新型人干扰素α_(1c)的纯化和活性测定

Purification and bioassay of a new type of hu- man interferon α_(1c)

目的在大肠杆菌中表达和纯化一种新型的人ＩＦＮα１ｃ。方法首先建立了表达和纯化ＩＦＮα１ｃ的实验室生产流程。根据干扰素的抗病毒、抗细胞增殖以及免疫调节特性，体外测定这种ＩＦＮ的生物学活性。结果ＥＬＩＳＡ和Ｗｅｓｔｅｒｎ免疫印迹均证实，表达产物具有干扰素的免疫反应性。ＶＳＶ－ＷＩＳＨ系统的抗病毒测活表明，表达的 ＩＦＮα１ｃ（３． ２ × １０７）的抗病毒活性较 ＩＦＮα１ｂ（１． ０ × １０７－ １． ８ × １０７）略高；而抗 Ａ５４９细胞的增殖能力则与后者相当。此外ＩＦＮα１ｃ还能增强ＮＫ细胞的杀伤活性。结论本系统成功地在大肠杆菌中表达了人ＩＦＮα１ｃ。这种高比活性的干扰素可能成为临床治疗的侯选者。

Aim To express and purify a new sub-type of interferon α, α1c in E. coli. Methods To establish a brief protocol for expression and purification of IFN-α1c. In vitro assay assay for the IFN activity is required for the measurement of antiviral, antiproliferative and immunoregulatory propeties. Results Expression of IFN-α1c was verified by its reactivity to IFN-α1c-specific neutralizing antibodies by ELISA. Western blot also detected a band with relative molecular mass(Mr) of 19 000. IFN-α1c possessed antiviral biological activity(3.2 × 107) higher than IFN-α1b (1. 0 × 107 - 1. 8 × 107) did on VSV challenged WISH cells. IFN-α1c also inhibited growth rate of A549 comparable to IFN-α1b. IFN-α1c as an immunologic effector also augmented the cytotoxic activity of NK cells. Conclusion These results demonstrate that IFN-α1c can be successfully expressed in E. coli. This interferon with high bioactivity may be a good candidate for clinical use.