ABC transporters
ATP-binding cassette transporters are a family of transmembrane proteins that function in the transort of a wide variety of substrates across extra- and intracellular membranes, including metabolic products, lipids and sterols, and drugs. ABC transporters are involved in tumor resistance, cystic fibrosis, bacterial multidrug resistance and a range of other inherited human diseases.
ADME
ADME is a common acronym for absorption, distribution, metabolism and excretion. ADME studies are among a series of non-clinical safety studies conducted prior to human clinical trials. These studies are part of the evaluation to characterize a drug candidate under the conditions of the supported clinical trial.
AhR
Aryl hydrocarbon receptor. AhRs mediate the induction of CYP1A enzymes by agents such as
b-naphthoflavone, 3-methylcholanthrene, Aroclor 1254 and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).
aliquot
A portion obtained by dividing the whole into several parts, especially one of two or more samples of a substance that have the same volume or weight.
allelozyme
An allelic (genetic) variant of an enzyme. The term was first used to describe variants of alcohol dehydrogenase, but may be applied to other enzymes.
antibody
A protein produced by B lymphocytes in response to, and interacting specifically with, an antigen. This antigen-antibody reaction forms the basis of immunity, and is exploited in various immunoassays. (Also see
IgG.)
antigen
A substance, usually a protein, that is recognized by the immune system as foreign and that can elicit an immune response, resulting in production of an antibody.
assay
The analysis of a substance or mixture to determine its constituents and the relative proportions of each. This term is synonymous with “test”.