MONOCLONAL-ANTIBODY THAT IMMUNOREACTS WITH A SUBCLASS OF HUMAN RECEPTORS FOR EPIDERMAL GROWTH-FACTOR
MONOCLONAL-ANTIBODY THAT IMMUNOREACTS WITH A SUBCLASS OF HUMAN RECEPTORS FOR EPIDERMAL GROWTH-FACTOR
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DOI：
10.1247/csf.10.219
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发表时间：
1985-01-01
影响因子：
1.5
通讯作者：
SHIMIZU, N
中科院分区：
文献类型：
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作者：
BEHZADIAN, MA;SHIMIZU, N
用人表皮样癌A431细胞免疫的BALBc小鼠脾细胞与小鼠骨髓瘤P3NP细胞融合。其中一个分离的杂交瘤细胞系B4G7分泌一种IgG类单克隆抗体，抑制[125I]-EGF与A431细胞和人成纤维细胞的结合，但对小鼠3T3细胞不起作用。这种抑制是部分的（65-70%），对EGF结合数据的Scatchard分析表明，B4G7抗体优先与低亲和力的EGF受体相互作用。该单克隆抗体特异性沉淀与[125I]-EGF直接交联的A431细胞的EGF受体（Mr=170,000和155,000）。它还能从表面蛋白被125I标记的细胞、在[35S]-蛋氨酸或[32P]-正磷酸盐存在下生长的细胞以及在体外被[32P]- γ - atp磷酸化的膜组分中析出EGF受体。体内和体外受egf诱导的磷酸化的受体也被沉淀。B4G7抗体阻断。apprx。70%的EGF受体存在于人成纤维细胞中，但不刺激这些细胞的DNA合成。然而，在这种抗体存在的情况下，细胞对EGF表现出完全的有丝分裂反应，可能是通过可能是高亲和型的未阻断受体。
Spleen cells from BALBc mice immunized with human epidermoid carcinoma A431 cells were fused with mouse myeloma P3NP cells. One of the isolated hybridoma lines, B4G7, secreted a monoclonal antibody of the IgG class which inhibited the binding of [125I]-EGF to A431 cells and human fibroblasts, but not to mouse 3T3 cells. This inhibition was partial (65-70%) and Scatchard analysis of the EGF binding data suggested that the B4G7 antibody interacts preferentially with a low-affinity class of EGF receptors. This monoclonal antibody specifically precipitated EGF receptors (Mr=170,000 and 155,000) of A431 cells which were directly crosslinked with [125I]-EGF. It also precipitated EGF receptors from cells whose surface proteins were labeled with 125I, from cells grown in the presence of [35S]-methionine or [32P]-orthophosphate, and from membrane fractions phosphorylated in vitro with [32P]-.gamma.-ATP. Receptors subjected to EGF-induced phosphorylation, both in vivo and in vitro, were also precipitated. The B4G7 antibody blocked .apprx. 70% of the EGF receptors in human fibroblasts, but did not stimulate DNA synthesis in these cells. However, in the presence of this antibody, cells showed the full mitogenic response to EGF, presumably through the unblocked receptors that are likely to be of the high-affinity type.