CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049, China.
ACS Nano. 2015 Nov 24;9(11):10979-90. doi: 10.1021/acsnano.5b04261. Epub 2015 Oct 9.
Precisely quantifying the membrane protein expression level on cell surfaces is of vital importance for early cancer diagnosis and efficient treatment. We demonstrate that gold nanoparticle bioconjugated by a rationally designed peptide as nanoprobe possesses selective labeling and accurate quantification capacity of integrin GPIIb/IIIa on the human erythroleukemia cell line. Through selective recognition and marking of integrin, two-photon photoluminescence of the nanoprobe is exploited for direct observation of protein spatial distribution on cell membrane. More importantly, utilizing intrinsic enzyme-like catalysis property of the nanoprobe, the expression level of integrin on human erythroleukemia cells can be quantitatively counted in an amplified and reliable colorimetric assay without cell lysis and protein extraction process. In addition, the analysis of the correlation between the gold nanoparticle and the membrane protein via relevant inductively coupled plasma mass spectrometry measurement verifies the reliability of the new analytical method. It is anticipated that this facile and efficient strategy holds a great promise for a rapid, precise, and reliable quantification of interested functional membrane proteins on the cell surface.
精确量化细胞表面的膜蛋白表达水平对于癌症的早期诊断和有效治疗至关重要。我们证明，通过合理设计的肽作为纳米探针进行金纳米粒子生物缀合，具有整合素 GPIIb/IIIa 在人红白血病细胞系上的选择性标记和准确定量能力。通过对整合素的选择性识别和标记，利用纳米探针的双光子光致发光，可以直接观察细胞膜上蛋白质的空间分布。更重要的是，利用纳米探针固有的酶样催化特性，在不进行细胞裂解和蛋白质提取的情况下，通过放大和可靠的比色测定法，可定量计数人红白血病细胞上整合素的表达水平。此外，通过相关电感耦合等离子体质谱测量对金纳米粒子与膜蛋白之间的相关性进行分析，验证了新分析方法的可靠性。预计这种简便高效的策略将为快速、精确、可靠地定量感兴趣的功能性膜蛋白在细胞表面的表达提供巨大的可能性。
