Noninvasive real-time imaging of tumors and metastases using tumor-targeting light-emitting Escherichia coli.
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.
Min
Jung-Joon
JJ
Laboratory of In Vivo Molecular Imaging, Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, South Korea. jjmin@jnu.ac.kr
Kim
Hyun-Ju
HJ
Park
Jae Hyo
JH
Moon
Sungmin
S
Jeong
Jae Ho
JH
Hong
Yeoung-Jin
YJ
Cho
Kyoung-Oh
KO
Nam
Jong Hee
JH
Kim
Nacksung
N
Park
Young-Kyu
YK
Bom
Hee-Seung
HS
Rhee
Joon Haeng
JH
Choy
Hyon E
HE
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
D008156:Luciferases