title: Noninvasive real-time imaging of tumors and metastases using tumor-targeting light-emitting Escherichia coli.
abstract: OBJECTIVE
  A number of bacteria types are known to preferentially grow in tumors. We have taken advantage of this phenomenon to target luciferase-expressing Escherichia coli to tumors and metastases in mouse models to image them noninvasively.
  
  
  RESULTS
  After intravenous injection of pLux-expressing E. coli (10(8) CFU), bioluminescence signals from the bacteria were detected exclusively in tumor tissue after 24 hours. The balanced-lethal host-vector system using the gene encoding aspartate beta-semialdehyde dehydrogenase (asd) enabled stable maintenance of the pLux in the tumor-targeting E. coli. This phenomenon of selective tumor targeting and proliferation of E. coli was observed in a diverse range of tumors implanted in nude mice. More importantly, E. coli was capable of targeting both primary tumors and metastases, enabling them to be imaged noninvasively in both nude and immunocompetent mice.
  
  
  CONCLUSIONS
  Our results suggest the potential clinical use of this technology for tumor targeting.
authors.affiliation: Laboratory of In Vivo Molecular Imaging, Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, South Korea. jjmin@jnu.ac.kr
authors.forename: Jung-Joon
authors.initials: JJ
authors.lastname: Min
authors.forename: Hyun-Ju
authors.initials: HJ
authors.lastname: Kim
authors.forename: Jae Hyo
authors.initials: JH
authors.lastname: Park
authors.forename: Sungmin
authors.initials: S
authors.lastname: Moon
authors.forename: Jae Ho
authors.initials: JH
authors.lastname: Jeong
authors.forename: Yeoung-Jin
authors.initials: YJ
authors.lastname: Hong
authors.forename: Kyoung-Oh
authors.initials: KO
authors.lastname: Cho
authors.forename: Jong Hee
authors.initials: JH
authors.lastname: Nam
authors.forename: Nacksung
authors.initials: N
authors.lastname: Kim
authors.forename: Young-Kyu
authors.initials: YK
authors.lastname: Park
authors.forename: Hee-Seung
authors.initials: HS
authors.lastname: Bom
authors.forename: Joon Haeng
authors.initials: JH
authors.lastname: Rhee
authors.forename: Hyon E
authors.initials: HE
authors.lastname: Choy
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D004926:Escherichia coli / Q000378:metabolism*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008027:Light; D008156:Luciferases / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009362:Neoplasm Metastasis; D009369:Neoplasms / Q000175:diagnosis* / Q000382:microbiology* / Q000473:pathology; D017785:Photons; D051381:Rats; D051598:Whole Body Imaging
chemical_list: D008156:Luciferases