Hugli T E, Gerard C, Kawahara M, Scheetz M E, Barton R, Briggs S, Koppel G, Russell S
Mol Cell Biochem. 1981 Dec 4;41:59-66. doi: 10.1007/BF00225297.
Recent methodologies used in preparing anaphylatoxins from complement-activated serum are described. Activation of the alternative pathway generates C3a and C5a; however, activation of the classical pathway is required to generate the anaphylatoxin from C4. This article describes an activation scheme that simultaneously generates all three of the anaphylatoxins (e.g., C3a, C4a and C5a) in human serum and outlines a procedure for isolating each as homogeneous products. Purification of intact anaphylatoxins directly from complement-activated serum takes place only if an exopeptidase in serum, known as carboxypeptidase N (SCPN), is properly inhibited. A new series of mercapto derivatives of arginine analogs are introduced as potent and effective inhibitors of SCPN. These inhibitors permit normal complement activation but prevent degradation of the released activation fragments C3a, C4a or C5a. The SCPN inhibitor previously used was 6-aminohexanoic acid (EACA), but it required a 1 M concentration for effective inhibition, the substituted mercapto-guanido compounds prove to be effective in the mM range.
本文描述了从补体激活血清中制备过敏毒素的最新方法。替代途径的激活产生C3a和C5a；然而，经典途径的激活是从C4产生过敏毒素所必需的。本文描述了一种激活方案，该方案可在人血清中同时产生所有三种过敏毒素（例如C3a、C4a和C5a），并概述了将每种过敏毒素分离为纯品的步骤。只有当血清中的一种外肽酶，即羧肽酶N（SCPN）被适当抑制时，才能直接从补体激活血清中纯化完整的过敏毒素。引入了一系列新的精氨酸类似物的巯基衍生物，作为SCPN的有效抑制剂。这些抑制剂可使补体正常激活，但可防止释放的激活片段C3a、C4a或C5a的降解。以前使用的SCPN抑制剂是6-氨基己酸（EACA），但它需要1 M的浓度才能有效抑制，而取代的巯基胍化合物在毫摩尔范围内被证明是有效的。
