Antibody is a three-lobed globulin containing two short and two long chains of protein, found in the blood and other body fluids, that can be incited by the presence of antigen; it has a destructive influence on the antigen that stimulated its formation, thus producing immunity; the structure has considerable flexibility and is hinged, so that it can pivot from a taut T-shape to a forked Y-shape.
anticardiolipin a. Antibody that reacts with cardiolipin; may be elevated in patients with systemic lupus erythematosus.
Associated with increased incidence of thrombosis, fetal loss, and other abnormalities.
α 1 antichymotripsin A protein that inhibits the action of the digestive enzyme
antinuclear a. An antibody that acts against components of cell nuclei; found in systemic lupus erythematosus and certain collagen diseases.
antiphospholipid a.’s A group of antibodies acting against phosphorylated polysaccharide esters of fatty acids, thought to be markers of a hypercoagulable state of the blood.
antisperm a.’s Antibodies that immobilize spermatozoa or interfere in any way with spermatozoan activity. They are found in the serum of both males and females and act locally; level of their activity fluctuates.
blocking a. Antibody that, by combining with antigen, stops further activity of that antigen.
complement-fixing a., CF a. Antibody that, when combined with antigen, activates complement.
monoclonal a.’s Antibodies that are chemically and immunologically homogeneous, artificially produced in the laboratory to react with specific antigens; used as probes in cell biology and biochemistry and, experimentally, to treat certain forms of cancer.
natural a.’s Antibodies occurring naturally in the body without apparent antigenic
stimulation from infection or immunization.
neutralizing a. Antibody that, by binding to an infective agent, limits its infectivity.