Isolation and characterization of the Fc receptor from the fetal yolk sac of the rat.
Isolation and characterization of the Fc receptor from the fetal yolk sac of the rat.
复制标题
从大鼠的胎儿蛋黄囊中分离和表征FC受体。
DOI：
10.1083/jcb.111.5.1867
复制
发表时间：
1990-11
影响因子：
7.8
通讯作者：
Rodewald, R
中科院分区：
文献类型：
--
作者：
Roberts, D M;Guenthert, M;Rodewald, R
胎鼠卵黄囊和新生大鼠近端小肠选择性转运母体IgG。IgG-Fc受体被认为介导跨两种组织上皮的转运。我们使用小鼠单克隆抗体（MC-39）针对新生儿肠道Fc受体的45-54-kD组分，以寻找可能在胎儿卵黄囊中起Fc受体作用的抗原相关蛋白。在卵黄囊免疫印迹中，MC-39识别表观分子量为54-58 kD的蛋白条带。免疫荧光显示MC-39与卵黄囊内胚层结合。在免疫金标记实验中，MC-39主要与内胚层细胞的顶端细胞质和基底外侧膜附近区域的小泡有关。MC- 39交叉反应蛋白和β 2-微球蛋白，肠道Fc受体的一个组成部分，从洗涤剂溶解的卵黄囊通过亲和纯化共纯化，选择的蛋白质，如肠道受体，结合到IgG在pH 6.0和pH 8.0洗脱。总之，这些数据表明，我们已经分离出的Fc受体的卵黄囊，这种受体的结构和功能相关的新生儿肠道的Fc受体。一个意想不到的发现是，不像肠道受体结合母体IgG的顶端细胞表面，卵黄囊受体似乎结合IgG只在顶端的舱室，我们建议代表内体复合物。
The yolk sac of the fetal rat and the proximal small intestine of the neonatal rat selectively transport maternal IgG. IgG-Fc receptors are thought to mediate transport across the epithelium of both tissues. We used a mouse mAb (MC-39) against the 45-54-kD component of the Fc receptor of the neonatal intestine to find an antigenically related protein that might function as an Fc receptor in fetal yolk sac. In immunoblots of yolk sac, MC-39 recognized a protein band with apparent molecular mass of 54-58 kD. MC-39 bound to the endoderm of yolk sac in immunofluorescence studies. In immunogold-labeling experiments MC-39 was associated mainly with small vesicles in the apical cytoplasm and in the region near the basolateral membrane of endodermal cells. The MC- 39 cross-reactive protein and beta 2-microglobulin, a component of the intestinal Fc receptor, were copurified from detergent-solubilized yolk sac by an affinity purification that selected for proteins which, like the intestinal receptor, bound to IgG at pH 6.0 and eluted at pH 8.0. In summary, the data suggest that we have isolated the Fc receptor of the yolk sac and that this receptor is structurally and functionally related to the Fc receptor of the neonatal intestine. An unexpected finding is that, unlike the intestinal receptor which binds maternal IgG on the apical cell surface, the yolk sac receptor appears to bind IgG only within apical compartments which we suggest represent the endosomal complex.