Two-Step Chromatographic Method for the Separation and Purification of Recombinant Angiogenesis Inhibitor Kringle 5
两步柱色谱法分离纯化重组肿瘤血管生长抑制因子Kringle 5

The Kringle 5 domain of plasminogen,which was previously shown to inhibit angiogenesis in vitro and in vivo,is one of the most potent angiogenesis inhibitors known to date.A two-step chromatographic method,which consists of Chelating Sepharose Fast Flow chelated with Ni2+ affinity medium and Sephadex G-75 medium,was established to separate and purify recombinant angiogenesis inhibitor Kringle 5(rK5).Through the two-step chromatographic purification process,the obtained rK5 was confirmed to be homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and its relative molecular mass was estimated to be about 32 000,which matched well with the prediction by gene sequence.Its purity was about 98%,and the total protein recovery of this method was 0.63%.In addition,it was found that it inhibited the blood vessel growth of chick embryo chorioallantoic membrane effectively.