Benditt E P, Eriksen N
Am J Pathol. 1971 Oct;65(1):231-52.
Concentrates of amyloid substance derived from organs of 10 human patients representing a variety of clinical entities were characterized according to their amino acid compositions, their electrophoretic constituents mobile in urea-starch gel at pH 3 and their stability with respect to the binding of Congo red in the pH interval 9-12.5. The analyses revealed the existence of two major classes of amyloid substance. Material from one class, embracing those cases that had a chronic inflammatory disease as the principal associated process (type A amyloidosis), had a similar amino acid composition and was distinguished by the presence in the amyloid substance of a large amount of an electrophoretically well-defined group of low-molecular-weight proteins with an unusual amino acid composition (amyloid protein A); type A amyloid substance lost the typical binding of Congo red dye at pH 11.5 or lower. Concentrates of amyloid substance in the other class (type B amyloidosis), represented by a case of multiple myeloma, 3 other cases of neoplastic disease and a case of primary cardiac amyloidosis, were distinguished by the presence of an electrophoretically more heterogeneous group of protein constituents with different mobilities and with apparently higher molecular weights than that of protein A, by an amino acid composition that is clearly different from that of the first class, and by retention of the typical Congo red-binding property at pH 12 or higher. The major constituent, protein A, of amyloid substances of the first class is clearly different from ordinary fragments of immunoglobulins in size, electrophoretic mobility, and amino acid composition.
对来自10例代表各种临床病症的人类患者器官的淀粉样物质浓缩物,根据其氨基酸组成、在pH 3的尿素 - 淀粉凝胶中可移动的电泳成分以及在pH值9 - 12.5区间内与刚果红结合的稳定性进行了表征。分析揭示了两类主要的淀粉样物质。一类物质来自那些以慢性炎症性疾病为主要相关过程的病例(A型淀粉样变性),其氨基酸组成相似,其特征是在淀粉样物质中存在大量电泳上明确界定的低分子量蛋白质组,这些蛋白质具有不寻常的氨基酸组成(淀粉样蛋白A);A型淀粉样物质在pH 11.5或更低时失去刚果红染料的典型结合。另一类(B型淀粉样变性)的淀粉样物质浓缩物,以1例多发性骨髓瘤、3例其他肿瘤性疾病病例和1例原发性心脏淀粉样变性病例为代表,其特征是存在电泳上更具异质性的蛋白质成分组,其迁移率不同且分子量明显高于蛋白A,氨基酸组成与第一类明显不同,并且在pH 12或更高时保留典型的刚果红结合特性。第一类淀粉样物质的主要成分蛋白A在大小、电泳迁移率和氨基酸组成方面明显不同于普通免疫球蛋白片段。