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Toxins Sep 2022Ustilaginoidins are a class of bis-naphtho-γ-pyrone mycotoxins produced by the pathogen of rice false smut, which has recently become one of the most devastating...
Ustilaginoidins are a class of bis-naphtho-γ-pyrone mycotoxins produced by the pathogen of rice false smut, which has recently become one of the most devastating diseases in rice-growing regions worldwide. In this research, the nanobody phage display library was established after an alpaca was immunized with the hemiustilaginoidin F-hapten coupled with bovine serum albumin (BSA). Heterologous antigen selection and combing trypsin with competition alternant elution methods were performed for nanobody screening. Two nanobodies, namely, Nb-B15 and Nb-C21, were selected for the establishment of indirect competitive enzyme-linked immunosorbent assays (ic-ELISAs). For Nb-B15 and Nb-C21, their IC values were 11.86 μg/mL and 11.22 μg/mL, and the detection ranges were at 3.41-19.98 μg/mL and 1.17-32.13 μg/mL, respectively. Two nanobodies had a broad spectrum to quantify the contents of total ustilaginoidins in rice samples according to cross-reactivity. The recognition mechanisms of Nb-B15 and Nb-C21 against ustilaginoidin A were elucidated by molecular modeling and docking. The key amino acid sites for the binding of Nb-B15 or Nb-C21 to ustilaginoidin A were mainly located in the FR1 and CDR1 regions. As Nb-B15 was superior to Nb-C21 in the aspects of protein expression, ELISA titer, and tolerance to organic solvents, it was selected for application in the detection of actual contaminated rice samples. The total ustilaginoidin contents of rice samples were analyzed by Nb-B15-based ic-ELISA and HPLC-DAD, between which the results were found to be consistent. The developed immunoassay based on the nanobody from the alpaca can be employed as a rapid and effective method for detection of total utilaginoidins in contaminated rice samples.
Topics: Animals; Oryza; Pyrones; Single-Domain Antibodies; Camelids, New World; Serum Albumin, Bovine; Trypsin; Mycotoxins; Immunoassay; Enzyme-Linked Immunosorbent Assay; Solvents; Haptens; Amino Acids; Antigens, Heterophile
PubMed: 36287930
DOI: 10.3390/toxins14100659 -
Human Immunology Jan 2023Antibody-mediated rejection is a major cause of graft injury and contributes to failure of pig xenografts in nonhuman primates (NHPs). Most 'natural' or elicited... (Review)
Review
BACKGROUND
Antibody-mediated rejection is a major cause of graft injury and contributes to failure of pig xenografts in nonhuman primates (NHPs). Most 'natural' or elicited antibodies found in humans and NHPs are directed against pig glycan antigens, but antibodies binding to swine leukocyte antigens (SLA) have also been detected. Of clinical importance is (i) whether the presence of high levels of antibodies directed towards human leukocyte antigens (HLA) (i.e., high panel-reactive antibodies) would be detrimental to the outcome of a pig organ xenograft; and (ii) whether, in the event of sensitization to pig antigens, a subsequent allotransplant would be at increased risk of graft failure due to elicited anti-pig antibodies that cross-react with human HLA or other antigens.
SUMMARY
A literature review of pig-to-primate studies indicates that relatively few highly-HLA-sensitized humans have antibodies that cross-react with pigs, predicting that most would not be at increased risk of rejecting an organ xenograft. Furthermore, the existing evidence indicates that sensitization to pig antigens will probably not elicit increased alloantibody titers; if so, 'bridging' with a pig organ could be carried out without increased risk of subsequent antibody-mediated allograft failure.
KEY MESSAGE
These issues have important implications for the design and conduct of clinical xenotransplantation trials.
Topics: Animals; Humans; Antigens, Heterophile; Transplantation, Heterologous; Isoantigens; Primates; Antigens; HLA Antigens; Isoantibodies; Graft Rejection
PubMed: 35817653
DOI: 10.1016/j.humimm.2022.06.003 -
Immunology Sep 2013Anti-Gal is the most abundant natural antibody in humans, constituting ~ 1% of immunoglobulins. Anti-Gal is naturally produced also in apes and Old World monkeys. The... (Review)
Review
Anti-Gal is the most abundant natural antibody in humans, constituting ~ 1% of immunoglobulins. Anti-Gal is naturally produced also in apes and Old World monkeys. The ligand of anti-Gal is a carbohydrate antigen called the 'α-gal epitope' with the structure Galα1-3Galβ1-4GlcNAc-R. The α-gal epitope is present as a major carbohydrate antigen in non-primate mammals, prosimians and New World monkeys. Anti-Gal can contributes to several immunological pathogeneses. Anti-Gal IgE produced in some individuals causes allergies to meat and to the therapeutic monoclonal antibody cetuximab, all presenting α-gal epitopes. Aberrant expression of the α-gal epitope or of antigens mimicking it in humans may result in autoimmune processes, as in Graves' disease. α-Gal epitopes produced by Trypanosoma cruzi interact with anti-Gal and induce 'autoimmune like' inflammatory reactions in Chagas' disease. Anti-Gal IgM and IgG further mediate rejection of xenografts expressing α-gal epitopes. Because of its abundance, anti-Gal may be exploited for various clinical uses. It increases immunogenicity of microbial vaccines (e.g. influenza vaccine) presenting α-gal epitopes by targeting them for effective uptake by antigen-presenting cells. Tumour lesions are converted into vaccines against autologous tumour-associated antigens by intra-tumoral injection of α-gal glycolipids, which insert into tumour cell membranes. Anti-Gal binding to α-gal epitopes on tumour cells targets them for uptake by antigen-presenting cells. Accelerated wound healing is achieved by application of α-gal nanoparticles, which bind anti-Gal, activate complement, and recruit and activate macrophages that induce tissue regeneration. This therapy may be of further significance in regeneration of internally injured tissues such as ischaemic myocardium and injured nerves.
Topics: Animals; Antibodies, Heterophile; Autoimmunity; Cancer Vaccines; Chagas Disease; Epitopes; Graves Disease; Humans; Hypersensitivity; Immunity, Innate; Immunoglobulin E; Mammals; Regeneration; Transplantation Immunology; Transplantation, Heterologous; Trisaccharides; Viral Vaccines; Wound Healing
PubMed: 23578170
DOI: 10.1111/imm.12110 -
Archives of Endocrinology and Metabolism Feb 2016Thyroglobulin (Tg) is the major glycoprotein produced by the thyroid gland, where it serves as a template for thyroid hormone synthesis and as an intraglandular store of... (Review)
Review
Insights into the posttranslational structural heterogeneity of thyroglobulin and its role in the development, diagnosis, and management of benign and malignant thyroid diseases.
Thyroglobulin (Tg) is the major glycoprotein produced by the thyroid gland, where it serves as a template for thyroid hormone synthesis and as an intraglandular store of iodine. Measurement of Tg levels in serum is of great practical importance in the follow-up of differentiated thyroid carcinoma (DTC), a setting in which elevated levels after total thyroidectomy are indicative of residual or recurrent disease. The most recent methods for serum Tg measurement are monoclonal antibody-based and are highly sensitive. However, major challenges remain regarding the interpretation of the results obtained with these immunometric methods, particularly in patients with endogenous antithyroglobulin antibodies or in the presence of heterophile antibodies, which may produce falsely low or high Tg values, respectively. The increased prevalence of antithyroglobulin antibodies in patients with DTC, as compared with the general population, raises the very pertinent possibility that tumor Tg may be more immunogenic. This inference makes sense, as the tumor microenvironment (tumor cells plus normal host cells) is characterized by several changes that could induce posttranslational modification of many proteins, including Tg. Attempts to understand the structure of Tg have been made for several decades, but findings have generally been incomplete due to technical hindrances to analysis of such a large protein (660 kDa). This review article will explore the complex structure of Tg and the potential role of its marked heterogeneity in our understanding of normal thyroid biology and neoplastic processes.
Topics: Biomarkers, Tumor; Glycosylation; Halogenation; Humans; Phosphorylation; Protein Processing, Post-Translational; Thyroglobulin; Thyroid Diseases; Thyroid Hormones
PubMed: 26909485
DOI: 10.1590/2359-3997000000103 -
Liver Transplantation and Surgery :... Sep 1995
Topics: Acute Disease; Animals; Animals, Newborn; Antibodies, Heterophile; Graft Rejection; Graft Survival; Heart Transplantation; Humans; Infant, Newborn; Papio; Swine; Transplantation, Heterologous
PubMed: 9346589
DOI: 10.1002/lt.500010508 -
Frontiers in Immunology 2023Microbial infections are associated with the occurrence of autoimmune diseases, but the mechanisms of microbial infection inducing autoimmune diseases are not fully...
INTRODUCTION
Microbial infections are associated with the occurrence of autoimmune diseases, but the mechanisms of microbial infection inducing autoimmune diseases are not fully understood. The existence of heterophilic antigens between microorganisms and human tissues may explain part of the pathogenesis of autoimmune diseases. Here, we investigate the distribution of heterophilic antigens and its relationship with autoimmune diseases.
METHODS
Monoclonal antibodies against a variety of microorganisms were prepared. The titer, subclass and reactivity of antibodies with microorganisms were identified, and heterophilic antibodies that cross-reacted with human tissues were screened by human tissue microarray. The reactivity of these heterophilic antibodies with different individuals and different species was further examined by immunohistochemistry.
RESULTS
In this study, 21 strains of heterophilic antibodies were screened. The results showed that these heterophilic antibodies were produced due to the existence of heterophilic antigens between microorganism and human body and the distribution of heterophilic antigens had individual, tissue and species differences.
CONCLUSION
Our study showed that heterophilic antigens exist widely between microorganisms and human body, and the heterophilic antigens carried by microorganisms may break the immune tolerance of the body through carrier effect and initiate immune response, which may be one of the important mechanisms of infection inducing autoimmune diseases.
Topics: Humans; Antigens, Heterophile; Autoimmune Diseases; Antibodies, Monoclonal; Antibodies, Heterophile; Immunohistochemistry
PubMed: 38022676
DOI: 10.3389/fimmu.2023.1275658 -
Transplantation Dec 2018For a clinical trial today, what might realistically be the optimal pig among those currently available? Deletion of expression of the 3 pig carbohydrate antigens,... (Review)
Review
For a clinical trial today, what might realistically be the optimal pig among those currently available? Deletion of expression of the 3 pig carbohydrate antigens, against which humans have natural (preformed) antibodies (triple-knockout pigs), should form the basis of any clinical trial. However, because both complement and coagulation can be activated in the absence of antibody, the expression of human complement- and coagulation-regulatory proteins is likely to be important in protecting the graft further. Any genetic manipulation that might reduce inflammation of the graft, for example, expression of hemeoxygenase-1 or A20, may also be beneficial to the long-term survival of the graft. The transgene for human CD47 is likely to have a suppressive effect on monocyte/macrophage and T-cell activity. Furthermore, deletion of xenoantigen expression and expression of a human complement-regulatory protein are both associated with a reduced T-cell response. Although there are several other genetic manipulations that may reduce the T-cell response further, it seems likely that exogenous immunosuppressive therapy, particularly if it includes costimulation blockade, will be sufficient. We would therefore suggest that, with our present knowledge and capabilities, the optimal pig might be a triple-knockout pig that expressed 1 or more human complement-regulatory proteins, 1 or more human coagulation-regulatory proteins, a human anti-inflammatory transgene, and CD47. Absent or minimal antibody binding is important, but we suggest that the additional insertion of protective human transgenes will be beneficial, and may be essential.
Topics: Animals; Animals, Genetically Modified; Antigens, Heterophile; Blood Coagulation Factors; CD47 Antigen; Clinical Trials as Topic; Complement System Proteins; Genotype; Graft Rejection; Graft Survival; Heart Transplantation; Humans; Kidney Transplantation; Phenotype; Risk Factors; Sus scrofa; Transplantation Tolerance; Transplantation, Heterologous
PubMed: 30247446
DOI: 10.1097/TP.0000000000002443 -
Cardiology and Therapy Dec 2018In this case report, we describe a young athletic male with a family history of early sudden cardiac death who presented with atypical chest pain and was found to have a...
In this case report, we describe a young athletic male with a family history of early sudden cardiac death who presented with atypical chest pain and was found to have a positive serum troponin. Although his symptoms resolved without intervention, workup revealed hypertension, hyperlipidemia, mild left ventricular hypertrophy, non-obstructive coronary artery disease, and the presence of serum heterophile antibodies. Ultimately, it was concluded that his rigorous exercise regimen as well as the presence of heterophile antibodies may have contributed to his positive serum troponin. This case serves as a reminder of the nonspecific diagnostic value of modern troponin assays, and that the results of these tests should always be incorporated into the clinical context.
PubMed: 30367446
DOI: 10.1007/s40119-018-0120-3 -
Journal of Immunological Methods Aug 2009Immunoassays have made it possible to measure dozens of individual proteins and other analytes in human samples for help in establishing the diagnosis and prognosis of... (Review)
Review
Immunoassays have made it possible to measure dozens of individual proteins and other analytes in human samples for help in establishing the diagnosis and prognosis of disease. In too many cases the results of those measurements are misleading and can lead to unnecessary treatment or missed opportunities for therapeutic interventions. These cases stem from problems inherent to immunoassays performed with human samples, which include a lack of concordance across platforms, autoantibodies, anti-reagent antibodies, and the high-dose hook effect. Tandem mass spectrometry may represent a detection method capable of alleviating many of the flaws inherent to immunoassays. We review our understanding of the problems associated with immunoassays on human specimens and describe methodologies using tandem mass spectrometry that could solve some of those problems. We also provide a critical discussion of the potential pitfalls of novel mass spectrometric approaches in the clinical laboratory.
Topics: Antibodies, Heterophile; Artifacts; Autoantibodies; Biomarkers; Dose-Response Relationship, Immunologic; Humans; Immunoassay; Medical Errors; Predictive Value of Tests; Quality Control; Reproducibility of Results; Tandem Mass Spectrometry; Thyroglobulin
PubMed: 19538965
DOI: 10.1016/j.jim.2009.06.003 -
American Journal of Hematology Aug 2004Infectious mononucleosis (IM) due to all causes is characterized by atypical lymphocytosis. We sought to compare hematologic parameters of infectious mononucleosis due... (Comparative Study)
Comparative Study
Infectious mononucleosis (IM) due to all causes is characterized by atypical lymphocytosis. We sought to compare hematologic parameters of infectious mononucleosis due to Epstein-Barr virus (EBV) infection (heterophile antibody (HA) positive) with mononucleosis due to other causes. Mono-Latex Slide Agglutination Test results and complete blood counts (CBC) of 147 patients with mononucleosis were retrospectively analyzed. Leukocyte count, absolute lymphocyte count, and presence of atypical lymphocytes in EBV-positive and EBV-negative groups were statistically compared. We analyzed 68 EBV-positive and 79 EBV-negative cases. EBV-positive patients were significantly younger than EBV-negative patients were. Mean total WBC count and mean absolute lymphocyte count were significantly higher in EBV-positive patients. Absolute lymphocytosis, absolute leukocytosis, and atypical lymphocytosis were also significantly more frequent in EBV-positive patients. Leukopenia was more frequently seen in EBV-negative patients.
Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Animals; Antibodies, Heterophile; Cattle; Child; Child, Preschool; Cross Reactions; Female; Herpesvirus 4, Human; Humans; Infectious Mononucleosis; Latex Fixation Tests; Leukocyte Count; Leukopenia; Lymphocyte Count; Lymphocytes; Lymphocytosis; Male; Middle Aged; Retrospective Studies
PubMed: 15282662
DOI: 10.1002/ajh.20119