Difference between revisions of "Team:CU-Boulder/Human Practices"

We very much wanted to continue off the work we had laid out at iGEM last year, using our mutant and photo-openable EutS compartments. However, last year’s iGEM team did not really focus on what you could use our compartments for. This year, we started out early by asking ourselves what human problem we could solve using nano-scale isolation and sequestration that could open on demand.

Small molecule drug delivery remains the biggest field in the pharmaceutical industry today. Every year, billions of these drugs are synthesized and consumed by humans in almost every corner of the world, for far ranging purposes. But there are problems with small molecule delivery: non-specificity of interactions and the relatively high concentrations you sometimes need to use to generate the effects are a major cause of “side effects” in pharmaceuticals. We wondered if this was a problem we could solve if we used our nanocompartments to deliver drugs to only their intended receptors, opening there on demand. This would cut down on widespread side effects throughout the body.

While we understood that this was by no means a perfect solution to this problem, as cost, storage, and administration could prove effective barriers, it could also allow for new small molecule treatments for conditions that might have never worked otherwise, and so we decided to forge ahead with this idea in mind.

To that end, we developed our Luciferase and TNF-alpha fusion cargo proteins, and assays which could test our EutS derived compartments as a means of treating cells or binding other ligands. While we still aren’t sure that would be usable or practical in its current state, it would nevertheless serve as a proof of concept that could be iterated on for years to come, potentially revolutionizing small molecule development with new approaches never before possible.

Other concerns also arise when we consider the use of our compartment in vivo. These two considerations are the toxicity of Azobenzene and the potential immune response to EutS protein cages. At the least, computational epitope mapping of EutS monomers seems to indicate that a strong immune response to our compartments would not be very likely, a major plus as a drug delivery tool.

While no trials have been conducted on the toxicity of the non-canonical amino acid AzoPhe, it has been reported that azobenzene in the body can be reduced into phenylenediamine and benzidine. Phenylenediamine is only a mild potential allergen (https://pubchem.ncbi.nlm.nih.gov/compound/p-Phenylenediamine#section=NIOSH-Toxicity-Data), but Benzidine is confirmed as a known human carcinogen (https://pubchem.ncbi.nlm.nih.gov/compound/benzidine#section=Carcinogen). If we were to continue to explore the possibility of compartment based drug delivery, we would likely eventually need to discontinue our use of AzoPhe in favor of a photoisomerizable compound with less potential for toxicity, or to use a different method of compartment breakage. Nevertheless, we had AzoPhe and an incorporation system for it already, and decided that at least as a proof of concept it would be worth forging ahead.