Caspi D, Baltz M L, Feinstein A, Munn E A, Pepys M B
Clin Exp Immunol. 1984 Sep;57(3):647-56.
Clearing of turbid amyloid A fibril containing agarose gels by human serum has been ascribed to 'amyloid degrading activity'. We report here that this optical phenomenon is not due to an enzymatic reaction, does not involve proteolysis of the fibril subunits and is not inhibited by sera of patients with AA amyloidosis. The extent of clearing correlates closely with the serum albumin concentration and, as previously reported by others, serum albumin itself causes clearing comparable to that of whole serum. Furthermore addition of albumin solutions to turbid aqueous suspensions of AA amyloid fibrils causes immediate clearing. Serum albumin is known to clarify turbid non-amyloid fibril containing gels and is used commercially to improve the optical properties of radial immunodiffusion plates. We therefore propose that this property of albumin, the mechanism of which is not yet understood, underlies the so called 'amyloid degrading activity' of human serum and the latter is not therefore likely to be of in vivo biological or clinical significance.
人血清对含琼脂糖凝胶的浑浊淀粉样蛋白A纤维的清除作用被归因于“淀粉样蛋白降解活性”。我们在此报告，这种光学现象并非由酶促反应引起，不涉及纤维亚基的蛋白水解，且不受AA淀粉样变性患者血清的抑制。清除程度与血清白蛋白浓度密切相关，并且正如其他人先前报道的那样，血清白蛋白本身引起的清除效果与全血清相当。此外，向AA淀粉样纤维的浑浊水悬浮液中添加白蛋白溶液会立即产生清除效果。已知血清白蛋白可使含非淀粉样纤维的浑浊凝胶变澄清，并在商业上用于改善放射免疫扩散板的光学特性。因此，我们认为白蛋白的这种特性（其机制尚不清楚）是所谓人血清“淀粉样蛋白降解活性”的基础，因此后者可能在体内没有生物学或临床意义。
