Vaughan L, Lorier M A, Carrell R W
Biochim Biophys Acta. 1982 Mar 4;701(3):339-45. doi: 10.1016/0167-4838(82)90237-0.
alpha 1-Antitrypsin has a microheterogeneity evident on isoelectric focusing as three major and several minor bands. We have identified the carbohydrate structures of the major bands; band 6 (isoform I) has three bi-antennary sidechains, band 4 (isoform II) has two bi- and one tri-antennary and band 2 (isoform III) has one bi- and two tri-antennary sidechains. The identity of the isoforms with the bands permitted their measurement in plasma by photometric scanning of the electrofocused gels. In healthy controls the levels of isoforms I, II and III were relatively constant and in the proportions of 5, 4 and 1, respectively. A marked change occurred during inflammation and oestrogen stress with isoforms II and III accounting for most of the increase in alpha 1-antitrypsin. One possible consequence of the changed proportions was shown to be the increased catabolism of the partially desialylated tri-antennary isoforms compared to that of the predominant bi-antennary form of the healthy individual.
α1 - 抗胰蛋白酶在等电聚焦时有明显的微不均一性，表现为三条主要条带和几条次要条带。我们已经确定了主要条带的碳水化合物结构；条带6（同工型I）有三个双天线侧链，条带4（同工型II）有两个双天线和一个三天线，条带2（同工型III）有一个双天线和两个三天线侧链。同工型与条带的对应关系使得通过对电聚焦凝胶进行光度扫描来测定血浆中的它们成为可能。在健康对照中，同工型I、II和III的水平相对恒定，比例分别为5:4:1。在炎症和雌激素应激期间发生了显著变化，同工型II和III占α1 - 抗胰蛋白酶增加量的大部分。比例变化的一个可能后果是，与健康个体中占主导的双天线形式相比，部分去唾液酸化的三天线同工型的分解代谢增加。
