title: Immunogenicity study of plasmid DNA encoding mouse cysteine-rich secretory protein-1 (mCRISP1) as a contraceptive vaccine.
abstract: OBJECTIVE
  To examine the immunocontraceptive properties of the plasmid pcDNA-mCRISP1 and compare them to the corresponding recombinant mCRISP1 (r-mCRISP1).
  
  
  METHODS
  RT-PCR and indirect immunofluorescence were performed to observe the mCRISP1 protein expression in COS-7 cells. Three groups of mice received three injections of r-mCRISP1, pcDNA-mCRISP1 or pcDNA vector, respectively. ELISA and Western blot were used to examine the immune responses and immunoreactivity of antisera. Sperm-egg penetration assay was performed to examine the effect of anti-mCRISP1 antibodies in vitro fertilization of mouse oocytes. Fertility and mean litter size were analysed by natural mating. Histological analysis was carried out to look for potential immunopathologic effects of the antibodies.
  
  
  RESULTS
  COS-7 cells transfected with pcDNA-mCRISP1 present the expression of mCRISP1. Both r-mCRISP1 and pcDNA-mCRISP1 raised an immune response against r-mCRISP1 protein and native CRISP1 in mouse sperm. The titres of anti-mCRISP1 antibodies from DNA immunized mice were significantly lower than that of r-mCRISP1 immunized mice, but it lasted relatively longer. Male and female pcDNA-mCRISP1 injected animals presented a statistically significant reduction in their fertility with no signs of immunopathologic effects.
  
  
  CONCLUSIONS
  These studies demonstrated the feasibility of generating an immune response to mCRISP1 protein by DNA vaccine and pcDNA-mCRISP1 plasmid causing significant anti-fertility potential.
authors.affiliation: Reproductive Medical Center, Renmin Hospital of Wuhan University, Wuhan, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Luo
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Yan
authors.initials: Y
authors.lastname: Cheng
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Tai-Lang
authors.initials: TL
authors.lastname: Yin
authors.forename: Wang-Ming
authors.initials: WM
authors.lastname: Xu
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Zou
mesh_terms: D000818:Animals; D001323:Autoantibodies / Q000276:immunology*; D019556:COS Cells; D002522:Chlorocebus aethiops; D005260:Female; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000235:genetics / Q000276:immunology*; D022642:Vaccines, Contraceptive / Q000235:genetics / Q000276:immunology*; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*
chemical_list: D001323:Autoantibodies; C486321:Crisp1 protein, mouse; D008562:Membrane Glycoproteins; D022642:Vaccines, Contraceptive; D019444:Vaccines, DNA