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Visualization of tumors and metastases in live animals with bacteria and vaccinia virus encoding light-emitting proteins

A Corrigendum to this article was published on 01 April 2004


We have shown that bacteria injected intravenously into live animals entered and replicated in solid tumors and metastases. The tumor-specific amplification process was visualized in real time using luciferase-catalyzed luminescence and green fluorescent protein fluorescence, which revealed the locations of the tumors and metastases. Escherichia coli and three attenuated pathogens (Vibrio cholerae, Salmonella typhimurium, and Listeria monocytogenes) all entered tumors and replicated. Similarly, the cytosolic vaccinia virus also showed tumor-specific replication, as visualized by real-time imaging. These findings indicate that neither auxotrophic mutations, nor vaccinia virus deficient for the thymidine kinase gene, nor anaerobic growth conditions were required for tumor specificity and intratumoral replication. We observed localization of tumors by light-emitting microorganisms in immunocompetent and in immunocompromised rodents with syngeneic and allogeneic tumors. Based on their 'tumor-finding' nature, bacteria and viruses may be designed to carry multiple genes for detection and treatment of cancer.

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Figure 1: Visualization with the low light imager of the distribution of light-emitting bacteria injected intravenously in nude mice.
Figure 2: Intravenously injected bacteria and viruses accumulate and replicate in subcutaneous C6 rat glioma tumors in nude mice as visualized by light emission.
Figure 3: Localization of bacterial colonization and viral infection in subcutaneous C6 glioma tumors.
Figure 4: Bacterial and vaccinia virus show tumor-specific localization in different tumorous mice models.
Figure 5: Intravenously delivered light-emitting bacteria and recombinant vaccinia virus mark the location of primary breast tumors and their metastases in nude mice.


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The authors thank M. Lilly for generating mice with bladder tumors, I. Fodor for help with prostate tumor mice and for access to the rVV-RUC-GFP virus, D. Gridley for developing intracranial glioma tumors, D. deLeon and J. Tian for mice with MCF-7 implants and K. Oberg for access to the stereo fluorescence microscope. We would like to acknowledge the help and scientific criticisms of C. Slattery and F. Grummt during the preparation of this manuscript. Y.A.Y. was a recipient of a graduate fellowship from LLU. The research was supported in part by LLU, by Genelux, by an SFB travel award to A.A.S., by the research prize from A.V. Humboldt Foundation, Germany, awarded to A.A.S., and by an SFB award to W.G.

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Correspondence to Aladar A Szalay.

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A.A.S. is a cofounder and shareholder of Genelux. Y.A.Y., T.M.T. and Q.Z. are employed by Genelux.

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Yu, Y., Shabahang, S., Timiryasova, T. et al. Visualization of tumors and metastases in live animals with bacteria and vaccinia virus encoding light-emitting proteins. Nat Biotechnol 22, 313–320 (2004).

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