Department of Biochemistry and Molecular Biology, Faculty of Chemical Sciences, Complutense University, 28040 Madrid, Spain.
University Institute of Biomedical and Health Research (IUIBS), Las Palmas University, 35016 Las Palmas de Gran Canaria, Spain.
Biomolecules. 2023 Jun 26;13(7):1042. doi: 10.3390/biom13071042.
Immunotoxins (ITXs) are chimeric molecules that combine the specificity of a targeting domain, usually derived from an antibody, and the cytotoxic potency of a toxin, leading to the selective death of tumor cells. However, several issues must be addressed and optimized in order to use ITXs as therapeutic tools, such as the selection of a suitable tumor-associated antigen (TAA), high tumor penetration and retention, low kidney elimination, or low immunogenicity of foreign proteins. To this end, we produced and characterized several ITX designs, using a nanobody against EGFR (V 7D12) as the targeting domain. First, we generated a nanoITX, combining V 7D12 and the fungal ribotoxin α-sarcin (αS) as the toxic moiety (VEGFRαS). Then, we incorporated a trimerization domain (TIE) into the construct, obtaining a trimeric nanoITX (TriVEGFRαS). Finally, we designed and characterized a bispecific ITX, combining the V 7D12 and the scFv against GPA33 as targeting domains, and a deimmunized (DI) variant of α-sarcin (BsITXαSDI). The results confirm the therapeutic potential of α-sarcin-based nanoITXs. The incorporation of nanobodies as target domains improves their therapeutic use due to their lower molecular size and binding features. The enhanced avidity and toxic load in the trimeric nanoITX and the combination of two different target domains in the bispecific nanoITX allow for increased antitumor effectiveness.
免疫毒素（ITX）是一种嵌合分子，它将靶向结构域的特异性（通常来自抗体）与毒素的细胞毒性效力结合起来，导致肿瘤细胞的选择性死亡。然而，为了将 ITX 用作治疗工具，必须解决和优化几个问题，例如选择合适的肿瘤相关抗原（TAA）、高肿瘤穿透和保留、低肾脏消除或外来蛋白的低免疫原性。为此，我们使用针对 EGFR 的纳米体（V 7D12）作为靶向结构域，生成并表征了几种 ITX 设计。首先，我们生成了一种纳米 ITX，将 V 7D12 和真菌核糖体毒素 α-菌毒素（αS）组合作为毒性部分（VEGFRαS）。然后，我们将三聚体化结构域（TIE）引入构建体中，得到三聚体纳米 ITX（TriVEGFRαS）。最后，我们设计并表征了一种双特异性 ITX，将 V 7D12 和针对 GPA33 的 scFv 作为靶向结构域，以及 α-菌毒素的去免疫化（DI）变体（BsITXαSDI）。结果证实了基于 α-菌毒素的纳米 ITX 的治疗潜力。将纳米体作为靶向结构域结合，由于其分子尺寸较小和结合特征，改善了它们的治疗用途。三聚体纳米 ITX 中的增强亲和力和毒性负荷以及双特异性纳米 ITX 中两种不同靶向结构域的组合，允许增加抗肿瘤效果。
Zotero 插件
