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The fate of developing T cells is determined by the strength of T cell receptor (TCR) signal they receive in the thymus. This process is finely regulated through the tuning of positive and negative regulators in thymocytes. The Family with sequence similarity 49 member B (Fam49b) protein is a newly discovered negative regulator of TCR signaling that has been shown to suppress Rac-1 activity in vitro in cultured T cell lines. However, the contribution of Fam49b to the thymic development of T cells is unknown. To investigate this important issue, we generated a novel mouse line deficient in Fam49b (Fam49b-KO). We observed that Fam49b-KO double positive (DP) thymocytes underwent excessive negative selection, whereas the positive selection stage was unaffected. Fam49b deficiency impaired the survival of single positive thymocytes and peripheral T cells. This altered development process resulted in significant reductions in CD4 and CD8 single-positive thymocytes as well as peripheral T cells. Interestingly, a large proportion of the TCRγδ+ and CD8αα+TCRαβ+ gut intraepithelial T lymphocytes were absent in Fam49b-KO mice. Our results demonstrate that Fam49b dampens thymocytes TCR signaling in order to escape negative selection during development, uncovering the function of Fam49b as a critical regulator of the selection process to ensure normal thymocyte development and peripheral T cells survival.

The B cell receptor (BCR) signals together with a multi-component co-receptor complex to initiate B cell activation in response to antigen binding. Here, we take advantage of peroxidase-catalyzed proximity labeling combined with quantitative mass spectrometry to track co-receptor signaling dynamics in Raji cells from 10 s to 2 h after BCR stimulation. This approach enables tracking of 2,814 proximity-labeled proteins and 1,394 phosphosites and provides an unbiased and quantitative molecular map of proteins recruited to the vicinity of CD19, the signaling subunit of the co-receptor complex. We detail the recruitment kinetics of signaling effectors to CD19 and identify previously uncharacterized mediators of B cell activation. We show that the glutamate transporter SLC1A1 is responsible for mediating rapid metabolic reprogramming and for maintaining redox homeostasis during B cell activation. This study provides a comprehensive map of BCR signaling and a rich resource for uncovering the complex signaling networks that regulate activation.

Cellular signaling, crucial for biological processes like immune response and homeostasis, relies on specificity and fidelity in signal transduction to accurately respond to stimuli amidst biological noise. Kinetic proofreading (KPR) is a key mechanism enhancing signaling specificity through time-delayed steps, although its effectiveness is debated due to intrinsic noise potentially reducing signal fidelity. In this study, we reformulate the theory of kinetic proofreading (KPR) by convolving multiple intermediate states into a single state and then define an overall processing time required to traverse these states. This simplification allows us to succinctly describe kinetic proofreading in terms of a single waiting time parameter, facilitating a more direct evaluation and comparison of KPR performance across different biological contexts such as DNA replication and T cell receptor (TCR) signaling. We find that loss of fidelity for longer proofreading steps relies on the specific strategy of information extraction and show that in the first-passage time (FPT) discrimination strategy, longer proofreading steps can exponentially improve the accuracy of KPR at the cost of speed. Thus, KPR can still be an effective discrimination mechanism in the high noise regime. However, in a product concentration-based discrimination strategy, longer proofreading steps do not necessarily lead to an increase in performance. However, by introducing activation thresholds on product concentrations, can we decompose the product-based strategy into a series of FPT-based strategies to better resolve the subtleties of KPR-mediated product discrimination. Our findings underscore the importance of understanding KPR in the context of how information is extracted and processed in the cell.

Insulin is a central autoantigen in the pathogenesis of T1D, and thymic epithelial cell expression of insulin under the control of the Autoimmune Regulator (Aire) is thought to be a key component of maintaining tolerance to insulin. In spite of this general working model, direct detection of this thymic selection on insulin-specific T cells has been somewhat elusive. Here, we used a combination of highly sensitive T cell receptor transgenic models for detecting thymic selection and sorting and sequencing of Insulin-specific CD4+ T cells from Aire-deficient mice as a strategy to further define their selection. This analysis revealed a number of unique t cell receptor (TCR) clones in Aire-deficient hosts with high affinity for insulin/major histocompatibility complex (MHC) ligands. We then modeled the thymic selection of one of these clones in Aire-deficient versus wild-type hosts and found that this model clone could escape thymic negative selection in the absence of thymic Aire. Together, these results suggest that thymic expression of insulin plays a key role in trimming and removing high-affinity insulin-specific T cells from the repertoire to help promote tolerance.

CD4+ T cells recognize peptide antigens presented on class II major histocompatibility complex (MHC-II) molecules to carry out their function. The remarkable diversity of T cell receptor sequences and lack of antigen discovery approaches for MHC-II make profiling the specificities of CD4+ T cells challenging. We have expanded our platform of signaling and antigen-presenting bifunctional receptors to encode MHC-II molecules presenting covalently linked peptides (SABR-IIs) for CD4+ T cell antigen discovery. SABR-IIs can present epitopes to CD4+ T cells and induce signaling upon their recognition, allowing a readable output. Furthermore, the SABR-II design is modular in signaling and deployment to T cells and B cells. Here, we demonstrate that SABR-IIs libraries presenting endogenous and non-contiguous epitopes can be used for antigen discovery in the context of type 1 diabetes. SABR-II libraries provide a rapid, flexible, scalable and versatile approach for de novo identification of CD4+ T cell ligands from single-cell RNA sequencing data using experimental and computational approaches.

While studying transgene expression after systemic administration of lentiviral vectors, we found that splenic B cells are robustly transduced, regardless of the types of pseudotyped envelope proteins. However, the administration of two different pseudotypes resulted in transduction of two distinct B cell populations, suggesting that each pseudotype uses unique and specific receptors for its attachment and entry into splenic B cells. Single-cell RNA sequencing analysis of the transduced cells demonstrated that different pseudotypes transduce distinct B cell subpopulations characterized by specific B cell receptor (BCR) genotypes. Functional analysis of the BCRs of the transduced cells demonstrated that BCRs specific to the pseudotyping envelope proteins mediate viral entry, enabling the vectors to selectively transduce the B cell populations that are capable of producing antibodies specific to their envelope proteins. Lentiviral vector entry via the BCR activated the transduced B cells and induced proliferation and differentiation into mature effectors, such as memory B and plasma cells. BCR-mediated viral entry into clonally specific B cell subpopulations raises new concepts for understanding the biodistribution of transgene expression after systemic administration of lentiviral vectors and offers new opportunities for BCR-targeted gene delivery by pseudotyped lentiviral vectors.

The differentiation of naive CD8+ T cells into effector cells is important for establishing immunity. However, the effect of heterogeneous naive CD8+ T cell populations is not fully understood. Here, we demonstrate that steady-state naive CD8+ T cells are composed of functionally heterogeneous subpopulations that differ in their ability to differentiate into type 17 cytotoxic effector cells (Tc17) in a context of murine inflammatory disease models, such as inflammatory bowel disease and graft-versus-host disease. The differential ability of Tc17 differentiation is not related to T-cell receptor (TCR) diversity and antigen specificity but is inversely correlated with self-reactivity acquired during development. Mechanistically, this phenomenon is linked to differential levels of intrinsic TCR sensitivity and basal Suppressor of Mothers Against Decapentaplegic 3 (SMAD3) expression, generating a wide spectrum of Tc17 differentiation potential within naive CD8+ T cell populations. These findings suggest that developmental self-reactivity can determine the fate of naive CD8+ T cells to generate functionally distinct effector populations and achieve immense diversity and complexity in antigen-specific T-cell immune responses.

The ability to selectively bind to antigenic peptides and secrete effector molecules can define rare and low-affinity populations of cells with therapeutic potential in emerging T cell receptor (TCR) immunotherapies. We leverage cavity-containing hydrogel microparticles, called nanovials, each coated with peptide-major histocompatibility complex (pMHC) monomers to isolate antigen-reactive T cells. T cells are captured and activated by pMHCs inducing the secretion of effector molecules including IFN-γ and granzyme B that are accumulated on nanovials, allowing sorting based on both binding and function. The TCRs of sorted cells on nanovials are sequenced, recovering paired αβ-chains using microfluidic emulsion-based single-cell sequencing. By labeling nanovials having different pMHCs with unique oligonucleotide-barcodes and secretions with oligo-barcoded detection antibodies, we could accurately link TCR sequences to specific targets and rank each TCR based on the corresponding cells secretion level. Using the technique, we identified an expanded repertoire of functional TCRs targeting viral antigens with high specificity and found rare TCRs with activity against cancer-specific splicing-enhanced epitopes.

Pluripotent stem cells (PSCs) are a promising source of allogeneic T cells for off-the-shelf immunotherapies. However, the process of differentiating genetically engineered PSCs to generate mature T cells requires that the same molecular elements that are crucial for the selection of these cells be removed to prevent alloreactivity. Here we show that antigen-restricted mature T cells can be generated in vitro from PSCs edited via CRISPR to lack endogenous T cell receptors (TCRs) and class I major histocompatibility complexes. Specifically, we used T cell precursors from RAG1-/-RAG2-/-B2M-/- human PSCs expressing a single TCR, and a murine stromal cell line providing the cognate human major histocompatibility complex molecule and other critical signals for T cell maturation. Possibly owing to the absence of TCR mispairing, the generated T cells showed substantially better tumour control in mice than T cells with an intact endogenous TCR. Introducing the T cell selection components into the stromal microenvironment of the PSCs overcomes inherent biological challenges associated with the development of T cell immunotherapies from allogeneic PSCs.

Programmed death-ligand 1 (PD-L1) is a promising target for cancer immunotherapy due to its ability to inhibit T cell activation; however, its expression on various noncancer cells may cause on-target off-tumor toxicity when designing PD-L1-targeting Chimeric Antigen Receptor (CAR) T cell therapies. Combining rational design and directed evolution of the human fibronectin-derived monobody scaffold, PDbody was engineered to bind to PD-L1 with a preference for a slightly lower pH, which is typical in the tumor microenvironment. PDbody was further utilized as a CAR to target the PD-L1-expressing triple negative MDA-MB-231 breast cancer cell line. To mitigate on-target off-tumor toxicity associated with targeting PD-L1, a Cluster of Differentiation 19 (CD19)-recognizing SynNotch IF THEN gate was integrated into the system. This CD19-SynNotch PDbody-CAR system was then expressed in primary human T cells to target CD19-expressing MDA-MB-231 cancer cells. These CD19-SynNotch PDbody-CAR T cells demonstrated both specificity and efficacy in vitro, accurately eradicating cancer targets in cytotoxicity assays. Moreover, in an in vivo bilateral murine tumor model, they exhibited the capability to effectively restrain tumor growth. Overall, CD19-SynNotch PDbody-CAR T cells represent a distinct development over previously published designs due to their increased efficacy, proliferative capability, and mitigation of off-tumor toxicity for solid tumor treatment.

Treatment of hematologic malignancies with patient-derived anti-CD19 chimeric antigen receptor (CAR) T-cells has demonstrated long-term remissions for patients with otherwise treatment-refractory advanced leukemia and lymphoma. Conversely, CAR T-cell treatment of solid tumors, including advanced gastric cancer (GC), has proven more challenging due to on-target off-tumor toxicities, poor tumor T-cell infiltration, inefficient CAR T-cell expansion, immunosuppressive tumor microenvironments, and demanding preconditioning regimens. We report the exceptional results of autologous Claudin18.2-targeted CAR T cells (CT041) in a patient with metastatic GC, who had progressed on four lines of combined systemic chemotherapy and immunotherapy. After two CT041 infusions, the patient had target lesion complete response and sustained an 8-month overall partial response with only minimal ascites. Moreover, tumor-informed circulating tumor DNA (ctDNA) reductions coincided with rapid CAR T-cell expansion and radiologic response. No severe toxicities occurred, and the patient's quality of life significantly improved. This experience supports targeting Claudin18.2-positive GC with CAR T-cell therapy and helps to validate ctDNA as a biomarker in CAR T-cell therapy. Clinical Insight: Claudin18.2-targeted CAR T cells can safely provide complete objective and ctDNA response in salvage metastatic GC.

Roughly one-half of mice with partial defects in two immune tolerance pathways (AireGW/+Lyn-/- mice) spontaneously develop severe damage to their retinas due to T cell reactivity to Aire-regulated interphotoreceptor retinoid-binding protein (IRBP). Single-cell T cell receptor (TCR) sequencing of CD4+ T cells specific for a predominate epitope of IRBP showed a remarkable diversity of autoantigen-specific TCRs with greater clonal expansions in mice with disease. TCR transgenic mice made with an expanded IRBP-specific TCR (P2.U2) of intermediate affinity exhibited strong but incomplete negative selection of thymocytes. This negative selection was absent in IRBP-/- mice and greatly defective in AireGW/+ mice. Most P2.U2+/- mice and all P2.U.2+/-AireGW/+ mice rapidly developed inflammation of the retina and adjacent uvea (uveitis). Aire-dependent IRBP expression in the thymus also promoted Treg differentiation, but the niche for this fate determination was small, suggesting differences in antigen presentation leading to negative selection vs. thymic Treg differentiation and a stronger role for negative selection in preventing autoimmune disease in the retina.

BACKGROUND: The clustering of immune repertoire data is challenging due to the computational cost associated with a very large number of pairwise sequence comparisons. To overcome this limitation, we developed Anchor Clustering, an unsupervised clustering method designed to identify similar sequences from millions of antigen receptor gene sequences. First, a Point Packing algorithm is used to identify a set of maximally spaced anchor sequences. Then, the genetic distance of the remaining sequences to all anchor sequences is calculated and transformed into distance vectors. Finally, distance vectors are clustered using unsupervised clustering. This process is repeated iteratively until the resulting clusters are small enough so that pairwise distance comparisons can be performed. RESULTS: Our results demonstrate that Anchor Clustering is faster than existing pairwise comparison clustering methods while providing similar clustering quality. With its flexible, memory-saving strategy, Anchor Clustering is capable of clustering millions of antigen receptor gene sequences in just a few minutes. CONCLUSIONS: This method enables the meta-analysis of immune-repertoire data from different studies and could contribute to a more comprehensive understanding of the immune repertoire data space.

ObjectivesThe Kirsten rat sarcoma virus (KRAS) G12D oncogenic mutation poses a significant challenge in treating solid tumors due to the lack of specific and effective therapeutic interventions. This study aims to explore innovative approaches in T cell receptor (TCR) engineering and characterization to target the KRAS G12D7-16 mutation, providing potential strategies for overcoming this therapeutic challenge.MethodsIn this innovative study, we engineered and characterized two T cell receptors (TCRs), KDA11-01 and KDA11-02 with high affinity for the KRAS G12D7-16 mutation. These TCRs were isolated from tumor-infiltrating lymphocytes (TILs) derived from tumor tissues of patients with the KRAS G12D mutation. We assessed their specificity and anti-tumor activity in vitro using various cancer cell lines.ResultsKDA11-01 and KDA11-02 demonstrated exceptional specificity for the HLA-A*11:01-restricted KRAS G12D7-16 epitope, significantly inducing IFN-γ release and eliminating tumor cells without cross-reactivity or alloreactivity.ConclusionsThe successful development of KDA11-01 and KDA11-02 introduces a novel and precise TCR-based therapeutic strategy against KRAS G12D mutation, showing potential for significant advancements in cancer immunotherapy.

IntroductionThe domestic cat (Felis catus) is a valued companion animal and a model for virally induced cancers and immunodeficiencies. However, species-specific limitations such as a scarcity of immune cell markers constrain our ability to resolve immune cell subsets at sufficient detail. The goal of this study was to characterize circulating feline T cells and other leukocytes based on their transcriptomic landscape and T-cell receptor repertoire using single cell RNA-sequencing.MethodsPeripheral blood from 4 healthy cats was enriched for T cells by flow cytometry cell sorting using a mouse anti-feline CD5 monoclonal antibody. Libraries for whole transcriptome, αβ T cell receptor transcripts and γδ T cell receptor transcripts were constructed using the 10x Genomics Chromium Next GEM Single Cell 5' reagent kit and the Chromium Single Cell V(D)J Enrichment Kit with custom reverse primers for the feline orthologs.ResultsUnsupervised clustering of whole transcriptome data revealed 7 major cell populations - T cells, neutrophils, monocytic cells, B cells, plasmacytoid dendritic cells, mast cells and platelets. Sub cluster analysis of T cells resolved naive (CD4+ and CD8+), CD4+ effector T cells, CD8+ cytotoxic T cells and γδ T cells. Cross species analysis revealed a high conservation of T cell subsets along an effector gradient with equitable representation of veterinary species (horse, dog, pig) and humans with the cat. Our V(D)J repertoire analysis identified a subset of CD8+ cytotoxic T cells with skewed TRA and TRB gene usage, conserved TRA and TRB junctional motifs, restricted TRA/TRB pairing and reduced diversity in TRG junctional length. We also identified a public γδ T cell subset with invariant TRD and TRG chains and a CD4+ TEM-like phenotype. Among monocytic cells, we resolved three clusters of classical monocytes with polarization into pro- and anti-inflammatory phenotypes in addition to a cluster of conventional dendritic cells. Lastly, our neutrophil sub clustering revealed a larger mature neutrophil cluster and a smaller exhausted/activated cluster.DiscussionOur study is the first to characterize subsets of circulating T cells utilizing an integrative approach of single cell RNA-sequencing, V(D)J repertoire analysis and cross species analysis. In addition, we characterize the transcriptome of several myeloid cell subsets and demonstrate immune cell relatedness across different species.

Despite advancements in cancer immunotherapy, solid tumors remain formidable challenges. In glioma, profound inter- and intra-tumoral heterogeneity of antigen landscape hampers therapeutic development. Therefore, it is critical to consider alternative sources to expand the repertoire of targetable (neo-)antigens and improve therapeutic outcomes. Accumulating evidence suggests that tumor-specific alternative splicing (AS) could be an untapped reservoir of antigens. In this study, we investigated tumor-specific AS events in glioma, focusing on those predicted to generate major histocompatibility complex (MHC)-presentation-independent, cell-surface antigens that could be targeted by antibodies and chimeric antigen receptor-T cells. We systematically analyzed bulk RNA-sequencing datasets comparing 429 tumor samples (from The Cancer Genome Atlas) and 9166 normal tissue samples (from the Genotype-Tissue Expression project), and identified 13 AS events in 7 genes predicted to be expressed in more than 10% of the patients, including PTPRZ1 and BCAN, which were corroborated by an external RNA-sequencing dataset. Subsequently, we validated our predictions and elucidated the complexity of the isoforms using full-length transcript amplicon sequencing on patient-derived glioblastoma cells. However, analyses of the RNA-sequencing datasets of spatially mapped and longitudinally collected clinical tumor samples unveiled remarkable spatiotemporal heterogeneity of the candidate AS events. Furthermore, proteomics analysis did not reveal any peptide spectra matching the putative antigens. Our investigation illustrated the diverse characteristics of the tumor-specific AS events and the challenges of antigen exploration due to their notable spatiotemporal heterogeneity and elusive nature at the protein levels. Redirecting future efforts toward intracellular, MHC-presented antigens could offer a more viable avenue.

Exposure to allogenic red blood cells (RBCs), either through pregnancy or transfusion, can result in alloimmunization, which can lead to severe hemolytic transfusion reactions and pregnancy complications. Passively administered antibodies can be used to prevent alloimmunization, where steric hindrance of allogeneic epitopes has been postulated as one mechanism whereby antibody engagement may prevent RBC alloimmunization. However, the dynamics of antibody engagement on the RBC surface has remained difficult to study. To examine this, we leveraged the HOD (HEL, OVA and Duffy) model system and Fcγ receptor knockout recipients to define the dynamics of antibody engagement of the Duffy antigen in the absence of RBC clearance or antigen modulation. Using this approach, the on-rate of antibody engagement of HOD RBCs was very similar in vivo and in vitro , with high levels of antibody binding observed within minutes of HOD RBC exposure. In contrast, the off-rate of HOD RBC bound antibody was relatively slow, with appreciable dissociation not being observed for an hour. However, the dynamics of antibody interactions with HOD changed significantly when antibody decorated HOD RBCs were exposed to free antibody. Despite the presence of prebound antibody, free antibody rapidly associated with HOD RBCs, with the rate of free antibody association observed being faster in vivo than in vitro. Importantly, antibody association and dissociation occurred in the absence of any appreciable changes in RBC clearance, antigen modulation or complement deposition, suggesting that differences in antibody levels observed reflected actual differences in the dynamics of antibody binding. These results suggest that while antibodies appear to be relatively static on the cell surface once bound, antibody engagement can be quite dynamic, especially in the face of free antibody in solution. These results not only have implications in the mechanisms of antibody-mediated immunosuppression, but also the potential use of other antibody-based approaches designed to prevent hemolytic transfusion reactions or target antigens in vivo in general. [ABSTRACT FROM AUTHOR]

Glycopeptides derived from the glycoprotein mucin‐1 (MUC1) have shown potential as tumor‐associated antigens for cancer vaccine development. However, their low immunogenicity and non‐selective conjugation to carriers present significant challenges for the clinical efficacy of MUC1‐based vaccines. Here, we introduce a novel vaccine candidate based on a structure‐guided design of an artificial antigen derived from MUC1 glycopeptide. This engineered antigen contains two non‐natural amino acids and has an α‐S‐glycosidic bond, where sulfur replaces the conventional oxygen atom linking the peptide backbone to the sugar N‐acetylgalactosamine. The glycopeptide is then specifically conjugated to the immunogenic protein carrier CRM197 (Cross‐Reactive Material 197), a protein approved for human use. Conjugation involves selective reduction and re‐bridging of a disulfide in CRM197, allowing the attachment of a single copy of MUC1. This strategy results in a chemically defined vaccine while maintaining both the structural integrity and immunogenicity of the protein carrier. The vaccine elicits a robust Th1‐like immune response in mice and generates antibodies capable of recognizing human cancer cells expressing tumor‐associated MUC1. When tested in mouse models of colon adenocarcinoma and pancreatic cancer, the vaccine is effective both as a prophylactic and therapeutic use, significantly delaying tumor growth. In therapeutic applications, improved outcomes were observed when the vaccine was combined with an anti‐programmed cell death protein 1 (anti‐PD‐1) checkpoint inhibitor. Our strategy reduces batch‐to‐batch variability and enhances both immunogenicity and therapeutic potential. This site‐specific approach disputes a prevailing dogma where glycoconjugate vaccines require multivalent display of antigens. [ABSTRACT FROM AUTHOR]

Antibody therapeutics in oncology can have high cytotoxic potential, which demands superior on-tumor selectivity. Antibody selectivity can be boosted through molecular engineering strategies that exploit the unique characteristics of the tumor and the tumor microenvironment. Strategies, such as superselectivity, dual targeting, conditional binding, inverse targeting, and combinations of molecules, can help boost the selectivity of biologics for tumor cells. Intracellular tumor antigens are becoming increasingly accessible to biologics through approaches including T cell receptor mimicry, intracellular delivery, and transcytosis. Antibodies in oncology are being equipped with toxic cargoes and effector functions that can kill cells at very low concentrations. A key challenge is that most targets on cancer cells are also present on at least some healthy cells. Shared targets can result in off-tumor binding and compromise the safety and potential of therapeutic candidates. In this review, we survey strategies that can help direct biologics to cancer sites more selectively. These strategies are becoming increasingly feasible thanks to advances in molecular design and engineering. The objective is to create therapeutics that exploit changes in cancer and leverage the human body infrastructure, enabling therapeutics that discriminate not just self from non-self but diseased from healthy tissue. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) ranks among the most prevalent cancers worldwide, highlighting the urgent need for improved diagnostic and therapeutic methodologies. The standard treatment regimen generally involves surgical intervention followed by systemic therapies; however, the median survival rates for patients remain unsatisfactory. Chimeric antigen receptor (CAR) T-cell therapy has emerged as a pivotal advancement in cancer treatment. Both clinical and preclinical studies emphasize the notable efficacy of CAR T cells in targeting HCC. Various molecules, such as GPC3, c-Met, and NKG2D, show significant promise as potential immunotherapeutic targets in liver cancer. Despite this, employing CAR T cells to treat solid tumors like HCC poses considerable challenges within the discipline. Numerous innovations have significant potential to enhance the efficacy of CAR T-cell therapy for HCC, including improvements in T cell trafficking, strategies to counteract the immunosuppressive tumor microenvironment, and enhanced safety protocols. Ongoing efforts to discover therapeutic targets for CAR T cells highlight the need for the development of more practical manufacturing strategies for CAR-modified cells. This review synthesizes recent findings and clinical advancements in the use of CAR T-cell therapies for HCC treatment. We elucidate the therapeutic benefits of CAR T cells in HCC and identify the primary barriers to their broader application. Our analysis aims to provide a comprehensive overview of the current status and future prospects of CAR T-cell immunotherapy for HCC. [ABSTRACT FROM AUTHOR]

The lack of symptoms in the early stages of liver disease may cause wrong diagnosis of the disease by many doctors and endanger the health of patients. Therefore, earlier and more accurate diagnosis of liver problems is necessary for proper treatment and prevention of serious damage to this vital organ. We attempted to develop an intelligent system to detect liver failure using data mining and artificial neural networks (ANN), this approach considers all factors impacting patient identification and enhances the probability of success in diagnosing liver failure. We employ multilayer perceptron neural networks for diagnosing liver failure via a liver patient dataset (ILDP). The proposed approach using the backpropagation algorithm, improves the diagnosis rate, and predicts liver failure intelligently. The simulation and data analysis outputs revealed that the proposed method has 99.5% accuracy, 99.65% sensitivity, and 99.57% specificity, making it more accurate than Previous related methods. [ABSTRACT FROM AUTHOR]

Follow-up of previously healthy patients surviving cryptococcal meningitis found that cryptococcal antigen could be detected for >1 year in serum from 38 of 44 (86%) patients and in cerebrospinal fluid (CSF) from 20 of 31 patients (67%), far beyond the time of culture conversion. The speed of titer decline, measured as the number of days for a 2-fold drop in titer to occur, was slower in serum than in CSF. The speed of decline of antigen titers was much slower in serum and CSF for patients infected with Cryptococcus gattii than Cryptococcus neoformans. The speed of decline in CSF and serum titers was also much slower in patients who had received a ventriculoperitoneal shunt for increased intracranial pressure. The variable and extraordinarily slow rate of clearance in our patients did not appear to reflect differences in disease control but rather differences in species and shunting for increased intracranial pressure. [ABSTRACT FROM AUTHOR]

It is a fact that sperm possess antigenic properties. Substantial scientific research suggests that specific antibodies that attach to sperm antigens can induce infertility in both humans and other species. Antisperm antibodies (ASA) represent a significant etiology of infertility in humans, leading to immunoinfertility. The association between ASA and infertility is multifaceted. The observation of sperm agglutination, although not conclusive for the diagnosis of immunological infertility, may suggest the presence of ASA. Nevertheless, ASA may also manifest in the lack of any sperm agglutination. Managing ASA from an andrological perspective depends on the underlying cause and the specific approaches healthcare professionals adopt. The precise etiology of male infertility resulting from ASA remains unclear. Current research has examined the impact of ASA and its prevalence among infertile males to understand the relationship between ASA and changes in semen parameters. However, the findings have been inconclusive. Numerous techniques have been documented for the management of immunoinfertility. This review examines the importance of ASA in the context of infertility, encompassing the postulated mechanisms underlying the development of ASA, the various assays employed for detecting them, and the available treatments. [ABSTRACT FROM AUTHOR]

[Display omitted] • CDs and CMs with good biocompatibility were prepared. • CMB and CMC stimulated the maturation of DC cells and activated T cells. • CMB and CMC can target LNs and induce an immune response to treat primary and distal tumor models. • CMB and CMC can specifically target B16F10 and CT26 tumors, respectively. Although therapeutic nanovaccines have made a mark in cancer immunotherapy, the shortcomings such as poor homing ability of lymph nodes (LNs), low antigen presentation efficiency and low antitumor efficacy have hindered their clinical transformation. Accordingly, we prepared advanced nanovaccines (CMB and CMC) by integrating carbon dots (CDs) with tumor-associated antigens (B16F10 and CT26). These nanovaccines could forwardly target tumors harbouring LNs, induce strong immunogenicity for activating cytotoxic T cells (CTLs), thereby readily eliminating tumor cells and suppressing primary/distal tumor growth. This work provides a promising therapeutic vaccination strategy to enhance cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Introduction: ER aminopeptidase 1 (ERAP1) is a polymorphic intracellular aminopeptidase with key roles in antigen presentation and adaptive immune responses. ERAP1 allotype 10 is highly protective toward developing some forms of autoimmunity and displays unusual functional properties, including very low activity versus some substrates. Methods: To understand the molecular mechanisms that underlie the biology of allotype 10, we studied its enzymatic and biophysical properties focusing on its unique polymorphisms V349M and Q725R. Results: Compared to ancestral allotype 1, allotype 10 is much less effective in trimming small substrates but presents allosteric kinetics that ameliorate activity differences at high substrate concentrations. Furthermore, it is inhibited by a transition-state analogue via a non-competitive mechanism and is much less responsive to an allosteric small-molecule modulator. It also presents opposite enthalpy, entropy, and heat capacity of activation compared to allotype 1, and its catalytic rate is highly dependent on viscosity. Polymorphisms V349M and Q725R significantly contribute to the lower enzymatic activity of allotype 10 for small substrates, especially at high substrate concentrations, influence the cooperation between the regulatory and active sites, and regulate viscosity dependence, likely by limiting product release. Conclusions: Overall, our results suggest that allotype 10 is not just an inactive variant of ERAP1 but rather carries distinct enzymatic properties that largely stem from changes at positions 349 and 725. These changes affect kinetic and thermodynamic parameters that likely control rate-limiting steps in the catalytic cycle, resulting in an enzyme optimized for sparing small substrates and contributing to the homeostasis of antigenic epitopes in the ER. [ABSTRACT FROM AUTHOR]

Objectives: Despite surgical resection, chemoradiation, and targeted therapy, brain tumors remain a leading cause of cancer-related death in children. Immunotherapy has shown some promise and is actively being investigated for treating childhood brain tumors. However, a critical step in advancing immunotherapy for these patients is to uncover targets that can be effectively translated into therapeutic interventions. Methods: In this study, our team performed a transcriptomic analysis across pediatric brain tumor types to identify potential targets for immunotherapy. Additionally, we assessed components that may impact patient response to immunotherapy, including the expression of genes essential for antigen processing and presentation, inhibitory ligands and receptors, interferon signature, and overall predicted T cell infiltration. Results: We observed distinct expression patterns across tumor types. These included elevated expression of antigen genes and antigen processing machinery in some tumor types while other tumors had elevated inhibitory checkpoint receptors, known to be associated with response to checkpoint inhibitor immunotherapy. Conclusion: These findings suggest that pediatric brain tumors exhibit distinct potential for specific immunotherapies. We believe our findings can guide investigators in their assessment of appropriate immunotherapy classes and targets in pediatric brain tumors. [ABSTRACT FROM AUTHOR]

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Background: Dormancy survival regulator (DosR) and resuscitation-promoting factor (Rpf) antigens of Mycobacterium tuberculosis are activated during dormant phase of tuberculosis (TB). This study evaluates the differential immunogenicity potentials of DosR and Rpf antigens in individuals with latent tuberculosis infection (LTBI) and active TB patients. Methods: After a literature search in electronic databases, studies were selected by following precise eligibility criteria. Outcomes were synthesized systematically, and meta-analyses were performed to estimate standardized mean differences (SMDs) in interferon-gamma (IFNγ) levels, and IFNγ positive immune cells between individuals with LTBI and active TB patients. Results: Twenty-six studies (1278 individuals with LTBI and 1189 active TB patients) were included. DosR antigens Rv0569 (Standardized mean difference; SMD 2.44 [95%CI: 1.21, 3.66]; p < 0.0001), Rv1733c (SMD 0.60 [95%CI: 0.14, 1.07]; p = 0.011), Rv1735c (SMD 1.16 [95%CI: 0.44, 1.88]; p = 0.002), Rv1737c (SMD 1.26 [95%CI: 0.59, 1.92]; p < 0.0001), Rv2029c (SMD 0.89 [95%CI: 0.35, 1.42]; p = 0.002), RV2626c (SMD 1.24 [95%CI: 0.45, 2.02); p = 0.002), and Rv2628 (SMD 0.65 [95%CI: 0.38, 0.91]; p < 0.0001) and Rpf antigens Rv0867c (SMD 1.33 [95%CI: 0.48, 2.18]; p = 0.002), Rv1009 (SMD 0.65 [95%CI: 0.05, 1.25]; p = 0.034), and Rv2450c (SMD 1.54 [95%CI: 0.92, 2.16]; p < 0.0001) elicited higher IFNγ levels in individuals with LTBI in comparison with active TB patients. IFNγ-positive immunoresponsive cells were significantly higher in individuals with LTBI than in active TB patients for antigens Rv1733c (SMD 1.02 [95%CI: 0.15, 1.88]; p = 0.021), Rv2029c (SMD 0.57 [95%CI: 0.05, 1.09]; p = 0.031), and Rv2628 [SMD 0.38 [95%CI: 0.15, 0.61]; p = 0.001). Conclusion: DosR antigens Rv0569, Rv1733c, Rv1735c, Rv1737c, RV2626c, Rv2628, and Rv2029c, and Rpf antigens Rv0867c, Rv1009, and Rv2450c are found to elicit immune responses differently in individuals with LTBI and active TB patients. [ABSTRACT FROM AUTHOR]

Simple Summary: This mini-review summarizes the up-to-date progress in developing anticancer therapies based on cutting-edge strategies employing short peptides. This work serves as a guide to the versatility of short peptide-based applications in cancer diagnosis and treatment. Starting with a brief introduction to the unique features of short peptides and peptide self-assemblies, including their pros and cons, we outline short peptide sequences in terms of their specific functions, such as immunotherapeutic drugs, supramolecular vaccines, antigens, and adjuvants. We highlight self-assembled peptides as scaffolds for targeted delivery or co-delivery of multiple therapeutics and genes. We also emphasize the relevance of short peptides in combinatorial immuno- and traditional therapies, 3D culture, and cancer imaging. Finally, we explore ultra-short natural bioactive peptides as potential anticancer agents. Short peptides have been coming around as a strong weapon in the fight against cancer on all fronts—in immuno-, chemo-, and radiotherapy, and also in combinatorial approaches. Moreover, short peptides have relevance in cancer imaging or 3D culture. Thanks to the natural 'smart' nature of short peptides, their unique structural features, as well as recent progress in biotechnological and bioinformatics development, short peptides are playing an enormous role in evolving cutting-edge strategies. Self-assembling short peptides may create excellent structures to stimulate cytotoxic immune responses, which is essential for cancer immunotherapy. Short peptides can help establish versatile strategies with high biosafety and effectiveness. Supramolecular short peptide-based cancer vaccines entered clinical trials. Peptide assemblies can be platforms for the delivery of antigens, adjuvants, immune cells, and/or drugs. Short peptides have been unappreciated, especially in the vaccine aspect. Meanwhile, they still hide the undiscovered unlimited potential. Here, we provide a timely update on this highly active and fast-evolving field. [ABSTRACT FROM AUTHOR]

Maize lethal necrosis (MLN) is a maize disease caused by the maize chlorotic mottle virus (MCMV), a potyvirus which causes yield losses of 30–100%. The present study aimed to isolate nanobodies against the MCMV coat protein (CP) for the diagnosis of MLN. MCMV CP expressed in Escherichia coli was used for llama immunization. VHH (i.e. variable heavy domain of heavy chain) gene fragments were prepared from blood drawn from the immunized llama and used to generate a library in E. coli TG1 cells. MCMV specific nanobodies were selected by three rounds of phage display and panning against MCMV CP. The selected nanobodies were finally expressed in E. coli WK6 cells and purified. Eleven MCMV‐specific nanobodies were identified and shown to detect MCMV in infected maize plants. Thus, our results show that nanobodies isolated from llama immunized with MCMV CP can distinguish infected and healthy maize plants, potentially enabling development of affordable MCMV detection protocols. [ABSTRACT FROM AUTHOR]

Rationale: Sarcoidosis is a systemic granulomatous disorder associated with hypergammaglobulinemia and the presence of autoantibodies. The specific antigens initiating granulomatous inflammation in sarcoidosis are unknown, and there is no specific test available to diagnose sarcoidosis. To discover novel sarcoidosis antigens, we developed a high-throughput T7 phage display library derived from the sarcoidosis cDNA and identified numerous clones differentiating sarcoidosis from other respiratory diseases. After clone sequencing and a homology search, we identified two epitopes (cofilin μ and chain A) that specifically bind to serum IgGs of patients with sarcoidosis. Objectives: To develop and validate an epitope-specific IgG-based immunoassay specific for sarcoidosis. Methods: We chemically synthesized both immunoepitopes (cofilin μ and chain A) and generated rabbit polyclonal antibodies against both neoantigens. After extensive standardization, we developed a direct peptide ELISA and measured epitope-specific IgG in the sera of 386 subjects, including healthy control subjects (n = 100), three sarcoidosis cohorts (n = 186), pulmonary tuberculosis (n = 70), and lung cancer (n = 30). Measurements and Main Results: To develop a model to classify sarcoidosis distinctly from other groups, data were analyzed using fivefold cross-validation when adjusting for confounders. The cofilin μ IgG model yielded a mean sensitivity, specificity, and positive and negative predictive value of 0.97, 0.9, 0.9, and 0.96, respectively. Those same measures for chain A IgG antibody were 0.9, 0.83, 0.84, and 0.9, respectively. Combining both biomarkers improved the area under the curve, sensitivity, specificity, and positive and negative predictive value. Conclusions: These results provide a novel immunoassay for sarcoidosis. The discovery of two neoantigens facilitates the development of biospecific drug discovery and the sarcoidosis-specific model. [ABSTRACT FROM AUTHOR]

Fasciolosis is an important disease of livestock with increasing reports of human infection, caused by the helminth parasite Fasciola. In this study, we report a preliminary approach towards the development of immunosensors based on nanostructured porous silicon for the detection of Fasciola infection. The surface of porous silicon was biofunctionalized by the deposition of 3-aminopropyltriethoxysilane (APTS) from solution, leading to high density of amine groups covering the surface which would promote the further immobilization of biomolecules like antibodies. The antibody against bacterial collagenase IV binds with porous silicon and its variable region binds with Fasciola gigantica excretory/secretory (ES) products which were then detected by observing the apple green colour under fluorescence microscope by using fluorescein isothiocyanate (FITC) labeled bacterial collagenase IV antibody. In addition the FTIR study was also performed. The present study suggests the possibility of using porous silicon as immunosensors for F. gigantica infection detection with low cost and high sensitivity. [ABSTRACT FROM AUTHOR]

Gordon C Ibeanu,1 Adekunle B Rowaiye,1,2 Joy C Okoli,1 Daniel U Eze1 1Department of Pharmaceutical Sciences, North Carolina Central University, Durham, NC, 27707, USA; 2Department of Agricultural Biotechnology, National Biotechnology Development Agency, Abuja, NigeriaCorrespondence: Adekunle B Rowaiye, Department of Pharmaceutical Sciences, North Carolina Central University, Durham, NC, 27707, USA, Tel +1-9193812004, Email adekunlerowaiye@gmail.comBackground: Colorectal cancer (CRC) is the third most prevalent cancer worldwide, with numerous risk factors contributing to its development. Recent research has illuminated the significant role of the gut microbiota in CRC pathogenesis, identifying various microbial antigens as potential targets for vaccine development.Aim: This review aimed at exploring the potential sources of microbial antigens that could be harnessed to create effective CRC vaccines and understand the role of microbiome-CRC interactions in carcinogenesis.Methods: A comprehensive search of original research and review articles on the pathological links between key microbial candidates, particularly those more prevalent in CRC tissues, was conducted. This involved extensive use of the PubMed and Medline databases, as well as the Google Scholar search engine, utilizing pertinent keywords. A total of one hundred and forty-three relevant articles in English, mostly published between 2018 and 2024, were selected.Results: Numerous microbes, particularly bacteria and viruses, are significantly overrepresented in CRC tissues and have been shown to promote tumorigenesis by inducing inflammation and modulating the immune system. This makes them promising candidates for antigens in the development of CRC vaccines.Conclusion: The selection of microbial antigens focuses on their capacity to trigger a strong immune response and their link to tumor presence and progression. Identifying and validating these antigens through preclinical testing is essential in developing a CRC vaccine.Plain Language Summary: Colorectal cancer (CRC) is a common and serious disease that affects many people worldwide. Research has shown that the bacteria and other microorganisms in our gut play a significant role in the development of CRC. This review aimed to identify specific microbial targets that could be used to develop effective vaccines against CRC.The researchers searched through numerous scientific articles and found that certain bacteria and viruses are more commonly found in CRC tissues and promote tumor growth by causing inflammation and affecting the immune system. These microbes have the potential to be used as antigens in CRC vaccines.The identification of these antigens is a crucial step towards developing a vaccine that can prevent or treat CRC. Further research is needed to validate these findings and move closer to creating an effective vaccine against this disease.In simpler terms, this research is exploring how the gut microbiome contributes to colorectal cancer and searching for specific targets to develop a vaccine that can help prevent or treat the disease.Keywords: colorectal cancer, microbe, antigen, vaccine, tumor

Introduction Hookworms infect about half a billion people worldwide and are responsible for the loss of more than two billion disability-adjusted life years. Mass drug administration (MDA) is the most popular preventive approach, but it does not prevent reinfection. An effective vaccine would be a major public health tool in hookworm-endemic areas.Areas covered We highlight recent human studies where vaccination with irradiated larvae and repeated rounds of infection-treatment have induced partial protection. These studies have emphasized the importance of targeting the infective larvae to generate immunity to prevent adult worms from maturing in the gut. We summarize the current status of human and animal model vaccine trials.Expert opinion Hookworm infection is endemic in resource-poor developing regions where polyparasitism is common, and vaccine cold chain logistics are complex. Humans do not develop sterile immunity to hookworms, and the elderly are frequently overlooked in MDA campaigns. For all these reasons, a vaccine is essential to create long-lasting protection. The lack of a robust animal model to mimic human hookworm infections is a barrier to the discovery and development of a vaccine, however, there have been major recent advances in human challenge studies which will accelerate the process.

Abstract Background Dormancy survival regulator (DosR) and resuscitation-promoting factor (Rpf) antigens of Mycobacterium tuberculosis are activated during dormant phase of tuberculosis (TB). This study evaluates the differential immunogenicity potentials of DosR and Rpf antigens in individuals with latent tuberculosis infection (LTBI) and active TB patients. Methods After a literature search in electronic databases, studies were selected by following precise eligibility criteria. Outcomes were synthesized systematically, and meta-analyses were performed to estimate standardized mean differences (SMDs) in interferon-gamma (IFNγ) levels, and IFNγ positive immune cells between individuals with LTBI and active TB patients. Results Twenty-six studies (1278 individuals with LTBI and 1189 active TB patients) were included. DosR antigens Rv0569 (Standardized mean difference; SMD 2.44 [95%CI: 1.21, 3.66]; p

Abstract Background Recent articles have explored the effect of worms on cancer cells. This review focused on various cell cultures employed to understand which cells are more commonly and less utilized. Methods The present review analyzed studies published between 2013 and 2023 to obtain information about different cell cultures used in cancer studies involving helminths. Databases such as PubMed, Google Scholar, HINARI, and the Cochrane Library were searched. Results This search yielded 130 records, but 97 papers were excluded because they were either irrelevant to the research topic (n = 72) or contradicted the research idea (n = 25).The remaining twenty-one articles focused on different types of worms, such as Echinococcus granulosus, Clonorchis sinensis, Opisthorchis felineus, Opisthorchis viverrini, Trichinella spiralis, Toxocara canis, and Heligmosomoides polygyrus. Conclusion Due to the presence of numerous antigens, parasites at different growth stages can impact various cells through unknown mechanisms. Given the high diversity of antigens and their effects, artificial intelligence can assist in predicting initial outcomes for future studies.

Maize lethal necrosis (MLN) is a maize disease caused by the maize chlorotic mottle virus (MCMV), a potyvirus which causes yield losses of 30–100%. The present study aimed to isolate nanobodies against the MCMV coat protein (CP) for the diagnosis of MLN. MCMV CP expressed in Escherichia coli was used for llama immunization. VHH (i.e. variable heavy domain of heavy chain) gene fragments were prepared from blood drawn from the immunized llama and used to generate a library in E. coli TG1 cells. MCMV specific nanobodies were selected by three rounds of phage display and panning against MCMV CP. The selected nanobodies were finally expressed in E. coli WK6 cells and purified. Eleven MCMV‐specific nanobodies were identified and shown to detect MCMV in infected maize plants. Thus, our results show that nanobodies isolated from llama immunized with MCMV CP can distinguish infected and healthy maize plants, potentially enabling development of affordable MCMV detection protocols.

Autoimmunity is characterized by loss of tolerance to tissue-specific as well as systemic antigens, resulting in complex autoantibody landscapes. Here, we introduce and extensively validate the performance characteristics of a murine proteome-wide library for phage display immunoprecipitation and sequencing (PhIP-seq) in profiling mouse autoantibodies. This library was validated using 7 genetically distinct mouse lines across a spectrum of autoreactivity. Mice deficient in antibody production (Rag2-/- and μMT) were used to model nonspecific peptide enrichments, while cross-reactivity was evaluated using anti-ovalbumin B cell receptor-restricted OB1 mice as a proof of principle. The PhIP-seq approach was then utilized to interrogate 3 distinct autoimmune disease models. First, serum from Lyn-/- IgD+/- mice with lupus-like disease was used to identify nuclear and apoptotic bleb reactivities. Second, serum from nonobese diabetic (NOD) mice, a polygenic model of pancreas-specific autoimmunity, was enriched in peptides derived from both insulin and predicted pancreatic proteins. Lastly, Aire-/- mouse sera were used to identify numerous autoantigens, many of which were also observed in previous studies of humans with autoimmune polyendocrinopathy syndrome type 1 carrying recessive mutations in AIRE. These experiments support the use of murine proteome-wide PhIP-seq for antigenic profiling and autoantibody discovery, which may be employed to study a range of immune perturbations in mouse models of autoimmunity profiling.

The T cell receptor (TCR) complex is a naturally occurring antigen sensor that detects, amplifies and coordinates cellular immune responses to epitopes derived from cell surface and intracellular proteins. Thus, TCRs enable the targeting of proteins selectively expressed by cancer cells, including neoantigens, cancer germline antigens and viral oncoproteins. As such, TCRs have provided the basis for an emerging class of oncology therapeutics. Herein, we review the current cancer treatment landscape using TCRs and TCR-like molecules. This includes adoptive cell transfer of T cells expressing endogenous or engineered TCRs, TCR bispecific engagers and antibodies specific for human leukocyte antigen (HLA)-bound peptides (TCR mimics). We discuss the unique complexities associated with the clinical development of these therapeutics, such as HLA restriction, TCR retrieval, potency assessment and the potential for cross-reactivity. In addition, we highlight emerging clinical data that establish the antitumour potential of TCR-based therapies, including tumour-infiltrating lymphocytes, for the treatment of diverse human malignancies. Finally, we explore the future of TCR therapeutics, including emerging genome editing methods to safely enhance potency and strategies to streamline patient identification.

Transgenic T-cell receptor (TCR) T cell-based adoptive cell therapies for solid tumors are associated with dramatic initial response rates, but there remain many instances of treatment failure and disease relapse. The association of infusion product cytokine profiles with clinical response has not been explored in the context of TCR T-cell therapy products. Single-cell antigen-dependent secretomic and proteomic analysis of preinfusion clinical TCR T-cell therapy products revealed that TNFα cytokine functionality of CD8+ T cells and phospho-STAT3 signaling in these cells were both associated with superior clinical responsiveness to therapy. By contrast, CD4+ T-helper 2 cell cytokine profiles were associated with inferior clinical responses. In parallel, preinfusion levels of IL15, Flt3-L, and CX3CL1 were all found to be associated with clinical response to therapy. These results have implications for the development of therapeutic biomarkers and identify potential targets for enrichment in the design of transgenic TCR T-cell therapies for solid tumors.

Multivalent viral epitopes induce rapid, robust and T cell-independent humoral immune responses, but the biochemical basis for such potency remains incompletely understood. We take advantage of a set of liposomes of viral size engineered to display affinity mutants of the model antigen (Ag) hen egg lysozyme. Particulate Ag induces potent all-or-none B cell responses that are density dependent but affinity independent. Unlike soluble Ag, particulate Ag induces signal amplification downstream of the B cell receptor by selectively evading LYN-dependent inhibitory pathways and maximally activates NF-κB in a manner that mimics T cell help. Such signaling induces MYC expression and enables even low doses of particulate Ag to trigger robust B cell proliferation in vivo in the absence of adjuvant. We uncover a molecular basis for highly sensitive B cell responses to viral Ag display that is independent of encapsulated nucleic acids and is not merely accounted for by avidity and B cell receptor cross-linking.

Abstract Background Enterococcus faecium and Staphylococcus aureus are the Gram-positive pathogens of the ESKAPE group, known to represent a great threat to human health due to their high virulence and multiple resistances to antibiotics. Combined, enterococci and S. aureus account for 26% of healthcare-associated infections and are the most common organisms responsible for blood stream infections. We previously showed that the peptidyl-prolyl cis/trans isomerase (PPIase) PpiC of E. faecium elicits the production of specific, opsonic, and protective antibodies that are effective against several strains of E. faecium and E. faecalis. Due to the ubiquitous characteristics of PPIases and their essential function within Gram-positive cells, we hypothesized a potential cross-reactive effect of anti-PpiC antibodies. Results Opsonophagocytic assays combined with bioinformatics led to the identification of the foldase protein PrsA as a new potential vaccine antigen in S. aureus. We show that PrsA is a stable dimeric protein able to elicit opsonic antibodies against the S. aureus strain MW2, as well as cross-binding and cross-opsonic in several S. aureus, E. faecium and E. faecalis strains. Conclusions Given the multiple antibiotic resistances S. aureus and enterococci present, finding preventive strategies is essential to fight those two nosocomial pathogens. The study shows the potential of PrsA as an antigen to use in vaccine formulation against the two dangerous Gram-positive ESKAPE bacteria. Our findings support the idea that PPIases should be further investigated as vaccine targets in the frame of pan-vaccinomics strategy.

Abstract Background Neoadjuvant chemotherapy followed by interval debulking surgery is currently a common treatment option for advanced epithelial ovarian cancer (EOC). The Standardized CA-125 ELIMination rate constant K (Std KELIM) and the Platinum Resistant Recurrence (PtRR) Score have been proposed as markers of tumor chemosensitivity. The aim of our study was to validate these tools for predicting platinum sensitivity in a real-world population of patients with advanced EOC treated with neoadjuvant chemotherapy. Experimental design All patients with advanced EOC treated with neoadjuvant chemotherapy at the Institut Curie between 2000 and 2015 were included. The Std KELIM was calculated with the CA-125 concentrations during the first 100 days of chemotherapy. The predictive value of Std KELIM and PtRR scores for the risk of subsequent PtRR was assessed using receiver operating characteristic (ROC) curve analysis, logistic regression and calibration curve. Kaplan–Meier survival analysis was performed for the treatment-free interval from platinum (TFIp) therapy and overall survival (OS). Results Std KELIM data were available for 149 patients. The AUC was 0.67 for PtRR. A low Std KELIM was significantly associated with PtRR (OR = 0.19 (95% CI [0.06, 0.53], p = 0.002)) according to the univariate analysis. The calibration curve of the PtRR showed a slight but significant underestimation (p = 0.02) of the probability of platinum resistance. Favorable Std KELIM (≥ 1) alone and combined with the completeness of surgery were associated with significantly better survival in terms of TFIp and OS. Conclusions Std KELIM is an early prognostic marker of chemosensitivity in a real-life setting complementary to surgical status. It could help the clinician in the early management of patients by identifying those with a worse prognosis.

Background and Aim: Although reverse zoonotic transmission events from humans to domestic cats have been described, there is currently little evidence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) circulation in stray cats. Due to the evidence of natural and experimental infections in cats and the capacity to disseminate the virus among them, this study aimed to identify the SARS-CoV-2 antigen in stray cats from the Federal University of Sergipe in Brazil. Materials and Methods: One hundred twenty six stray cats from the university were screened for SARS-CoV-2 antigens by random sampling. Throat swab samples were tested for the virus using rapid antigen detection tests. Results: Of the 126 animals tested, 30 (23.60%) were positive for SARS-CoV-2 antigens. To our knowledge, for the first time, this study detected the SARS-CoV-2 antigen in stray cats and confirmed the presence of SARS-CoV-2 infections in Brazil’s stray cat population. Conclusion: The detection of SARS-CoV-2 in stray cats poses a risk for infected and healthy animals and possibly for humans who attend the university daily. As a limitation of the study, the small sample size necessitates caution when interpreting the results. This underscores the need for further research in this area to help control diseases in stray animals during potential pandemics. This highlights the need for monitoring and controlling the spread of the virus in stray animal populations.

AbstractImmunoassays based on the specific antigen—antibody interactions are efficient tools to detect various compounds and estimate their content. Usually, these assays are implemented in water-saline media with composition close to physiological conditions. However, many substances are insoluble or cannot be molecularly dispersed in such media, which objectively creates problems when interacting in aquatic environments. Thus, obtaining immunoreactants and implementing immunoassays of these substances need special methodological solutions. Hydrophobicity of antigens as well as their limited ability to functionalization and conjugation are often overlooked when developing immunoassays for these compounds. The main key finding is the possibility to influence the behavior of hydrophobic compounds for immunoassays, which requires specific approaches summarized in the review. Using the examples of two groups of compounds—surfactants (alkyl- and bisphenols) and fullerenes, we systematized the existing knowledge and experience in the development of immunoassays. This review addresses the challenges of immunodetection of poorly soluble substances and proposes solutions such as the use of hydrotropes, other solubilization techniques, and alternative receptors (aptamers and molecularly imprinted polymers). [ABSTRACT FROM AUTHOR]

A current study objective was to investigate the effect of maternal immunization during the period of collecting eggs for hatching on maternal immunity transmitted to their chicks at two weeks of age. The total number of chicks was 180 used from thirty-two hens. Hens were divided into three segments according to antibody titer of SRBCs (high, medium, and low) segments. The resulting fertilized eggs were divided into two groups (Group1 and Group2) based on the period of egg collection after maternal SRBCs antigen injection. The obtained results were: 1.The transfer percentages for the three segments (high, medium, and low) were 2.88, 5.56, and 60.74%, respectively. Here we notice a clear inverse relationship between the level of maternal antibodies and the remaining percentage of immunity transmitted to the chicks at two weeks of age. Where, the transfer percentages for two separate groups (group1 and group2) were 1.48, and 12.65%, respectively. This means that the second group is higher than the first group in the transfer percentage of remaining maternal antibodies at two weeks old chicks. 2.There were significant differences between dams’ antibody titers to SRBCs antigen means, whether in the three segments (high, medium, and low) and, between the two groups. 3.There was a significant interaction between both segments (high, medium, and low) and groups (group1 and group2). In antibody titers to SRBCs antigen means of dams and antibody titers to SRBCs antigen transformed means in two-week chicks old of dams for two-week-old chicks, but there were no significant differences between segments (high, medium, and low) in antibody titers to SRBCs antigen transformed means in two-week chicks. [ABSTRACT FROM AUTHOR]

The common use of antimicrobials in food-animal production can lead to drug residues in edible tissues for consumers. However, immunomodulators enhance immune responses and vaccine effectiveness. A new perspective explores bacterial extracellular bioactive molecules (EBMs) in food-animal production to modulate host immune responses, potentially transforming pathogen management and antimicrobial use. This study investigates the immunogenic potential of Aeromonas hydrophila-derived EBMs (Antigens) to enhance the immune system. Four Antigens were administered intraperitoneally to Oreochromis niloticus (Nile Tilapia). Antigens 2 and Antigens 3 boosted fish immune competence within 21 days. Remarkably, Antigens 3 induced robust immunity against A. hydrophila with a single dose, notably enhancing antibody-based immune responses. The increased antibody activity suggests Antigens 3 could be a vaccine candidate, promising further research and potential application in food-animal production to improve disease control. This study highlights immunomodulators' potential in reshaping disease management in the food-animal industry, emphasizing the benefits of focusing on bacterial EBMs to reduce reliance on antimicrobials and achieve sustainable disease prevention. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We have undertaken this review to explore the various developments and insights of CAR-T cell therapy during 1989-2023 and its advantages in the treatment of cancer and immune modulation. It is a chimeric antigen receptor T-cell therapy, which is an innovative form of immunotherapy that harnesses the power of the immune system to fight cancer. At first, T cells are extracted from the patient's blood through a process called leukapheresis. Then the modification has been done in T cells by genetically engineered to express chimeric antigen receptors (CARs) on their surface. These receptors are designed to recognize specific proteins, or antigens, that are found on the surface of cancer cells. Many conventional therapies available in the market for the treatment of cancer and Immuno modulation but most of them having Adverse Drug Reaction (ADR). But CAR-T cells possess upper hand on these conventional Formulations. Once a sufficient number of CAR-T cells have been produced, they are infused back into the patient's bloodstream. Once reach inside the body, the CAR-T cells recognize and bind to the cancer cells that express the specific antigen targeted by the CAR. This triggers the destruction of the cancer cells by the immune system. CAR-T cell therapy has shown remarkable success in treating certain types of blood cancers, such as acute lymphoblastic leukaemia (ALL), chronic lymphocytic leukaemia (CLL), and certain types of lymphoma. The content of this review will pave the way to work on CAR-T cell therapy. [ABSTRACT FROM AUTHOR]