title: Electrochemical immunoassay on expression of integrin β1 on tumor cells and drug-resistant tumor cells.
abstract: An electrochemical indirect competitive immunoassay protocol as a promising cytosensing strategy was developed to detect integrin β1 expression on human breast cancer MCF-7 cells and adriamycin-resistant human breast cancer MCF-7 (MCF-7/ADR) cells and quantify the cell number. Integrin α5β1 was adsorbed on the gold-nanoparticle modified glassy carbon electrode to bind integrin β1 monoclonal antibody (anti-CD29 mAb). A sandwich structure was then formed using nanocomposites which consisted of horseradish peroxidase (HRP) labeled anti-antibody and gold nanoparticles. HRP bound on the electrode surface could cause an amperometric response of the hydroquinone-H(2)O(2) system. The assembly of the sandwich structure was inhibited by tumor cells to give decreased enzyme-catalytic signals due to the capture of anti-CD29 mAb by integrin β1 on cell membranes. Under optimal conditions the relative current change (S) was proportional to the cell concentration from 1.6 × 10(3) to 2.0 × 10(6) cells mL(-1) with a detection limit of 700 cells mL(-1). Integrin β1 expression in MCF-7/ADR cells was found to be significantly higher than that in MCF-7 cells, indicating the increased adhesion ability of MCF-7/ADR cells.
authors: Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China.
authors: Bei
authors: B
authors: Zhou
authors: Xiuli
authors: X
authors: Xiao
authors: Lili
authors: L
authors: Xu
authors: Lian
authors: L
authors: Zhu
authors: Liang
authors: L
authors: Tan
authors: Hao
authors: H
authors: Tang
authors: Youyu
authors: Y
authors: Zhang
authors: Qingji
authors: Q
authors: Xie
authors: Shouzhuo
authors: S
authors: Yao
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D000911:Antibodies, Monoclonal / Q000276:immunology; D001940:Breast / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D001943:Breast Neoplasms / Q000188:drug therapy / Q000276:immunology*; D004317:Doxorubicin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D055664:Electrochemical Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D019012:Integrin beta1 / Q000032:analysis* / Q000276:immunology; D057230:Limit of Detection; D061986:MCF-7 Cells; D051379:Mice
chemical_list: D000903:Antibiotics, Antineoplastic; D000911:Antibodies, Monoclonal; D019012:Integrin beta1; D004317:Doxorubicin