Shanehbandi Dariush, Majidi Jafar, Kazemi Tohid, Baradaran Behzad, Aghebati-Maleki Leili, Fathi Farzaneh, Ezzati Nazhad Dolatabadi Jafar
Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
Adv Pharm Bull. 2017 Jun;7(2):189-194. doi: 10.15171/apb.2017.023. Epub 2017 Jun 30.
Surface plasmon resonance (SPR) sensing confers a real-time assessment of molecular interactions between biomolecules and their ligands. This approach is highly sensitive and reproducible and could be employed to confirm the successful binding of drugs to cell surface targets. The specific affinity of monoclonal antibodies (MAb) for their target antigens is being utilized for development of immuno-sensors and therapeutic agents. CD20 is a surface protein of B lymphocytes which has been widely employed for immuno-targeting of B-cell related disorders. In the present study, binding ability of an anti-CD20 MAb to surface antigens of intact target cells was investigated by SPR technique. Two distinct strategies were used for immobilization of the anti-CD20 MAb onto gold (Au) chips. MUA (11-mercaptoundecanoic acid) and Staphylococcus aureus protein A (SpA) were the two systems used for this purpose. A suspension of CD20-positive Raji cells was injected in the analyte phase and the resulting interactions were analyzed and compared to those of MOLT-4 cell line as CD20-negative control. Efficient binding of anti-CD20 MAb to the surface antigens of Raji cell line was confirmed by both immobilizing methods, whereas this MAb had not a noticeable affinity to the MOLT-4 cells. According to the outcomes, the investigated MAb had acceptable affinity and specificity to the target antigens on the cell surface and could be utilized for immuno-detection of CD20-positive intact cells by SPR method.
表面等离子体共振（SPR）传感可实时评估生物分子与其配体之间的分子相互作用。这种方法高度灵敏且可重复，可用于确认药物与细胞表面靶点的成功结合。单克隆抗体（MAb）对其靶抗原的特异性亲和力正被用于免疫传感器和治疗剂的开发。CD20是B淋巴细胞的一种表面蛋白，已被广泛用于B细胞相关疾病的免疫靶向治疗。在本研究中，通过SPR技术研究了抗CD20单克隆抗体与完整靶细胞表面抗原的结合能力。采用了两种不同的策略将抗CD20单克隆抗体固定在金（Au）芯片上。MUA（11-巯基十一烷酸）和金黄色葡萄球菌蛋白A（SpA）是用于此目的的两个系统。将CD20阳性的Raji细胞悬液注入分析物相中，并对产生的相互作用进行分析，并与作为CD20阴性对照的MOLT-4细胞系的相互作用进行比较。两种固定方法均证实抗CD20单克隆抗体与Raji细胞系表面抗原有效结合，而该单克隆抗体对MOLT-4细胞没有明显亲和力。根据结果，所研究的单克隆抗体对细胞表面的靶抗原有可接受的亲和力和特异性，可用于通过SPR方法免疫检测CD20阳性完整细胞。
