Vanderlaan M, Hwang M, Djanegara T
Biomedical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94550.
Environ Health Perspect. 1993 Mar;99:285-7. doi: 10.1289/ehp.9399285.
Cooking meats produces a family of heterocylic aromatic amines that are carcinogens in rodents and genotoxic in many short-term assays. Concern that these compounds may be human carcinogens has prompted us to develop immunochemical methods for quantifying these compounds in the human diet and for identifying the parent compounds and metabolites in urine and feces. Previously reported monoclonal antibodies to 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 6-phenyl-2-amino-1-methylimidazo[4,5-f]pyridine (PhIP) were used to purify by immunoaffinity these known mutagens and cross-reacting structural analogs from well-done cooked beef and urine samples. Materials recovered from the immunoaffinity columns were subsequently separated by HPLC to purify the known mutagens from cross-reacting chemicals that co-purify by immunoaffinity. Immunoaffinity chromatography was found to be a rapid means of quantifying individual known mutagens, with a minimum of precolumn sample clean-up required. In addition, this procedure has yielded several new mutagens present in cooked meats that are apparently structural analogs of PhIP. Immunoaffinity techniques were also used to purify metabolites from the urine of rats and humans exposed to MeIQx or PhIP. For MeIQx-exposed rats, the combination antibodies immunoconcentrated 75% of the total urinary radioactivity. Analysis of PhIP metabolites recovered from antibody columns is facilitated by the intrinsic fluorescence of PhIP and its metabolites, providing sufficient sensitivity to monitor individuals for the levels of PhIP excreted following consumption of typical western diets.
烹饪肉类会产生一类杂环芳香胺，这类物质对啮齿动物具有致癌性，并且在许多短期试验中具有基因毒性。鉴于这些化合物可能是人类致癌物，我们着手开发免疫化学方法，用于定量人类饮食中的这些化合物，以及鉴定尿液和粪便中的母体化合物及其代谢产物。先前报道的针对2-氨基-3,8-二甲基咪唑[4,5-f]喹喔啉（MeIQx）和6-苯基-2-氨基-1-甲基咪唑[4,5-f]吡啶（PhIP）的单克隆抗体，被用于通过免疫亲和从熟透的熟牛肉和尿液样本中纯化这些已知的诱变剂以及发生交叉反应的结构类似物。随后，通过高效液相色谱法（HPLC）对从免疫亲和柱中回收的物质进行分离，以从通过免疫亲和共同纯化的交叉反应化学物质中纯化已知的诱变剂。结果发现，免疫亲和色谱法是一种快速定量单个已知诱变剂的方法，所需的柱前样品净化步骤最少。此外，该程序还产生了几种存在于熟肉中的新诱变剂，它们显然是PhIP的结构类似物。免疫亲和技术还用于从暴露于MeIQx或PhIP的大鼠和人类尿液中纯化代谢产物。对于暴露于MeIQx的大鼠，联合抗体免疫浓缩了总尿放射性的75%。PhIP及其代谢产物的固有荧光有助于对从抗体柱中回收的PhIP代谢产物进行分析，提供了足够的灵敏度来监测个体在食用典型西方饮食后排出的PhIP水平。
