Lawrence D A, Weigle W O, Spiegelberg H L
J Clin Invest. 1975 Feb;55(2):368-76. doi: 10.1172/JCI107940.
The cytophilic activity of human myeloma proteins of different classes and subclasses for lymphocytes, monocytes, and neutrophils was investigated. Binding of both unaggregated immunoglobulins (Ig) and Ig aggregated with rabbit F(ab)2 anti-Fab fragment sera was determined. Lymphocytes bound unaggregated IgG1 and IgG3 proteins, but none of the proteins of the other classes. In contrast, after aggregation, IgG of all subclasses and IgE proteins bound to lymphocytes; aggregated proteins of the other classes did not bind. Monocytes bound unaggregated IgG1 and Ig3 better than Ig4 whereas the binding of proteins of other classes was insignificant. Neutrophils bound unaggregated IgG1 and IgG3 proteins and, in addition, IgA1, IgA2, secretory IgA, and IgG4 proteins. After aggregation, the neutrophils bound more Ig of all classes; however, the differences between the amounts bound remained similar to the amounts of unaggregated proteins. The native structure of the Ig molecule is necessary for the maintenance of complete activity, because Fc fragments bound less than intact Ig, and reduction and alkylation abolished cytophilia. The Fc receptors on all cell types tested showed no specificity for any of the respective cytophilic IgG subclasses; however, neutrophils appear to have separate receptors for IgG and IgA proteins.
研究了不同类别和亚类的人骨髓瘤蛋白对淋巴细胞、单核细胞和中性粒细胞的亲细胞活性。测定了未聚集的免疫球蛋白（Ig）以及与兔F（ab）2抗Fab片段血清聚集的Ig的结合情况。淋巴细胞能结合未聚集的IgG1和IgG3蛋白，但不结合其他类别的蛋白。相反，聚集后，所有亚类的IgG和IgE蛋白都能与淋巴细胞结合；其他类别的聚集蛋白则不结合。单核细胞对未聚集的IgG1和Ig3的结合优于Ig4，而其他类别的蛋白结合不明显。中性粒细胞能结合未聚集的IgG1和IgG3蛋白，此外还能结合IgA1、IgA2、分泌型IgA和IgG4蛋白。聚集后，中性粒细胞能结合更多所有类别的Ig；然而，结合量之间的差异与未聚集蛋白的量相似。Ig分子的天然结构对于维持完全活性是必要的，因为Fc片段的结合少于完整的Ig，并且还原和烷基化会消除亲细胞性。所有测试细胞类型上的Fc受体对任何相应的亲细胞性IgG亚类均无特异性；然而，中性粒细胞似乎对IgG和IgA蛋白有单独的受体。
