目的　建立一种从血清中提纯 C2的方法 ,得到稳定的、有活性的纯品 ,便于今后进一步研究其生理病理功能 .方法　利用冷球蛋白沉淀、优球蛋白沉淀、离子交换色谱、硫酸铵沉淀和亲和色谱几种方法 ,将血清中不同性质的杂蛋白除去 ,选择相对简单且分离效果好的条件 ,提高终产物中目标蛋白 C2的纯度和含量 .结果　成功地从 1L血浆中提纯到了 2 .49m g C2 ,产率为 12 .46 % ,活性回收率为 13.6 8% .终产物在 p H中性时稳定 ,且无需加入蛋白稳定剂 .结论　本法与以往纯化 C2的方法相比 ,简便可行 ,产率及活性回收率较高 ,适用于实验室研究和大规模制备 OBJECTIVE To establish a method of purifying C2 from serum and obtain a stable and active pure product for further study of its physiological and pathological functions in future.Methods Cryoprecipitation, euglobulin precipitation, ion exchange chromatography, ammonium sulfate precipitation And several methods of affinity chromatography, the different nature of the serum protein in the removal of impurities, the choice of relatively simple and good separation conditions to improve the purity and content of the final protein C2 in the final product was successfully purified from 1L plasma to 2. 49m g C2 with a yield of 12.46% and an activity recovery of 13.68%. The final product was stable at p H neutrality without addition of a protein stabilizer.Conclusion This method is simpler than previous methods of purifying C2 Feasible, high yield and activity recovery, suitable for laboratory research and large-scale preparation