Cellular and Molecular Medicine Department, Centro de Investigaciones Biológicas, Madrid, Spain.
J Biomater Appl. 2012 May;26(8):1069-89. doi: 10.1177/0885328210393294. Epub 2011 May 17.
Aiming to characterize the use of biomaterials in cancer therapy, we took advantage of the n-type semiconductor properties, which upon irradiation excite their electrons into the conduction band to induce photoelectrochemical reactions generating oxygen reactive species (ROS). Indeed, photoactivated TiO(2) nanoparticles have been shown to kill in vitro either bacteria or tumor cells in culture following UV irradiation, as a consequence of the ROS levels generated; the killing was highly effective although devoid of specificity. In this report, we have directed the TiO(2) nanoparticles to particular targets by coupling them to the monoclonal antibody (mAb) Nilo1, recognizing a surface antigen in neural stem cells within a cell culture, to explore the possibility of making this process specific. TiO(2) nanoparticles generated with particular rutile/anatase ratios were coupled to Nilo1 antibody and the complexes formed were highly stable. The coupled antibody retained the ability to identify neural stem cells and upon UV irradiation, the TiO(2) nanoparticles were activated, inducing the selective photokilling of the antibody-targeted cells. Thus, these data indicate that antibody-TiO(2) complexes could be used to specifically remove target cell subpopulations, as demonstrated with neural stem cells. The possible applications in cancer therapy are discussed.
为了研究生物材料在癌症治疗中的应用，我们利用了 n 型半导体的特性，当受到照射时，其电子会被激发到导带中，从而引发光电化学反应，产生氧活性物质 (ROS)。事实上，已证明光激活的 TiO2 纳米粒子在紫外线照射下可以杀死体外的细菌或肿瘤细胞，这是由于产生了 ROS 水平；尽管没有特异性，但这种杀伤效果非常高。在本报告中，我们通过将 TiO2 纳米粒子与单克隆抗体 (mAb) Nilo1 偶联，使其靶向特定目标，Nilo1 抗体识别细胞培养物中的神经干细胞表面抗原，以探索使这一过程具有特异性的可能性。用特定的锐钛矿/金红石比例生成的 TiO2 纳米粒子与 Nilo1 抗体偶联，所形成的复合物非常稳定。偶联的抗体保留了识别神经干细胞的能力，并且在紫外线照射下，TiO2 纳米粒子被激活，诱导抗体靶向细胞的选择性光杀伤。因此，这些数据表明，抗体-TiO2 复合物可用于特异性去除靶细胞亚群，如神经干细胞。文中还讨论了其在癌症治疗中的可能应用。
