Stockley R A, Afford S C
Clin Sci (Lond). 1984 Feb;66(2):217-24. doi: 10.1042/cs0660217.
Two-dimensional immunoelectrophoresis and conventional sodium dodecyl sulphate-polyacrylamide gel electrophoresis was performed on various mixtures of purified alpha 1-antitrypsin (alpha 1AT) and leucocyte elastase (LE). The results confirm that alpha 1AT inhibits LE by the formation of enzyme-inhibitor complexes demonstrable by both techniques. The complexes break down with time and are not affected by pH in the presence of excess alpha 1AT. However, the breakdown is more rapid in the presence of excess enzyme only at pH values where LE remains active. The resultant products of the complex breakdown include inactivated LE and alpha 1AT that has undergone limited proteolysis. It is concluded that the presence or absence of alpha 1AT-enzyme complexes as demonstrated by two-dimensional immunoelectrophoresis must be interpreted with caution when studying alpha 1AT function in lung secretions. The absence of such complexes does not mean that previous interaction with enzyme has not occurred, thereby accounting for a reduction in alpha 1AT inhibitory capacity.
对纯化的α1-抗胰蛋白酶（α1AT）和白细胞弹性蛋白酶（LE）的各种混合物进行了二维免疫电泳和传统的十二烷基硫酸钠-聚丙烯酰胺凝胶电泳。结果证实，α1AT通过形成酶-抑制剂复合物来抑制LE，这两种技术均可证明该复合物的存在。复合物会随时间分解，在存在过量α1AT的情况下不受pH值影响。然而，仅在LE仍保持活性的pH值下，存在过量酶时分解会更快。复合物分解的最终产物包括失活的LE和经历了有限蛋白水解的α1AT。得出的结论是，在研究肺分泌物中α1AT的功能时，必须谨慎解释二维免疫电泳所显示的α1AT-酶复合物的存在与否。此类复合物的不存在并不意味着先前未与酶发生相互作用，从而导致α1AT抑制能力降低。
