Shimada T, Yoshida H, Tokumoto H, Yodoi J, Sugiyama T
Department of Pathology, Faculty of Medicine, Kyoto University, Japan.
J Immunol Methods. 1991 Feb 15;136(2):159-67. doi: 10.1016/0022-1759(91)90002-w.
To establish a sensitive method to detect IgA Fc receptors (Fc alpha R) on human and murine lymphoid cells, fluorescent microspheres (FMS) were used in a flow cytometric assay. The following three assays with FMS were tested and compared with a conventional indirect Fc alpha R assay using FITC-labeled anti-IgA: (1) direct cell binding assay with murine myeloma IgA(MOPC315)-coated FMS(IgA-FMS assay), (2) indirect assay with TNP-BSA-coated FMS which bind to cells preincubated with MOPC315 IgA bearing anti-TNP activity (TNP-BSA-FMS assay), and (3) indirect assay with anti-IgA coated FMS after preincubation of the cells with IgA(anti-IgA-FMS assay). In these three assays for Fc alpha R using FMS, the binding of IgA to the cells was not affected by purified IgM or IgG preparations. In both indirect assays using TNP-BSA-FMS and anti-IgA-FMS, sharp and dose dependent IgA binding was obtained at lower IgA concentrations ranging from 4 to 125 micrograms/ml as compared with the conventional indirect assay. The background MFI levels in all these FMS assays remained as low as those in the conventional assay. These findings suggest that FMS coupled with TNP-BSA or anti-IgA antibodies is suitable for the detection of Fc alpha R on both murine and human T cells.
为建立一种检测人和鼠淋巴细胞上IgA Fc受体（FcαR）的灵敏方法，在流式细胞术检测中使用了荧光微球（FMS）。对以下三种使用FMS的检测方法进行了测试，并与使用异硫氰酸荧光素（FITC）标记的抗IgA的传统间接FcαR检测方法进行了比较：（1）用鼠骨髓瘤IgA（MOPC315）包被的FMS进行直接细胞结合检测（IgA-FMS检测），（2）用与预先用具有抗TNP活性的MOPC315 IgA孵育的细胞结合的三硝基苯磺酸-牛血清白蛋白（TNP-BSA）包被的FMS进行间接检测（TNP-BSA-FMS检测），以及（3）细胞先用IgA预孵育后，用抗IgA包被的FMS进行间接检测（抗IgA-FMS检测）。在这三种使用FMS检测FcαR的方法中，IgA与细胞的结合不受纯化的IgM或IgG制剂的影响。与传统间接检测相比，在使用TNP-BSA-FMS和抗IgA-FMS的两种间接检测中，在4至125微克/毫升的较低IgA浓度下均获得了明显的、剂量依赖性的IgA结合。所有这些FMS检测中的背景平均荧光强度（MFI）水平与传统检测中的一样低。这些发现表明，与TNP-BSA或抗IgA抗体偶联的FMS适用于检测鼠和人T细胞上的FcαR。
