Development of a Novel, Proteinase-Activated Toxin Targeting Tumor Neovascularization
Abstract
In the first year of this grant we have proved the feasibility of the original hypothesis of this grant: that we can re-engineer the proteolytic activation site of alpha toxin such that it is only activated in the presence of proteases which are involved in tissue remodeling during the neovascularization of breast tumors and other solid tumors. We have generated several mutants of alpha toxin in which we have introduced a consensus site for gelatinases A and B. We have explored methods of production of these recombinant toxins and have carried out the complete characterization of one of these mutants, ATPLGlAG396. This mutant has the consensus gelatinase recognition sequence PLGIAG in place of the native sequence of K396RSVDS. We have shown that this mutant can be cleaved by purified gelatinases A and B in vitro and exhibits some selectivity for the killing of cells expressing gelatinases versus those which do not. These initial results are encouraging and in the second year of the grant we will begin the characterization of the many other mutants we have - generated and will expand our studies to examine other activation site mutants. Just prior to the submission of this report we have %partially characterized a second mutant, ATPLGIA 398 Unlike the pGEX 4T-2 expressed ATPLGI AG396 described above this mutant was expressed in the pET22b+ expression system and retains full hemolytic activity and can be activated in vitro by gelatinase B.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1998
- Accession Number
- ADB249654
Entities
People
- Rodney K. Tweten
Organizations
- University of Oklahoma