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Nature Communications Apr 2023During an infection the immune system produces pathogen-specific antibodies. These antibody repertoires become specific to the history of infections and represent a rich...
During an infection the immune system produces pathogen-specific antibodies. These antibody repertoires become specific to the history of infections and represent a rich source of diagnostic markers. However, the specificities of these antibodies are mostly unknown. Here, using high-density peptide arrays we examined the human antibody repertoires of Chagas disease patients. Chagas disease is a neglected disease caused by Trypanosoma cruzi, a protozoan parasite that evades immune mediated elimination and mounts long-lasting chronic infections. We describe a proteome-wide search for antigens, characterised their linear epitopes, and show their reactivity on 71 individuals from diverse human populations. Using single-residue mutagenesis we revealed the core functional residues for 232 of these epitopes. Finally, we show the diagnostic performance of identified antigens on challenging samples. These datasets enable the study of the Chagas antibody repertoire at an unprecedented depth and granularity, while also providing a rich source of serological biomarkers.
Topics: Humans; Trypanosoma cruzi; Epitopes; Antibody Specificity; Enzyme-Linked Immunosorbent Assay; Chagas Disease; Antigens, Protozoan; Antibodies; Americas; Antibodies, Protozoan
PubMed: 37012236
DOI: 10.1038/s41467-023-37522-9 -
Papillomavirus Research (Amsterdam,... Dec 2019Human papillomavirus (HPV) infects and propagates in the cervical mucosal epithelium. Hence, in addition to assessing systemic immunity, the accurate measurement of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Human papillomavirus (HPV) infects and propagates in the cervical mucosal epithelium. Hence, in addition to assessing systemic immunity, the accurate measurement of cervical immunity is important to evaluate local immune responses to HPV infection and vaccination. This review discusses studies that investigated the presence of infection and vaccine-induced HPV-specific antibodies in cervicovaginal secretions (CVS).
METHODS
We searched the two main health sciences databases, PubMed and the ISI Web of Science, from the earliest dates available to March 2019. From the eligible publications, information was extracted regarding: (i) study design, (ii) the reported HPV-specific antibody concentrations in CVS (and the associated serum levels, when provided), (iii) the CVS collection method, and (iv) the immunoassays used.
RESULTS
The systematic search and selection process yielded 44 articles. The evidence of HPV-specific antibodies in CVS after natural infection (26/44) and HPV vaccination (18/44) is discussed. Many studies indicate that HPV-specific antibody detection in CVS is variable but feasible with a variety of collection methods and immunoassays. Most CVS samples were collected by cervicovaginal washing or wicks, and antibody presence was mostly determined by VLP-based ELISAs. The moderate to strong correlation between vaccine-induced antibody levels in serum and in CVS indicates that HPV vaccines generate antibodies that transudate through the cervical mucosal epithelium.
CONCLUSION
Although HPV-specific antibodies have lower titres in CVS than in serum samples, studies have shown that their detection in CVS is feasible. Nevertheless, the high variability of published observations and the lack of a strictly uniform, well-validated method for the collection, isolation and quantification of antibodies indicates a need for specific methods to improve and standardize the detection of HPV-specific antibodies in CVS.
Topics: Antibodies, Viral; Antibody Specificity; Cervix Uteri; Female; Host-Pathogen Interactions; Humans; Immunity, Mucosal; Papillomaviridae; Papillomavirus Infections; Papillomavirus Vaccines; Vaccination; Vagina
PubMed: 31494291
DOI: 10.1016/j.pvr.2019.100185 -
Molecular Endocrinology (Baltimore, Md.) Sep 2014
Topics: Animals; Antibodies; Antibody Specificity; DNA; Databases, Factual; False Positive Reactions; Humans; Reproducibility of Results; Sensitivity and Specificity
PubMed: 25184858
DOI: 10.1210/me.2014-1230 -
Nature Communications May 2022The antibody response magnitude and kinetics may impact clinical severity, serological diagnosis and long-term protection of COVID-19, which may play a role in why...
The antibody response magnitude and kinetics may impact clinical severity, serological diagnosis and long-term protection of COVID-19, which may play a role in why children experience lower morbidity. We therefore tested samples from 122 children in Hong Kong with symptomatic (n = 78) and asymptomatic (n = 44) SARS-CoV-2 infections up to 200 days post infection, relative to 71 infected adults (symptomatic n = 61, and asymptomatic n = 10), and negative controls (n = 48). We assessed serum IgG antibodies to a 14-wide antigen panel of structural and accessory proteins by Luciferase Immuno-Precipitation System (LIPS) assay and circulating cytokines. Infected children have lower levels of Spike, Membrane, ORF3a, ORF7a, ORF7b antibodies, comparable ORF8 and elevated E-specific antibodies than adults. Combination of two unique antibody targets, ORF3d and ORF8, can accurately discriminate SARS-CoV-2 infection in children. Principal component analysis reveals distinct pediatric serological signatures, and the highest contribution to variance from adults are antibody responses to non-structural proteins ORF3d, NSP1, ORF3a and ORF8. From a diverse panel of cytokines that can modulate immune priming and relative inflammation, IL-8, MCP-1 and IL-6 correlate with the magnitude of pediatric antibody specificity and severity. Antibodies to SARS-CoV-2 internal proteins may become an important sero surveillance tool of infection with the roll-out of vaccines in the pediatric population.
Topics: Adult; Antibody Specificity; COVID-19; Child; Cytokines; Humans; Immunoglobulin G; SARS-CoV-2
PubMed: 35618731
DOI: 10.1038/s41467-022-30699-5 -
Advances in Experimental Medicine and... 2017Historically, serum therapy was previously used to combat infectious pathogens. However, serum sickness and anaphylaxis limited its broad application. The advancement of... (Review)
Review
Historically, serum therapy was previously used to combat infectious pathogens. However, serum sickness and anaphylaxis limited its broad application. The advancement of antibody engineering technologies has made it feasible to generate monoclonal antibodies. There are divergent methods for antibody engineering and optimization. In this chapter, we summarized the latest developments in engineering antibodies for infectious diseases.
Topics: Animals; Anti-Infective Agents; Antibodies; Antibody Specificity; Communicable Diseases; Humans; Protein Engineering
PubMed: 29549641
DOI: 10.1007/978-3-319-72077-7_10 -
Frontiers in Immunology 2018Immunoglobulin E (IgE)-associated allergy is the most common immunologically-mediated hypersensensitivity disease. It is based on the production of IgE antibodies and T... (Review)
Review
Immunoglobulin E (IgE)-associated allergy is the most common immunologically-mediated hypersensensitivity disease. It is based on the production of IgE antibodies and T cell responses against innocuous antigens (i.e., allergens) and subsequent allergen-induced inflammation in genetically pre-disposed individuals. While allergen exposure in sensitized subjects mainly boosts IgE production and T cell activation, successful allergen-specific immunotherapy (AIT) induces the production of allergen-specific IgG antibodies and reduces T cell activity. Under both circumstances, the resulting allergen-antibody complexes play a major role in modulating secondary allergen-specific immune responses: Allergen-IgE complexes induce mast cell and basophil activation and perpetuate allergen-specific T cell responses via presentation of allergen by allergen presenting cells to T cells, a process called IgE-facilitated antigen presentation (FAP). In addition, they may induce activation of IgE memory B cells. Allergen-induced production of specific IgGs usually exerts ameliorating effects but under certain circumstances may also contribute to exacerbation. Allergen-specific IgG antibodies induced by AIT which compete with IgE for allergen binding (i.e., blocking IgG) inhibit formation of IgE-allergen complexes and reduce activation of effector cells, B cells and indirectly T cells as FAP is prevented. Experimental data provide evidence that by binding of allergen-specific IgG to epitopes different from those recognized by IgE, allergen-specific IgG may enhance IgE-mediated activation of mast cells, basophils and allergen-specific IgE B cells. In this review we provide an overview about the role of allergen-specific antibodies in regulating secondary allergen-specific immune responses.
Topics: Allergens; Animals; Antibodies; Antibodies, Blocking; Antibody Specificity; Antigen Presentation; Antigen-Presenting Cells; B-Lymphocytes; Desensitization, Immunologic; Epitopes; Humans; Hypersensitivity; Immunity; Immunoglobulin E; Immunologic Memory; Lymphocyte Activation; Seasons; T-Lymphocytes
PubMed: 30705676
DOI: 10.3389/fimmu.2018.03131 -
American Journal of Hematology Apr 2015Anti-human leukocyte antigens (HLA) antibodies can adversely impact the care of hematology patients. In particular, HLA antibody testing provides important information... (Review)
Review
Anti-human leukocyte antigens (HLA) antibodies can adversely impact the care of hematology patients. In particular, HLA antibody testing provides important information for optimal stem cell and platelet donor selection in the management of stem cell recipients and platelet refractory patients. Current testing methods for HLA antibodies are briefly reviewed, with particular emphasis on laboratory and clinical issues associated with solid-phase multiplex assays.
Topics: Antibody Specificity; Enzyme-Linked Immunosorbent Assay; Flow Cytometry; HLA Antigens; Hematologic Diseases; Hematopoietic Stem Cell Transplantation; Histocompatibility Testing; Humans; Isoantibodies
PubMed: 25580568
DOI: 10.1002/ajh.23935 -
Bioinformatics (Oxford, England) Jul 2023While antibodies have been ground-breaking therapeutic agents, the structural determinants for antibody binding specificity remain to be fully elucidated, which is...
MOTIVATION
While antibodies have been ground-breaking therapeutic agents, the structural determinants for antibody binding specificity remain to be fully elucidated, which is compounded by the virtually unlimited repertoire of antigens they can recognize. Here, we have explored the structural landscapes of antibody-antigen interfaces to identify the structural determinants driving target recognition by assessing concavity and interatomic interactions.
RESULTS
We found that complementarity-determining regions utilized deeper concavity with their longer H3 loops, especially H3 loops of nanobody showing the deepest use of concavity. Of all amino acid residues found in complementarity-determining regions, tryptophan used deeper concavity, especially in nanobodies, making it suitable for leveraging concave antigen surfaces. Similarly, antigens utilized arginine to bind to deeper pockets of the antibody surface. Our findings fill a gap in knowledge about the antibody specificity, binding affinity, and the nature of antibody-antigen interface features, which will lead to a better understanding of how antibodies can be more effective to target druggable sites on antigen surfaces.
AVAILABILITY AND IMPLEMENTATION
The data and scripts are available at: https://github.com/YoochanMyung/scripts.
Topics: Complementarity Determining Regions; Antibodies; Antigens; Antibody Specificity; Binding Sites, Antibody
PubMed: 37382557
DOI: 10.1093/bioinformatics/btad392 -
American Journal of Physiology. Cell... Mar 2015The development of the immunoblot to detect and characterize a protein with an antisera, even in a crude mixture, was a breakthrough with wide-ranging and unpredictable... (Review)
Review
The development of the immunoblot to detect and characterize a protein with an antisera, even in a crude mixture, was a breakthrough with wide-ranging and unpredictable applications across physiology and medicine. Initially, this technique was viewed as a tool for qualitative, not quantitative, analyses of proteins because of the high number of variables between sample preparation and detection with antibodies. Nonetheless, as the immunoblot method was streamlined and improved, investigators pushed it to quantitate protein abundance in unpurified samples as a function of treatment, genotype, or pathology. This short review, geared at investigators, reviewers, and critical readers, presents a set of issues that are of critical importance for quantitative analysis of protein abundance: 1) Consider whether tissue samples are of equivalent integrity and assess how handling between collection and assay influences the apparent relative abundance. 2) Establish the specificity of the antiserum for the protein of interest by providing clear images, molecular weight markers, positive and negative controls, and vendor details. 3) Provide convincing evidence for linearity of the detection system by assessing signal density as a function of sample loaded. 4) Recognize that loading control proteins are rarely in the same linear range of detection as the protein of interest; consider protein staining of the gel or blot. In summary, with careful attention to sample integrity, antibody specificity, linearity of the detection system, and acceptable loading controls, investigators can implement quantitative immunoblots to convincingly assess protein abundance in their samples.
Topics: Animals; Antibody Specificity; Biomarkers; Blotting, Western; Calibration; Humans; Linear Models; Proteins; Reference Standards; Reproducibility of Results; Specimen Handling
PubMed: 25540176
DOI: 10.1152/ajpcell.00400.2014 -
American Journal of Physiology.... Nov 2015
Topics: Animals; Antibodies; Antibody Specificity; Biomedical Research; Gastroenterology; Humans; Immunologic Techniques; Reproducibility of Results
PubMed: 26381706
DOI: 10.1152/ajpgi.00312.2015