Maeda M, Hasumura Y, Takeuchi J
Second Department of Internal Medicine, Tokyo Medical and Dental University.
Lab Invest. 1988 Jul;59(1):75-81.
Aldehyde dehydrogenase isozymes (ALDH1 or E1 and ALDH2 or E2 according to the classification by Greenfield NJ, Pietruszko R, Biochim Biophys Acta 483:35, 1977) were purified from the human liver to homogeneity by the use of ion exchange chromatography on CM-Sephadex, DEAE-Sephadex, and QAE-Sephadex and affinity chromatography on 5'-AMP Sepharose 4B, and preparative isoelectric focusing agarose electrophoresis. These were injected in rabbits to elicit antibodies against ALDH1 and ALDH2, respectively and their specificities were tested by double immunodiffusion. By gel filtration, the antibodies were separated into F'ab fragments, conjugated with horseradish peroxidase, and served to detect ALDH1 and ALDH2 proteins in normal liver tissue. Immunoelectron microscopy by the preembedding method revealed that the electron-dense materials reacted with anti-ALDH1 antibody were located in the cytoplasm of hepatocytes, mainly around the nuclear membrane, mitochondria, and endoplasmic reticulum; in the mitochondria, however, no staining was demonstrated. In contrast, the reaction with anti-ALDH2 antibody was observed only in the mitochondria. Immunostaining, performed by the enzyme-labeled antibody method demonstrated that in the hepatic lobule, there were no differences of the intensity of ALDH1 antigenicity and that of ALDH2 antigenicity between periportal (zone 1) and pericentral (zone 3) hepatocytes. These results suggest that in the human liver ALDH1 and ALDH2 are distributed equally in the periportal and centrilobular regions.
醛脱氢酶同工酶（根据Greenfield NJ、Pietruszko R在《生物化学与生物物理学学报》483:35, 1977中的分类为ALDH1或E1以及ALDH2或E2）通过在CM - 葡聚糖凝胶、二乙氨基乙基葡聚糖凝胶和季胺乙基葡聚糖凝胶上进行离子交换色谱，以及在5'-AMP琼脂糖凝胶4B上进行亲和色谱和制备性等电聚焦琼脂糖电泳，从人肝脏中纯化至同质。将这些同工酶分别注射到兔子体内以产生针对ALDH1和ALDH2的抗体，并通过双向免疫扩散测试其特异性。通过凝胶过滤，将抗体分离为F'ab片段，与辣根过氧化物酶偶联，用于检测正常肝组织中的ALDH1和ALDH2蛋白。预包埋法免疫电子显微镜显示，与抗ALDH1抗体反应的电子致密物质位于肝细胞的细胞质中，主要围绕核膜、线粒体和内质网；然而，在线粒体中未显示染色。相反，仅在线粒体中观察到与抗ALDH2抗体的反应。通过酶标抗体法进行的免疫染色表明，在肝小叶中，门周（1区）和中央周（3区）肝细胞之间的ALDH1抗原性强度和ALDH2抗原性强度没有差异。这些结果表明，在人肝脏中，ALDH1和ALDH2在门周和小叶中央区域均匀分布。
