Antibodies最新文献

Background: The presence of intrathecal total IgG production is a hallmark of cerebrospinal fluid (CSF) characteristics in multiple sclerosis (MS). Herein, we systematically analyze how the intensity (instead of mere presence) of intrathecal total IgG production relates to basic CSF parameters in MS.

Methods: We retrospectively assessed clinical routine CSF findings from 390 therapy-naïve relapsing-remitting MS patients diagnosed according to 2017 revised McDonald criteria. The intensity of intrathecal total IgG synthesis according to Reiber's formula was stratified and correlated to demographics, CSF white cell count (WCC), and diversity of MRZ reaction, defined as a polyspecific intrathecal production of IgG reactive against ≥2 of the 3 viruses; measles (M), rubella (R), and varicella zoster (Z) virus.

Results: The higher intensity of intrathecal total IgG production significantly correlated with higher CSF WCC (Spearman's ρ = 0.433, p < 0.001) and with the increasing presence and diversity of positive MRZ reaction (Spearman's ρ = 0.600, p < 0.001). Female patients showed higher intensity of intrathecal total IgG production and higher prevalence of positive MRZ reaction than males.

Conclusions: The intensity of intrathecal total IgG production correlates with the degree of CSF WCC and diversity of MRZ reaction in MS. As yet unidentified female sex-related factors increase the intensity and diversity of intrathecal IgG production in MS.

Background: Immune correlates of protection are ideal tools to predict treatment or vaccine efficacy. However, the accuracy of the immune correlate and the capability to robustly predict the outcome of a vaccine candidate are determined by the performance of the in vitro immunoassay used. Several Theileria parva sporozoite seroneutralization assays have previously been used to assess antibody functional activities; however, a common limitation has been the need for fresh material, target cells and sporozoites, and operator-to-operator bias. An improved assay represents a positive step toward overcoming challenges associated with variability and it might provide a more reliable means of establishing an immune correlate with protection after sub-unit vaccine administration.

Methods: Herein, we describe key improvements, among them, (1) the use of frozen parasites and target cells to avoid batch-to-batch variations and (2) the development of a new assay read-out based on the detection of infected cells through flow cytometry, instead of the use of Giemsa staining and microscopic evaluation, in order to improve the reproducibility of the results.

Results: The improved seroneutralization assay is not only able to detect the individual neutralizing capacity of antibodies; it also detects the additive effect of antibody combinations.

Conclusions: This effect is described for the first time in Theileria parva and is of great interest for new antigen discovery and/or the epitope discovery of already known antigens like p67, opening a new avenue for the identification of ECF immune correlates of protection and the in vitro down-selection of new Theileria parva vaccine candidates, thereby contributing to reducing the use of animals in challenge experiments.

Background/objectives: Anterior Gradient-2 (AGR2/PDIA17) is a member of the protein disulfide isomerase (PDI) family of oxidoreductases. AGR2 is up-regulated in several solid tumors, including pancreatic ductal adenocarcinoma (PDAC). Given the dire need for new therapeutic options for PDAC patients, we investigated the expression and function of AGR2 in PDAC and developed a novel series of affinity-matured AGR2-specific single-chain variable fragments (scFvs) and monoclonal antibodies.

Results: We found that AGR2 was expressed in approximately 90% of PDAC but not normal pancreas biopsies, and the level of AGR2 expression correlated with increasing disease stage. AGR2 expression was inversely related to SMAD4 status in PDAC and colorectal cancer cell models and was secreted from cells into their media. In normal tissues, a high density of AGR2 was detected in the epithelium of cells in the digestive tract but was lacking in most other normal tissue systems. The addition of recombinant AGR2 to cell culture and genetic overexpression of AGR2 increased the adhesion, motility, and invasiveness of both human and mouse PDAC cells. Human phage display library screening led to the discovery of multiple AGR2-specific scFv clones that were affinity-matured to produce monoclonal antibody (MAb) clones with low picomolar binding affinity (S31R/A53F/Y). These high-affinity MAbs inhibited AGR2-mediated cell adhesion, migration, and binding to LYPD3, which is a putative cell surface binding partner of AGR2.

Conclusions: Our study provides novel, high-affinity, fully human, anti-AGR2 MAbs that neutralize the pro-tumor effects of extracellular AGR2 in PDAC.

Background: The complementarity-determining region (CDR) of antibodies represents the most diverse region both in terms of sequence and structural characteristics, playing the most critical role in antibody recognition and binding for immune responses. Over the past decades, several numbering schemes have been introduced to define CDRs based on sequence. However, the existence of diverse numbering schemes has led to potential confusion, and a comprehensive evaluation of these schemes is lacking.

Methods: We employ statistical analyses to quantify the diversity of CDRs compared to the framework regions.

Results: Comparative analyses across different numbering schemes demonstrate notable variations in CDR definitions. The Kabat and AbM numbering schemes tend to incorporate more conserved residues into their CDR definitions, whereas CDRs defined by the Chothia and IMGT numbering schemes display greater diversity, sometimes missing certain loop residues. Notably, we identify a critical residue, L29, within the kappa light chain CDR1, which appears to act as a pivotal structural point within the loop. In contrast, most numbering schemes designate the topological equivalent point in the lambda light chain as L30, suggesting the need for further refinement in the current numbering schemes.

Conclusions: These findings shed light on regional sequence and structural conservation within antibody sequence databases while also highlighting discrepancies stemming from different numbering schemes. These insights yield valuable guidelines for the precise delineation of antibody CDRs and the strategic design of antibody repertoires, with practical implications in developing innovative antibody-based therapeutics and diagnostics.

Background: B-cell maturation antigen (BCMA)-targeted T cell-redirecting immunotherapies, including Chimeric Antigen Receptor (CAR) T-cell therapy and T-cell engagers have demonstrated remarkable success in treating relapsed/refractory (RR) multiple myeloma (MM), a malignancy of plasma cells. However, a significant challenge is the severe side effects associated with T-cell overactivation, leading to cytokine release syndrome and neurotoxicity in MM patients undergoing such therapies. Bispecific NK cell engagers (NKCEs) may offer a promising alternative by redirecting NK cell cytotoxic activity towards tumor cells without triggering cytokine release syndrome.

Methods: In this study, we designed a series of BCMA × CD16 NKCEs that simultaneously engage BCMA and CD16 on MM and NK cells, respectively. We evaluated the functionality of these NKCEs in vitro with respect to their molecular design.

Results: Our results indicate that the format design of NKCEs influences their functionalities, underscoring the importance of format selection in optimizing NKCE-based therapies for MM. This study provides valuable insights for developing next-generation NKCEs and advancing therapeutic strategies for MM and potentially other malignancies.

Background/objectives: Salivary immunoglobulin A (IgA) is a mediator of local immunity and host defence. Altered IgA levels may predispose to bacterial invasion of the mucosa in the gastrointestinal tract, including the oral cavity. Our study aimed to present the diagnostic trends related to salivary IgA in health and disease based on a bibliometric analysis of published papers between 2009 and 2024.

Methods: By 14 September 2024, 1247 English original articles were found in the database Web of Science. We selected 838 records considering the diagnostic usefulness of IgA in human subjects. Based on bibliographic data, we created citation and keyword co-occurrence maps using VOSviewer 1.6.20.

Results: Most articles belonged to the "Sport Sciences" category (n = 169), followed by the "Immunology" category (n = 93). The Brazilian researcher Alexandre Moreira from the University of Sao Paulo had the most published and most frequently cited papers. Most of the included articles came from the USA (n = 158), England (n = 105), Brazil (n = 95), and Japan (n = 95). The most cited article described research on IgA in response to SARS-CoV-2 infection (n = 690), but the subsequent two papers considered the role of salivary IgA in the dysbiosis of the intestinal microbiota in inflammatory bowel diseases (n = 272) and the formation of systemic immune responses from the gastrointestinal tract (n = 245).

Conclusions: Salivary IgA is a widely evaluated diagnostic marker in both patients and healthy individuals. Numerous reports have identified its changes as a result of physical exertion in various groups of athletes, during infections (including SARS-CoV-2) and in the course of local diseases (e.g., periodontal disease) or systemic diseases (e.g., inflammatory bowel disease).

Background/objectives: In a previous study, we described elevated anti-Anisakis IgG levels in septic patients in relation to disease severity. In this study, our objective was to analyze the evolution of anti-Anisakis immunoglobulins in septic patients during hospital admission and their association with αβ and γδ T cell subsets.

Methods: We recruited 80 subjects: 40 patients with sepsis and 40 controls. αβ and γδ T cells were analyzed using flow cytometry. Apoptosis was also assessed, and anti-Anisakis antibodies were measured by ELISA in the sera of patients with sepsis and controls.

Results: In the second analysis (7-10 after sepsis evolution), an increase in all specific antibody isotypes was identified in individuals with septic shock, except IgE. The levels of anti-Anisakis IgG and IgA were higher in the subjects with sepsis in the first analysis and continued to increase in the second analysis compared with the healthy control subjects. There was an increase in anti-Anisakis IgG and IgA levels in surviving patients and an increase in IgA levels in non-surviving patients. A rise in specific IgG and IgE levels was noted in the second analysis of patients with sepsis with αβ CD3+ T cell deficiency. Patients without γδ T cell deficiency had increased anti-Anisakis IgA levels 7-10 days after admission.

Conclusions: Our results suggest a previous infection by Anisakis that could be involved in the subsequent septic process and be related to patients who have negative cultures in which the pathogen causing sepsis has not been identified.

Paraneoplastic pemphigus (PNP) is a rare autoimmune disorder associated with underlying neoplasms, predominantly Non-Hodgkin Lymphomas, affecting adults aged 45 to 70. This review analyzed 87 articles from MEDLINE/PubMed, Ovid and Scopus focusing on patients with oral manifestations of PNP, emphasizing histological and serological aspects and discussing recent updates on pathogenetic options. Key findings revealed that PNP is often diagnosed before the neoplasm, with Follicular variant Non-Hodgkin Lymphoma and Castleman Disease being the most common associations. Histopathological analysis showed suprabasal acantholysis and inflammation, and serological tests identify a comprehensive autoantibody panel, underscoring the need for standardized diagnostic criteria and improved serological testing.

Background: Although immune checkpoint inhibitors (ICIs) have demonstrated efficacy in treating advanced cancers, their therapeutic success remains limited for many patients, with initial responders often experiencing resistance and relapse. Interleukin-12 (IL-12) is a powerful cytokine for antitumor immunotherapy, enhancing both lymphocyte recruitment into tumors and immune cell activation. Methods: In this study, we successfully produced mouse interleukin-12 (mIL12) through eukaryotic recombinant expression. In vivo, mIL12 exhibited significant control of tumor immunity in ICI-resistant and aggressive tumor models. Further mechanistic analysis indicated that treatment with mIL12 led to a substantial increase in tumor-infiltrating CD4⁺ T, CD8⁺ T, cDC1, and CD103⁺ cDC1 cells. Results: Our data underscore the potential of a combined therapeutic strategy involving IL-12 with PD-1 and CTLA-4 blockade to elicit a potent antitumor immune response. Notably, the co-administration of mIL12 and PD-1 blockade significantly enhanced the presence of central memory T cells (T_CM) within tumors. Conclusions: This study is the first to provide evidence that the combination of mIL12 and PD-1 blockers promotes the generation of T_CM, potentially contributing to a robust and durable antitumor effect.

Immuno-oncology has revolutionized cancer treatment, with NKG2A emerging as a novel target for immunotherapy. The blockade of NKG2A using the immune checkpoint inhibitor (ICI) monalizumab has been shown to enhance the responses of both NK cells and CD8+ T cells. However, monalizumab has demonstrated limited efficacy in in vitro cytotoxic assays and clinical trials. In our study, we discovered and characterized a novel anti-NKG2A antibody, BRY805, which exhibits high specificity for the human CD94/NKG2A heterodimer complex and does not bind to the activating NKG2C receptor. In vitro cytotoxicity assays demonstrated that BRY805 effectively activated NK92 cells and primary NK cells, thereby enhancing the cytotoxic activity of effector cells against cancer cells overexpressing HLA-E, with significantly greater efficacy compared to monalizumab. Furthermore, BRY805 exhibited synergistic antitumor activity when combined with PD-L1 monoclonal antibodies. In a mouse xenograft model, BRY805 showed superior tumor control relative to monalizumab and demonstrated a favorable safety profile in non-human primate studies.