Search Results (5,171)

Tetanus is a zoonotic disease posing significant threats to both humans and animals, particularly horses, sheep, and ruminants. Current antitoxin therapies rely on animal-derived immunoglobulins, presenting challenges including animal welfare concerns, pathogen contamination risks, and manufacturing complexity. Alpaca-derived nanobodies (VHH) are promising alternatives owing to their high antigen-binding affinity, thermostability, and potential for microbial production. We developed highly active trivalent VHH antibodies (tVHH) that target multiple epitopes of tetanus neurotoxin (TeNT). Following alpaca immunization with tetanus toxoid, 41 VHH clones were isolated using phage display. Six VHH clones were selected through in vivo neutralization assays, from which three clones of VHH (8, 11, 36) were selected to construct tVHH-8/11/36 and tVHH-8/36/11. Using an improved 21-day mouse neutralization assay, tVHH-8/11/36 demonstrated exceptional neutralizing activity of approximately 1580 IU/mg against 4000 LD₅₀ of toxin, substantially exceeding current human and veterinary anti-tetanus immunoglobulin preparations. Surface plasmon resonance and ELISA confirmed that each VHH recognizes different TeNT domains, producing synergistic neutralizing effects through multimerization. Since antitoxin therapy challenges are common to both animals and humans, this tVHH technology supports One Health by providing a unified therapeutic platform applicable across species through sustainable microbial production. Full article

Gastrointestinal nematode (GIN) infections are the most prevalent parasitic diseases in grazing sheep worldwide, causing significant productivity losses, high mortality and, as a result, economic losses and emerging animal welfare concerns. Conventional control strategies, primarily relying on anthelmintic treatments, face limitations due to rising drug resistance and environmental concerns, underscoring the need for sustainable alternatives. Selective breeding for host genetic resistance has emerged as a promising strategy, while recent advances in transcriptomics and integrative omics research are providing deeper insights into the immune pathways and molecular and genetic mechanisms that underpin host–parasite interactions. This review summarizes current evidence on transcriptomic signatures associated with resistance and susceptibility to H. contortus and T. circumcincta GIN infections, highlighting candidate genes, functional genetic markers, key immune pathways, and regulatory networks. Furthermore, we discuss how other omics approaches, including genomics, proteomics, metabolomics, microbiome, and multi-omics integrations, provide perspectives that enhance the understanding of the complexity of the GIN resistance trait. Transcriptomic studies, particularly using RNA-Sequencing technology, have revealed differential gene expression, functional genetic variants, such as SNPs and INDELs, in expressed regions and splice junctions, and regulatory long non-coding RNAs that distinguish resistance from susceptible sheep, highlighting pathways related to Th2 immunity, antigen presentation, tissue repair, and stress signaling. Genomic analyses have identified SNPs, QTL, and candidate genes linked to immune regulation and parasite resistance. Proteomic and metabolomic profiling further elucidates breed- and tissue-specific alterations in protein abundance and metabolic pathways, while microbiome studies demonstrate distinct microbial signatures in resistant sheep, suggesting a role in modulating host immunity. In conclusion, emerging multi-omics approaches and their integration strategies provide a comprehensive framework for understanding the complex host–parasite interactions that govern GIN resistance, offering potential candidate biomarkers for genomic selection and breeding programs aimed at developing sustainable, parasite-resistant sheep populations. Full article

Autoimmune type 1 diabetes (T1D) results from the failure of the physiologic regulatory mechanisms that are designed to maintain immune tolerance to pancreatic beta cells. Consequently, the design of strategies to restore tolerance to beta cell antigens is an attractive objective of translational research. We have designed ultrasmall nanoparticles (NPs) loaded with a proinsulin (PI) fusion protein and an agonist for the aryl hydrocarbon receptor (AhR), a transcription factor promoting tolerance induction by different immune cells. We report that a 4 week-treatment with these NPs in non-obese diabetic (NOD) mice starting at disease onset induces temporary and sometimes durable disease remission. Mechanistically, short-term NP treatment induces a rapid depletion of islet infiltrates with a dramatic reduction in the number of CD8⁺ T cells and dendritic cells. This is accompanied by the emergence of B lymphocytes producing IL-10. In the rare mice that undergo durable disease remission, the disappearance of islet infiltrates is associated with the emergence of Foxp3⁺ CD4⁺ regulatory T cells, IFN-γ-producing memory T cells in the spleen, and draining lymph nodes (LNs). We conclude that treatment with these NPs could be of interest in the treatment of recent-onset autoimmune diabetes, but is unlikely to be sufficient for the induction of long-term remission as a stand-alone therapy. Full article

Background/Objectives: Inadequate characterization of protective antigens poses a significant challenge to the development of vaccines for African swine fever (ASF), particularly for antigen-dependent formulations such as subunit, mRNA, and recombinant viral vector vaccines. To address this, we aimed to screen African swine fever virus (ASFV) antigens and enhance their immunogenicity using a nanoparticle delivery platform. Methods: Here, six ASFV antigens (p30, p54, pE120R, pH124R, pE184L, and CD2v) were purified and used to immunize pigs individually. The effects of antibodies induced by these six antigens on ASFV replication or hemadsorption was evaluated in primary porcine alveolar macrophages (PAMs). These six antigens were, respectively, conjugated to ferritin via SpyTag/SpyCatcher to prepare six ferritin nanoparticles. A cocktail of the six mixed antigens or a cocktail of the six mixed nanoparticles was used to immunize pigs separately, and the differences in induced humoral and cellular immune responses were compared. Results: Antibodies generated against p30, p54, pE120R, pH124R, and pE184L in immunized pigs significantly inhibited ASFV replication in PAMs, while anti-CD2v antibodies specifically obstructed the hemadsorption of ASFV. Notably, immunization with a cocktail of these antigen-conjugated nanoparticles elicited a stronger virus-inhibitory antibody response compared to immunization with a cocktail of antigen monomers. Furthermore, nanoparticle immunization induced robust cellular immunity, evidenced by elevated serum IFN-γ, increased numbers of ASFV-specific IFN-γ-secreting cells, and an expanded CD8⁺ T cell population. Conclusions: Our study identifies a set of promising ASFV antigen candidates and demonstrates that ferritin nanoparticle delivery synergistically enhances both humoral and cellular immune responses against ASFV, providing a rational strategy for multi-antigen ASF vaccine design. Full article

Burkholderia pseudomallei complex and B. cepacia complex are two evolutionary distinct clades of pathogens causing human disease. Most vaccine efforts have focused on the former group largely due to their biothreat status and global disease burden. It has been proposed that a vaccine could be developed that simultaneously protects against both groups of Burkholderia by specifically targeting conserved antigens. Only a few studies have set out to identify which antigens may be optimal targets for such a vaccine. We have previously assessed the ability of three highly conserved B. pseudomallei antigens, namely OmpA1, OmpA2, and Pal, coupled to gold nanoparticle vaccines, to protect mice against a homotypic B. pseudomallei challenge. Here, we have expanded our study by demonstrating that antibodies to each of these proteins show varying levels of reactivity to homologues in B. cepacia complex, with OmpA2 antibodies exhibiting the highest cross-reactivity. Remarkably, some nanovaccine immunized mice, particularly those that received OmpA2, produced antibodies that bind Pseudomonas aeruginosa, which harbors distantly related homologous proteins. T cells elicited to Pal and OmpA2 responded to stimulation with B. cepacia complex-derived homologues. Our study supports incorporation of these antigens, particularly OmpA2, for the development of a pan-Burkholderia vaccine. Full article

Chimeric antigen receptor (CAR) T cell therapy has demonstrated clinical success in hematologic malignancies but has limited efficacy in solid tumors due to tumor microenvironment (TME) barriers that impede CAR T cell recognition, infiltration, and sustained function. Traditional 2D assays inadequately recapitulate these constraints, necessitating improved in vitro models. This study validated a 3D tumor spheroid platform using an agarose microwell system to generate uniform B7-H3-positive spheroids from multiple solid tumor cell lines, enabling the evaluation of CAR T cell activity. TME-relevant immune modulation under 3D conditions was analyzed by flow cytometry for B7-H3, MHC I/II, and antigen processing machinery (APM), followed by co-culture with B7-H3 CAR T cells to assess cytotoxicity, spheroid integrity, tumor viability, and CAR T cell activation, exhaustion, and cytokine production. Two human cancer-cell-line-derived spheroids, DU 145 (prostate cancer) and SUM159 (breast cancer), retained B7-H3 expression, while MC38 (mouse colon cancer)-derived spheroids served as a B7-H3 negative control. Under 3D culture conditions, DU 145 and SUM159 spheroids acquire TME-like immune evasion characteristics and specifically downregulated MHC-I and APM (TAP1, TAP2, LMP7) with concurrent upregulation of MHC-II and calreticulin. Co-culture showed effective spheroid infiltration, cytotoxicity, and structural disruption, with infiltrating CAR T cells displaying higher CD4⁺ fraction, activation, exhaustion, effector/terminal differentiation, and IFN-γ/TNF-α production. This 3D platform recapitulates critical TME constraints and provides a cost-effective, feasible preclinical tool to assess CAR T therapies beyond conventional 2D assays. Full article

Early life is a critical window for immune system development, during which the gut microbiome shapes innate immunity, antigen presentation, and adaptive immune maturation. Disruptions in microbial colonization—driven by factors such as cesarean delivery, antibiotic exposure, and formula feeding—deplete beneficial early-life taxa (e.g., Bifidobacterium, Bacteroides, and Enterococcus) and impair key microbial functions, including short-chain fatty acid (SCFA) production by these keystone species, alongside regulatory T cell induction. These dysbiosis patterns are associated with an increased risk of pediatric autoimmune diseases, notably type 1 diabetes, inflammatory bowel disease, celiac disease, and juvenile idiopathic arthritis. This review synthesizes current evidence on how the early-life microbiota influences immune maturation, with potential effects on the development of autoimmune diseases later in life. We specifically focus on human observational and intervention studies, where treatments with probiotics, synbiotics, vaginal microbial transfer, or maternal fecal microbiota transplantations have been shown to partially restore a disrupted microbiome. While restoration of the gut microbiome composition and function is the main reported outcome of these studies, to date, no reports have disclosed direct prevention of autoimmune disease development by targeting the early-life gut microbiome. In this regard, a better understanding of the early-life microbiome–immune axis is essential for developing targeted preventive strategies. Future research must prioritize longitudinal evaluation of autoimmune outcomes after microbiome modulation to reduce the burden of chronic immune-mediated diseases. Full article

Chimeric antigen receptor (CAR)-T cell therapy has emerged as a transformative form of immunotherapy, enabling the precise engineering of T cells to recognize and eliminate pathogenic cells. In hematologic malignancies, CAR-T cells targeting CD19 or B cell maturation antigens have achieved remarkable remission rates and durable responses in patients with otherwise refractory disease. Despite these successes, extending CAR-T cell therapy to solid tumors remains challenging due to antigen heterogeneity, poor T cell infiltration, and the immunosuppressive tumor microenvironment (TME). Beyond oncology, CAR-T cell therapy has also shown promise in autoimmune diseases, where early clinical studies suggest that B cell-directed CAR-T cells can induce sustained remission in conditions such as systemic lupus erythematosus. This review highlights advances in CAR-T cell engineering, including DNA- and mRNA-based platforms for ex vivo and in vivo programming, and discusses emerging strategies to enhance CAR-T cell trafficking, persistence, and resistance to TME. Full article

Although the SARS-CoV-2 pandemic no longer poses a global emergency, the virus continues to diversify and acquire immunoevasive properties. Understanding the molecular pathways that shape SARS-CoV-2 pathogenesis has become essential. In this paper, we summarize the most recent current evidence on how the spike protein structurally evolves, on changes in key non-structural proteins, such as nsp14, and on host factors, such as TMPRSS2 and neuropilin-1. These changes, together, shape viral entry, replication fidelity and interferon antagonism. Given the emerging Omicron variants of SARS-CoV-2, recent articles in the literature, cryo-EM analyses, and artificial intelligence-assisted mutational modeling were analyzed to infer and contextualize mutation-driven mechanisms. It is through these changes that the virus adapts and evolves, such as optimizing angiotensin-converting enzyme binding, modifying antigenic surfaces, and accumulating mutations that affect CD8⁺ T-cell recognition. Multi-omics data studies further support SARS-CoV-2 pathogenesis through convergent evidence linking viral adaptation to host immune and metabolic reprogramming, as occurs in myocarditis, liver injury, and acute kidney injury. By integrating proteomic, transcriptomic, and structural findings, this work presents how the virus persists and dictates disease severity through interferon antagonism (ORF6, ORF9b, and nsp1), adaptive immune evasion, and metabolic rewiring. All these insights underscore the need for next-generation interventions that provide a multidimensional framework for understanding the evolution of SARS-CoV-2 and guiding future antiviral strategies. Full article

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment of relapsed or refractory (r/r) diffuse large B-cell lymphoma (DLBCL); however, a significant proportion of patients fail to achieve a durable response, underscoring the need for reliable predictive biomarkers. We characterize T-lymphocyte subpopulations in apheresis samples from 23 r/r large B-cell lymphoma (LBCL) patients who received axicabtagene ciloleucel (axi-cel) to identify pre-treatment cell biomarkers associated with CAR T-cell kinetics and clinical outcomes. Immunophenotyping of T-cells within fresh apheresis samples and monitoring of circulating CAR T-cells were performed by multiparametric flow cytometry. The median peak CAR T-cell count was 45.2 CAR T-cells/mL. Strong CAR-T expanders (≥45.2 CAR T-cells/mL) exhibited higher values of both CD4⁺ (p = 0.011) and CD8⁺ (p = 0.023) central memory T-cells (T_CM; CCR7⁺CD45RA⁻), as well as lower proportions of CD8⁺CD38⁺ T-cells in apheresis samples. In apheresis, a cut-off value of >4.3% of CD8⁺ T_CM predicted strong CAR-T expansion (AUC: 0.80; p = 0.023) and superior progression-free survival (p = 0.04) compared with patients who had CD8⁺ T_CM below the cut-off. Our data suggest that high frequencies of CD8⁺ T_CM cells in apheresis samples may represent a promising pre-treatment biomarker associated with strong CAR-T expansion and superior clinical outcome in r/r LBCL patients following axi-cel. Full article

Background: The interaction between helminth and viral infections has important implications for understanding viral disease outcomes and vaccine efficacy in helminth-endemic regions. We previously demonstrated that helminth seropositivity is associated with reduced Th1/Th17 cytokine levels and reduced COVID-19 severity; however, the underlying immunological mechanisms remain unclear. This study further investigated these mechanisms by assessing how helminth antigens influence SARS-CoV-2-induced T-cell responses in individuals infected with filarial parasites in vitro. Methods: Peripheral blood mononuclear cells (PBMCs) from 43 participants, including Onchocerca volvulus-infected individuals, filarial lymphedema patients, and non-endemic controls, were stimulated in vitro with SARS-CoV-2 peptides and Ascaris lumbricoides antigens. Results: Fluorescence-activated cell sorting analysis showed a significant reduction in SARS-CoV-2-induced CD154 expression on CD4⁺ T cells but an increase on CD8⁺ T cells in O. volvulus-infected participants (p < 0.0001). A. lumbricoides antigens alone did not induce significant T-cell activation in O. volvulus-infected individuals. However, SARS-CoV-2 peptides strongly activated CD4⁺CD154⁺ T cells response (p = 0.0074), but co-stimulation with A. lumbricoides antigens markedly reduced CD3⁺ and CD4⁺CD154⁺ T-cell expression frequencies (p = 0.0329 and p = 0.0452). A. lumbricoides-specific IgG correlated inversely with SARS-CoV-2-induced CD4⁺CD154⁺ expression (r = −0.6025, p = 0.0049), whereas SARS-CoV-2-specific IgG was positively associated with CD4⁺CD154⁺ and CD8⁺CD154⁺ T-cell responses (β = 0.532, p = 0.016 and β = 0.509, p = 0.022). Conclusion: These findings demonstrate that helminth antigens modulate functional SARS-CoV-2-induced T-cell responses, offering a potential mechanism through which helminth co-infections shape antiviral immunity, vaccine efficacy, and clinical disease outcomes. Full article

Maternal immune tolerance and controlled inflammatory responses are essential for fetal development and successful pregnancy. Regulatory T cells (Tregs) and B cells with regulatory properties (Bregs) maintain this balance by limiting excessive immune activation through the secretion of anti-inflammatory and tolerogenic cytokines, such as IL-10, TGF-β, and IL-35. Moreover, alterations in the costimulatory potential of antigen-presenting cells (APCs), including B cells, modulate the activation and differentiation of T cells. Toll-like receptors (TLRs), particularly TLR9, influence B-cell antigen presentation and cytokine production, thereby affecting the balance between pro-inflammatory and tolerogenic responses at the maternal–fetal interface. TLR9 overexpression has been observed in several pregnancy-related disorders in both humans and murine models. In this study, we examine whether blocking TLR9 shortly after mating could improve pregnancy outcomes and modulate the regulatory and antigen-presenting functions of B cells, as well as their interactions with T cells. Using an abortion-prone murine model (CBA/J × DBA/2J), we show that intraperitoneal administration of a TLR9 antagonist (ODN 2088) shortly after mating increases embryo resorption in CBA/J females compared to controls without affecting implantation. Flow cytometry analysis further reveals that mice receiving the TLR9 antagonist are characterized by downregulation of CD80 and upregulation of CD86 on B cells, accompanied by reduced expression of CD40L and CD28 on T cells, as well as a lower percentage of Tregs and activated T cells. In conclusion, blocking TLR9 signaling shortly after mating does not improve pregnancy outcomes; conversely, it exacerbates pregnancy loss in the CBA/J × DBA/2J abortion-prone model, while altering the costimulatory phenotype of B and T cells and impairing Treg development during pregnancy. Full article

Chagas disease, caused by Trypanosoma cruzi, affects a significant proportion of patients who develop digestive and cardiac complications, including megaviscera. This pathogenesis has been associated with autoimmune mechanisms mediated by molecular mimicry. In this study, an in silico evaluation of the potential structural basis of cross-reactivity of β-tubulin 1.9 of T. cruzi and the human β-4A tubulin isoform 3 was conducted. Using bioinformatics tools, homologous regions were identified and potentially immunogenic epitopes were predicted, considering their structural modeling and molecular docking. The proteins shared 87% sequence identity and 95% similarity, with an almost identical structural overlap, RMSD 0.291 Å. Three epitopes, VPFPRLHFF, NDLVSEYQQYQDATI, and GQSGAGNNWAKGHYTEGAELIDS, exhibited high predicted antigenicity, with the 9-mer and 16-mer peptides displaying structurally compatible docking poses within the binding grooves of MHC class I and class II molecules, respectively, while B-cell epitope potential was inferred from sequence-based property predictions. Normal mode analysis, used as an exploratory approach, suggested comparable flexibility profiles for the parasitic- and human-derived peptide–MHC complexes. These findings provide an exploratory structural framework supporting a potential role of β-tubulin epitopes in molecular mimicry processes implicated in the development of chagasic megaviscera. Full article

Paraneoplastic neurological syndromes (PNSs) are immune-mediated disorders caused by an antitumor response that cross-reacts with the nervous system, leading to severe and often irreversible neurological disability. Once considered exceedingly rare, PNSs are now increasingly recognized owing to the identification of novel neural autoantibodies, wider use of commercial testing, and the emergence of immune checkpoint inhibitor (ICI)-related neurotoxicity that phenotypically overlaps with classic PNS. In this narrative review, we performed a structured search of PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar, without date restrictions, to summarize contemporary advances in the epidemiology, pathogenesis, diagnosis, and management of PNS. Population-based data show rising incidence, largely reflecting improved ascertainment and expanding indications for ICIs. Pathogenetically, we distinguish T-cell-mediated syndromes associated with intracellular antigens from antibody-mediated disorders targeting neuronal surface proteins, integrating emerging concepts of molecular mimicry, tumor genetics, and HLA-linked susceptibility. The 2021 PNS-Care criteria are also reviewed, which replace earlier “classical/non-classical” definitions with risk-stratified phenotypes and antibodies, and demonstrate superior diagnostic performance while underscoring that “probable” and “definite” PNS should be managed with equal urgency. Newly described antibodies and methodological innovations such as PhIP-Seq, neurofilament light chain, and liquid biopsy are highlighted, which refine tumor search strategies and longitudinal monitoring. Management principles emphasize early tumor control, prompt immunotherapy, and a growing repertoire of targeted agents, alongside specific considerations for ICI-associated neurological syndromes. Remaining challenges include diagnostic delays, limited high-level evidence, and the paucity of validated biomarkers of disease activity. Future work should prioritize prospective, biomarker-driven trials and multidisciplinary pathways to shorten time to diagnosis and improve long-term outcomes in patients with PNS. Full article

Chimeric antigen receptor (CAR)-T-cell therapy is a revolutionary approach in immunotherapy that has shown remarkable success in the treatment of blood cancers. Many preclinical studies are currently underway worldwide to extend the CAR-T-cell therapy benefits to a broad spectrum of cancers, using rodent models. Alternative in vivo platforms are essential for overcoming the drawbacks associated with rodent models, including immunodeficiency in humanized models, ethical concerns, extended time requirements, and cost. In this work, we used the chicken chorioallantoic membrane (CAM) assay to evaluate the in vivo efficacy of cluster-of-differentiation 19 (CD19)-targeting CAR-T cells expressing a second-generation CAR construct against human lymphoma derived from the Raji cell line. Our results confirm the efficacy of selected CAR-T cells on tumor growth, metastasis, and angiogenesis. Further, the chicken embryo has an intrinsic active immune system. Therefore, the dialog between CAR-T cells and endogenous immune cells, as well as their participation in the tumor challenge, has also been studied. In conclusion, our study demonstrates that the chicken CAM assay provides a relevant in vivo, 3Rs (Replacement, Reduction and Refinement)-compliant new approach methodology (NAM), which is well-suited for the current needs of preclinical research on CAR-T-cell therapy. Full article