vaccine candidate GamTBvac. In BALB/c mice, DNA vaccination with each construct reduced pulmonary mycobacterial burden by approximately 0.3 log₁₀ and alleviated lung tissue damage. In addition, all three candidates elicited robust humoral and cellular immune responses, with RI-13 showing the strongest overall immunogenicity and inducing a balanced Th1, Th2, and Th17 response profile in C57BL/6 mice. Conclusions: These findings identify RI-13, derived from Rv1174c, as a promising next-generation TB vaccine candidate. More broadly, this study supports the utility of an AI-guided framework for the rational design and preclinical prioritization of novel TB immunogens. 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

Background/Objectives: Epitope-based mRNA vaccines represent a promising strategy for eliciting protective T-cell immunity against SARS-CoV-2 and as well as for non-infectious mRNA-based vaccines. However, how the structural architecture of vaccine constructs (including epitope arrangement, linker composition, signal peptide presence, and the combination of MHC class I and II epitopes) shapes the quality of T-cell responses remains poorly understood. Methods: Ten tandem minigene mRNA constructs (Cons1–10) encoding different combinations of MHC class I and class II epitopes from SARS-CoV-2 proteins (S, N, M, ORF3a) were designed, encapsulated in lipid nanoparticles, and administered to C57BL/6 mice. Immunogenicity was assessed by cytokine profiling (IFN-γ, IL-2, IL-4, IL-10) and T-cell proliferation assays. Protective efficacy was evaluated in K18-hACE2 transgenic mice challenged with SARS-CoV-2. Results: Constructs lacking a signal peptide and enriched in MHC class I-restricted epitopes induced robust Th1 responses and strong CD8⁺ T-cell proliferation, achieving up to 66% survival following lethal challenge. In contrast, constructs associated with elevated IL-10 and IL-4 production conferred limited protection (11–33%), consistent with functional skewing towards regulatory or Th2-associated immune profiles. Conclusions: These findings establish a direct link between construct design parameters and T-cell polarization quality, and provide a rational framework for next-generation epitope-based mRNA vaccine development. Full article

Neoantigen vaccines have revitalized cancer vaccination by targeting tumor-specific mutant epitopes largely absent from central tolerance. Yet, clinical benefits remain inconsistent, in part because conventional vaccine platforms often do not reliably deliver antigens within an inflammatory tumor context, struggle to overcome immunosuppressive tumor microenvironments, and may not rapidly adapt to tumor heterogeneity and evolution. Oncolytic viruses (OVs) provide a mechanistically distinct route to “vaccinate in situ” by coupling tumor-selective infection and immunogenic cancer cell death with local innate immune activation, antigen release, and remodeling of the tumor microenvironment. In parallel, advances in sequencing, neoantigen prediction (e.g., updated NetMHCpan and MHCflurry tools as of 2025), and antigen presentation validation have enabled rational selection of patient-specific targets. At the same time, modern OV engineering supports insertion of neoantigen payloads and immune-modulatory transgenes. Here, we summarized principles that underpin neoantigen-encoded OVs as personalized cancer vaccines, emphasizing how OV adjuvanticity and antigenicity interact to drive priming, epitope spreading, and durable systemic immunity. We discussed major OV platforms with respect to payload capacity, expression control, manufacturability, and clinical track records, including lessons learned from approved or late-stage OVs such as talimogene laherparepvec (T-VEC) and teserpaturev/G47Δ. We also discussed design choices for encoding neoantigens (polyepitope strings, minigenes, long peptides; class I/II balancing), prioritizing translational biomarkers and immune-monitoring strategies, and outlining regulatory and GMP considerations for “platform-plus-variable insert” products. Finally, we propose a pragmatic clinical workflow for rapid personalization to maximize therapeutic index. Tightly integrating neoantigen science with immunovirotherapy, including recent 2025 preclinical advances like oncolytic adenovirus neoantigen delivery sensitizing low-TMB tumors to PD-1 blockade, could enable next-generation personalized cancer vaccines capable of converting “cold” tumors into responsive, systemically controlled disease. Full article

Background: Tuberculosis (TB) remains a pressing global health crisis. The inadequate efficacy of the BCG vaccine against adult pulmonary TB underscores the urgent need for novel, effective vaccines. This study aimed to design a novel mRNA vaccine candidate against TB using a rational immunoinformatics approach. Methods: From 13 antigens, >12,000 epitopes were filtered to select 60 optimal peptides (36 CTL, 16 HTL, 8 B-cell), assembled into 25 scaffolds with 49 TLR2/4 agonist configurations. EP9158H underwent structural modeling, 100 ns molecular dynamics, docking, immune simulation, RNAfold, and conservation analysis across 76 strains. Results: EP9158H, encoding 15 CTL, 9 HTL, and 8 B-cell epitopes flanked by TLR2 agonist ESAT-6 and TLR4 agonist HBHA, emerged as the optimal candidate. All 32 constituent epitopes showed >81% conservation, with 81.25% exhibiting perfect identity across MTBC lineages. The scaffold demonstrated high solubility (0.531), broad population coverage (73.76% MHC-I, 88.91% MHC-II), optimal TLR2/4 docking scores (−1359.7 and −1348.3), and robust structural stability (ProSA Z-score −6.18; RMSD 22–27 Å). Immune simulation predicted strong Th1-biased T-cell responses and high levels of antibody titers. RNAfold analysis revealed stable mRNA secondary structures (MFE −1127.5 kcal/mol) supporting efficient translation. Conclusions: EP9158H integrates broad epitope coverage, dual TLR agonism, and validated stability. Compared to single-antigen vaccines, it offers superior strain coverage, enhanced innate activation, and mRNA advantages for CTL induction, warranting experimental validation. Full article

Dengue virus remains a major global health threat due to the lack of a safe and broadly effective vaccine. Traditional antibody-based vaccines often show limited protection and can exacerbate disease severity in individuals without prior exposure. A new generation of T-cell epitope-based vaccines offers a promising and safer approach by activating the cellular arm of the immune system to complement antibody responses. Instead of targeting only surface structural proteins, these vaccines focus on highly conserved peptide regions within non-structural proteins, particularly NS3 and NS5, that are shared across all four dengue virus serotypes. Peptides such as DTTPFGQQR, KPGTSGSPI, and MYFHRRDLRL have been identified as potent immunogenic targets capable of inducing strong cytotoxic and helper T-cell responses, promoting viral clearance and long-term immune memory. Advanced immunoinformatic enables precise prediction and selection of epitopes with high binding affinity to human leukocyte antigens and broad cross-serotype conservation. These peptides can be integrated into next-generation vaccine delivery systems, including messenger RNA and nanoparticle platforms, which enhance antigen presentation, improve molecular stability, and reduce the risk of antibody-dependent disease enhancement. Together, this integrative design represents a rational path toward a safer, cross-protective, and durable dengue vaccine that closely mimics the balanced cellular and humoral immunity observed after natural infection, offering renewed hope for effective global dengue prevention. Full article

Peptide nanofibers (PNFs) have emerged as versatile platforms for delivering therapeutic agents due to their biocompatibility, tunable characteristics, and ability to form well-ordered nanostructures. The primary goal of this review is to elaborate on the key features of common PNF fabrication strategies, including both spontaneous and non-spontaneous methods, while exploring how the amino acid sequences of these peptides influence their secondary structure and fiber formation. Additionally, we have compiled studies on PNFs that investigate various delivery approaches, such as systemic delivery, localized delivery, controlled delivery, stimuli-responsive delivery, and targeted delivery. This analysis aims to guide researchers in selecting the most suitable fabrication strategy for specific delivery applications and provide insights into choosing optimal amino acids for rational peptide design. We also focused on the applications of PNFs in delivering various therapeutic agents, including drugs, functional peptides, diagnostic and imaging agents, genes, viral vectors, and vaccines, demonstrating their significant potential in biomedical applications. The synergy between nanofiber fabrication strategies and peptide chemistries offers new avenues for advancing therapeutic products. Overall, this review serves as an important reference for the design and development of advanced PNFs for the effective delivery of various therapeutic agents. Full article

Avian influenza A viruses (IAVs) pose a persistent threat to the poultry industry, causing substantial economic losses. Although traditional vaccines have helped reduce the disease burden, they typically rely on multivalent antigens, emphasize humoral immunity, and require intensive production. This study aimed to establish a genetically matched host–cell system to evaluate antigen-specific immune responses and identify conserved CD8+ T cell epitopes in avian influenza viruses. To this end, we developed an MHC class I genotype (B21)-matched host (Lohmann VALO SPF chicken) and cell vector (DF-1 cell line) model. DF-1 cells were engineered to express the hemagglutinin (HA) gene of clade 2.3.4.4b H5N1 either transiently or stably, and to stably express the matrix 1 (M1) and nucleoprotein (NP) genes of A/chicken/South Korea/SL20/2020 (H9N2, Y280-lineage). Following prime-boost immunization with HA-expressing DF-1 cells, only live cells induced strong hemagglutination inhibition (HI) and virus-neutralizing (VN) antibody titers in haplotype-matched chickens. Importantly, immunization with DF-1 cells transiently expressing NP induced stronger IFN-γ production than those expressing M1, demonstrating the platform’s potential for differentiating antigen-specific cellular responses. CD8+ T cell epitope mapping by mass spectrometry identified one distinct MHC class I-bound peptide from each of the HA-, M1-, and NP-expressing DF-1 cell lines. Notably, the identified HA epitope was conserved in 97.6% of H5-subtype IAVs, and the NP epitope in 98.5% of pan-subtype IAVs. These findings highlight the platform’s utility for antigen dissection and rational vaccine design. While limited by MHC compatibility, this approach enables identification of naturally presented epitopes and provides insight into conserved, functionally constrained viral targets. Full article

Viruses use a range of sophisticated strategies to evade detection by cytotoxic T-lymphocytes (CTLs) within host cells. Beyond elaborating dedicated viral proteins that disrupt the MHC class I antigen-presentation machinery, some viruses possess intrinsic, cis-acting genome-encoded elements that interfere with antigen processing and display. These protein features, including G-quadruplex motifs, repetitive peptide sequences, and rare-codon usage, counterintuitively limit production of proteins critical to virus survival, particularly during latency. By slowing viral protein synthesis, these features reduce antigen production and proteosomal degradation, ultimately limiting the generation of peptides for MHC I presentation. These built-in evasion tactics enable viruses to remain “invisible” to CTLs during latency. While these primary sequence intrinsic immune evasion (PSI) mechanisms are well-described in select herpesviruses, emerging evidence suggests that they may also play a critical role in RNA viruses. How these proteins are made, rather than what they functionally target, determines their immune evasion properties. Understanding PSI mechanisms could rationally inform the design of engineered viral antigens with altered or removed evasion elements to restore antigen CTL priming and activation. Such vaccine strategies have the potential to enhance immune recognition, improve clearance of chronically infected cells, and contribute to the treatment of persistent viral infections and virus-associated cancers. Full article

Signal peptides (SPs) are short amino acid sequences located at the N-terminus of nascent proteins and are widely present across various life forms. They play crucial roles in protein synthesis, transmembrane transport, and intracellular signal transduction. With the rapid advancement of bioinformatics, studies have revealed that the functions of SPs are far more complex than previously understood. In recombinant protein expression systems, the rational design and optimization of SPs are essential for enhancing the expression efficiency and secretion level of exogenous proteins. Meanwhile, the application value of SPs in vaccine development has attracted increasing attention. This review summarizes the structural characteristics, functional mechanisms, and applications of SPs in recombinant protein production and SP-based vaccines. It also discusses their biological roles, the significance of engineering optimization strategies, and the current challenges, aiming to provide theoretical support and practical guidance for improving recombinant protein yield and advancing SP-based vaccine development. Full article

Toll-like receptor 2 (TLR2) signaling is a pivotal component of immune system activation, and it is closely linked to the lipidation of bacterial proteins. This lipidation is guided by bacterial signal peptides (SPs), which ensure the precise targeting and membrane anchoring of these proteins. The lipidation process is essential for TLR2 recognition and the activation of robust immune responses, positioning lipidated bacterial proteins as potent immunomodulators and adjuvants for vaccines against bacterial-, viral-, and cancer-related antigens. The structural diversity and cleavage pathways of bacterial SPs are critical in determining lipidation efficiency and protein localization, influencing their immunogenic potential. Recent advances in bioinformatics have significantly improved the prediction of SP structures and cleavage sites, facilitating the rational design of recombinant lipoproteins optimized for immune activation. Moreover, the use of SP-containing lipobox motifs, as adjuvants to lipidate heterologous proteins, has expanded the potential of vaccines targeting a broad range of pathogens. However, challenges persist in expressing lipidated proteins, particularly within heterologous systems. These challenges can be addressed by optimizing expression systems, such as engineering E. coli strains for enhanced lipidation. Thus, lipoprotein signal peptides (SPs) demonstrate remarkable versatility as adjuvants in vaccine development, diagnostics, and immune therapeutics, highlighting their essential role in advancing immune-based strategies to combat diverse pathogens. Full article