Search Results (189)

Angiostrongyliasis, the primary cause of eosinophilic meningitis, represents an emerging disease caused by Angiostrongylus cantonensis larvae, inadvertently transmitted to humans. The diagnosis of human angiostrongyliasis relies on epidemiological features, clinical symptoms, medical history, and laboratory findings, notably hyper eosinophilia in blood and cerebrospinal fluid. Consequently, accurate diagnosis is challenging and prone to confusion with other parasitic diseases. The quest for an early, rapid, and specific diagnostic test for angiostrongyliasis persists, driven by the imperative for enhanced test specificity. This study focused on mapping IgM epitopes on galectin-1 (Gal-1) and galectin-2 (Gal-2) proteins derived from A. cantonensis. The specificity of the epitopes was assessed using database homology analysis. After selecting specific epitopes, researchers chemically synthesized 12 individual multi-antigen peptides (MAPs4) and one chimeric polypeptide that is 65 amino acids long. The effectiveness of these synthesized peptides was subsequently evaluated using enzyme-linked immunoassay (ELISA). A total of twelve unique IgM epitopes were discovered; five were linked to Gal-1, while seven were linked to Gal-2. An ELISA-peptide method confirmed the twelve epitopes, and then the chimeric polypeptide was employed as an antigen to coat ELISA plates. This setup was evaluated with patients’ sera to diagnose strongyloidiasis in vitro. This study provides a comprehensive representation of the IgM epitopes of Gal-1 and Gal-2 from A. cantonensis. ELISA data utilizing the chimeric polypeptide demonstrate that the selected sequences hold promise for the development of a specific immunological assay tailored for the acute diagnosis of angiostrongyliasis infections. Full article

Brucellosis is a globally prevalent zoonotic disease affecting both humans and animals. Its nonspecific clinical manifestations often complicate diagnosis, underscoring the need for reliable laboratory confirmation. Traditional serological assays, though widely used, suffer from limitations such as inconsistent sensitivity and false-positive results. To address these challenges, this study mapped IgM and IgG epitopes of the Brucella Omp-2a protein using sera from infected patients. Epitope identification was performed through SPOT synthesis on cellulose membranes, followed by assessment of potential cross-reactivity using peptide database analysis and ELISA validation. Three major IgM and seven IgG linear B-cell epitopes were identified, six of which demonstrated strong reactivity in peptide-ELISA. Importantly, no significant cross-reactivity with proteins from other human pathogens was detected. Two chimeric multi-epitope peptides, composed of 50 and 60 amino acids and integrating Brucella-specific IgM and IgG epitopes, exhibited excellent diagnostic performance in ELISA, achieving near 100% sensitivity and specificity. These findings support the potential of synthetic peptides as reliable and cost-effective alternatives to native antigens in serological assays. Further validation in larger, geographically diverse cohorts will be essential to confirm their diagnostic robustness and facilitate their integration into routine brucellosis diagnostics. Full article

The hybrid approach remains a compelling strategy for designing molecules that combine enhanced biological activity with a favorable safety profile. Marine peptides, in particular, have attracted significant attention due to their well-documented broad spectrum of biological activities. Peptides derived from rays have been recognized for their diverse biological activities. Notably, physicochemical properties of these peptides support practical application without requiring further refinement of the mature molecule or specialized formulations. In this study, we present two new chimeric peptides, PK01# and PK02#, which incorporate an opioid pharmacophore linked to a short amino acid sequence derived from the skate Raja porosa. Those compounds interact with the opioidergic system, specifically targeting the mu-opioid receptor (MOR). Furthermore, the compounds were evaluated for their effects on cancer cell viability through in vitro MTT assays (as an exploratory endpoint) and for their binding compatibility with EGFR via in silico docking. Both compounds showed limited effects on cell viability in HeLa, SAS, and PANC-1 cells, while PK02# induced a minor reduction in metabolic activity in glioblastoma cells without reaching IC50 values or significant cytotoxic thresholds. Interestingly, the structures of these hybrid compounds offer valuable insights into the role of phenylalanine residues within their sequences, which appear to be critical for both biological activity and receptor interaction. Moreover, these findings may support future structural optimization of peptide hybrids focused on receptor modulation and biological profiling. Full article

Botulinum neurotoxin injections are used off-label to treat chronic pain, but their efficacy is limited and paralytic effects restrict clinical utility in these applications. Here, we investigated whether combining the light chain and translocation domains of botulinum neurotoxin A (BoNT/A) with the GM1-binding B subunit of cholera toxin would be beneficial in silencing pain-associated sensory neurons. Chimeric ChoBot was assembled via a coiled-coil linking technology and was shown to retain the enzymatic activity of BoNT/A in vitro and in vivo. In cultured dorsal root ganglion neurons, ChoBot cleaved SNAP25 in a calcitonin gene-related peptide (CGRP)-rich subpopulation of sensory neurons, resulting in marked inhibition of CGRP release. ChoBot had a lesser effect on the compound muscle action potentials of the rat gastrocnemius muscle than BoNT/A following subcutaneous injections. In rat models of pain, including chemotherapy-induced peripheral neuropathy, intraplantar administration of ChoBot significantly attenuated mechanical allodynia. Immunohistochemical analysis confirmed SNAP25 cleavage in NF200- and CGRP-expressing sensory fibres in the epidermis following a single injection. ChoBot also mediated SNAP25 cleavage in human neuroblastoma cells in culture. Together, these findings indicate that ChoBot enables a silencing of pain-associated sensory pathways, providing a new strategy for the development of new long-lasting analgesics for chronic pain. Full article

Anticancer peptides (ACPs) offer a promising alternative to conventional chemotherapy but face challenges, including poor selectivity, limited tumor penetration, low cellular uptake, and rapid degradation in serum. To address these barriers, we developed synthetic mRNAs encoding chimeric ACPs designed for enhanced intracellular delivery and activity. mRNAs for constructs SAK6L9AS(1X), SAK6L9AS(4X), and WTAS-K6L9(4X) were transcribed in vitro and tested against 4T1 breast cancer cells. Cytotoxicity was assessed by cell confluence and MTT assays, while apoptosis was evaluated using caspase 3/7 activation, PI staining, and Annexin V flow cytometry. Our results demonstrate that all SAK6L9AS variants induced robust apoptosis and cellular toxicity in 4T1 cells. Importantly, this work provides the first demonstration of intracellular expression of an mRNA-encoded ACP fused to a cell-penetrating peptide, thereby validating a modular platform for RNA-based delivery of anticancer agents. This study highlights the feasibility of mRNA-encoded peptide therapeutics as a scalable and customizable strategy for cancer treatment. By combining the advantages of mRNA delivery with rational peptide design, ACP chimeras can be expressed directly inside tumor cells, overcoming the limitations of exogenous peptide administration. Our findings support further development of synthetic mRNA therapeutics to generate potent, selective anticancer peptides with reduced systemic toxicity and improved translational potential. Full article

Leishmaniases are infections caused by Leishmania parasites and transmitted through the bite of infected female Phlebotomus (Old World) and Lutzomyia (New World) sandflies. The disease disproportionately affects marginalized communities with limited healthcare access. With no approved human vaccines available, leishmaniasis treatment and prevention depend heavily on chemotherapeutics that face growing drug resistance challenges alongside toxicity concerns. The development of safe, effective and affordable vaccines against human leishmaniasis remains a global health priority for disease control and elimination, mostly in resource-limited settings. This review synthesizes progress in leishmaniasis vaccine platforms including live-attenuated parasites, whole-killed parasites, DNA, protein subunit, peptide-based and chimeric/multiepitope vaccines and their homogenous and heterogenous efficacy. Live-attenuated and whole-parasite vaccines have been accounted to elicit robust cellular immunity but pose safety risks, particularly in immunocompromised hosts. While both second- and third-generation vaccines exemplified by LEISH-F1/F3 polyproteins, elicit strong Th1-biased T cell responses in preclinical models, their efficacy in humans remains limited. However, the highlighted collective efforts are pivotal in steering the rational development of future research using various formulations for multiple management of leishmaniasis through cross-protection. Furthermore, emerging strategies including mRNA platforms, nanoparticle delivery, reverse vaccinology, and immunoinformatics offer promising avenues for accelerating vaccine discovery and advancing the development of novel and effective human vaccines. Full article

Background: Tumor neoantigens are key targets for personalized vaccines and T-cell therapies, yet most pipelines focus on neoantigens derived from SNV/small indel and often yield a limited number of high-quality candidates. SVs are prevalent in tumors and can generate novel chimeric sequences and neopeptides, making them a promising additional source of neoantigens. However, SV-derived neoantigen prediction remains challenging due to breakpoint uncertainty, isoform-dependent coding inference, and limited integration of multi-dimensional evidence and reproducibility. Methods: We developed SVNeoPP (Structural Variant Neoantigen Prediction and Prioritization), an end-to-end workflow for SV-derived neoantigen analysis. SVNeoPP takes WGS and RNA-seq as inputs, performs SV calling and annotation, and reconstructs altered transcripts and coding sequences in a traceable, isoform-aware manner to generate candidate peptides. Candidates are prescreened by integrating antigen-processing features with HLA binding prediction, and then hierarchically filtered and prioritized based on transcript expression, LC–MS/MS proteomics evidence, immunogenicity predictions, and sequence similarity to experimentally validated neoantigen databases. SVNeoPP is implemented in Snakemake to enable modular extension, checkpoint-based restarts, and end-to-end reproducibility. Results: Using a hepatocellular carcinoma (HCC) multi-omics dataset as a proof of concept, we demonstrated the performance of SVNeoPP and obtained a high-priority shortlist of candidate peptides. Compared with other methods, SVNeoPP substantially expanded the candidate search space for SV-derived neoantigens and showed more favorable distributions of antigen-processing and HLA binding features. Conclusions: SVNeoPP provides a reusable, traceable, and interpretable multi-dimensional evidence-driven framework for SV-derived neoantigens. As a complementary module to SNV/small-indel pipelines, it broadens the neoantigen candidate repertoire and generates ranked candidates with interpretable evidence to facilitate downstream prioritization and decision-making. Full article

Background/Objectives: Eliciting robust immune responses against the hepatitis B virus (HBV) through therapeutic vaccination holds promise for curing chronic hepatitis B. We previously developed the heterologous protein prime/viral vector boost clinical vaccine candidate, TherVacB. Here, we evaluated a replication-competent chimeric vesicular stomatitis virus vector (VSV-GP) as an alternative viral vector boost vaccine. Methods: A recombinant VSV-GP vector co-expressing HBV surface and core antigens (VSV-GP-HBs/c) was generated and characterized for antigen expression. Its immunogenicity, antiviral efficacy, and durability were assessed in HBV-naïve and HBV-carrier mice, using protein primed, viral vector-primed, and multi-viral vector boost regimens. Results: VSV-GP-HBs/c efficiently expressed both HBV antigens in vitro. A single immunization with VSV-GP-HBs/c induced only weak HBV-specific immune responses in vivo. Replacing protein priming with VSV-GP-HBs/c resulted in modest immune activation and limited antiviral effects in HBV-carrier mice. In contrast, substituting the modified vaccinia virus Ankara (MVA)-HBs/c boost in the TherVacB regimen with VSV-GP-HBs/c elicited robust HBV-specific antibody responses and strong CD4 and CD8 T-cell immunity, assessed by intracellular IFN-γ staining after peptide stimulation. This regimen achieved a substantial reduction in serum HBsAg levels, numbers of HBV-positive hepatocytes, and intrahepatic HBV-DNA, with antiviral efficacy comparable to that of the classical TherVacB regimen. Notably, a second viral vector boost did not enhance HBV-specific immunity or antiviral efficacy; instead, it promoted dominant vector-specific CD8 T-cell responses. Long-term analyses performed 10 weeks after the last vaccination further demonstrated that a single protein-prime/VSV-GP-HBs/c boost was sufficient to achieve sustained antiviral control. Conclusions: These findings identify VSV-GP-HBs/c as an effective boost vector for therapeutic hepatitis B vaccination and establish protein priming followed by a single viral vector boost as an optimal strategy for sustained antiviral immunity. Full article

Mass spectrometry-based analysis of post-translational modifications (PTMs) is a key strategy for characterizing protein regulation and identifying disease-associated targets, with endogenous PTMs serving as biomarkers for disease diagnosis and therapeutic response. More recently, chemical proteomic strategies have adapted PTM-focused workflows to measure engagement of covalent and photoactivatable small-molecule probes, expanding the scope of ligand discovery for these disease-associated targets. This review provides an overview of mass spectrometry-based PTM analysis workflows, including LC–MS/MS acquisition and post-acquisition data processing, with an emphasis on how modification-specific physicochemical properties influence PTM detection and identification. Common analytical challenges that limit PTM identification, including variable MS/MS fragmentation behavior and modification site localization, are discussed using modifications such as phosphorylation and photoaffinity labeling probe adducts as representative examples. Recent advances in acquisition strategies and computational tools that improve spectral quality and confidence in PTM assignment are also summarized. Additionally, approaches for the analytical validation of modification events, such as metabolic labeling strategies, are described. Together, this review outlines key considerations, capabilities, and limitations of MS-based PTM profiling and provides a framework for interpreting PTM datasets to support their effective integration into downstream biochemical and disease target validation studies. Full article

Background/Objectives: The oncoprotein EWS::FLI1 is a chimeric transcription factor that aberrantly brings transcriptional deregulation relevant to Ewing sarcoma. It is also regarded as a therapeutic target for suppressing oncogenic progression, but the inhibition and clearance of the EWS::FLI1 oncoprotein remain a challenge. Methods: We apply a polyglutamine (polyQ) fusion strategy to directly target EWS::FLI1 in suppression of its transcriptional malfunction in A673 cells derived from Ewing sarcoma. Based on the template of the N-terminal fragment of polyQ-expanded ataxin-7 (Atx7_93Q-N172) and the homologous peptides of EWS::FLI1, we have designed and constructed three polyQ fusion proteins, namely Atx7_93Q-N172-SYGQ1, Atx7_93Q-N172-SYGQ2, and Atx7_93Q-N172-LCD. Results: Supernatant/pellet fractionation and immunofluorescence imaging reveal that the polyQ fusion proteins co-precipitate and co-localize with EWS::FLI1 in A673 cells, indicating that the polyQ fusions we have designed can sequester endogenous EWS::FLI1 into insoluble aggregates and reduce its cellular availability. Moreover, these polyQ fusions, especially Atx7_93Q-N172-LCD, alter the expression of EWS::FLI1 downstream genes, with an increase in P21 (CDKN1A) and a decrease in c-Myc. Conclusions: These results demonstrate that the engineered polyQ fusions entrap endogenous EWS::FLI1 protein into aggregates and reduce its soluble fraction in Ewing sarcoma cells. This study provides an alternative potential for treating Ewing sarcoma and other tumors by directly targeting the oncogenic proteins in the future. Full article

Efficient in vitro regeneration remains a major constraint in the genetic transformation, genome editing, and molecular breeding of wheat (Triticum aestivum L.), largely due to strong genotype-dependent recalcitrance and limited activation of developmental programs required for somatic embryogenesis. Plant regeneration relies on extensive transcriptional reprogramming and epigenetic remodeling orchestrated by morphogenic regulators that modulate meristem identity, as well as cellular pluri- and totipotency. In this review, we synthesize current molecular knowledge on key transcription factors (BBM, WUS/WUS2, GRF-GIF, WOX, LAX1, SERK, WIND1/ERF115) and signaling peptides (CLE/CLV-WUS module, phytosulfokine/PSK) that regulate embryogenic competence in monocot cereals, with emphasis on their orthologs and functional relevance in wheat. We highlight how controlled expression of these morphogenic genes, promoter engineering, and transient or excisable induction systems can significantly enhance regeneration capacity, reduce chimerism in CRISPR-Cas-edited plants, and facilitate genotype-independent transformation. We also discuss epigenetic and metabolic constraints underlying wheat recalcitrance and their potential modulation to improve culture responsiveness. By integrating evidence from wheat, rice, maize, and barley, we outline conserved gene-regulatory networks that reinitiate totipotency and propose strategies to accelerate doubled haploid production and speed-breeding pipelines. Collectively, morphogenic factors emerge as central molecular tools for overcoming regeneration bottlenecks and enabling next-generation wheat improvement. The objective of this review is to synthesize and critically evaluate current molecular knowledge on morphogenic regulators controlling in vitro regeneration in wheat (Triticum aestivum L.), with particular emphasis on their roles in genetic transformation and genome editing. Full article

Background: Porcine circovirus type 2 (PCV2) remains one of the most important pathogens that infects swine, causing considerable economic losses worldwide. PCV2 vaccines are commercially available, and the development of experimental vaccines that could confer better protection against emerging genotypes is underway. The expression of virus-like particles (VLPs) carrying different PCV2 capsid (Cap) peptides in E. coli was recently reported. These chimeric particles were adjuvated with an oil-in-water emulsion with polymer and induced different titers of serum IgG in BALB/c mice after a single subcutaneous injection. The aim of this study was to assess the immune response and protective efficacy elicited by VLPs carrying the PCV2b Cap carboxy-terminal peptide in the target species. Methods: Domestic pigs (Sus scrofa domesticus) were immunized intramuscularly with 25 μg of adjuvated chimeric VLPs on days 0 and 14 and challenged on day 28 with a PCV2b Mexican isolate. PCV2 peptide-specific IgG seroconversion, serum cytokines, viral load in nasal swabs and organs, and histopathological score were determined. Results: IgG levels peaked 28 days post-immunization. Interleukin-12 and -18 and interferon-gamma increased 21 days after immunization. In addition, genomic material of PCV2 was detected in nasal swabs from one specimen on day 7, two specimens on day 14, and two specimens on day 21 following viral challenge. Finally, histological lesions were not less severe in immunized specimens compared to non-vaccinated/challenged specimens. Conclusions: These results suggest that immunization with chimeric VLPs could contribute to controlling viral shedding in pig herds where a PCV2b genotype is most prevalent. Full article

Cutaneous melanoma is an extremely dangerous tumor disease with poor prognosis at advanced stages. Accounting for a small percentage of all skin tumors, malignant melanoma leads the mortality rate in this group of cancers. Clearly, the search for new drugs and therapeutic approaches for the treatment of cutaneous melanoma is a highly pressing issue in modern medicine. In this study, novel recombinant proteins with anti-melanoma activity, called RGD-apoptins, were produced in an E. coli expression system, and their properties were evaluated in human cell models. These chimeric proteins consist of two parts, each tumor-specific. One part of the chimeric molecule is the RGD peptide, which binds to αVβ3 integrins widely expressed on the surface of malignant melanocytes. The other part is the viral protein apoptin, known to induce programmed cell death in tumor cells but not in normal cells. This molecular design aims to enhance the specificity of potential therapeutic agent toward malignant melanoma cells while reducing cytolytic effects on healthy tissue. In a resazurin assay, RGD-apoptins decreased the viability of MeWo human melanoma cells and did not affect the viability of HaCaT human keratinocyte cell line and primary skin fibroblasts. Using an annexin V assay, we confirmed that malignant melanocytes death occurs via apoptosis. Transcriptomic analysis allowed us to dynamically evaluate the spectrum of differentially expressed genes 24 and 48 h after treating melanoma cells with recombinant RGD-apoptin. Full article

Antimicrobial peptides (AMPs), evolutionarily conserved components of the immune system, have attracted considerable attention as promising therapeutic candidates. Derived from diverse organisms, AMPs represent a heterogeneous class of molecules, typically cationic, which facilitates their initial electrostatic interaction with anionic microbial membranes. Unlike conventional single-target antibiotics, AMPs utilize rapid, multi-target mechanisms, primarily physical membrane disruption, which results in a significantly lower incidence of resistance emergence. Their broad-spectrum antimicrobial activity, capacity to modulate host immunity, and unique mechanisms of action make them inherently less susceptible to resistance compared with traditional antibiotics. Despite these advantages, the clinical translation of natural AMPs remains limited by several challenges, including poor in vivo stability, and potential cytotoxicity. Bioengineering technology offers innovative solutions to these limitations of AMPs. Two techniques have demonstrated promise: (i) a chimeric recombinant of AMPs with stable scaffold, such as human serum albumin and antibody Fc domain and (ii) chemical modification approaches, such as lipidation. This review provides a comprehensive overview of AMPs, highlighting their origins, structures, and mechanisms of antimicrobial activity, followed by recent advances in bioengineering platforms designed to overcome their therapeutic limitations. By integrating natural AMPs with bioengineering and nanotechnologies, AMPs may be developed into next-generation antibiotics. Full article