Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou 310018, China.
Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310012, China.
Int J Mol Sci. 2024 Jun 20;25(12):6777. doi: 10.3390/ijms25126777.
Inflammatory responses and tumor developments are closely related, with interleukin-6 (IL-6) playing important roles in both processes. IL-6 has been extensively identified as a potential tumor biomarker. This study developed an isotope dilution mass spectrometry (IDMS) method for quantifying IL-6 based on signature peptides. These peptides were screened by excluding those with missed cleavage or post-translational modification. The method's accuracy was verified using amino acid-based IDMS, in which purified IL-6 protein samples were quantified after hydrolyzing them into amino acids, and no significant difference was observed (-value < 0.05). The method demonstrated good linearity and sensitivity upon testing. The specificity and matrix effect of the method were verified, and a precision study showed that the coefficient of variation was less than 5% for both the intra-day and inter-day tests. Compared to immunoassays, this method offers distinct advantages, such as the facilitation of multi-target analysis. Furthermore, the peptides used in this study are much more convenient for storage and operation than the antibodies or purified proteins typically used in immunoassays.
炎症反应与肿瘤的发生发展密切相关，白细胞介素 6（IL-6）在这两个过程中都起着重要作用。IL-6 已被广泛认为是一种潜在的肿瘤生物标志物。本研究开发了一种基于特征肽的同位素稀释质谱（IDMS）方法来定量 IL-6。通过排除那些具有缺失切割或翻译后修饰的肽来筛选这些肽。该方法的准确性通过基于氨基酸的 IDMS 进行了验证，其中将纯化的 IL-6 蛋白样品水解成氨基酸后进行定量，未观察到显著差异（- 值 < 0.05）。该方法在测试中表现出良好的线性和灵敏度。验证了该方法的特异性和基质效应，精密度研究表明，日内和日间测试的变异系数均小于 5%。与免疫测定相比，该方法具有明显的优势，例如便于多目标分析。此外，与免疫测定中通常使用的抗体或纯化蛋白相比，本研究中使用的肽在存储和操作上更加方便。
