【作者】 张徐凯；

【导师】 李建蓉； 黄汉菊；

【作者基本信息】 华中科技大学 ， 病原生物学， 2007， 硕士

【摘要】 目的:为了改善干扰素(IFN)的稳定性和生物学活性,采用高分子设计原理,以活化的聚乙二醇(PEG)来修饰干扰素,以几种不同的PEG修饰剂对干扰素分别进行修饰,比较不同PEG及不同修饰率修饰干扰素与未修饰干扰素在热稳定性、酶稳定性、耐酸碱性方面的差异,并对产物进行抗病毒性能与抑制肿瘤细胞增殖性能的检测。方法:以顺丁烯二酸酐(MAn)和烯丙基化合物为单体,经自由基共聚制备了大分子量的PEG为长侧链的聚合物来修饰干扰素。采用SDS-PAGE电泳法测定PEG修饰干扰素的分子量,以证实合成产物是否与理论设计相符;通过考察热稳定性、酶稳定性、耐酸碱性来比较PEG修饰干扰素与未修饰干扰素之间性能的差异;用Hep-2细胞-VSV病毒体系检测合成产物抗病毒性能;采用MTT法测定合成产物对肿瘤细胞增殖的影响。结果:以不同的修饰剂和不同的修饰率制备了九种PEG修饰IFN;DS-PAGE电泳结果表明有聚合物-IFN结合物生成,分子量为6万(以修饰剂APEO90—4万修饰)的产物三种、分子量为4万(以修饰剂APEO90—2万与APEO60—2万修饰)的产物六种; PEG修饰干扰素的热稳定性、酶稳定性、耐酸碱性比未修饰干扰素均有明显的增加;MTT法实验表明PEG修饰的IFN对肿瘤细胞生长抑制作用比未修饰IFN增强,9种PEG修饰IFN(产物编号1-9)分别提高了56.3%、35.2%、17.8%、42.3%、23.5%、14.6%、45.5%、26.5%、11.4%,而其抗病毒性能则有不同程度的下降,依次下降了52%、78%、88%、48%、78%、89%、54%、79%、88%。结论:PEG修饰干扰素的热稳定性、酶稳定性、耐酸碱性均有显著的提高;PEG修饰干扰素的抗病毒性能下降;PEG修饰干扰素的抗肿瘤细胞增殖作用优于未修饰干扰素。更多还原

【Abstract】 OBJECTIVE: To improve the stability and biological activity, interferon can be modified by activated Polyethylene glycol (PEG) with the macromolecular design. To synthesize PEGylated IFN with a series of PEG modifier, compare their differences of heat stability, enzyme stability and stability of acid base. It was detected to antiviral activities and antineoplastic activities of PEGylated IFN.METHODS: The comblike copolymers of polycarboxylic acid (CPC) were synthesized and then reacted with PEG, obtained a conjugate-- PEGylated IFN. It was determined the molecular weight of conjugate by SDS-PAGE. The difference of heat stability, enzyme stability, and stability of acid base were compared between the PEGylated IFN and IFN. Antiviral activities can be detected by the system of Hep-2 cell and VSV. MTT assay was applied to assess antineoplastic activities of PEGylated IFN.RESULTS: There were 9 kinds of PEG-IFN conjugates, which were modified by various modifier and different modifying. The results of SDS-PAGE showed that the PEG-IFN conjugates were synthesized. The molecular weight of conjugate was 60000(modified by APEO90-4000) and 40000(modified by APEO90-20000 and APEO60-2000). The heat stability, enzyme stability and stability of acid base were increased conspicuously. MTT assay showed that PEG-IFN can inhibit the proliferation of tumor cells. Inhibitory effect of the 9 kinds of PEG-IFN (marked with 1-9) was increased. The increased rates were 56.3%, 35.2%, 17.8%, 42.3%, 23.5%, 14.6%,45.5%, 26.5%, 11.4% respectively. But antiviral activity of PEG-IFN was decreased. The decreased rates were 52%, 78%, 88%, 48%, 78%, 89%, 54%, 79%, 88% respectively.CONCLUSION: The heat stability, enzyme stability and stability of acid base of products were increased conspicuously. The antiviral effect of PEGylated IFN was not more effective than which of IFN. The effect of PEG-IFN was better than the effect of IFN in inhibiting tumor cells.更多还原