Henson P M, Spiegelberg H L
J Clin Invest. 1973 May;52(5):1282-8. doi: 10.1172/JCI107296.
The ability of human myeloma proteins of different classes and subclasses and of macroglobulins (all aggregated with bis-diazotized benzidine or heat) to aggregate washed human platelets and release [(3)H]-serotonin from the platelets was investigated and compared with the activity of normal IgG and tetanus-antitetanus IgG antigen-antibody complexes. Aggregated IgG1, IgG2, IgG3, IgG4, and normal IgG complexes all aggregated platelets and caused release of serotonin to similar extents. In contrast, IgA1, IgA2, IgD, and IgE myeloma proteins as well as IgM macroglobulins were completely inactive in this respect. Approximately 50% of the actvity remained in aggregated, mildly reduced and alkylated IgG myeloma proteins and their Fc fragments, whereas aggregated F(ab')(2) fragments were completely inactive. Addition of fresh serum inhibited the release of serotonin caused by aggregated IgG1 and IgG3 proteins and normal IgG antigen-antibody complexes by about 50% but had no effect upon the release of serotonin obtained with IgG2 and IgG4 proteins. This inhibition appeared to be mediated by complement. The release of serotonin was not accompanied by liberation of the cytoplasmic enzyme lactic dehydrogenase, indicating that no significant lysis of the platelets occurred. Addition of neutrophils did not enhance the serotonin release.
研究了不同类别和亚类的人骨髓瘤蛋白以及巨球蛋白（均用双偶氮联苯胺聚集或加热聚集）聚集洗涤过的人血小板并从血小板中释放[（3）H] - 5 - 羟色胺的能力，并与正常IgG和破伤风 - 抗破伤风IgG抗原 - 抗体复合物的活性进行了比较。聚集的IgG1、IgG2、IgG3、IgG4和正常IgG复合物均能聚集血小板，并在相似程度上引起5 - 羟色胺的释放。相比之下，IgA1、IgA2、IgD和IgE骨髓瘤蛋白以及IgM巨球蛋白在这方面完全无活性。约50%的活性保留在聚集的、轻度还原和烷基化的IgG骨髓瘤蛋白及其Fc片段中，而聚集的F（ab'）2片段则完全无活性。添加新鲜血清可使聚集的IgG1和IgG3蛋白以及正常IgG抗原 - 抗体复合物引起的5 - 羟色胺释放抑制约50%，但对IgG2和IgG4蛋白所致的5 - 羟色胺释放无影响。这种抑制似乎是由补体介导的。5 - 羟色胺的释放并未伴随细胞质酶乳酸脱氢酶的释放，表明血小板未发生明显裂解。添加中性粒细胞并未增强5 - 羟色胺的释放。
