title: [Prokaryotic expression and purification of a tandem repeat of ovarian cancer antigen CA125 and preparation of its antiserum].
abstract: OBJECTIVE
  To establish a prokaryotic expression system of the tandem repeat of CA125 (CA125R),  express and purify the recombinant CA125R protein,  prepare its antiserum.
  
  
  METHODS
  The full gene sequence of one tandem repeat of CA125 was synthesized and cloned into pET-32a(+) to construct a prokaryotic expression vector of the CA125R protein (pET-CA125R). The pET-CA125R was transformed into E.coli BL21 (DE3) and the soluble expression conditions were optimized;  the pure recombinant CA125R protein was prepared by affinity Ni-NTA chromatography and identified by Western blotting. A rabbit was immunized with the pure recombinant CA125R protein to prepare its antiserum.
  
  
  RESULTS
  The prokaryotic expression vector of CA125R was successfully constructed. The optimal soluble induction expression conditions were 0.5 mmol/L isopropyl β-D-1-thiogalactopyranoside (IPTG) at 15DegreesCelsius for 6 h. Western blotting confirmed the pure CA125R recombinant protein of high purity. The prepared antiserum specifically recognized recombinant CA125R protein and natural CA125 glycoprotein.
  
  
  CONCLUSIONS
  We successfully established the efficient prokaryotic expression system of the CA125R,  and prepared the recombinant CA125R protein of high purity and its antiserum.
authors.affiliation: Chongqing Medical University, Chongqing, China. liangqindong@yahoo.com.cn
authors.forename: Qin-dong
authors.initials: QD
authors.lastname: Liang
authors.forename: Bian-qin
authors.initials: BQ
authors.lastname: Guo
authors.forename: Xian-tao
authors.initials: XT
authors.lastname: Wang
authors.forename: Wu-xian
authors.initials: WX
authors.lastname: Li
authors.forename: Jin-yu
authors.initials: JY
authors.lastname: Dong
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.forename: Zhi-guang
authors.initials: ZG
authors.lastname: Tu
mesh_terms: D000818:Animals; D018394:CA-125 Antigen / Q000235:genetics* / Q000276:immunology; D004926:Escherichia coli / Q000235:genetics; D007106:Immune Sera / Q000276:immunology*; D011817:Rabbits; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D020080:Tandem Repeat Sequences
chemical_list: D018394:CA-125 Antigen; D007106:Immune Sera; D011994:Recombinant Proteins