Team:NTNU-Trondheim/novelapproach

In the previous years there has been several iGEM teams (some of them are the 2012 HKUST-Hong_Kong team, the 2012 NTNU_Trondheim team and the 2011 BYO_Provo team) that has had their main focus on treating or detecting cancer by introducing engineered bacteria into the human body. Although these biological systems are interesting and valuable on their own, introducing microorganisms that are capable of replicating into the blood stream is highly risky.

We believe that bacterial outer membrane vesicles (OMVs) is a much safer method for treating cancer and other diseases that are in need of a drug delivery vehicle. The focus within medical research on drug delivery vehicles today is mainly within nano medicine and the use of synthetically produced vehicles. There exist very few applications of this technology on the market as it has proven to be difficult to engineer a drug delivery vehicle that meets all of the necessary criteria. Some of these criteria include being stable in the bloodstream (by not being detected by immune cells), being able to recognize the target cells, have the ability to engulf into target cells, being nano sized (to prevent clogging in the blood vessels) and having a drug on/inside the vehicle. Many pathogenic bacteria such as Pseudomonas aeruginosa and enterogenic Escherichia coli naturally produce OMVs that meets many of these criteria. These OMVs contains toxic compounds and proteases and have the ability to associate and internalize themselves into eukaryotic cells (see figure 1) [1] . OMVs has in addition an appropriate size 20-250 nm [2] . The OMVs will be unable to replicate and is therefore a much safer option then introducing live bacteria into the blood stream.

Figure 1: Gold labeled vesicles from enterogenic E.coli that binds and internalizes in HT29 cancer cells [1].