A cleavable adapter to reduce nonspecific cytotoxicity of recombinant immunotoxins
A cleavable adapter to reduce nonspecific cytotoxicity of recombinant immunotoxins
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DOI：
10.1002/ijc.10809
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发表时间：
2003-01-10
影响因子：
6.4
通讯作者：
Fuchs, H
中科院分区：
文献类型：
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作者：
Heisler, I;Keller, J;Fuchs, H
与注射免疫毒素相关的问题之一是过敏反应，如血管渗漏综合征。这可以通过降低等离子体半衰期来防止。为了改善免疫毒素，减少副作用，我们以前已经描述了可切割适配器的发展。这种适配器将通常直接偶联的有毒部分和配体连接起来。在我们的研究中，我们在体外评估了皂苷直接连接或通过适配器连接表皮生长因子（EGF）的细胞毒性。免疫毒素对A-431和HER14细胞具有相似的细胞毒活性（IC50 < 10 nM）。与直接偶联的免疫毒素相比，含适配器的免疫毒素在HER 14细胞中培养6小时的上清显示出显著降低的细胞毒性。Western blotting显示，该适配器是可切割的，因此支持我们的建议，可切割的适配器可以减少非特异性的影响。在血小板少的血浆中检测到类似的半衰期缩短。相反，MCF-7细胞不受免疫毒素的影响。这是由于与A-431和HER14细胞相比，Western blotting检测到缺乏可检测的egf受体。此外，我们可以证明适配器不影响皂苷的n -糖苷酶活性。这些结果表明，使用可切割的转接器可能是免疫毒素减少因非特异性结合而杀死周围非癌细胞的有用工具。(C) 2002 Wiley-Liss, Inc。
One of the problems associated with the administration of immunotoxins is hypersensitivity reaction such as vascular leak syndrome. This may be prevented by decreasing the plasma half-life. To improve immunotoxins with respect to reduced side effects, we have previously described the development of a cleavable adapter. This adapter links the toxic moiety and ligand that are usually directly coupled. In our study, the cytotoxicity of saporin linked either directly or via the adapter to epidermal growth factor (EGF) was evaluated in vitro. The immunotoxins exhibited similar cytotoxic activity towards A-431 and HER14 cells (IC50 < 10 nM). The supernatant from 6 hr cultures of HER 14 cells incubated in the presence of the adapter-containing immunotoxin exhibited a significantly reduced cytotoxicity as compared to the directly coupled immunotoxin. Western blotting revealed that the adapter was cleaved, thus supporting our proposal that cleavable adapters may reduce nonspecific effects. A similar reduced half-life was detected in platelet-poor plasma. In contrast MCF-7 cells remain unaffected by the immunotoxins. This was shown to be due to the absence of detectable EGF-receptor in comparison to A-431 and HER14 cells as determined by Western blotting. Furthermore, we could show that the adapter does not exert an effect on the N-glycosidase activity of saporin. These results suggest that the use of cleavable adapters may be a useful tool in immunotoxins for reducing the killing of surrounding noncancerous cells due to nonspecific binding. (C) 2002 Wiley-Liss, Inc.