中文摘要：

通过制备仿刺参补体C3（AjC3）多克隆抗体，为进一步研究仿刺参补体Ajc3免疫机制奠定基础。利用PCR技术扩增AjC3部分基因片段（4556～5110bp），将该片段与原核表达载体pGS-21a连接。将重组表达质粒转化到Transetta（DE3）中经IPTG诱导表达。表达的重组蛋白经镍柱纯化后，作为抗原免疫小鼠制备舢C3多克隆抗体。分别用间接EusA，Westernblot检测抗体的效价和特异性。结果显示，PCR扩增得到约555bp的目的片段，重组蛋白分子量大小约56ku；间接ELISA检测抗体效价达1：25600，Westernblot结果显示，多克隆抗体具有良好的特异性。该试验成功的制备了补体AjC3多克隆抗体，为补体AjC3的进一步研究提供了检测工具。

英文摘要：

The polyclonal antibody of complement component C3 （AjC3） was prepared to provide references for further research on immunologic mechanism in sea cucumber Apostichopus japonicus. The gene frag- ments of AjC3 was amplified by PCR and inserted into the prokaryotic expression vector pGS-21a. The re- combinant plasmid was transformed into the transetta（DE3） and induced to express by IPTG. The expres- sion products were purified by Ni-NTA. The recombinant protein as antigen was employed to immunize mice to prepare the polyclonal antibody. The title and specificity of the polyclonal antibody were deter- mined by indirect ELISA and Western blot. The results showed that the length of PCR product was 555 bp. The size of recombinant protein was 56 ku. The title was 1 ：25600 by indirect ELISA. Western blot proved that the polyclonal antibody had good specificity and was successfull prepared, which provided helpful tools for further researches on AjC3.