新型重组人IFN-λ2的高效表达、纯化与抗病毒活性研究

目的在大肠埃希菌中高效表达重组人干扰素λ2(rhIFNλ2),并对其抗病毒活性进行初步研究。方法根据大肠埃希菌的偏爱密码子人工设计合成人干扰素λ2(hIFNλ2)的高表达基因,将其克隆到原核表达载体pBV220,在大肠埃希菌中进行表达,表达产物经变性、复性、阳离子交换层析及分子筛层析纯化,测定其抗病毒活性、种属特异性及抗HBV活性。结果在大肠埃希菌表达的目的蛋白占细胞总蛋白量的15%左右,纯化后的纯度达到90%以上,在WISH细胞上抗VSV活性约为1.5×106IU/mg。与rhIFNα2b比较,表达产物在非灵长类细胞上的抗病毒活性较在灵长类细胞上弱,目的蛋白在HepG2.2.15细胞上表现有与rhIFNα2b相似的抗HBV活性。结论hIFNλ2可以在大肠埃希菌内实现高效表达,表达产物具有抗病毒活性,有与rhIFNα2b相似的抗HBV活性,本型IFN有较严格的种属特异性。

Expression, purification and antiviral activities of a new recombinant human interferon-λ2

OBJECTIVE: To express recombinant human interferon lambda2 in E.coli and to study its antiviral activities. METHODS: According to preferred codons used in E.coli, the highly-expressed human interferon lambda2 gene was designed, synthesized and cloned into expression vector pBV220 and transfected into E.coli DH5alpha. The expressed product was purified by using CM FF and size exclusion chromatography. Its antiviral activities were tested on different cells. RESULTS: The expressed product was calculated about 15% of the total E.coli protein. The purified protein reached about 90% purity. Its specific antiviral activity was about 1.5 x 10(6) IU/mg on WISH/VSV test system. It was shown that the antiviral activity of the product on primates-origin cells seemed to be much higher than that on other non-primates-origin cells, indicating that interferon lambda2 possessed more stringent species specificity as compared with interferon-alpha2b. New interferon lambda2 showed similar anti-HBV activity as interferon-alpha2b. CONCLUSION: Recombinant human interferon lambda2 could be expressed on E.coli. The purified product showed more stringent species specificity and similar anti-HBV activity as compared with interferon-alpha2b.