Immunochemical study of uroporphyrinogen decarboxylase in a patient with mild hepatoerythropoietic porphyria.
Immunochemical study of uroporphyrinogen decarboxylase in a patient with mild hepatoerythropoietic porphyria.
复制标题
轻度肝红细胞生成性卟啉症患者尿卟啉原脱羧酶的免疫化学研究。
DOI：
10.1172/jci112985
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Kappas,A
中科院分区：
文献类型：
--
作者：
Fujita,H;Sassa,S;Toback,AC;Kappas,A
肝红细胞生成性卟啉病(HEP)是由于血红素生物合成途径中的胞浆酶--尿卟啉原(Uro)脱羧酶的显著缺乏所致。用放射免疫法测定了一例轻度HEP患者红细胞中Uro脱羧酶蛋白的浓度，发现该酶蛋白浓度明显下降至正常对照组的7%以下。然而，这一发现与患者红细胞酶活性相反，红细胞酶活性是正常对照水平的16%，与以前报道的HEP病例不同，与其免疫活性物质相比，患者红细胞中的尿素脱羧酶活性不成比例地升高。我们的发现表明，这名患者可能存在突变的同工酶，对正常酶产生的抗体不具免疫反应。
Hepatoerythropoietic porphyria (HEP) is due to a marked deficiency of uroporphyrinogen (URO) decarboxylase, a cytosolic enzyme in the heme biosynthetic pathway. Using a radioimmunoassay method, we determined the concentration of URO decarboxylase protein in erythrocytes from a patient with mild HEP and found that the enzyme protein concentration had markedly decreased to less than 7% of the normal controls. This finding, however, was in contrast to the enzyme activity in the patient's erythrocytes, which was 16% of normal control levels and different from previously reported HEP cases in that erythrocytes in our patient contained disproportionately elevated URO decarboxylase activity in comparison to its immunoreactive material. Our findings suggests the possibility of a mutant isozyme in this patient that is not immunoreactive with an antibody raised against the normal enzyme.