Vanderlaan M, Alexander J, Thomas C, Djanegara T, Hwang M, Watkins B E, Wallin H
Biomedical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94550.
Carcinogenesis. 1991 Feb;12(2):349-54. doi: 10.1093/carcin/12.2.349.
Monoclonal antibodies, previously selected to bind either 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) or 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) were evaluated to determine their binding properties with several known metabolites of these compounds purified from rat hepatocyte cultures. Both 2-N- and 5-substituted MeIQx metabolites were recognized by antibodies AIA-2 and AIA-11, while antibodies AIA-1 and AIA-12 bound N-substituted metabolites only. Anti-PhIP antibodies bound N-hydroxy-PhIP, N-sulfinamide-glutathione-PhIP and N-hydroxy-glucuronide-PhIP. Immunoaffinity columns incorporating these antibodies were used to concentrate and purify both the unmetabolized parent compounds and several relatively non-polar metabolites from the urine of rats exposed either to MeIQx or PhIP. Several of these metabolites corresponded with available standards of previously identified polar conjugate metabolites, e.g. N-sulfamate-MeIQx and N(OH)-gluc-PhIP, while others are as yet unidentified. Immunoaffinity chromatography is demonstrated as a promising means of selectively concentrating metabolites of PhIP and MeIQx from urine.
对先前筛选出的分别能与2-氨基-3,8-二甲基咪唑并[4,5-f]喹喔啉（MeIQx）或2-氨基-1-甲基-6-苯基咪唑并[4,5-b]吡啶（PhIP）结合的单克隆抗体进行了评估，以确定它们与从大鼠肝细胞培养物中纯化得到的这两种化合物的几种已知代谢物的结合特性。2-N-取代和5-取代的MeIQx代谢物均能被抗体AIA-2和AIA-11识别，而抗体AIA-1和AIA-12仅能结合N-取代的代谢物。抗PhIP抗体能结合N-羟基-PhIP、N-亚磺酰胺-谷胱甘肽-PhIP和N-羟基-葡糖醛酸-PhIP。使用结合了这些抗体的免疫亲和柱，从暴露于MeIQx或PhIP的大鼠尿液中浓缩和纯化未代谢母体化合物以及几种相对非极性的代谢物。其中几种代谢物与先前鉴定的极性共轭代谢物的现有标准品相对应，例如N-氨基磺酸酯-MeIQx和N(OH)-葡糖-PhIP，而其他一些代谢物尚未鉴定。免疫亲和色谱法被证明是一种从尿液中选择性浓缩PhIP和MeIQx代谢物的有前景的方法。
