The feasibility of expression of a ricin toxin transgene in plant tobacco cells was demonstrated. This system offers advantages over other expression systems that have been used: 1) ability to perform complex post- translational modifications, 2) strong signal peptide sequences to protect the ribosomes from ricin toxicity, 3) greater ease of mass production. Using this expression system the molecular variables important in the construction of a ricin fusion toxin with targeted cell killing and minimal non-specific toxicity will be investigated.
The FIRST AIM i s to define the role of the cleavable interchain disulfide bond for ricin toxicity;
the SECOND AIM i s to define the ability of the plant expression system to produce double and triple ricin B chain mutants;
the THIRD AIM i s to use cytoxic qualities of a KDEL-modified ricin toxin;
the FOURTH AIM i s to use the knowledge from the first 3 AIMS to design a single-chain antibody (against neuroblastoma antigen GD2) ricin fusion protein.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29CA074677-03
Application #
2837744
Study Section
Experimental Therapeutics Subcommittee 1 (ET)
Program Officer
Finerty, John F
Project Start
1997-01-15
Project End
2001-11-30
Budget Start
1999-08-27
Budget End
1999-11-30
Support Year
3
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Medical University of South Carolina
Department
Surgery
Type
Schools of Medicine
DUNS #
183710748
City
Charleston
State
SC
Country
United States
Zip Code
29425
Thomas, Patrick B; Delatte, Stephen J; Sutphin, Aimee et al. (2002) Effective targeted cytotoxicity of neuroblastoma cells. J Pediatr Surg 37:539-44
Tagge, E; Harris, B; Burbage, C et al. (1997) Synthesis of green fluorescent protein-ricin and monitoring of its intracellular trafficking. Bioconjug Chem 8:743-50