Puré E, Witmer M D, Lum J B, Mellman I, Unkeless J C
Laboratory of Cellular Physiology and Immunology, Rockefeller University, New York, NY 10021.
J Immunol. 1987 Dec 15;139(12):4152-8.
The murine macrophage and lymphocyte Fc receptor for aggregated IgG (Fc gamma R) has previously been characterized by using the anti-Fc gamma R monoclonal antibody (mAb), 2.4G2. In the studies presented here, we describe a new mAb, 6B7C, that defines a second epitope of the Fc gamma R. The tissue distribution of the 6B7C epitope is coincident with the 2.4G2 epitope. However, only the 2.4G2 epitope is accessible to mAb binding on intact primary macrophages or lymphocytes. The 6B7C epitope is not detectable on primary macrophages or lymphocytes but is exposed on a portion of B lymphocyte Fc gamma R after activation by lipopolysaccharide and on some tumor cell lines. The expression of the 6B7C epitope on the surface of B lymphoblasts and tumor cell lines seems to correlate with their ability to release soluble Fc gamma R. The 6B7C mAb has the advantage that it reacts with native as well as denatured receptor and therefore can be used for techniques such as immunoblotting.
此前已通过使用抗FcγR单克隆抗体（mAb）2.4G2对聚集IgG的小鼠巨噬细胞和淋巴细胞Fc受体（FcγR）进行了表征。在本文所述的研究中，我们描述了一种新的单克隆抗体6B7C，它定义了FcγR的第二个表位。6B7C表位的组织分布与2.4G2表位一致。然而，在完整的原代巨噬细胞或淋巴细胞上，只有2.4G2表位可被单克隆抗体结合。6B7C表位在原代巨噬细胞或淋巴细胞上无法检测到，但在脂多糖激活后的一部分B淋巴细胞FcγR以及一些肿瘤细胞系上会暴露出来。B淋巴母细胞和肿瘤细胞系表面6B7C表位的表达似乎与其释放可溶性FcγR的能力相关。6B7C单克隆抗体的优点在于它能与天然受体和变性受体发生反应，因此可用于免疫印迹等技术。
