Protection elicited by immunization of ClpP against Streptococcus pneumoniae infection in mice / 中华微生物学和免疫学杂志

ABSTRACT

Objective To obtain purified ClpP produced by prokaryotic expression system,and to evaluate the protection effect elicited by ClpP in animal protection test.Methods The template DNA was isolated from the culture of TIGR4 Streptococcus pneumoniae.The complete ClpP open reading frame(ORF)was cloned into pET-32a expression vector by gene recombination technology in vitro.After prokaryotic expression,purification and sequence identification,the recombinant ClpP were innoculated into mice,and at the same time a group of mice were inoculated with the antibody to ClpP.We monitored the survival time of the innoculated mice after being challenged intraperitoneally with,TIGR4.Results We obtained high-expressed recombinant antigen protein which was then identified by Western blot,and we have got the recombinant antigen protein with a purity of more than 90%after being purified through Ni2+ affinity chromatography and processed by dialysis.The sunrvival time of mice immunized with ClpP or ClpP antibody were significantly langer than that of the mice received PBS.Conclusion The recombinant ClpP antigen protein can elicit protection to the invasive S.pneumoniae infection in mice,which might make ClpP as a candidate of S.pneumoniae vaccine.