title: Identification of Enterococcus faecalis antigens specifically expressed in vivo.
abstract: OBJECTIVE
  Molecular mechanism of the pathogenicity of Enterococcus faecalis (E. faecalis), a suspected endodontic pathogen, has not yet been adequately elucidated due to limited information on its virulence factors. Here we report the identification of in vivo expressed antigens of E. faecalis by using a novel immunoscreening technique called change-mediated antigen technology (CMAT) and an experimental animal model of endodontic infection.
  
  
  METHODS
  Among 4,500 E. coli recombinant clones screened, 19 positive clones reacted reproducibly with hyperimmune sera obtained from rabbits immunized with E. faecalis cells isolated from an experimental endodontic infection. DNA sequences from 16 of these in vivo-induced (IVI) genes were determined.
  
  
  RESULTS
  Identified protein antigens of E. faecalis included enzymes involved in housekeeping functions, copper resistance protein, putative outer membrane proteins, and proteins of unknown function.
  
  
  CONCLUSIONS
  In vivo expressed antigens of E. faecalis could be identified by using a novel immune-screening technique CMAT and an experimental animal model of endodontic infection. Detailed analysis of these IVI genes will lead to a better understanding of the molecular mechanisms involved in the endodontic infection of E. faecalis.
authors.affiliation: Department of Dental Education, Dental Science Research Institute and BK21 Project, School of Dentistry, Gwangju, Korea. ; Department of Periodontology, Dental Science Research Institute and BK21 Project, School of Dentistry, Gwangju, Korea.
authors.forename: Seok-Woo
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Department of Maxillofacial Surgery, Dental Science Research Institute and BK21 Project, School of Dentistry, Gwangju, Korea.
authors.forename: Uttom K
authors.initials: UK
authors.lastname: Shet
authors.affiliation: Department of Prosthodontics, Dental Science Research Institute and BK21 Project, School of Dentistry, Gwangju, Korea.
authors.forename: Sang-Won
authors.initials: SW
authors.lastname: Park
authors.affiliation: Department of Prosthodontics, Dental Science Research Institute and BK21 Project, School of Dentistry, Gwangju, Korea.
authors.forename: Hyun-Pil
authors.initials: HP
authors.lastname: Lim
authors.affiliation: Department of Prosthodontics, Dental Science Research Institute and BK21 Project, School of Dentistry, Gwangju, Korea.
authors.forename: Kwi-Dug
authors.initials: KD
authors.lastname: Yun
authors.affiliation: Department of Veterinary Medicine, Chonnam National University, Gwangju, Korea.
authors.forename: Seong Soo
authors.initials: SS
authors.lastname: Kang
authors.affiliation: Department of Veterinary Medicine, Chonnam National University, Gwangju, Korea.
authors.forename: Se Eun
authors.initials: SE
authors.lastname: Kim
keywords: Antigen; Enterococcus faecalis; In vivo; Pulpitis; Virulence factor