Receptors for IgA on human lymphocytes--I. detection and specificity.
Receptors for IgA on human lymphocytes--I. detection and specificity.
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人淋巴细胞上的 IgA 受体——I．
DOI：
10.1016/0161-5890(81)90085-7
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发表时间：
1981
影响因子：
3.6
通讯作者：
Lydyard,PM
中科院分区：
文献类型：
--
作者：
Fanger,MW;Lydyard,PM
本研究用高致敏牛红细胞(EA-α)玫瑰花环技术检测了大量携带特异性Ig A受体的外周血淋巴细胞(RFC-α)。虽然分离后即刻即可检测到较高比例的α细胞(30%)，但更高比例的淋巴细胞(65%)在隔夜孵育后表达α。检测RFCIgA依赖于α抗体对指示细胞的致敏程度。携带Ig A、Ig G或Ig M受体的细胞百分比表明，某些携带Ig A受体的淋巴细胞(T细胞)还携带另一Ig亚型的Fc受体。用骨髓瘤免疫球蛋白进行的花环抑制研究表明，rfcα对免疫球蛋白A_2比免疫球蛋白A_1亚类有更强的特异性。该单体以与二聚体大致相同的单位毫克效率阻断Ig A玫瑰花环的形成，这提供了无论是分泌成分还是多价Fc展示对与rFCα相互作用都不是关键的证据。此外，缺失Cα3结构域的骨髓瘤免疫球蛋白A抑制免疫球蛋白A花环形成的能力表明，与α相互作用的位置位于Cα2结构域，不依赖于H链配对。这些发现似乎与rfcα及其相关细胞在分泌性免疫防御中的主要作用一致。
In this study large numbers of peripheral blood lymphocytes bearing receptors specific for IgA (RFcα) were detected by a rosetting technique using highly sensitized ox erythrocytes (EAα). Although significant percentages of RFcα bearing cells could be detected immediately after isolation (30%), even greater percentages of lymphocytes (65%) expressed RFcα after overnight incubation. Detection of RFcα was dependent on the degree of sensitization of the indicator cells by IgA antibody. The percentages of cells bearing receptors for IgA, IgG or IgM, indicated that some lymphocytes (T cells) bearing receptors for IgA also bear Fc receptors for another Ig isotype. Rosette inhibition studies using myeloma immunoglobulins suggested that RFcα have a greater specificity for the IgA2 than for the IgA1 subclass. That monomer blocked IgA rosette formation with approximately the same efficiency per mg as the dimer provided evidence that neither secretory component nor multivalent Fc display were critical to interaction with RFcα. Furthermore, the ability of a myeloma IgA with a missing Cα3 domain to inhibit IgA rosette formation indicated that the site on IgA which interacts with RFcα is in the Cα2 domain and is not dependent on H chain pairing. These findings seem consistent with a major role in secretory immune defense for RFcα and the cells with which they are associated.