A, B antigens

'A, B antigens' can also refer to...

A, B antigens

A, B antigens

Spurious hepatitis B surface antigen detection in a haemodialysis patient.

A putative, novel coli surface antigen 8B (CS8B) of enterotoxigenic Escherichia coli

Predicting Hepatitis B Virus (HBV) Surface Antigen Seroclearance in HBV e Antigen–Negative Patients With Chronic Hepatitis B: External Validation of a Scoring System

162 B-Lymphoblastic Leukemia With Aberrant T-Cell Antigen (CD5) Expression: A Rare Entity

Interference of Antibody Production to Hepatitis B Surface Antigen in a Combination Hepatitis A/Hepatitis B Vaccine

Antibody Production in Response to Hepatitis B Surface Antigen in a Combination Hepatitis A/Hepatitis B Vaccine

HBsAg/HLA‐A2 transgenic mice: a model for T cell tolerance to hepatitis B surface antigen in chronic hepatitis B virus infection

Epitope mapping of a single repetitive unit of the B13 Trypanosoma cruzi antigen as fusions to Escherichia coli LamB protein

Young Chronic Hepatitis B Patients With Nucleos(t)ide Analogue-induced Hepatitis B e Antigen Seroconversion Have a Higher Risk of HBV Reactivation

Apoptosis induced by the antigen receptor and Fas in a variant of the immature B cell line WEHI-231 and in splenic immature B cells

Death signals from the B cell antigen receptor target mitochondria, activating necrotic and apoptotic death cascades in a murine B cell line, WEHI-231

A Longitudinal Hepatitis B Vaccine Cohort Demonstrates Long-lasting Hepatitis B Virus (HBV) Cellular Immunity Despite Loss of Antibody Against HBV Surface Antigen

Construction and Characterization of a Triple-Recombinant Vaccinia Virus Encoding B7-1, Interleukin 12, and a Model Tumor Antigen

Proteasomes generate in vitro a natural peptide of influenza-A nucleoprotein functional in HLA-B27 antigen assembly

HLA-A is a Predictor of Hepatitis B e Antigen Status in HIV-Positive African Adults


Low Frequency of ErbB-2 Proto-oncogene Overexpression in Human Leukocyte Antigen-A2-Positive Breast Cancer Patients


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Mucopolysaccharides responsible for the ABO blood group system. The A and B antigens reside on the surface of erythrocytes, and differ only in the sugar attached to the penultimate monosaccharide unit of the carbohydrate chain. This minor chemical difference makes the macromolecule differentially active antigenically. The IA, IB, and i are alleles of a gene residing on the long arm of chromosome 9 between bands 34.1 and 34.2. The IA and IB alleles encode A and B glycotransferases, and the difference in their specificities is due to differences in their amino acid sequences at only four positions. These in turn result from different missense mutations in the two alleles. The A and B transferases add N-acetyl galactosamine or galactose, respectively, to the oligosaccharide terminus. The i allele encodes a defective enzyme, so no additional monosaccharide is added to the chain. Glycoproteins with properties antigenically identical to the A, B antigens are ubiquitous, having been isolated from bacteria and plants. Every human being more than 6 months old possesses those antibodies of the A, B system that are not directed against its own blood-group antigens. These “preexisting natural” antibodies probably result from immunization by the ubiquitous antigens mentioned above. The A and B antigens also occur on the surfaces of epithelial cells, and here they may mask receptors that serve as binding sites for certain pathogenic bacteria. See Chronology, 1901, Landsteiner; 1925, Bernstein; 1990, Yamomoto et al.; blood group, Helicobacter pylori, H substance, Lewis blood group, MN blood group, null allele, oligosaccharide, P blood group, Secretor gene.

Subjects: Genetics and Genomics.

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