利用圆二色谱和流式细胞术分析干扰素-α的构象与其抗病毒活性的相关性

Relationship between interferon-α conformation and its anti- viral activity determined by circular dichroism and flow cytometry

摘要:

利用圆二色谱 (Circular dichroism，CD) 和流式细胞术 (Flow cytometry，FCM) 分析干扰素 (Interferon，IFN)-α的构象与其抗病毒活性之间的关系。以重组人IFN-α (rIFN-α2b和rIFN-α2a) 为材料，变温CD谱分析表明，在65 ℃以下，两种IFN-α的二级结构相对稳定，当温度高于65 ℃以后，两者的二级结构发生不可逆的改变。FCM分析构象变化前后IFN-α的抗病毒活性发现，构象的改变一定程度上减弱了其抗病毒活性。rIFN-α2b和rIFN-α2a具有相似的变化趋势。以上结果表明，IFN-α的构象是影响其抗病毒活性的重要因素之一，同时也验证了CD结合FCM是分析蛋白质药物构象与其细胞水平上生物学活性相关性的较好组合。

Abstract:

The relationship between the conformation of interferon-α (IFN-α) and its anti-viral activity were analyzed by circular dichroism (CD) and flow cytometry (FCM) techniques. The recombinant human IFN-α (rIFN-α2b and rIFN-α2a) were used. CD spectra from 190 nm to 240 nm indicated that two the IFN-α showed stable secondary structure at 65 °C, but unstable when the temperature was above 65 °C, and the change was irreversible. FCM data of the anti-viral activity of IFN-α indicated that the change of its secondary structures partly weakened its anti-viral activity. The rIFN-α2b and rIFN-α2a showed the same phenomenon. These data indicated that the conformation of IFN-α is one of the factors to influence its anti-viral activity and the combination of CD and FCM is a good method to analyze the relationship between the conformation of protein drugs and their biological activities in single cell level.