| AAAE | amino acid activating enzyme |
|---|---|
| ACE | acetonitrile; acetylcholine esterase; acute cerebral encephalopathy; acute coronary event; adrenocor... |
| ACEDS | angiotensin-converting enzyme dysfunction syndrome |
| ACEI | angiotensin-converting enzyme inhibitor |
| AICE | angiotensin I converting enzyme |
| antibody-coated bacteria test, urinary | Fluorescent antibody technique for visualizing antibody-bacteria complexes in urine. The presence or absence of antibody-coated bacteria in urine correlates with localization of urinary tract infection in the kidney or bladder, respectively. (12 Dec 1998) |
|---|---|
| antibody combining site | <immunology> In immune network theory, an idiotope, an antigenic site of an antibody that is responsible for that antibody binding to an antigenic determinant (epitope). Also used of the site on a ligand molecule to which a cell surface receptor binds. (18 Nov 1997) |
| antibody deficiency disease | <syndrome> Any of a group of disorders associated with a defective antibody production due to defects in the B-type lymphocyte system or in T-type lymphocytes; chief manifestation is an increased susceptibility to infection by various microorganisms. See: agammaglobulinaemia, hypogammaglobulinaemia, immunodeficiency. Synonym: antibody deficiency disease. (05 Mar 2000) |
| antibody deficiency syndrome | <syndrome> Any of a group of disorders associated with a defective antibody production due to defects in the B-type lymphocyte system or in T-type lymphocytes; chief manifestation is an increased susceptibility to infection by various microorganisms. See: agammaglobulinaemia, hypogammaglobulinaemia, immunodeficiency. Synonym: antibody deficiency disease. (05 Mar 2000) |
| antibody-dependent cell cytotoxicity | The phenomenon of antibody-mediated target cell destruction by non-sensitised effector cells. The identity of the target cell varies, but it must possess surface IgG whose fc portion is intact. The effector cell is a "killer" cell possessing fc receptors. It may be a lymphocyte lacking conventional b- or T-cell markers, or a monocyte, macrophage, or polynuclear leukocyte, depending on the identity of the target cell. The reaction is complement-independent. (12 Dec 1998) |
| antibody-dependent enhancement | Enhancement of viral infectivity caused by non-neutralizing antibodies. There are at least two mechanisms known to account for this: mediation by fc receptors (receptors, fc) or by complement receptors (receptors, complement). Either the virus is complexed with antiviral IgG and binds to fc receptors, or virus is coated with antiviral IgM and binds to complement receptors. (12 Dec 1998) |
| antibody diversity | The phenomenon of immense variability characteristic of antibodies, which enables the immune system to react specifically against the essentially unlimited kinds of antigens it encounters. Antibody diversity is accounted for by three main theories: 1) the germ line theory, which holds that each antibody-producing cell has genes coding for all possible antibody specificities, but expresses only the one stimulated by antigen; 2) the somatic mutation theory, which holds that antibody-producing cells contain only a few genes, which produce antibody diversity by mutation; and 3) the gene rearrangement theory, which holds that antibody diversity is generated by the rearrangement of variable region gene segments during the differentiation of the antibody-producing cells. (12 Dec 1998) |
| antibody excess | In a precipitation test, the presence of antibody in an amount greater than that required to combine with all of the antigen present. (05 Mar 2000) |
| antibody-forming cell | <immunology> B-cells (plasma cells) that are dedicated to producing secreted antibodies. (09 Feb 1998) |
| antibody induced lysis | <haematology> The term is imprecise and should not be used since there is confusion as to which mechanism is involved, i.e. Natural killing or complement lysis. See: complement lysis, natural killer cells. (09 Feb 1998) |
| antibody producing cell | <immunology> A lymphocyte of the B series synthesising and releasing immunoglobulin. Equivalent to plasmacyte and plasma cell. (18 Nov 1997) |
| antibody-producing cells | Cells of the lymphoid series that can react with antigen to produce specific cell products called antibodies. Various cell subpopulations, often B-lymphocytes, can be defined, based on the different classes of immunoglobulins that they synthesise. (12 Dec 1998) |
| antibody specificity | The property of antibodies which enables them to react with some antigenic determinants and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site. (12 Dec 1998) |
| antibody technology | <molecular biology> Techniques for the synthesis of polyclonal and monoclonal antibodies for use in research, diagnostics and therapeutics. (09 Feb 1998) |
| antigen-antibody complex | The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes immune complex diseases. If the antigen is polyvalent the complex may be insoluble. Immune complexes activate complement through the classical pathway. See: glomerulonephritis, Arthus reaction, type III hypersensitivity. (12 Dec 1998) |