Nettelbeck D M, Miller D W, Jérôme V, Zuzarte M, Watkins S J, Hawkins R E, Müller R, Kontermann R E
Institut für Molekularbiologie und Tumorforschung, Philipps-Universität Marburg, Emil-Mannkopff-Strabetae 2, Marburg, D-35033, Germany.
Mol Ther. 2001 Jun;3(6):882-91. doi: 10.1006/mthe.2001.0342.
The use of adenoviruses for antivascular cancer gene therapy is limited by their low transduction efficiency for endothelial cells. We have developed a recombinant bispecific antibody as a molecular bridge, linking the adenovirus capsid to the endothelial cell surface protein endoglin, for vascular targeting of adenoviruses. Endoglin (CD105), a component of the transforming growth factor beta receptor complex, represents a promising target for antivascular cancer therapy. Endoglin is expressed predominantly on endothelial cells and is upregulated in angiogenic areas of tumors. We isolated single-chain Fv fragments directed against human endoglin from a human semisynthetic antibody library. One of the isolated scFv fragments (scFv C4) bound specifically to various proliferating primary endothelial cells or cell lines including HUVEC, HDMEC, HMVEC, and HMEC. ScFv C4 was therefore used to construct a bispecific single-chain diabody directed against endoglin and the adenovirus fiber knob domain (scDb EDG-Ad). This bispecific molecule mediated enhanced and selective adenovirus transduction of HUVECs, which was independent from binding to the coxsackievirus and adenovirus receptor (CAR) and alpha(v)-integrins. Thus, adenovirus infection was redirected to a new cellular receptor (CD105) and cell entry pathway. These results demonstrate the utility of bispecific single-chain diabodies, which can be produced in large quantities in bacteria, for the retargeting of adenoviruses in cancer gene therapy.
腺病毒用于抗血管生成癌症基因治疗受到其对内皮细胞转导效率低的限制。我们开发了一种重组双特异性抗体作为分子桥，将腺病毒衣壳与内皮细胞表面蛋白内皮糖蛋白连接起来，用于腺病毒的血管靶向。内皮糖蛋白（CD105）是转化生长因子β受体复合物的一个组成部分，是抗血管生成癌症治疗的一个有前景的靶点。内皮糖蛋白主要在内皮细胞上表达，在肿瘤的血管生成区域上调。我们从人半合成抗体文库中分离出针对人内皮糖蛋白的单链Fv片段。其中一个分离出的单链Fv片段（scFv C4）能特异性结合各种增殖的原代内皮细胞或细胞系，包括人脐静脉内皮细胞（HUVEC）、人真皮微血管内皮细胞（HDMEC）、人微血管内皮细胞（HMVEC）和人乳腺上皮细胞（HMEC）。因此，scFv C4被用于构建一种针对内皮糖蛋白和腺病毒纤维结域的双特异性单链双体（scDb EDG-Ad）。这种双特异性分子介导了HUVECs中腺病毒转导的增强和选择性，这与结合柯萨奇病毒和腺病毒受体（CAR）及α(v)整合素无关。因此，腺病毒感染被重定向到一个新的细胞受体（CD105）和细胞进入途径。这些结果证明了双特异性单链双体在癌症基因治疗中用于腺病毒重靶向的实用性，其可在细菌中大量生产。
